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[PATCH 0/4] kvm: cpuid: fix cpuid nent field

by Emanuele Giuseppe Esposito

This series aims to clarify the behavior of KVM_GET_EMULATED_CPUID and KVM_GET_SUPPORTED ioctls, and fix a corner case where the nent field of the struct kvm_cpuid2 is matching the amount of entries that kvm returns. Patch 1 proposes the nent field fix to cpuid.c, patch 2 updates the ioctl documentation accordingly and patches 3 and 4 provide a selftest to check KVM_GET_EMULATED_CPUID accordingly. Signed-off-by: Emanuele Giuseppe Esposito <eesposit(a)redhat.com> --- v2: - better fix in cpuid.c, perform the nent check after the switch statement - fix bug in get_emulated_cpuid.c selftest, each entry needs to have at least the padding zeroed otherwise it fails. Emanuele Giuseppe Esposito (4): kvm: cpuid: adjust the returned nent field of kvm_cpuid2 for KVM_GET_SUPPORTED_CPUID and KVM_GET_EMULATED_CPUID Documentation: kvm: update KVM_GET_EMULATED_CPUID ioctl description selftests: add kvm_get_emulated_cpuid selftests: kvm: add get_emulated_cpuid test Documentation/virt/kvm/api.rst | 10 +- arch/x86/kvm/cpuid.c | 35 ++-- tools/testing/selftests/kvm/.gitignore | 1 + tools/testing/selftests/kvm/Makefile | 1 + .../selftests/kvm/include/x86_64/processor.h | 1 + .../selftests/kvm/lib/x86_64/processor.c | 33 +++ .../selftests/kvm/x86_64/get_emulated_cpuid.c | 198 ++++++++++++++++++ 7 files changed, 256 insertions(+), 23 deletions(-) create mode 100644 tools/testing/selftests/kvm/x86_64/get_emulated_cpuid.c -- 2.30.2

4 years, 3 months

2
6
0 0

[PATCH V5 00/10] PKS: Add Protection Key Supervisor support

by ira.weiny＠intel.com

From: Ira Weiny <ira.weiny(a)intel.com> Introduce a new page protection mechanism for supervisor pages, Protection Key Supervisor (PKS). Generally PKS enables protections on 'domains' of supervisor pages to limit supervisor mode access to pages beyond the normal paging protections. PKS works in a similar fashion to user space pkeys, PKU. As with PKU, supervisor pkeys are checked in addition to normal paging protections and Access or Writes can be disabled via a MSR update without TLB flushes when permissions change. Also like PKU, a page mapping is assigned to a domain by setting pkey bits in the page table entry for that mapping. Access is controlled through a PKRS register which is updated via WRMSR/RDMSR. XSAVE is not supported for the PKRS MSR. Therefore the implementation saves/restores the MSR across context switches and during exceptions. Nested exceptions are supported by each exception getting a new PKS state. For consistent behavior with current paging protections, pkey 0 is reserved and configured to allow full access via the pkey mechanism, thus preserving the default paging protections on mappings with the default pkey value of 0. Other keys, (1-15) are allocated by an allocator which prepares us for key contention from day one. Kernel users should be prepared for the allocator to fail either because of key exhaustion or due to PKS not being supported on the CPU instance. The following are key attributes of PKS. 1) Fast switching of permissions 1a) Prevents access without page table manipulations 1b) No TLB flushes required 2) Works on a per thread basis PKS is available with 4 and 5 level paging. Like PKRU it consumes 4 bits from the PTE to store the pkey within the entry. All code to support PKS is configured via ARCH_ENABLE_SUPERVISOR_PKEYS which is designed to only be turned on when a user is configured on in the kernel. Those users must depend on ARCH_HAS_SUPERVISOR_PKEYS to properly work with other architectures which do not yet support PKS. Originally this series was submitted as part of a large patch set which converted the kmap call sites.[1] Many follow on discussions revealed a few problems. The first of which was that some callers leak a kmap mapping across threads rather than containing it to a critical section. Attempts were made to see if these 'global kmaps' could be supported.[2] However, supporting global kmaps had many problems. Work is being done in parallel on converting as many kmap calls to the new kmap_local_page().[3] Changes from V4 [5] From kernel test robot <lkp(a)intel.com> Fix i386 build: pks_init_task not found Move MSR_IA32_PKRS and INIT_PKRS_VALUE into patch 5 where they are first 'used'. (Technically nothing is 'used' until the final test patch. But review wise this is much cleaner.) From Sean Christoperson Add documentation details on what happens if the pkey is violated Change cpu_feature_enabled to be in WARN_ON check Clean up commit message of patch 6 Fix some checkpatch errors [1] https://lore.kernel.org/lkml/20201009195033.3208459-1-ira.weiny@intel.com/ [2] https://lore.kernel.org/lkml/87mtycqcjf.fsf@nanos.tec.linutronix.de/ [3] https://lore.kernel.org/lkml/20210128061503.1496847-1-ira.weiny@intel.com/ https://lore.kernel.org/lkml/20210210062221.3023586-1-ira.weiny@intel.com/ https://lore.kernel.org/lkml/20210205170030.856723-1-ira.weiny@intel.com/ https://lore.kernel.org/lkml/20210217024826.3466046-1-ira.weiny@intel.com/ [4] https://lore.kernel.org/lkml/20201106232908.364581-1-ira.weiny@intel.com/ [5] https://lore.kernel.org/lkml/20210322053020.2287058-1-ira.weiny@intel.com/ Fenghua Yu (1): x86/pks: Add PKS kernel API Ira Weiny (9): x86/pkeys: Create pkeys_common.h x86/fpu: Refactor arch_set_user_pkey_access() for PKS support x86/pks: Add additional PKEY helper macros x86/pks: Add PKS defines and Kconfig options x86/pks: Add PKS setup code x86/fault: Adjust WARN_ON for PKey fault x86/pks: Preserve the PKRS MSR on context switch x86/entry: Preserve PKRS MSR across exceptions x86/pks: Add PKS test code Documentation/core-api/protection-keys.rst | 112 +++- arch/x86/Kconfig | 1 + arch/x86/entry/calling.h | 26 + arch/x86/entry/common.c | 58 ++ arch/x86/entry/entry_64.S | 22 +- arch/x86/entry/entry_64_compat.S | 6 +- arch/x86/include/asm/cpufeatures.h | 1 + arch/x86/include/asm/disabled-features.h | 8 +- arch/x86/include/asm/msr-index.h | 1 + arch/x86/include/asm/pgtable.h | 10 +- arch/x86/include/asm/pgtable_types.h | 12 + arch/x86/include/asm/pkeys.h | 4 + arch/x86/include/asm/pkeys_common.h | 34 + arch/x86/include/asm/pks.h | 54 ++ arch/x86/include/asm/processor-flags.h | 2 + arch/x86/include/asm/processor.h | 47 +- arch/x86/include/uapi/asm/processor-flags.h | 2 + arch/x86/kernel/cpu/common.c | 2 + arch/x86/kernel/fpu/xstate.c | 22 +- arch/x86/kernel/head_64.S | 7 +- arch/x86/kernel/process.c | 3 + arch/x86/kernel/process_64.c | 2 + arch/x86/mm/fault.c | 31 +- arch/x86/mm/pkeys.c | 218 +++++- include/linux/pgtable.h | 4 + include/linux/pkeys.h | 34 + kernel/entry/common.c | 14 +- lib/Kconfig.debug | 11 + lib/Makefile | 3 + lib/pks/Makefile | 3 + lib/pks/pks_test.c | 693 ++++++++++++++++++++ mm/Kconfig | 5 + tools/testing/selftests/x86/Makefile | 3 +- tools/testing/selftests/x86/test_pks.c | 150 +++++ 34 files changed, 1528 insertions(+), 77 deletions(-) create mode 100644 arch/x86/include/asm/pkeys_common.h create mode 100644 arch/x86/include/asm/pks.h create mode 100644 lib/pks/Makefile create mode 100644 lib/pks/pks_test.c create mode 100644 tools/testing/selftests/x86/test_pks.c -- 2.28.0.rc0.12.gb6a658bd00c9

4 years, 3 months

3
12
0 0

[PATCH v8 1/2] mm: huge_memory: a new debugfs interface for splitting THP tests.

by Zi Yan

From: Zi Yan <ziy(a)nvidia.com> We did not have a direct user interface of splitting the compound page backing a THP and there is no need unless we want to expose the THP implementation details to users. Make <debugfs>/split_huge_pages accept a new command to do that. By writing "<pid>,<vaddr_start>,<vaddr_end>" to <debugfs>/split_huge_pages, THPs within the given virtual address range from the process with the given pid are split. It is used to test split_huge_page function. In addition, a selftest program is added to tools/testing/selftests/vm to utilize the interface by splitting PMD THPs and PTE-mapped THPs. This does not change the old behavior, i.e., writing 1 to the interface to split all THPs in the system. Changelog: >From v7: 1. Used the right way of looping through page cache pages. (the error was pointed out by Matthew Wilcox) >From v6: 1. pr_info -> pr_debug. 2. Added cond_resched() in all split loops. (suggested by David Rientjes) >From v5: 1. Skipped special VMAs and other fixes. (suggested by Yang Shi) >From v4: 1. Fixed the error code return issue, spotted by kernel test robot <lkp(a)intel.com>. >From v3: 1. Factored out split huge pages in the given pid code to a separate function. 2. Added the missing put_page for not split pages. 3. pr_debug -> pr_info, make reading results simpler. >From v2: 1. Reused existing <debugfs>/split_huge_pages interface. (suggested by Yang Shi) >From v1: 1. Removed unnecessary calling to vma_migratable, spotted by kernel test robot <lkp(a)intel.com>. 2. Dropped the use of find_mm_struct and code it directly, since there is no need for the permission check in that function and the function is only available when migration is on. 3. Added some comments in the selftest program to clarify how PTE-mapped THPs are formed. Signed-off-by: Zi Yan <ziy(a)nvidia.com> Reviewed-by: Yang Shi <shy828301(a)gmail.com> --- mm/huge_memory.c | 155 ++++++++- tools/testing/selftests/vm/.gitignore | 1 + tools/testing/selftests/vm/Makefile | 1 + .../selftests/vm/split_huge_page_test.c | 318 ++++++++++++++++++ 4 files changed, 467 insertions(+), 8 deletions(-) create mode 100644 tools/testing/selftests/vm/split_huge_page_test.c diff --git a/mm/huge_memory.c b/mm/huge_memory.c index 8eba529a0f17..1bcab247aea8 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -7,6 +7,7 @@ #include <linux/mm.h> #include <linux/sched.h> +#include <linux/sched/mm.h> #include <linux/sched/coredump.h> #include <linux/sched/numa_balancing.h> #include <linux/highmem.h> @@ -2927,16 +2928,14 @@ static struct shrinker deferred_split_shrinker = { }; #ifdef CONFIG_DEBUG_FS -static int split_huge_pages_set(void *data, u64 val) +static void split_huge_pages_all(void) { struct zone *zone; struct page *page; unsigned long pfn, max_zone_pfn; unsigned long total = 0, split = 0; - if (val != 1) - return -EINVAL; - + pr_debug("Split all THPs\n"); for_each_populated_zone(zone) { max_zone_pfn = zone_end_pfn(zone); for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++) { @@ -2960,15 +2959,155 @@ static int split_huge_pages_set(void *data, u64 val) unlock_page(page); next: put_page(page); + cond_resched(); } } - pr_info("%lu of %lu THP split\n", split, total); + pr_debug("%lu of %lu THP split\n", split, total); +} - return 0; +static inline bool vma_not_suitable_for_thp_split(struct vm_area_struct *vma) +{ + return vma_is_special_huge(vma) || (vma->vm_flags & VM_IO) || + is_vm_hugetlb_page(vma); +} + +static int split_huge_pages_pid(int pid, unsigned long vaddr_start, + unsigned long vaddr_end) +{ + int ret = 0; + struct task_struct *task; + struct mm_struct *mm; + unsigned long total = 0, split = 0; + unsigned long addr; + + vaddr_start &= PAGE_MASK; + vaddr_end &= PAGE_MASK; + + /* Find the task_struct from pid */ + rcu_read_lock(); + task = find_task_by_vpid(pid); + if (!task) { + rcu_read_unlock(); + ret = -ESRCH; + goto out; + } + get_task_struct(task); + rcu_read_unlock(); + + /* Find the mm_struct */ + mm = get_task_mm(task); + put_task_struct(task); + + if (!mm) { + ret = -EINVAL; + goto out; + } + + pr_debug("Split huge pages in pid: %d, vaddr: [0x%lx - 0x%lx]\n", + pid, vaddr_start, vaddr_end); + + mmap_read_lock(mm); + /* + * always increase addr by PAGE_SIZE, since we could have a PTE page + * table filled with PTE-mapped THPs, each of which is distinct. + */ + for (addr = vaddr_start; addr < vaddr_end; addr += PAGE_SIZE) { + struct vm_area_struct *vma = find_vma(mm, addr); + unsigned int follflags; + struct page *page; + + if (!vma || addr < vma->vm_start) + break; + + /* skip special VMA and hugetlb VMA */ + if (vma_not_suitable_for_thp_split(vma)) { + addr = vma->vm_end; + continue; + } + + /* FOLL_DUMP to ignore special (like zero) pages */ + follflags = FOLL_GET | FOLL_DUMP; + page = follow_page(vma, addr, follflags); + + if (IS_ERR(page)) + continue; + if (!page) + continue; + + if (!is_transparent_hugepage(page)) + goto next; + + total++; + if (!can_split_huge_page(compound_head(page), NULL)) + goto next; + + if (!trylock_page(page)) + goto next; + + if (!split_huge_page(page)) + split++; + + unlock_page(page); +next: + put_page(page); + cond_resched(); + } + mmap_read_unlock(mm); + mmput(mm); + + pr_debug("%lu of %lu THP split\n", split, total); + +out: + return ret; } -DEFINE_DEBUGFS_ATTRIBUTE(split_huge_pages_fops, NULL, split_huge_pages_set, - "%llu\n"); + +#define MAX_INPUT_BUF_SZ 255 + +static ssize_t split_huge_pages_write(struct file *file, const char __user *buf, + size_t count, loff_t *ppops) +{ + static DEFINE_MUTEX(split_debug_mutex); + ssize_t ret; + char input_buf[MAX_INPUT_BUF_SZ]; /* hold pid, start_vaddr, end_vaddr */ + int pid; + unsigned long vaddr_start, vaddr_end; + + ret = mutex_lock_interruptible(&split_debug_mutex); + if (ret) + return ret; + + ret = -EFAULT; + + memset(input_buf, 0, MAX_INPUT_BUF_SZ); + if (copy_from_user(input_buf, buf, min_t(size_t, count, MAX_INPUT_BUF_SZ))) + goto out; + + input_buf[MAX_INPUT_BUF_SZ - 1] = '\0'; + ret = sscanf(input_buf, "%d,0x%lx,0x%lx", &pid, &vaddr_start, &vaddr_end); + if (ret == 1 && pid == 1) { + split_huge_pages_all(); + ret = strlen(input_buf); + goto out; + } else if (ret != 3) { + ret = -EINVAL; + goto out; + } + + ret = split_huge_pages_pid(pid, vaddr_start, vaddr_end); + if (!ret) + ret = strlen(input_buf); +out: + mutex_unlock(&split_debug_mutex); + return ret; + +} + +static const struct file_operations split_huge_pages_fops = { + .owner = THIS_MODULE, + .write = split_huge_pages_write, + .llseek = no_llseek, +}; static int __init split_huge_pages_debugfs(void) { diff --git a/tools/testing/selftests/vm/.gitignore b/tools/testing/selftests/vm/.gitignore index c8deddc81e7a..da92ded5a27c 100644 --- a/tools/testing/selftests/vm/.gitignore +++ b/tools/testing/selftests/vm/.gitignore @@ -23,3 +23,4 @@ write_to_hugetlbfs hmm-tests memfd_secret local_config.* +split_huge_page_test diff --git a/tools/testing/selftests/vm/Makefile b/tools/testing/selftests/vm/Makefile index 38e25b90f8bf..266580ea938c 100644 --- a/tools/testing/selftests/vm/Makefile +++ b/tools/testing/selftests/vm/Makefile @@ -43,6 +43,7 @@ TEST_GEN_FILES += on-fault-limit TEST_GEN_FILES += thuge-gen TEST_GEN_FILES += transhuge-stress TEST_GEN_FILES += userfaultfd +TEST_GEN_FILES += split_huge_page_test ifeq ($(MACHINE),x86_64) CAN_BUILD_I386 := $(shell ./../x86/check_cc.sh $(CC) ../x86/trivial_32bit_program.c -m32) diff --git a/tools/testing/selftests/vm/split_huge_page_test.c b/tools/testing/selftests/vm/split_huge_page_test.c new file mode 100644 index 000000000000..2c0c18e60c57 --- /dev/null +++ b/tools/testing/selftests/vm/split_huge_page_test.c @@ -0,0 +1,318 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * A test of splitting PMD THPs and PTE-mapped THPs from a specified virtual + * address range in a process via <debugfs>/split_huge_pages interface. + */ + +#define _GNU_SOURCE +#include <stdio.h> +#include <stdlib.h> +#include <unistd.h> +#include <inttypes.h> +#include <string.h> +#include <fcntl.h> +#include <sys/mman.h> +#include <malloc.h> +#include <stdbool.h> + +uint64_t pagesize; +unsigned int pageshift; +uint64_t pmd_pagesize; + +#define PMD_SIZE_PATH "/sys/kernel/mm/transparent_hugepage/hpage_pmd_size" +#define SPLIT_DEBUGFS "/sys/kernel/debug/split_huge_pages" +#define SMAP_PATH "/proc/self/smaps" +#define INPUT_MAX 80 + +#define PFN_MASK ((1UL<<55)-1) +#define KPF_THP (1UL<<22) + +int is_backed_by_thp(char *vaddr, int pagemap_file, int kpageflags_file) +{ + uint64_t paddr; + uint64_t page_flags; + + if (pagemap_file) { + pread(pagemap_file, &paddr, sizeof(paddr), + ((long)vaddr >> pageshift) * sizeof(paddr)); + + if (kpageflags_file) { + pread(kpageflags_file, &page_flags, sizeof(page_flags), + (paddr & PFN_MASK) * sizeof(page_flags)); + + return !!(page_flags & KPF_THP); + } + } + return 0; +} + + +static uint64_t read_pmd_pagesize(void) +{ + int fd; + char buf[20]; + ssize_t num_read; + + fd = open(PMD_SIZE_PATH, O_RDONLY); + if (fd == -1) { + perror("Open hpage_pmd_size failed"); + exit(EXIT_FAILURE); + } + num_read = read(fd, buf, 19); + if (num_read < 1) { + close(fd); + perror("Read hpage_pmd_size failed"); + exit(EXIT_FAILURE); + } + buf[num_read] = '\0'; + close(fd); + + return strtoul(buf, NULL, 10); +} + +static int write_file(const char *path, const char *buf, size_t buflen) +{ + int fd; + ssize_t numwritten; + + fd = open(path, O_WRONLY); + if (fd == -1) + return 0; + + numwritten = write(fd, buf, buflen - 1); + close(fd); + if (numwritten < 1) + return 0; + + return (unsigned int) numwritten; +} + +static void write_debugfs(int pid, uint64_t vaddr_start, uint64_t vaddr_end) +{ + char input[INPUT_MAX]; + int ret; + + ret = snprintf(input, INPUT_MAX, "%d,0x%lx,0x%lx", pid, vaddr_start, + vaddr_end); + if (ret >= INPUT_MAX) { + printf("%s: Debugfs input is too long\n", __func__); + exit(EXIT_FAILURE); + } + + if (!write_file(SPLIT_DEBUGFS, input, ret + 1)) { + perror(SPLIT_DEBUGFS); + exit(EXIT_FAILURE); + } +} + +#define MAX_LINE_LENGTH 500 + +static bool check_for_pattern(FILE *fp, const char *pattern, char *buf) +{ + while (fgets(buf, MAX_LINE_LENGTH, fp) != NULL) { + if (!strncmp(buf, pattern, strlen(pattern))) + return true; + } + return false; +} + +static uint64_t check_huge(void *addr) +{ + uint64_t thp = 0; + int ret; + FILE *fp; + char buffer[MAX_LINE_LENGTH]; + char addr_pattern[MAX_LINE_LENGTH]; + + ret = snprintf(addr_pattern, MAX_LINE_LENGTH, "%08lx-", + (unsigned long) addr); + if (ret >= MAX_LINE_LENGTH) { + printf("%s: Pattern is too long\n", __func__); + exit(EXIT_FAILURE); + } + + + fp = fopen(SMAP_PATH, "r"); + if (!fp) { + printf("%s: Failed to open file %s\n", __func__, SMAP_PATH); + exit(EXIT_FAILURE); + } + if (!check_for_pattern(fp, addr_pattern, buffer)) + goto err_out; + + /* + * Fetch the AnonHugePages: in the same block and check the number of + * hugepages. + */ + if (!check_for_pattern(fp, "AnonHugePages:", buffer)) + goto err_out; + + if (sscanf(buffer, "AnonHugePages:%10ld kB", &thp) != 1) { + printf("Reading smap error\n"); + exit(EXIT_FAILURE); + } + +err_out: + fclose(fp); + return thp; +} + +void split_pmd_thp(void) +{ + char *one_page; + size_t len = 4 * pmd_pagesize; + uint64_t thp_size; + size_t i; + + one_page = memalign(pmd_pagesize, len); + + if (!one_page) { + printf("Fail to allocate memory\n"); + exit(EXIT_FAILURE); + } + + madvise(one_page, len, MADV_HUGEPAGE); + + for (i = 0; i < len; i++) + one_page[i] = (char)i; + + thp_size = check_huge(one_page); + if (!thp_size) { + printf("No THP is allocated\n"); + exit(EXIT_FAILURE); + } + + /* split all THPs */ + write_debugfs(getpid(), (uint64_t)one_page, (uint64_t)one_page + len); + + for (i = 0; i < len; i++) + if (one_page[i] != (char)i) { + printf("%ld byte corrupted\n", i); + exit(EXIT_FAILURE); + } + + + thp_size = check_huge(one_page); + if (thp_size) { + printf("Still %ld kB AnonHugePages not split\n", thp_size); + exit(EXIT_FAILURE); + } + + printf("Split huge pages successful\n"); + free(one_page); +} + +void split_pte_mapped_thp(void) +{ + char *one_page, *pte_mapped, *pte_mapped2; + size_t len = 4 * pmd_pagesize; + uint64_t thp_size; + size_t i; + const char *pagemap_template = "/proc/%d/pagemap"; + const char *kpageflags_proc = "/proc/kpageflags"; + char pagemap_proc[255]; + int pagemap_fd; + int kpageflags_fd; + + if (snprintf(pagemap_proc, 255, pagemap_template, getpid()) < 0) { + perror("get pagemap proc error"); + exit(EXIT_FAILURE); + } + pagemap_fd = open(pagemap_proc, O_RDONLY); + + if (pagemap_fd == -1) { + perror("read pagemap:"); + exit(EXIT_FAILURE); + } + + kpageflags_fd = open(kpageflags_proc, O_RDONLY); + + if (kpageflags_fd == -1) { + perror("read kpageflags:"); + exit(EXIT_FAILURE); + } + + one_page = mmap((void *)(1UL << 30), len, PROT_READ | PROT_WRITE, + MAP_ANONYMOUS | MAP_PRIVATE, -1, 0); + + madvise(one_page, len, MADV_HUGEPAGE); + + for (i = 0; i < len; i++) + one_page[i] = (char)i; + + thp_size = check_huge(one_page); + if (!thp_size) { + printf("No THP is allocated\n"); + exit(EXIT_FAILURE); + } + + /* remap the first pagesize of first THP */ + pte_mapped = mremap(one_page, pagesize, pagesize, MREMAP_MAYMOVE); + + /* remap the Nth pagesize of Nth THP */ + for (i = 1; i < 4; i++) { + pte_mapped2 = mremap(one_page + pmd_pagesize * i + pagesize * i, + pagesize, pagesize, + MREMAP_MAYMOVE|MREMAP_FIXED, + pte_mapped + pagesize * i); + if (pte_mapped2 == (char *)-1) { + perror("mremap failed"); + exit(EXIT_FAILURE); + } + } + + /* smap does not show THPs after mremap, use kpageflags instead */ + thp_size = 0; + for (i = 0; i < pagesize * 4; i++) + if (i % pagesize == 0 && + is_backed_by_thp(&pte_mapped[i], pagemap_fd, kpageflags_fd)) + thp_size++; + + if (thp_size != 4) { + printf("Some THPs are missing during mremap\n"); + exit(EXIT_FAILURE); + } + + /* split all remapped THPs */ + write_debugfs(getpid(), (uint64_t)pte_mapped, + (uint64_t)pte_mapped + pagesize * 4); + + /* smap does not show THPs after mremap, use kpageflags instead */ + thp_size = 0; + for (i = 0; i < pagesize * 4; i++) { + if (pte_mapped[i] != (char)i) { + printf("%ld byte corrupted\n", i); + exit(EXIT_FAILURE); + } + if (i % pagesize == 0 && + is_backed_by_thp(&pte_mapped[i], pagemap_fd, kpageflags_fd)) + thp_size++; + } + + if (thp_size) { + printf("Still %ld THPs not split\n", thp_size); + exit(EXIT_FAILURE); + } + + printf("Split PTE-mapped huge pages successful\n"); + munmap(one_page, len); + close(pagemap_fd); + close(kpageflags_fd); +} + +int main(int argc, char **argv) +{ + if (geteuid() != 0) { + printf("Please run the benchmark as root\n"); + exit(EXIT_FAILURE); + } + + pagesize = getpagesize(); + pageshift = ffs(pagesize) - 1; + pmd_pagesize = read_pmd_pagesize(); + + split_pmd_thp(); + split_pte_mapped_thp(); + + return 0; +} -- 2.30.2

4 years, 3 months

1
1
0 0

[PATCH] memfd_secret: use unsigned int rather than long as syscall flags type

by Mike Rapoport

From: Mike Rapoport <rppt(a)linux.ibm.com> Yuri Norov says: If parameter size is the same for native and compat ABIs, we may wire a syscall made by compat client to native handler. This is true for unsigned int, but not true for unsigned long or pointer. That's why I suggest using unsigned int and so avoid creating compat entry point. Use unsigned int as the type of the flags parameter in memfd_secret() system call. Signed-off-by: Mike Rapoport <rppt(a)linux.ibm.com> --- @Andrew, The patch is vs v5.12-rc5-mmots-2021-03-30-23, I'd appreciate if it would be added as a fixup to the memfd_secret series. include/linux/syscalls.h | 2 +- mm/secretmem.c | 2 +- tools/testing/selftests/vm/memfd_secret.c | 2 +- 3 files changed, 3 insertions(+), 3 deletions(-) diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h index 49c93c906893..1a1b5d724497 100644 --- a/include/linux/syscalls.h +++ b/include/linux/syscalls.h @@ -1050,7 +1050,7 @@ asmlinkage long sys_landlock_create_ruleset(const struct landlock_ruleset_attr _ asmlinkage long sys_landlock_add_rule(int ruleset_fd, enum landlock_rule_type rule_type, const void __user *rule_attr, __u32 flags); asmlinkage long sys_landlock_restrict_self(int ruleset_fd, __u32 flags); -asmlinkage long sys_memfd_secret(unsigned long flags); +asmlinkage long sys_memfd_secret(unsigned int flags); /* * Architecture-specific system calls diff --git a/mm/secretmem.c b/mm/secretmem.c index f2ae3f32a193..3b1ba3991964 100644 --- a/mm/secretmem.c +++ b/mm/secretmem.c @@ -199,7 +199,7 @@ static struct file *secretmem_file_create(unsigned long flags) return file; } -SYSCALL_DEFINE1(memfd_secret, unsigned long, flags) +SYSCALL_DEFINE1(memfd_secret, unsigned int, flags) { struct file *file; int fd, err; diff --git a/tools/testing/selftests/vm/memfd_secret.c b/tools/testing/selftests/vm/memfd_secret.c index c878c2b841fc..2462f52e9c96 100644 --- a/tools/testing/selftests/vm/memfd_secret.c +++ b/tools/testing/selftests/vm/memfd_secret.c @@ -38,7 +38,7 @@ static unsigned long page_size; static unsigned long mlock_limit_cur; static unsigned long mlock_limit_max; -static int memfd_secret(unsigned long flags) +static int memfd_secret(unsigned int flags) { return syscall(__NR_memfd_secret, flags); } -- 2.28.0

4 years, 3 months

3
2
0 0

[PATCH] selftests/bpf: add LDFLAGS when building test_verifier

by Jisheng Zhang

From: Jisheng Zhang <jszhang(a)kernel.org> This is useful for cross compile process to point linker to the correct libelf, libcap, libz path. Signed-off-by: Jisheng Zhang <jszhang(a)kernel.org> --- tools/testing/selftests/bpf/Makefile | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile index 044bfdcf5b74..dac1c5094e28 100644 --- a/tools/testing/selftests/bpf/Makefile +++ b/tools/testing/selftests/bpf/Makefile @@ -447,7 +447,7 @@ verifier/tests.h: verifier/*.c ) > verifier/tests.h) $(OUTPUT)/test_verifier: test_verifier.c verifier/tests.h $(BPFOBJ) | $(OUTPUT) $(call msg,BINARY,,$@) - $(Q)$(CC) $(CFLAGS) $(filter %.a %.o %.c,$^) $(LDLIBS) -o $@ + $(Q)$(CC) $(CFLAGS) $(LDFLAGS) $(filter %.a %.o %.c,$^) $(LDLIBS) -o $@ # Make sure we are able to include and link libbpf against c++. $(OUTPUT)/test_cpp: test_cpp.cpp $(OUTPUT)/test_core_extern.skel.h $(BPFOBJ) -- 2.31.0

4 years, 3 months

3
2
0 0

[PATCH v7 1/2] mm: huge_memory: a new debugfs interface for splitting THP tests.

by Zi Yan

From: Zi Yan <ziy(a)nvidia.com> We did not have a direct user interface of splitting the compound page backing a THP and there is no need unless we want to expose the THP implementation details to users. Make <debugfs>/split_huge_pages accept a new command to do that. By writing "<pid>,<vaddr_start>,<vaddr_end>" to <debugfs>/split_huge_pages, THPs within the given virtual address range from the process with the given pid are split. It is used to test split_huge_page function. In addition, a selftest program is added to tools/testing/selftests/vm to utilize the interface by splitting PMD THPs and PTE-mapped THPs. This does not change the old behavior, i.e., writing 1 to the interface to split all THPs in the system. Changelog: >From v6: 1. pr_info -> pr_debug. 2. Added cond_resched() in all split loops. (suggested by David Rientjes) >From v5: 1. Skipped special VMAs and other fixes. (suggested by Yang Shi) >From v4: 1. Fixed the error code return issue, spotted by kernel test robot <lkp(a)intel.com>. >From v3: 1. Factored out split huge pages in the given pid code to a separate function. 2. Added the missing put_page for not split pages. 3. pr_debug -> pr_info, make reading results simpler. >From v2: 1. Reused existing <debugfs>/split_huge_pages interface. (suggested by Yang Shi) >From v1: 1. Removed unnecessary calling to vma_migratable, spotted by kernel test robot <lkp(a)intel.com>. 2. Dropped the use of find_mm_struct and code it directly, since there is no need for the permission check in that function and the function is only available when migration is on. 3. Added some comments in the selftest program to clarify how PTE-mapped THPs are formed. Signed-off-by: Zi Yan <ziy(a)nvidia.com> Reviewed-by: Yang Shi <shy828301(a)gmail.com> --- mm/huge_memory.c | 155 ++++++++- tools/testing/selftests/vm/.gitignore | 1 + tools/testing/selftests/vm/Makefile | 1 + .../selftests/vm/split_huge_page_test.c | 318 ++++++++++++++++++ 4 files changed, 467 insertions(+), 8 deletions(-) create mode 100644 tools/testing/selftests/vm/split_huge_page_test.c diff --git a/mm/huge_memory.c b/mm/huge_memory.c index 8eba529a0f17..1bcab247aea8 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -7,6 +7,7 @@ #include <linux/mm.h> #include <linux/sched.h> +#include <linux/sched/mm.h> #include <linux/sched/coredump.h> #include <linux/sched/numa_balancing.h> #include <linux/highmem.h> @@ -2927,16 +2928,14 @@ static struct shrinker deferred_split_shrinker = { }; #ifdef CONFIG_DEBUG_FS -static int split_huge_pages_set(void *data, u64 val) +static void split_huge_pages_all(void) { struct zone *zone; struct page *page; unsigned long pfn, max_zone_pfn; unsigned long total = 0, split = 0; - if (val != 1) - return -EINVAL; - + pr_debug("Split all THPs\n"); for_each_populated_zone(zone) { max_zone_pfn = zone_end_pfn(zone); for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++) { @@ -2960,15 +2959,155 @@ static int split_huge_pages_set(void *data, u64 val) unlock_page(page); next: put_page(page); + cond_resched(); } } - pr_info("%lu of %lu THP split\n", split, total); + pr_debug("%lu of %lu THP split\n", split, total); +} - return 0; +static inline bool vma_not_suitable_for_thp_split(struct vm_area_struct *vma) +{ + return vma_is_special_huge(vma) || (vma->vm_flags & VM_IO) || + is_vm_hugetlb_page(vma); +} + +static int split_huge_pages_pid(int pid, unsigned long vaddr_start, + unsigned long vaddr_end) +{ + int ret = 0; + struct task_struct *task; + struct mm_struct *mm; + unsigned long total = 0, split = 0; + unsigned long addr; + + vaddr_start &= PAGE_MASK; + vaddr_end &= PAGE_MASK; + + /* Find the task_struct from pid */ + rcu_read_lock(); + task = find_task_by_vpid(pid); + if (!task) { + rcu_read_unlock(); + ret = -ESRCH; + goto out; + } + get_task_struct(task); + rcu_read_unlock(); + + /* Find the mm_struct */ + mm = get_task_mm(task); + put_task_struct(task); + + if (!mm) { + ret = -EINVAL; + goto out; + } + + pr_debug("Split huge pages in pid: %d, vaddr: [0x%lx - 0x%lx]\n", + pid, vaddr_start, vaddr_end); + + mmap_read_lock(mm); + /* + * always increase addr by PAGE_SIZE, since we could have a PTE page + * table filled with PTE-mapped THPs, each of which is distinct. + */ + for (addr = vaddr_start; addr < vaddr_end; addr += PAGE_SIZE) { + struct vm_area_struct *vma = find_vma(mm, addr); + unsigned int follflags; + struct page *page; + + if (!vma || addr < vma->vm_start) + break; + + /* skip special VMA and hugetlb VMA */ + if (vma_not_suitable_for_thp_split(vma)) { + addr = vma->vm_end; + continue; + } + + /* FOLL_DUMP to ignore special (like zero) pages */ + follflags = FOLL_GET | FOLL_DUMP; + page = follow_page(vma, addr, follflags); + + if (IS_ERR(page)) + continue; + if (!page) + continue; + + if (!is_transparent_hugepage(page)) + goto next; + + total++; + if (!can_split_huge_page(compound_head(page), NULL)) + goto next; + + if (!trylock_page(page)) + goto next; + + if (!split_huge_page(page)) + split++; + + unlock_page(page); +next: + put_page(page); + cond_resched(); + } + mmap_read_unlock(mm); + mmput(mm); + + pr_debug("%lu of %lu THP split\n", split, total); + +out: + return ret; } -DEFINE_DEBUGFS_ATTRIBUTE(split_huge_pages_fops, NULL, split_huge_pages_set, - "%llu\n"); + +#define MAX_INPUT_BUF_SZ 255 + +static ssize_t split_huge_pages_write(struct file *file, const char __user *buf, + size_t count, loff_t *ppops) +{ + static DEFINE_MUTEX(split_debug_mutex); + ssize_t ret; + char input_buf[MAX_INPUT_BUF_SZ]; /* hold pid, start_vaddr, end_vaddr */ + int pid; + unsigned long vaddr_start, vaddr_end; + + ret = mutex_lock_interruptible(&split_debug_mutex); + if (ret) + return ret; + + ret = -EFAULT; + + memset(input_buf, 0, MAX_INPUT_BUF_SZ); + if (copy_from_user(input_buf, buf, min_t(size_t, count, MAX_INPUT_BUF_SZ))) + goto out; + + input_buf[MAX_INPUT_BUF_SZ - 1] = '\0'; + ret = sscanf(input_buf, "%d,0x%lx,0x%lx", &pid, &vaddr_start, &vaddr_end); + if (ret == 1 && pid == 1) { + split_huge_pages_all(); + ret = strlen(input_buf); + goto out; + } else if (ret != 3) { + ret = -EINVAL; + goto out; + } + + ret = split_huge_pages_pid(pid, vaddr_start, vaddr_end); + if (!ret) + ret = strlen(input_buf); +out: + mutex_unlock(&split_debug_mutex); + return ret; + +} + +static const struct file_operations split_huge_pages_fops = { + .owner = THIS_MODULE, + .write = split_huge_pages_write, + .llseek = no_llseek, +}; static int __init split_huge_pages_debugfs(void) { diff --git a/tools/testing/selftests/vm/.gitignore b/tools/testing/selftests/vm/.gitignore index c8deddc81e7a..da92ded5a27c 100644 --- a/tools/testing/selftests/vm/.gitignore +++ b/tools/testing/selftests/vm/.gitignore @@ -23,3 +23,4 @@ write_to_hugetlbfs hmm-tests memfd_secret local_config.* +split_huge_page_test diff --git a/tools/testing/selftests/vm/Makefile b/tools/testing/selftests/vm/Makefile index 38e25b90f8bf..266580ea938c 100644 --- a/tools/testing/selftests/vm/Makefile +++ b/tools/testing/selftests/vm/Makefile @@ -43,6 +43,7 @@ TEST_GEN_FILES += on-fault-limit TEST_GEN_FILES += thuge-gen TEST_GEN_FILES += transhuge-stress TEST_GEN_FILES += userfaultfd +TEST_GEN_FILES += split_huge_page_test ifeq ($(MACHINE),x86_64) CAN_BUILD_I386 := $(shell ./../x86/check_cc.sh $(CC) ../x86/trivial_32bit_program.c -m32) diff --git a/tools/testing/selftests/vm/split_huge_page_test.c b/tools/testing/selftests/vm/split_huge_page_test.c new file mode 100644 index 000000000000..2c0c18e60c57 --- /dev/null +++ b/tools/testing/selftests/vm/split_huge_page_test.c @@ -0,0 +1,318 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * A test of splitting PMD THPs and PTE-mapped THPs from a specified virtual + * address range in a process via <debugfs>/split_huge_pages interface. + */ + +#define _GNU_SOURCE +#include <stdio.h> +#include <stdlib.h> +#include <unistd.h> +#include <inttypes.h> +#include <string.h> +#include <fcntl.h> +#include <sys/mman.h> +#include <malloc.h> +#include <stdbool.h> + +uint64_t pagesize; +unsigned int pageshift; +uint64_t pmd_pagesize; + +#define PMD_SIZE_PATH "/sys/kernel/mm/transparent_hugepage/hpage_pmd_size" +#define SPLIT_DEBUGFS "/sys/kernel/debug/split_huge_pages" +#define SMAP_PATH "/proc/self/smaps" +#define INPUT_MAX 80 + +#define PFN_MASK ((1UL<<55)-1) +#define KPF_THP (1UL<<22) + +int is_backed_by_thp(char *vaddr, int pagemap_file, int kpageflags_file) +{ + uint64_t paddr; + uint64_t page_flags; + + if (pagemap_file) { + pread(pagemap_file, &paddr, sizeof(paddr), + ((long)vaddr >> pageshift) * sizeof(paddr)); + + if (kpageflags_file) { + pread(kpageflags_file, &page_flags, sizeof(page_flags), + (paddr & PFN_MASK) * sizeof(page_flags)); + + return !!(page_flags & KPF_THP); + } + } + return 0; +} + + +static uint64_t read_pmd_pagesize(void) +{ + int fd; + char buf[20]; + ssize_t num_read; + + fd = open(PMD_SIZE_PATH, O_RDONLY); + if (fd == -1) { + perror("Open hpage_pmd_size failed"); + exit(EXIT_FAILURE); + } + num_read = read(fd, buf, 19); + if (num_read < 1) { + close(fd); + perror("Read hpage_pmd_size failed"); + exit(EXIT_FAILURE); + } + buf[num_read] = '\0'; + close(fd); + + return strtoul(buf, NULL, 10); +} + +static int write_file(const char *path, const char *buf, size_t buflen) +{ + int fd; + ssize_t numwritten; + + fd = open(path, O_WRONLY); + if (fd == -1) + return 0; + + numwritten = write(fd, buf, buflen - 1); + close(fd); + if (numwritten < 1) + return 0; + + return (unsigned int) numwritten; +} + +static void write_debugfs(int pid, uint64_t vaddr_start, uint64_t vaddr_end) +{ + char input[INPUT_MAX]; + int ret; + + ret = snprintf(input, INPUT_MAX, "%d,0x%lx,0x%lx", pid, vaddr_start, + vaddr_end); + if (ret >= INPUT_MAX) { + printf("%s: Debugfs input is too long\n", __func__); + exit(EXIT_FAILURE); + } + + if (!write_file(SPLIT_DEBUGFS, input, ret + 1)) { + perror(SPLIT_DEBUGFS); + exit(EXIT_FAILURE); + } +} + +#define MAX_LINE_LENGTH 500 + +static bool check_for_pattern(FILE *fp, const char *pattern, char *buf) +{ + while (fgets(buf, MAX_LINE_LENGTH, fp) != NULL) { + if (!strncmp(buf, pattern, strlen(pattern))) + return true; + } + return false; +} + +static uint64_t check_huge(void *addr) +{ + uint64_t thp = 0; + int ret; + FILE *fp; + char buffer[MAX_LINE_LENGTH]; + char addr_pattern[MAX_LINE_LENGTH]; + + ret = snprintf(addr_pattern, MAX_LINE_LENGTH, "%08lx-", + (unsigned long) addr); + if (ret >= MAX_LINE_LENGTH) { + printf("%s: Pattern is too long\n", __func__); + exit(EXIT_FAILURE); + } + + + fp = fopen(SMAP_PATH, "r"); + if (!fp) { + printf("%s: Failed to open file %s\n", __func__, SMAP_PATH); + exit(EXIT_FAILURE); + } + if (!check_for_pattern(fp, addr_pattern, buffer)) + goto err_out; + + /* + * Fetch the AnonHugePages: in the same block and check the number of + * hugepages. + */ + if (!check_for_pattern(fp, "AnonHugePages:", buffer)) + goto err_out; + + if (sscanf(buffer, "AnonHugePages:%10ld kB", &thp) != 1) { + printf("Reading smap error\n"); + exit(EXIT_FAILURE); + } + +err_out: + fclose(fp); + return thp; +} + +void split_pmd_thp(void) +{ + char *one_page; + size_t len = 4 * pmd_pagesize; + uint64_t thp_size; + size_t i; + + one_page = memalign(pmd_pagesize, len); + + if (!one_page) { + printf("Fail to allocate memory\n"); + exit(EXIT_FAILURE); + } + + madvise(one_page, len, MADV_HUGEPAGE); + + for (i = 0; i < len; i++) + one_page[i] = (char)i; + + thp_size = check_huge(one_page); + if (!thp_size) { + printf("No THP is allocated\n"); + exit(EXIT_FAILURE); + } + + /* split all THPs */ + write_debugfs(getpid(), (uint64_t)one_page, (uint64_t)one_page + len); + + for (i = 0; i < len; i++) + if (one_page[i] != (char)i) { + printf("%ld byte corrupted\n", i); + exit(EXIT_FAILURE); + } + + + thp_size = check_huge(one_page); + if (thp_size) { + printf("Still %ld kB AnonHugePages not split\n", thp_size); + exit(EXIT_FAILURE); + } + + printf("Split huge pages successful\n"); + free(one_page); +} + +void split_pte_mapped_thp(void) +{ + char *one_page, *pte_mapped, *pte_mapped2; + size_t len = 4 * pmd_pagesize; + uint64_t thp_size; + size_t i; + const char *pagemap_template = "/proc/%d/pagemap"; + const char *kpageflags_proc = "/proc/kpageflags"; + char pagemap_proc[255]; + int pagemap_fd; + int kpageflags_fd; + + if (snprintf(pagemap_proc, 255, pagemap_template, getpid()) < 0) { + perror("get pagemap proc error"); + exit(EXIT_FAILURE); + } + pagemap_fd = open(pagemap_proc, O_RDONLY); + + if (pagemap_fd == -1) { + perror("read pagemap:"); + exit(EXIT_FAILURE); + } + + kpageflags_fd = open(kpageflags_proc, O_RDONLY); + + if (kpageflags_fd == -1) { + perror("read kpageflags:"); + exit(EXIT_FAILURE); + } + + one_page = mmap((void *)(1UL << 30), len, PROT_READ | PROT_WRITE, + MAP_ANONYMOUS | MAP_PRIVATE, -1, 0); + + madvise(one_page, len, MADV_HUGEPAGE); + + for (i = 0; i < len; i++) + one_page[i] = (char)i; + + thp_size = check_huge(one_page); + if (!thp_size) { + printf("No THP is allocated\n"); + exit(EXIT_FAILURE); + } + + /* remap the first pagesize of first THP */ + pte_mapped = mremap(one_page, pagesize, pagesize, MREMAP_MAYMOVE); + + /* remap the Nth pagesize of Nth THP */ + for (i = 1; i < 4; i++) { + pte_mapped2 = mremap(one_page + pmd_pagesize * i + pagesize * i, + pagesize, pagesize, + MREMAP_MAYMOVE|MREMAP_FIXED, + pte_mapped + pagesize * i); + if (pte_mapped2 == (char *)-1) { + perror("mremap failed"); + exit(EXIT_FAILURE); + } + } + + /* smap does not show THPs after mremap, use kpageflags instead */ + thp_size = 0; + for (i = 0; i < pagesize * 4; i++) + if (i % pagesize == 0 && + is_backed_by_thp(&pte_mapped[i], pagemap_fd, kpageflags_fd)) + thp_size++; + + if (thp_size != 4) { + printf("Some THPs are missing during mremap\n"); + exit(EXIT_FAILURE); + } + + /* split all remapped THPs */ + write_debugfs(getpid(), (uint64_t)pte_mapped, + (uint64_t)pte_mapped + pagesize * 4); + + /* smap does not show THPs after mremap, use kpageflags instead */ + thp_size = 0; + for (i = 0; i < pagesize * 4; i++) { + if (pte_mapped[i] != (char)i) { + printf("%ld byte corrupted\n", i); + exit(EXIT_FAILURE); + } + if (i % pagesize == 0 && + is_backed_by_thp(&pte_mapped[i], pagemap_fd, kpageflags_fd)) + thp_size++; + } + + if (thp_size) { + printf("Still %ld THPs not split\n", thp_size); + exit(EXIT_FAILURE); + } + + printf("Split PTE-mapped huge pages successful\n"); + munmap(one_page, len); + close(pagemap_fd); + close(kpageflags_fd); +} + +int main(int argc, char **argv) +{ + if (geteuid() != 0) { + printf("Please run the benchmark as root\n"); + exit(EXIT_FAILURE); + } + + pagesize = getpagesize(); + pageshift = ffs(pagesize) - 1; + pmd_pagesize = read_pmd_pagesize(); + + split_pmd_thp(); + split_pte_mapped_thp(); + + return 0; +} -- 2.30.2

4 years, 3 months

3
3
0 0

[PATCH v3 00/11] Add support for synchronous signals on perf events

by Marco Elver

The perf subsystem today unifies various tracing and monitoring features, from both software and hardware. One benefit of the perf subsystem is automatically inheriting events to child tasks, which enables process-wide events monitoring with low overheads. By default perf events are non-intrusive, not affecting behaviour of the tasks being monitored. For certain use-cases, however, it makes sense to leverage the generality of the perf events subsystem and optionally allow the tasks being monitored to receive signals on events they are interested in. This patch series adds the option to synchronously signal user space on events. To better support process-wide synchronous self-monitoring, without events propagating to children that do not share the current process's shared environment, two pre-requisite patches are added to optionally restrict inheritance to CLONE_THREAD, and remove events on exec (without affecting the parent). Examples how to use these features can be found in the tests added at the end of the series. In addition to the tests added, the series has also been subjected to syzkaller fuzzing (focus on 'kernel/events/' coverage). Motivation and Example Uses --------------------------- 1. Our immediate motivation is low-overhead sampling-based race detection for user space [1]. By using perf_event_open() at process initialization, we can create hardware breakpoint/watchpoint events that are propagated automatically to all threads in a process. As far as we are aware, today no existing kernel facility (such as ptrace) allows us to set up process-wide watchpoints with minimal overheads (that are comparable to mprotect() of whole pages). 2. Other low-overhead error detectors that rely on detecting accesses to certain memory locations or code, process-wide and also only in a specific set of subtasks or threads. [1] https://llvm.org/devmtg/2020-09/slides/Morehouse-GWP-Tsan.pdf Other ideas for use-cases we found interesting, but should only illustrate the range of potential to further motivate the utility (we're sure there are more): 3. Code hot patching without full stop-the-world. Specifically, by setting a code breakpoint to entry to the patched routine, then send signals to threads and check that they are not in the routine, but without stopping them further. If any of the threads will enter the routine, it will receive SIGTRAP and pause. 4. Safepoints without mprotect(). Some Java implementations use "load from a known memory location" as a safepoint. When threads need to be stopped, the page containing the location is mprotect()ed and threads get a signal. This could be replaced with a watchpoint, which does not require a whole page nor DTLB shootdowns. 5. Threads receiving signals on performance events to throttle/unthrottle themselves. 6. Tracking data flow globally. Changelog --------- v3: * Add patch "perf: Rework perf_event_exit_event()" to beginning of series, courtesy of Peter Zijlstra. * Rework "perf: Add support for event removal on exec" based on the added "perf: Rework perf_event_exit_event()". * Fix kselftests to work with more recent libc, due to the way it forces using the kernel's own siginfo_t. * Add basic perf-tool built-in test. v2/RFC: https://lkml.kernel.org/r/20210310104139.679618-1-elver@google.com * Patch "Support only inheriting events if cloned with CLONE_THREAD" added to series. * Patch "Add support for event removal on exec" added to series. * Patch "Add kselftest for process-wide sigtrap handling" added to series. * Patch "Add kselftest for remove_on_exec" added to series. * Implicitly restrict inheriting events if sigtrap, but the child was cloned with CLONE_CLEAR_SIGHAND, because it is not generally safe if the child cleared all signal handlers to continue sending SIGTRAP. * Various minor fixes (see details in patches). v1/RFC: https://lkml.kernel.org/r/20210223143426.2412737-1-elver@google.com Pre-series: The discussion at [2] led to the changes in this series. The approach taken in "Add support for SIGTRAP on perf events" to trigger the signal was suggested by Peter Zijlstra in [3]. [2] https://lore.kernel.org/lkml/CACT4Y+YPrXGw+AtESxAgPyZ84TYkNZdP0xpocX2jwVAbZ… [3] https://lore.kernel.org/lkml/YBv3rAT566k+6zjg@hirez.programming.kicks-ass.n… Marco Elver (10): perf: Apply PERF_EVENT_IOC_MODIFY_ATTRIBUTES to children perf: Support only inheriting events if cloned with CLONE_THREAD perf: Add support for event removal on exec signal: Introduce TRAP_PERF si_code and si_perf to siginfo perf: Add support for SIGTRAP on perf events perf: Add breakpoint information to siginfo on SIGTRAP selftests/perf_events: Add kselftest for process-wide sigtrap handling selftests/perf_events: Add kselftest for remove_on_exec tools headers uapi: Sync tools/include/uapi/linux/perf_event.h perf test: Add basic stress test for sigtrap handling Peter Zijlstra (1): perf: Rework perf_event_exit_event() arch/m68k/kernel/signal.c | 3 + arch/x86/kernel/signal_compat.c | 5 +- fs/signalfd.c | 4 + include/linux/compat.h | 2 + include/linux/perf_event.h | 6 +- include/linux/signal.h | 1 + include/uapi/asm-generic/siginfo.h | 6 +- include/uapi/linux/perf_event.h | 5 +- include/uapi/linux/signalfd.h | 4 +- kernel/events/core.c | 297 +++++++++++++----- kernel/fork.c | 2 +- kernel/signal.c | 11 + tools/include/uapi/linux/perf_event.h | 5 +- tools/perf/tests/Build | 1 + tools/perf/tests/builtin-test.c | 5 + tools/perf/tests/sigtrap.c | 148 +++++++++ tools/perf/tests/tests.h | 1 + .../testing/selftests/perf_events/.gitignore | 3 + tools/testing/selftests/perf_events/Makefile | 6 + tools/testing/selftests/perf_events/config | 1 + .../selftests/perf_events/remove_on_exec.c | 260 +++++++++++++++ tools/testing/selftests/perf_events/settings | 1 + .../selftests/perf_events/sigtrap_threads.c | 206 ++++++++++++ 23 files changed, 896 insertions(+), 87 deletions(-) create mode 100644 tools/perf/tests/sigtrap.c create mode 100644 tools/testing/selftests/perf_events/.gitignore create mode 100644 tools/testing/selftests/perf_events/Makefile create mode 100644 tools/testing/selftests/perf_events/config create mode 100644 tools/testing/selftests/perf_events/remove_on_exec.c create mode 100644 tools/testing/selftests/perf_events/settings create mode 100644 tools/testing/selftests/perf_events/sigtrap_threads.c -- 2.31.0.291.g576ba9dcdaf-goog

4 years, 3 months

5
38
0 0

[PATCH v3] userfaultfd/shmem: fix MCOPY_ATOMIC_CONTNUE behavior

by Axel Rasmussen

Previously, we shared too much of the code with COPY and ZEROPAGE, so we manipulated things in various invalid ways: - Previously, we unconditionally called shmem_inode_acct_block. In the continue case, we're looking up an existing page which would have been accounted for properly when it was allocated. So doing it twice results in double-counting, and eventually leaking. - Previously, we made the pte writable whenever the VMA was writable. However, for continue, consider this case: 1. A tmpfs file was created 2. The non-UFFD-registered side mmap()-s with MAP_SHARED 3. The UFFD-registered side mmap()-s with MAP_PRIVATE In this case, even though the UFFD-registered VMA may be writable, we still want CoW behavior. So, check for this case and don't make the pte writable. - The initial pgoff / max_off check isn't necessary, so we can skip past it. The second one seems likely to be unnecessary too, but keep it just in case. Modify both checks to use pgoff, as offset is equivalent and not needed. - Previously, we unconditionally called ClearPageDirty() in the error path. In the continue case though, since this is an existing page, it might have already been dirty before we started touching it. It's very problematic to clear the bit incorrectly, but not a problem to leave it - so, just omit the ClearPageDirty() entirely. - Previously, we unconditionally removed the page from the page cache in the error path. But in the continue case, we didn't add it - it was already there because the page is present in some second (non-UFFD-registered) mapping. So, removing it is invalid. Because the error handling issues are easy to exercise in the selftest, make a small modification there to do so. Finally, refactor shmem_mcopy_atomic_pte a bit. By this point, we've added a lot of "if (!is_continue)"-s everywhere. It's cleaner to just check for that mode first thing, and then "goto" down to where the parts we actually want are. This leaves the code in between cleaner. Changes since v2: - Drop the ClearPageDirty() entirely, instead of trying to remember the old value. - Modify both pgoff / max_off checks to use pgoff. It's equivalent to offset, but offset wasn't initialized until the first check (which we're skipping). - Keep the second pgoff / max_off check in the continue case. Changes since v1: - Refactor to skip ahead with goto, instead of adding several more "if (!is_continue)". - Fix unconditional ClearPageDirty(). - Don't pte_mkwrite() when is_continue && !VM_SHARED. Fixes: 00da60b9d0a0 ("userfaultfd: support minor fault handling for shmem") Signed-off-by: Axel Rasmussen <axelrasmussen(a)google.com> --- mm/shmem.c | 60 +++++++++++++----------- tools/testing/selftests/vm/userfaultfd.c | 12 +++++ 2 files changed, 44 insertions(+), 28 deletions(-) diff --git a/mm/shmem.c b/mm/shmem.c index d2e0e81b7d2e..fbcce850a16e 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -2377,18 +2377,22 @@ int shmem_mcopy_atomic_pte(struct mm_struct *dst_mm, pmd_t *dst_pmd, struct page *page; pte_t _dst_pte, *dst_pte; int ret; - pgoff_t offset, max_off; - - ret = -ENOMEM; - if (!shmem_inode_acct_block(inode, 1)) - goto out; + pgoff_t max_off; + int writable; if (is_continue) { ret = -EFAULT; page = find_lock_page(mapping, pgoff); if (!page) - goto out_unacct_blocks; - } else if (!*pagep) { + goto out; + goto install_ptes; + } + + ret = -ENOMEM; + if (!shmem_inode_acct_block(inode, 1)) + goto out; + + if (!*pagep) { page = shmem_alloc_page(gfp, info, pgoff); if (!page) goto out_unacct_blocks; @@ -2415,30 +2419,29 @@ int shmem_mcopy_atomic_pte(struct mm_struct *dst_mm, pmd_t *dst_pmd, *pagep = NULL; } - if (!is_continue) { - VM_BUG_ON(PageSwapBacked(page)); - VM_BUG_ON(PageLocked(page)); - __SetPageLocked(page); - __SetPageSwapBacked(page); - __SetPageUptodate(page); - } + VM_BUG_ON(PageSwapBacked(page)); + VM_BUG_ON(PageLocked(page)); + __SetPageLocked(page); + __SetPageSwapBacked(page); + __SetPageUptodate(page); ret = -EFAULT; - offset = linear_page_index(dst_vma, dst_addr); max_off = DIV_ROUND_UP(i_size_read(inode), PAGE_SIZE); - if (unlikely(offset >= max_off)) + if (unlikely(pgoff >= max_off)) goto out_release; - /* If page wasn't already in the page cache, add it. */ - if (!is_continue) { - ret = shmem_add_to_page_cache(page, mapping, pgoff, NULL, - gfp & GFP_RECLAIM_MASK, dst_mm); - if (ret) - goto out_release; - } + ret = shmem_add_to_page_cache(page, mapping, pgoff, NULL, + gfp & GFP_RECLAIM_MASK, dst_mm); + if (ret) + goto out_release; +install_ptes: _dst_pte = mk_pte(page, dst_vma->vm_page_prot); - if (dst_vma->vm_flags & VM_WRITE) + /* For CONTINUE on a non-shared VMA, don't pte_mkwrite for CoW. */ + writable = is_continue && !(dst_vma->vm_flags & VM_SHARED) + ? 0 + : dst_vma->vm_flags & VM_WRITE; + if (writable) _dst_pte = pte_mkwrite(pte_mkdirty(_dst_pte)); else { /* @@ -2455,7 +2458,7 @@ int shmem_mcopy_atomic_pte(struct mm_struct *dst_mm, pmd_t *dst_pmd, ret = -EFAULT; max_off = DIV_ROUND_UP(i_size_read(inode), PAGE_SIZE); - if (unlikely(offset >= max_off)) + if (unlikely(pgoff >= max_off)) goto out_release_unlock; ret = -EEXIST; @@ -2485,13 +2488,14 @@ int shmem_mcopy_atomic_pte(struct mm_struct *dst_mm, pmd_t *dst_pmd, return ret; out_release_unlock: pte_unmap_unlock(dst_pte, ptl); - ClearPageDirty(page); - delete_from_page_cache(page); + if (!is_continue) + delete_from_page_cache(page); out_release: unlock_page(page); put_page(page); out_unacct_blocks: - shmem_inode_unacct_blocks(inode, 1); + if (!is_continue) + shmem_inode_unacct_blocks(inode, 1); goto out; } #endif /* CONFIG_USERFAULTFD */ diff --git a/tools/testing/selftests/vm/userfaultfd.c b/tools/testing/selftests/vm/userfaultfd.c index f6c86b036d0f..d8541a59dae5 100644 --- a/tools/testing/selftests/vm/userfaultfd.c +++ b/tools/testing/selftests/vm/userfaultfd.c @@ -485,6 +485,7 @@ static void wp_range(int ufd, __u64 start, __u64 len, bool wp) static void continue_range(int ufd, __u64 start, __u64 len) { struct uffdio_continue req; + int ret; req.range.start = start; req.range.len = len; @@ -493,6 +494,17 @@ static void continue_range(int ufd, __u64 start, __u64 len) if (ioctl(ufd, UFFDIO_CONTINUE, &req)) err("UFFDIO_CONTINUE failed for address 0x%" PRIx64, (uint64_t)start); + + /* + * Error handling within the kernel for continue is subtly different + * from copy or zeropage, so it may be a source of bugs. Trigger an + * error (-EEXIST) on purpose, to verify doing so doesn't cause a BUG. + */ + req.mapped = 0; + ret = ioctl(ufd, UFFDIO_CONTINUE, &req); + if (ret >= 0 || req.mapped != -EEXIST) + err("failed to exercise UFFDIO_CONTINUE error handling, ret=%d, mapped=%" PRId64, + ret, req.mapped); } static void *locking_thread(void *arg) -- 2.31.0.291.g576ba9dcdaf-goog

4 years, 3 months

2
3
0 0

Bidding invitation

by Albert Bourla

Good Day Sir/Ms, We are please to invite you or your company to quote the following item listed below: Product/Model No: A702TH FYNE PRESSURE REGULATOR Model Number: A702TH Qty. 30 units Compulsory,Kindly send your quotation to: quotation(a)pfizerbvsupply.com for immediate approval. Kind Regards, Albert Bourla PFIZER B.V Supply Chain Manager Tel: +31(0)208080 880 ADDRESS: Rivium Westlaan 142, 2909 LD Capelle aan den IJssel, Netherlands

4 years, 3 months

1
0
0 0

[PATCH] kvm: fix minor typos in x86/kvm.h and selftests/processor.c

by Emanuele Giuseppe Esposito

Signed-off-by: Emanuele Giuseppe Esposito <eesposit(a)redhat.com> --- tools/arch/x86/include/uapi/asm/kvm.h | 2 +- tools/testing/selftests/kvm/lib/x86_64/processor.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/tools/arch/x86/include/uapi/asm/kvm.h b/tools/arch/x86/include/uapi/asm/kvm.h index 5a3022c8af82..e00d44bc5f55 100644 --- a/tools/arch/x86/include/uapi/asm/kvm.h +++ b/tools/arch/x86/include/uapi/asm/kvm.h @@ -190,7 +190,7 @@ struct kvm_msrs { /* for KVM_GET_MSR_INDEX_LIST */ struct kvm_msr_list { - __u32 nmsrs; /* number of msrs in entries */ + __u32 nmsrs; /* number of msrs in indices */ __u32 indices[0]; }; diff --git a/tools/testing/selftests/kvm/lib/x86_64/processor.c b/tools/testing/selftests/kvm/lib/x86_64/processor.c index a8906e60a108..e676fe40bfe6 100644 --- a/tools/testing/selftests/kvm/lib/x86_64/processor.c +++ b/tools/testing/selftests/kvm/lib/x86_64/processor.c @@ -714,7 +714,7 @@ uint64_t kvm_get_feature_msr(uint64_t msr_index) * * Return: KVM CPUID (KVM_GET_CPUID2) * - * Set the VCPU's CPUID. + * Get the VCPU's CPUID. */ struct kvm_cpuid2 *vcpu_get_cpuid(struct kvm_vm *vm, uint32_t vcpuid) { -- 2.30.2

4 years, 3 months

1
0
0 0

[PATCH V4 00/10] PKS Add Protection Key Supervisor support

by ira.weiny＠intel.com

From: Ira Weiny <ira.weiny(a)intel.com> Introduce a new page protection mechanism for supervisor pages, Protection Key Supervisor (PKS). Generally PKS enables protections on 'domains' of supervisor pages to limit supervisor mode access to pages beyond the normal paging protections. PKS works in a similar fashion to user space pkeys, PKU. As with PKU, supervisor pkeys are checked in addition to normal paging protections and Access or Writes can be disabled via a MSR update without TLB flushes when permissions change. Also like PKU, a page mapping is assigned to a domain by setting pkey bits in the page table entry for that mapping. Access is controlled through a PKRS register which is updated via WRMSR/RDMSR. XSAVE is not supported for the PKRS MSR. Therefore the implementation saves/restores the MSR across context switches and during exceptions. Nested exceptions are supported by each exception getting a new PKS state. For consistent behavior with current paging protections, pkey 0 is reserved and configured to allow full access via the pkey mechanism, thus preserving the default paging protections on mappings with the default pkey value of 0. Other keys, (1-15) are allocated by an allocator which prepares us for key contention from day one. Kernel users should be prepared for the allocator to fail either because of key exhaustion or due to PKS not being supported on the CPU instance. The following are key attributes of PKS. 1) Fast switching of permissions 1a) Prevents access without page table manipulations 1b) No TLB flushes required 2) Works on a per thread basis PKS is available with 4 and 5 level paging. Like PKRU it consumes 4 bits from the PTE to store the pkey within the entry. All code to support PKS is configured via ARCH_ENABLE_SUPERVISOR_PKEYS which is designed to only be turned on when a user is configured on in the kernel. Those users must depend on ARCH_HAS_SUPERVISOR_PKEYS to properly work with other architectures which do not yet support PKS. Originally this series was submitted as part of a large patch set which converted the kmap call sites.[1] Many follow on discussions revealed a few problems. The first of which was that some callers leak a kmap mapping across threads rather than containing it to a critical section. Attempts were made to see if these 'global kmaps' could be supported.[2] However, supporting global kmaps had many problems. Work is being done in parallel on converting as many kmap calls to the new kmap_local_page().[3] Changes from V3 [4] Add ARCH_ENABLE_SUPERVISOR_PKEYS config which is selected by kernel users to add the functionality to the core. However, they should only select this if ARCH_HAS_SUPERVISOR_PKEYS is available. Clean up test code for context switching Adjust for extended_pt_regs Reduce output unless --debug is specified Address internal review comments from Dan Williams and Dave Hansen Help with macros and assembly coding Change names of various functions Clean up documentation Move all #ifdefery into header files. Clean up cover letter. Make extended_pt_regs handling a macro rather than coding around every call to C Add macross for PKS shift/mask New patch : x86/pks: Add additional PKEY helper macros Preserve pkrs_cache as static when PKS_TEST is not configured Remove unnecessary pr_* prints Clarify pks_key_alloc flags parameter Change CONFIG_PKS_TESTING to CONFIG_PKS_TEST Clean up test code separation from main code in fault.c Remove module boilerplate from test code Clean up all commit messages Address comments from Thomas Gleixner Provide a warning and fallback to no protection if a global mapping is requested. Fix context switch. Fix where pks_sched_in() is called. Fix test to actually do a context switch Remove unecessary noinstr's From Andy Lutomirski Use extended_pt_regs idea to stash pks values on the stack Drop patches 5/10 and 7/10 And use extended_pt_regs to print pkey info on fault Adjust tests Comments from Randy Dunlap: Fix gramatical errors in doc Clean up kernel docs Rebase to 5.12 [1] https://lore.kernel.org/lkml/20201009195033.3208459-1-ira.weiny@intel.com/ [2] https://lore.kernel.org/lkml/87mtycqcjf.fsf@nanos.tec.linutronix.de/ [3] https://lore.kernel.org/lkml/20210128061503.1496847-1-ira.weiny@intel.com/ https://lore.kernel.org/lkml/20210210062221.3023586-1-ira.weiny@intel.com/ https://lore.kernel.org/lkml/20210205170030.856723-1-ira.weiny@intel.com/ https://lore.kernel.org/lkml/20210217024826.3466046-1-ira.weiny@intel.com/ [4] https://lore.kernel.org/lkml/20201106232908.364581-1-ira.weiny@intel.com/ </proposed cover letter> Fenghua Yu (1): x86/pks: Add PKS kernel API Ira Weiny (9): x86/pkeys: Create pkeys_common.h x86/fpu: Refactor arch_set_user_pkey_access() for PKS support x86/pks: Add additional PKEY helper macros x86/pks: Add PKS defines and Kconfig options x86/pks: Add PKS setup code x86/fault: Adjust WARN_ON for PKey fault x86/pks: Preserve the PKRS MSR on context switch x86/entry: Preserve PKRS MSR across exceptions x86/pks: Add PKS test code Documentation/core-api/protection-keys.rst | 111 +++- arch/x86/Kconfig | 1 + arch/x86/entry/calling.h | 26 + arch/x86/entry/common.c | 58 ++ arch/x86/entry/entry_64.S | 22 +- arch/x86/entry/entry_64_compat.S | 6 +- arch/x86/include/asm/cpufeatures.h | 1 + arch/x86/include/asm/disabled-features.h | 8 +- arch/x86/include/asm/msr-index.h | 1 + arch/x86/include/asm/pgtable.h | 10 +- arch/x86/include/asm/pgtable_types.h | 12 + arch/x86/include/asm/pkeys.h | 4 + arch/x86/include/asm/pkeys_common.h | 34 + arch/x86/include/asm/pks.h | 54 ++ arch/x86/include/asm/processor-flags.h | 2 + arch/x86/include/asm/processor.h | 43 +- arch/x86/include/uapi/asm/processor-flags.h | 2 + arch/x86/kernel/cpu/common.c | 2 + arch/x86/kernel/fpu/xstate.c | 22 +- arch/x86/kernel/head_64.S | 7 +- arch/x86/kernel/process.c | 3 + arch/x86/kernel/process_64.c | 2 + arch/x86/mm/fault.c | 27 +- arch/x86/mm/pkeys.c | 218 +++++- include/linux/pgtable.h | 4 + include/linux/pkeys.h | 34 + kernel/entry/common.c | 14 +- lib/Kconfig.debug | 11 + lib/Makefile | 3 + lib/pks/Makefile | 3 + lib/pks/pks_test.c | 693 ++++++++++++++++++++ mm/Kconfig | 5 + tools/testing/selftests/x86/Makefile | 3 +- tools/testing/selftests/x86/test_pks.c | 150 +++++ 34 files changed, 1519 insertions(+), 77 deletions(-) create mode 100644 arch/x86/include/asm/pkeys_common.h create mode 100644 arch/x86/include/asm/pks.h create mode 100644 lib/pks/Makefile create mode 100644 lib/pks/pks_test.c create mode 100644 tools/testing/selftests/x86/test_pks.c -- 2.28.0.rc0.12.gb6a658bd00c9

4 years, 3 months

3
15
0 0

BUG: key ffff000800eba398 has not been registered!

by Naresh Kamboju

While running kselftest recently added gpio gpio-sim.sh test case the following warning was triggered on Linux next tag 20210330 tag running on arm64 juno and hikey devices. GOOD: next-20210326 BAD: next-20210330 # selftests: gpio: gpio-sim.sh # 1. chip_name and dev_name attributes # 1.1. Chip name is communicated to user [ 143.081193] BUG: key ffff000800eba398 has not been registered! [ 143.087326] ------------[ cut here ]------------ [ 143.091987] DEBUG_LOCKS_WARN_ON(1) [ 143.092005] WARNING: CPU: 1 PID: 1821 at /usr/src/kernel/kernel/locking/lockdep.c:4688 lockdep_init_map_type+0xf0/0x298 [ 143.106223] Modules linked in: gpio_sim rfkill tda998x cec drm_kms_helper drm crct10dif_ce fuse [last unloaded: gpio_mockup] [ 143.117495] CPU: 1 PID: 1821 Comm: mv Not tainted 5.12.0-rc5-next-20210330 #1 [ 143.124645] Hardware name: ARM Juno development board (r2) (DT) [ 143.130572] pstate: 40000005 (nZcv daif -PAN -UAO -TCO BTYPE=--) [ 143.136589] pc : lockdep_init_map_type+0xf0/0x298 [ 143.141302] lr : lockdep_init_map_type+0xf0/0x298 [ 143.146014] sp : ffff800013fb3560 [ 143.149330] x29: ffff800013fb3560 x28: 00000000ffffee4b [ 143.154655] x27: 00000000000011b4 x26: 0000000000001000 [ 143.159979] x25: ffff000800eba380 x24: 0000000000000000 [ 143.165303] x23: 0000000000000000 x22: 0000000000000000 [ 143.170626] x21: ffff80001382b000 x20: ffff000800eba398 [ 143.175949] x19: ffff000827ac32a8 x18: ffffffffffffffff [ 143.181273] x17: 0000000000000000 x16: 0000000000000000 [ 143.186595] x15: ffff800012900a88 x14: ffff800093fb3167 [ 143.191918] x13: ffff800013fb3175 x12: 000000000000a0ec [ 143.197241] x11: 0000000005f5e0ff x10: ffff800013fb30c0 [ 143.202565] x9 : ffff800013fb3560 x8 : 4e5241575f534b43 [ 143.207888] x7 : ffff800012989ad8 x6 : ffff800013fb3180 [ 143.213211] x5 : 0000000000000001 x4 : 0000000000000001 [ 143.218534] x3 : ffff800012901000 x2 : 0000000000000000 [ 143.223856] x1 : b4b7acac5f71bc00 x0 : 0000000000000000 [ 143.229180] Call trace: [ 143.231625] lockdep_init_map_type+0xf0/0x298 [ 143.235989] __kernfs_create_file+0xa8/0x1d0 [ 143.240268] sysfs_add_file_mode_ns+0xa8/0x1f8 [ 143.244718] internal_create_group+0x118/0x420 [ 143.249169] sysfs_create_group+0x2c/0x38 [ 143.253185] gpio_sim_probe+0x358/0x3c0 [gpio_sim] [ 143.257995] platform_probe+0x6c/0xd8 [ 143.261663] really_probe+0x16c/0x508 [ 143.265332] driver_probe_device+0x104/0x178 [ 143.269610] __device_attach_driver+0xa4/0x130 [ 143.274062] bus_for_each_drv+0x78/0xd8 [ 143.277903] __device_attach+0xf0/0x178 [ 143.281745] device_initial_probe+0x24/0x30 [ 143.285935] bus_probe_device+0xa0/0xa8 [ 143.289776] device_add+0x424/0x810 [ 143.293270] platform_device_add+0x12c/0x2c0 [ 143.297545] platform_device_register_full+0x124/0x150 [ 143.302692] gpio_sim_config_commit_item+0x160/0x1e0 [gpio_sim] [ 143.308628] configfs_rename+0x1dc/0x220 [ 143.312557] vfs_rename+0x394/0x960 [ 143.316051] do_renameat2+0x408/0x4c0 [ 143.319718] __arm64_sys_renameat+0x5c/0x70 [ 143.323908] el0_svc_common+0x7c/0x158 [ 143.327665] do_el0_svc+0x38/0x90 [ 143.330985] el0_svc+0x20/0x30 [ 143.334045] el0_sync_handler+0x8c/0xb0 [ 143.337886] el0_sync+0x13c/0x140 [ 143.341204] irq event stamp: 5607 [ 143.344520] hardirqs last enabled at (5607): [<ffff800011462dd8>] _raw_spin_unlock_irq+0x48/0x90 [ 143.353410] hardirqs last disabled at (5606): [<ffff8000114586c4>] __schedule+0x364/0x950 [ 143.361605] softirqs last enabled at (5602): [<ffff800010010958>] __do_softirq+0x510/0x63c [ 143.369971] softirqs last disabled at (5577): [<ffff8000100a7474>] irq_exit+0x1b4/0x1c0 [ 143.377992] ---[ end trace bc3c86ef609281aa ]--- # 1.2. chip_name returns 'none' if the chip is still pending Reported-by: Naresh Kamboju <naresh.kamboju(a)linaro.org> metadata: git branch: master git repo: https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git git describe: next-20210330 kernel-config: http://snapshots.linaro.org/openembedded/lkft/lkft/sumo/juno/lkft/linux-nex… Full test log link, https://qa-reports.linaro.org/lkft/linux-next-master/build/next-20210330/te… git log --oneline next-20210326..next-20210330 -- tools/testing/selftests/gpio/ 9d940ab72645 selftests: gpio: add test cases for gpio-sim 8a4cb2823240 selftests: gpio: add a helper for reading GPIO line names ab1dbed6f4e8 selftests: gpio: provide a helper for reading chip info -- Linaro LKFT https://lkft.linaro.org

4 years, 3 months

1
0
0 0

[PATCH v8 1/4] lib: vsprintf: scanf: Negative number must have field width > 1

by Richard Fitzgerald

If a signed number field starts with a '-' the field width must be > 1, or unlimited, to allow at least one digit after the '-'. This patch adds a check for this. If a signed field starts with '-' and field_width == 1 the scanf will quit. It is ok for a signed number field to have a field width of 1 if it starts with a digit. In that case the single digit can be converted. Signed-off-by: Richard Fitzgerald <rf(a)opensource.cirrus.com> Reviewed-by: Petr Mladek <pmladek(a)suse.com> Acked-by: Andy Shevchenko <andriy.shevchenko(a)linux.intel.com> --- lib/vsprintf.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/lib/vsprintf.c b/lib/vsprintf.c index 41ddc353ebb8..f78651e9b030 100644 --- a/lib/vsprintf.c +++ b/lib/vsprintf.c @@ -3466,8 +3466,12 @@ int vsscanf(const char *buf, const char *fmt, va_list args) str = skip_spaces(str); digit = *str; - if (is_sign && digit == '-') + if (is_sign && digit == '-') { + if (field_width == 1) + break; + digit = *(str + 1); + } if (!digit || (base == 16 && !isxdigit(digit)) -- 2.20.1

4 years, 3 months

1
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[PATCH v2] userfaultfd/shmem: fix MCOPY_ATOMIC_CONTNUE behavior

by Axel Rasmussen

Previously, we shared too much of the code with COPY and ZEROPAGE, so we manipulated things in various invalid ways: - Previously, we unconditionally called shmem_inode_acct_block. In the continue case, we're looking up an existing page which would have been accounted for properly when it was allocated. So doing it twice results in double-counting, and eventually leaking. - Previously, we made the pte writable whenever the VMA was writable. However, for continue, consider this case: 1. A tmpfs file was created 2. The non-UFFD-registered side mmap()-s with MAP_SHARED 3. The UFFD-registered side mmap()-s with MAP_PRIVATE In this case, even though the UFFD-registered VMA may be writable, we still want CoW behavior. So, check for this case and don't make the pte writable. - The offset / max_off checking doesn't necessarily hurt anything, but it's not needed in the CONTINUE case, so skip it. - Previously, we unconditionally called ClearPageDirty() in the error path. In the continue case though, since this is an existing page, it might have already been dirty before we started touching it. So, remember whether or not it was dirty before we set_page_dirty(), and only clear the bit if it wasn't dirty before. - Previously, we unconditionally removed the page from the page cache in the error path. But in the continue case, we didn't add it - it was already there because the page is present in some second (non-UFFD-registered) mapping. So, removing it is invalid. Because the error handling issues are easy to exercise in the selftest, make a small modification there to do so. Finally, refactor shmem_mcopy_atomic_pte a bit. By this point, we've added a lot of "if (!is_continue)"-s everywhere. It's cleaner to just check for that mode first thing, and then "goto" down to where the parts we actually want are. This leaves the code in between cleaner. Changes since v1: - Refactor to skip ahead with goto, instead of adding several more "if (!is_continue)". - Fix unconditional ClearPageDirty(). - Don't pte_mkwrite() when is_continue && !VM_SHARED. Fixes: 00da60b9d0a0 ("userfaultfd: support minor fault handling for shmem") Signed-off-by: Axel Rasmussen <axelrasmussen(a)google.com> --- mm/shmem.c | 67 ++++++++++++++---------- tools/testing/selftests/vm/userfaultfd.c | 12 +++++ 2 files changed, 51 insertions(+), 28 deletions(-) diff --git a/mm/shmem.c b/mm/shmem.c index d2e0e81b7d2e..8ab1f1f29987 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -2378,17 +2378,22 @@ int shmem_mcopy_atomic_pte(struct mm_struct *dst_mm, pmd_t *dst_pmd, pte_t _dst_pte, *dst_pte; int ret; pgoff_t offset, max_off; - - ret = -ENOMEM; - if (!shmem_inode_acct_block(inode, 1)) - goto out; + int writable; + bool was_dirty; if (is_continue) { ret = -EFAULT; page = find_lock_page(mapping, pgoff); if (!page) - goto out_unacct_blocks; - } else if (!*pagep) { + goto out; + goto install_ptes; + } + + ret = -ENOMEM; + if (!shmem_inode_acct_block(inode, 1)) + goto out; + + if (!*pagep) { page = shmem_alloc_page(gfp, info, pgoff); if (!page) goto out_unacct_blocks; @@ -2415,13 +2420,11 @@ int shmem_mcopy_atomic_pte(struct mm_struct *dst_mm, pmd_t *dst_pmd, *pagep = NULL; } - if (!is_continue) { - VM_BUG_ON(PageSwapBacked(page)); - VM_BUG_ON(PageLocked(page)); - __SetPageLocked(page); - __SetPageSwapBacked(page); - __SetPageUptodate(page); - } + VM_BUG_ON(PageSwapBacked(page)); + VM_BUG_ON(PageLocked(page)); + __SetPageLocked(page); + __SetPageSwapBacked(page); + __SetPageUptodate(page); ret = -EFAULT; offset = linear_page_index(dst_vma, dst_addr); @@ -2429,16 +2432,18 @@ int shmem_mcopy_atomic_pte(struct mm_struct *dst_mm, pmd_t *dst_pmd, if (unlikely(offset >= max_off)) goto out_release; - /* If page wasn't already in the page cache, add it. */ - if (!is_continue) { - ret = shmem_add_to_page_cache(page, mapping, pgoff, NULL, - gfp & GFP_RECLAIM_MASK, dst_mm); - if (ret) - goto out_release; - } + ret = shmem_add_to_page_cache(page, mapping, pgoff, NULL, + gfp & GFP_RECLAIM_MASK, dst_mm); + if (ret) + goto out_release; +install_ptes: _dst_pte = mk_pte(page, dst_vma->vm_page_prot); - if (dst_vma->vm_flags & VM_WRITE) + /* For CONTINUE on a non-shared VMA, don't pte_mkwrite for CoW. */ + writable = is_continue && !(dst_vma->vm_flags & VM_SHARED) + ? 0 + : dst_vma->vm_flags & VM_WRITE; + if (writable) _dst_pte = pte_mkwrite(pte_mkdirty(_dst_pte)); else { /* @@ -2448,15 +2453,18 @@ int shmem_mcopy_atomic_pte(struct mm_struct *dst_mm, pmd_t *dst_pmd, * unconditionally before unlock_page(), but doing it * only if VM_WRITE is not set is faster. */ + was_dirty = PageDirty(page); set_page_dirty(page); } dst_pte = pte_offset_map_lock(dst_mm, dst_pmd, dst_addr, &ptl); - ret = -EFAULT; - max_off = DIV_ROUND_UP(i_size_read(inode), PAGE_SIZE); - if (unlikely(offset >= max_off)) - goto out_release_unlock; + if (!is_continue) { + ret = -EFAULT; + max_off = DIV_ROUND_UP(i_size_read(inode), PAGE_SIZE); + if (unlikely(offset >= max_off)) + goto out_release_unlock; + } ret = -EEXIST; if (!pte_none(*dst_pte)) @@ -2485,13 +2493,16 @@ int shmem_mcopy_atomic_pte(struct mm_struct *dst_mm, pmd_t *dst_pmd, return ret; out_release_unlock: pte_unmap_unlock(dst_pte, ptl); - ClearPageDirty(page); - delete_from_page_cache(page); + if (!was_dirty) + ClearPageDirty(page); + if (!is_continue) + delete_from_page_cache(page); out_release: unlock_page(page); put_page(page); out_unacct_blocks: - shmem_inode_unacct_blocks(inode, 1); + if (!is_continue) + shmem_inode_unacct_blocks(inode, 1); goto out; } #endif /* CONFIG_USERFAULTFD */ diff --git a/tools/testing/selftests/vm/userfaultfd.c b/tools/testing/selftests/vm/userfaultfd.c index f6c86b036d0f..d8541a59dae5 100644 --- a/tools/testing/selftests/vm/userfaultfd.c +++ b/tools/testing/selftests/vm/userfaultfd.c @@ -485,6 +485,7 @@ static void wp_range(int ufd, __u64 start, __u64 len, bool wp) static void continue_range(int ufd, __u64 start, __u64 len) { struct uffdio_continue req; + int ret; req.range.start = start; req.range.len = len; @@ -493,6 +494,17 @@ static void continue_range(int ufd, __u64 start, __u64 len) if (ioctl(ufd, UFFDIO_CONTINUE, &req)) err("UFFDIO_CONTINUE failed for address 0x%" PRIx64, (uint64_t)start); + + /* + * Error handling within the kernel for continue is subtly different + * from copy or zeropage, so it may be a source of bugs. Trigger an + * error (-EEXIST) on purpose, to verify doing so doesn't cause a BUG. + */ + req.mapped = 0; + ret = ioctl(ufd, UFFDIO_CONTINUE, &req); + if (ret >= 0 || req.mapped != -EEXIST) + err("failed to exercise UFFDIO_CONTINUE error handling, ret=%d, mapped=%" PRId64, + ret, req.mapped); } static void *locking_thread(void *arg) -- 2.31.0.291.g576ba9dcdaf-goog

4 years, 3 months

2
1
0 0

[PATCH AUTOSEL 5.10 27/33] selftests/vm: fix out-of-tree build

by Sasha Levin

From: Rong Chen <rong.a.chen(a)intel.com> [ Upstream commit 19ec368cbc7ee1915e78c120b7a49c7f14734192 ] When building out-of-tree, attempting to make target from $(OUTPUT) directory: make[1]: *** No rule to make target '$(OUTPUT)/protection_keys.c', needed by '$(OUTPUT)/protection_keys_32'. Link: https://lkml.kernel.org/r/20210315094700.522753-1-rong.a.chen@intel.com Signed-off-by: Rong Chen <rong.a.chen(a)intel.com> Reported-by: kernel test robot <lkp(a)intel.com> Cc: Shuah Khan <shuah(a)kernel.org> Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds(a)linux-foundation.org> Signed-off-by: Sasha Levin <sashal(a)kernel.org> --- tools/testing/selftests/vm/Makefile | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/tools/testing/selftests/vm/Makefile b/tools/testing/selftests/vm/Makefile index e63f31632708..2cf32e6b376e 100644 --- a/tools/testing/selftests/vm/Makefile +++ b/tools/testing/selftests/vm/Makefile @@ -99,7 +99,7 @@ endef ifeq ($(CAN_BUILD_I386),1) $(BINARIES_32): CFLAGS += -m32 $(BINARIES_32): LDLIBS += -lrt -ldl -lm -$(BINARIES_32): %_32: %.c +$(BINARIES_32): $(OUTPUT)/%_32: %.c $(CC) $(CFLAGS) $(EXTRA_CFLAGS) $(notdir $^) $(LDLIBS) -o $@ $(foreach t,$(TARGETS),$(eval $(call gen-target-rule-32,$(t)))) endif @@ -107,7 +107,7 @@ endif ifeq ($(CAN_BUILD_X86_64),1) $(BINARIES_64): CFLAGS += -m64 $(BINARIES_64): LDLIBS += -lrt -ldl -$(BINARIES_64): %_64: %.c +$(BINARIES_64): $(OUTPUT)/%_64: %.c $(CC) $(CFLAGS) $(EXTRA_CFLAGS) $(notdir $^) $(LDLIBS) -o $@ $(foreach t,$(TARGETS),$(eval $(call gen-target-rule-64,$(t)))) endif -- 2.30.1

4 years, 3 months

1
0
0 0

[PATCH AUTOSEL 5.10 20/33] kselftest/arm64: sve: Do not use non-canonical FFR register value

by Sasha Levin

From: Andre Przywara <andre.przywara(a)arm.com> [ Upstream commit 7011d72588d16a9e5f5d85acbc8b10019809599c ] The "First Fault Register" (FFR) is an SVE register that mimics a predicate register, but clears bits when a load or store fails to handle an element of a vector. The supposed usage scenario is to initialise this register (using SETFFR), then *read* it later on to learn about elements that failed to load or store. Explicit writes to this register using the WRFFR instruction are only supposed to *restore* values previously read from the register (for context-switching only). As the manual describes, this register holds only certain values, it: "... contains a monotonic predicate value, in which starting from bit 0 there are zero or more 1 bits, followed only by 0 bits in any remaining bit positions." Any other value is UNPREDICTABLE and is not supposed to be "restored" into the register. The SVE test currently tries to write a signature pattern into the register, which is *not* a canonical FFR value. Apparently the existing setups treat UNPREDICTABLE as "read-as-written", but a new implementation actually only stores canonical values. As a consequence, the sve-test fails immediately when comparing the FFR value: ----------- # ./sve-test Vector length: 128 bits PID: 207 Mismatch: PID=207, iteration=0, reg=48 Expected [cf00] Got [0f00] Aborted ----------- Fix this by only populating the FFR with proper canonical values. Effectively the requirement described above limits us to 17 unique values over 16 bits worth of FFR, so we condense our signature down to 4 bits (2 bits from the PID, 2 bits from the generation) and generate the canonical pattern from it. Any bits describing elements above the minimum 128 bit are set to 0. This aligns the FFR usage to the architecture and fixes the test on microarchitectures implementing FFR in a more restricted way. Signed-off-by: Andre Przywara <andre.przywara(a)arm.com> Reviwed-by: Mark Brown <broonie(a)kernel.org> Link: https://lore.kernel.org/r/20210319120128.29452-1-andre.przywara@arm.com Signed-off-by: Will Deacon <will(a)kernel.org> Signed-off-by: Sasha Levin <sashal(a)kernel.org> --- tools/testing/selftests/arm64/fp/sve-test.S | 22 ++++++++++++++++----- 1 file changed, 17 insertions(+), 5 deletions(-) diff --git a/tools/testing/selftests/arm64/fp/sve-test.S b/tools/testing/selftests/arm64/fp/sve-test.S index f95074c9b48b..07f14e279a90 100644 --- a/tools/testing/selftests/arm64/fp/sve-test.S +++ b/tools/testing/selftests/arm64/fp/sve-test.S @@ -284,16 +284,28 @@ endfunction // Set up test pattern in the FFR // x0: pid // x2: generation +// +// We need to generate a canonical FFR value, which consists of a number of +// low "1" bits, followed by a number of zeros. This gives us 17 unique values +// per 16 bits of FFR, so we create a 4 bit signature out of the PID and +// generation, and use that as the initial number of ones in the pattern. +// We fill the upper lanes of FFR with zeros. // Beware: corrupts P0. function setup_ffr mov x4, x30 - bl pattern + and w0, w0, #0x3 + bfi w0, w2, #2, #2 + mov w1, #1 + lsl w1, w1, w0 + sub w1, w1, #1 + ldr x0, =ffrref - ldr x1, =scratch - rdvl x2, #1 - lsr x2, x2, #3 - bl memcpy + strh w1, [x0], 2 + rdvl x1, #1 + lsr x1, x1, #3 + sub x1, x1, #2 + bl memclr mov x0, #0 ldr x1, =ffrref -- 2.30.1

4 years, 3 months

1
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[PATCH AUTOSEL 5.10 07/33] kunit: tool: Fix a python tuple typing error

by Sasha Levin

From: David Gow <davidgow(a)google.com> [ Upstream commit 7421b1a4d10c633ca5f14c8236d3e2c1de07e52b ] The first argument to namedtuple() should match the name of the type, which wasn't the case for KconfigEntryBase. Fixing this is enough to make mypy show no python typing errors again. Fixes 97752c39bd ("kunit: kunit_tool: Allow .kunitconfig to disable config items") Signed-off-by: David Gow <davidgow(a)google.com> Reviewed-by: Daniel Latypov <dlatypov(a)google.com> Acked-by: Brendan Higgins <brendanhiggins(a)google.com> Signed-off-by: Shuah Khan <skhan(a)linuxfoundation.org> Signed-off-by: Sasha Levin <sashal(a)kernel.org> --- tools/testing/kunit/kunit_config.py | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/tools/testing/kunit/kunit_config.py b/tools/testing/kunit/kunit_config.py index 02ffc3a3e5dc..b30e9d6db6b4 100644 --- a/tools/testing/kunit/kunit_config.py +++ b/tools/testing/kunit/kunit_config.py @@ -12,7 +12,7 @@ import re CONFIG_IS_NOT_SET_PATTERN = r'^# CONFIG_(\w+) is not set$' CONFIG_PATTERN = r'^CONFIG_(\w+)=(\S+|".*")$' -KconfigEntryBase = collections.namedtuple('KconfigEntry', ['name', 'value']) +KconfigEntryBase = collections.namedtuple('KconfigEntryBase', ['name', 'value']) class KconfigEntry(KconfigEntryBase): -- 2.30.1

4 years, 3 months

1
0
0 0

[PATCH AUTOSEL 5.11 32/38] selftests/vm: fix out-of-tree build

by Sasha Levin

From: Rong Chen <rong.a.chen(a)intel.com> [ Upstream commit 19ec368cbc7ee1915e78c120b7a49c7f14734192 ] When building out-of-tree, attempting to make target from $(OUTPUT) directory: make[1]: *** No rule to make target '$(OUTPUT)/protection_keys.c', needed by '$(OUTPUT)/protection_keys_32'. Link: https://lkml.kernel.org/r/20210315094700.522753-1-rong.a.chen@intel.com Signed-off-by: Rong Chen <rong.a.chen(a)intel.com> Reported-by: kernel test robot <lkp(a)intel.com> Cc: Shuah Khan <shuah(a)kernel.org> Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds(a)linux-foundation.org> Signed-off-by: Sasha Levin <sashal(a)kernel.org> --- tools/testing/selftests/vm/Makefile | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/tools/testing/selftests/vm/Makefile b/tools/testing/selftests/vm/Makefile index d42115e4284d..8b0cd421ebd3 100644 --- a/tools/testing/selftests/vm/Makefile +++ b/tools/testing/selftests/vm/Makefile @@ -101,7 +101,7 @@ endef ifeq ($(CAN_BUILD_I386),1) $(BINARIES_32): CFLAGS += -m32 $(BINARIES_32): LDLIBS += -lrt -ldl -lm -$(BINARIES_32): %_32: %.c +$(BINARIES_32): $(OUTPUT)/%_32: %.c $(CC) $(CFLAGS) $(EXTRA_CFLAGS) $(notdir $^) $(LDLIBS) -o $@ $(foreach t,$(TARGETS),$(eval $(call gen-target-rule-32,$(t)))) endif @@ -109,7 +109,7 @@ endif ifeq ($(CAN_BUILD_X86_64),1) $(BINARIES_64): CFLAGS += -m64 $(BINARIES_64): LDLIBS += -lrt -ldl -$(BINARIES_64): %_64: %.c +$(BINARIES_64): $(OUTPUT)/%_64: %.c $(CC) $(CFLAGS) $(EXTRA_CFLAGS) $(notdir $^) $(LDLIBS) -o $@ $(foreach t,$(TARGETS),$(eval $(call gen-target-rule-64,$(t)))) endif -- 2.30.1

4 years, 3 months

1
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[PATCH AUTOSEL 5.11 23/38] kselftest/arm64: sve: Do not use non-canonical FFR register value

by Sasha Levin

From: Andre Przywara <andre.przywara(a)arm.com> [ Upstream commit 7011d72588d16a9e5f5d85acbc8b10019809599c ] The "First Fault Register" (FFR) is an SVE register that mimics a predicate register, but clears bits when a load or store fails to handle an element of a vector. The supposed usage scenario is to initialise this register (using SETFFR), then *read* it later on to learn about elements that failed to load or store. Explicit writes to this register using the WRFFR instruction are only supposed to *restore* values previously read from the register (for context-switching only). As the manual describes, this register holds only certain values, it: "... contains a monotonic predicate value, in which starting from bit 0 there are zero or more 1 bits, followed only by 0 bits in any remaining bit positions." Any other value is UNPREDICTABLE and is not supposed to be "restored" into the register. The SVE test currently tries to write a signature pattern into the register, which is *not* a canonical FFR value. Apparently the existing setups treat UNPREDICTABLE as "read-as-written", but a new implementation actually only stores canonical values. As a consequence, the sve-test fails immediately when comparing the FFR value: ----------- # ./sve-test Vector length: 128 bits PID: 207 Mismatch: PID=207, iteration=0, reg=48 Expected [cf00] Got [0f00] Aborted ----------- Fix this by only populating the FFR with proper canonical values. Effectively the requirement described above limits us to 17 unique values over 16 bits worth of FFR, so we condense our signature down to 4 bits (2 bits from the PID, 2 bits from the generation) and generate the canonical pattern from it. Any bits describing elements above the minimum 128 bit are set to 0. This aligns the FFR usage to the architecture and fixes the test on microarchitectures implementing FFR in a more restricted way. Signed-off-by: Andre Przywara <andre.przywara(a)arm.com> Reviwed-by: Mark Brown <broonie(a)kernel.org> Link: https://lore.kernel.org/r/20210319120128.29452-1-andre.przywara@arm.com Signed-off-by: Will Deacon <will(a)kernel.org> Signed-off-by: Sasha Levin <sashal(a)kernel.org> --- tools/testing/selftests/arm64/fp/sve-test.S | 22 ++++++++++++++++----- 1 file changed, 17 insertions(+), 5 deletions(-) diff --git a/tools/testing/selftests/arm64/fp/sve-test.S b/tools/testing/selftests/arm64/fp/sve-test.S index 9210691aa998..e3e08d9c7020 100644 --- a/tools/testing/selftests/arm64/fp/sve-test.S +++ b/tools/testing/selftests/arm64/fp/sve-test.S @@ -284,16 +284,28 @@ endfunction // Set up test pattern in the FFR // x0: pid // x2: generation +// +// We need to generate a canonical FFR value, which consists of a number of +// low "1" bits, followed by a number of zeros. This gives us 17 unique values +// per 16 bits of FFR, so we create a 4 bit signature out of the PID and +// generation, and use that as the initial number of ones in the pattern. +// We fill the upper lanes of FFR with zeros. // Beware: corrupts P0. function setup_ffr mov x4, x30 - bl pattern + and w0, w0, #0x3 + bfi w0, w2, #2, #2 + mov w1, #1 + lsl w1, w1, w0 + sub w1, w1, #1 + ldr x0, =ffrref - ldr x1, =scratch - rdvl x2, #1 - lsr x2, x2, #3 - bl memcpy + strh w1, [x0], 2 + rdvl x1, #1 + lsr x1, x1, #3 + sub x1, x1, #2 + bl memclr mov x0, #0 ldr x1, =ffrref -- 2.30.1

4 years, 3 months

1
0
0 0

[PATCH AUTOSEL 5.11 08/38] kunit: tool: Fix a python tuple typing error

by Sasha Levin

From: David Gow <davidgow(a)google.com> [ Upstream commit 7421b1a4d10c633ca5f14c8236d3e2c1de07e52b ] The first argument to namedtuple() should match the name of the type, which wasn't the case for KconfigEntryBase. Fixing this is enough to make mypy show no python typing errors again. Fixes 97752c39bd ("kunit: kunit_tool: Allow .kunitconfig to disable config items") Signed-off-by: David Gow <davidgow(a)google.com> Reviewed-by: Daniel Latypov <dlatypov(a)google.com> Acked-by: Brendan Higgins <brendanhiggins(a)google.com> Signed-off-by: Shuah Khan <skhan(a)linuxfoundation.org> Signed-off-by: Sasha Levin <sashal(a)kernel.org> --- tools/testing/kunit/kunit_config.py | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/tools/testing/kunit/kunit_config.py b/tools/testing/kunit/kunit_config.py index bdd60230764b..27fe086d2d0d 100644 --- a/tools/testing/kunit/kunit_config.py +++ b/tools/testing/kunit/kunit_config.py @@ -13,7 +13,7 @@ from typing import List, Set CONFIG_IS_NOT_SET_PATTERN = r'^# CONFIG_(\w+) is not set$' CONFIG_PATTERN = r'^CONFIG_(\w+)=(\S+|".*")$' -KconfigEntryBase = collections.namedtuple('KconfigEntry', ['name', 'value']) +KconfigEntryBase = collections.namedtuple('KconfigEntryBase', ['name', 'value']) class KconfigEntry(KconfigEntryBase): -- 2.30.1

4 years, 3 months

1
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[PATCH v7 1/4] lib: vsprintf: scanf: Negative number must have field width > 1

by Richard Fitzgerald

If a signed number field starts with a '-' the field width must be > 1, or unlimited, to allow at least one digit after the '-'. This patch adds a check for this. If a signed field starts with '-' and field_width == 1 the scanf will quit. It is ok for a signed number field to have a field width of 1 if it starts with a digit. In that case the single digit can be converted. Signed-off-by: Richard Fitzgerald <rf(a)opensource.cirrus.com> Reviewed-by: Petr Mladek <pmladek(a)suse.com> Acked-by: Andy Shevchenko <andriy.shevchenko(a)linux.intel.com> --- lib/vsprintf.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/lib/vsprintf.c b/lib/vsprintf.c index 41ddc353ebb8..f78651e9b030 100644 --- a/lib/vsprintf.c +++ b/lib/vsprintf.c @@ -3466,8 +3466,12 @@ int vsscanf(const char *buf, const char *fmt, va_list args) str = skip_spaces(str); digit = *str; - if (is_sign && digit == '-') + if (is_sign && digit == '-') { + if (field_width == 1) + break; + digit = *(str + 1); + } if (!digit || (base == 16 && !isxdigit(digit)) -- 2.20.1

4 years, 3 months

2
5
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[RFC PATCH v5 00/10] KVM: selftests: some improvement and a new test for kvm page table

by Yanan Wang

Hi, This v5 series can mainly include two parts. Based on kvm queue branch: https://git.kernel.org/pub/scm/virt/kvm/kvm.git/log/?h=queue In the first part, all the known hugetlb backing src types specified with different hugepage sizes are listed, so that we can specify use of hugetlb source of the exact granularity that we want, instead of the system default ones. And as all the known hugetlb page sizes are listed, it's appropriate for all architectures. Besides, a helper that can get granularity of different backing src types(anonumous/thp/hugetlb) is added, so that we can use the accurate backing src granularity for kinds of alignment or guest memory accessing of vcpus. In the second part, a new test is added: This test is added to serve as a performance tester and a bug reproducer for kvm page table code (GPA->HPA mappings), it gives guidance for the people trying to make some improvement for kvm. And the following explains what we can exactly do through this test. The function guest_code() can cover the conditions where a single vcpu or multiple vcpus access guest pages within the same memory region, in three VM stages(before dirty logging, during dirty logging, after dirty logging). Besides, the backing src memory type(ANONYMOUS/THP/HUGETLB) of the tested memory region can be specified by users, which means normal page mappings or block mappings can be chosen by users to be created in the test. If ANONYMOUS memory is specified, kvm will create normal page mappings for the tested memory region before dirty logging, and update attributes of the page mappings from RO to RW during dirty logging. If THP/HUGETLB memory is specified, kvm will create block mappings for the tested memory region before dirty logging, and split the blcok mappings into normal page mappings during dirty logging, and coalesce the page mappings back into block mappings after dirty logging is stopped. So in summary, as a performance tester, this test can present the performance of kvm creating/updating normal page mappings, or the performance of kvm creating/splitting/recovering block mappings, through execution time. When we need to coalesce the page mappings back to block mappings after dirty logging is stopped, we have to firstly invalidate *all* the TLB entries for the page mappings right before installation of the block entry, because a TLB conflict abort error could occur if we can't invalidate the TLB entries fully. We have hit this TLB conflict twice on aarch64 software implementation and fixed it. As this test can imulate process from dirty logging enabled to dirty logging stopped of a VM with block mappings, so it can also reproduce this TLB conflict abort due to inadequate TLB invalidation when coalescing tables. Links about the TLB conflict abort: https://lore.kernel.org/lkml/20201201201034.116760-3-wangyanan55@huawei.com/ --- Change logs: v4->v5: - Use synchronization(sem_wait) for time measurement - Add a new patch about TEST_ASSERT(patch 4) - Address Andrew Jones's comments for v4 series - Add Andrew Jones's R-b tags in some patches - v4: https://lore.kernel.org/lkml/20210302125751.19080-1-wangyanan55@huawei.com/ v3->v4: - Add a helper to get system default hugetlb page size - Add tags of Reviewed-by of Ben in the patches - v3: https://lore.kernel.org/lkml/20210301065916.11484-1-wangyanan55@huawei.com/ v2->v3: - Add tags of Suggested-by, Reviewed-by in the patches - Add a generic micro to get hugetlb page sizes - Some changes for suggestions about v2 series - v2: https://lore.kernel.org/lkml/20210225055940.18748-1-wangyanan55@huawei.com/ v1->v2: - Add a patch to sync header files - Add helpers to get granularity of different backing src types - Some changes for suggestions about v1 series - v1: https://lore.kernel.org/lkml/20210208090841.333724-1-wangyanan55@huawei.com/ --- Yanan Wang (10): tools headers: sync headers of asm-generic/hugetlb_encode.h tools headers: Add a macro to get HUGETLB page sizes for mmap KVM: selftests: Use flag CLOCK_MONOTONIC_RAW for timing KVM: selftests: Print the errno besides error-string in TEST_ASSERT KVM: selftests: Make a generic helper to get vm guest mode strings KVM: selftests: Add a helper to get system configured THP page size KVM: selftests: Add a helper to get system default hugetlb page size KVM: selftests: List all hugetlb src types specified with page sizes KVM: selftests: Adapt vm_userspace_mem_region_add to new helpers KVM: selftests: Add a test for kvm page table code include/uapi/linux/mman.h | 2 + tools/include/asm-generic/hugetlb_encode.h | 3 + tools/include/uapi/linux/mman.h | 2 + tools/testing/selftests/kvm/.gitignore | 1 + tools/testing/selftests/kvm/Makefile | 3 + .../selftests/kvm/demand_paging_test.c | 8 +- .../selftests/kvm/dirty_log_perf_test.c | 14 +- .../testing/selftests/kvm/include/kvm_util.h | 4 +- .../testing/selftests/kvm/include/test_util.h | 21 +- .../selftests/kvm/kvm_page_table_test.c | 512 ++++++++++++++++++ tools/testing/selftests/kvm/lib/assert.c | 4 +- tools/testing/selftests/kvm/lib/kvm_util.c | 59 +- tools/testing/selftests/kvm/lib/test_util.c | 163 +++++- tools/testing/selftests/kvm/steal_time.c | 4 +- 14 files changed, 739 insertions(+), 61 deletions(-) create mode 100644 tools/testing/selftests/kvm/kvm_page_table_test.c -- 2.23.0

4 years, 3 months

4
20
0 0

[PATCH] userfaultfd/shmem: fix MCOPY_ATOMIC_CONTNUE error handling + accounting

by Axel Rasmussen

Previously, in the error path, we unconditionally removed the page from the page cache. But in the continue case, we didn't add it - it was already there because the page is used by a second (non-UFFD-registered) mapping. So, in that case, it's incorrect to remove it as the other mapping may still use it normally. For this error handling failure, trivially exercise it in the userfaultfd selftest, to detect this kind of bug in the future. Also, we previously were unconditionally calling shmem_inode_acct_block. In the continue case, however, this is incorrect, because we would have already accounted for the RAM usage when the page was originally allocated (since at this point it's already in the page cache). So, doing it in the continue case causes us to double-count. Fixes: 00da60b9d0a0 ("userfaultfd: support minor fault handling for shmem") Signed-off-by: Axel Rasmussen <axelrasmussen(a)google.com> --- mm/shmem.c | 15 ++++++++++----- tools/testing/selftests/vm/userfaultfd.c | 12 ++++++++++++ 2 files changed, 22 insertions(+), 5 deletions(-) diff --git a/mm/shmem.c b/mm/shmem.c index d2e0e81b7d2e..5ac8ea737004 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -2379,9 +2379,11 @@ int shmem_mcopy_atomic_pte(struct mm_struct *dst_mm, pmd_t *dst_pmd, int ret; pgoff_t offset, max_off; - ret = -ENOMEM; - if (!shmem_inode_acct_block(inode, 1)) - goto out; + if (!is_continue) { + ret = -ENOMEM; + if (!shmem_inode_acct_block(inode, 1)) + goto out; + } if (is_continue) { ret = -EFAULT; @@ -2389,6 +2391,7 @@ int shmem_mcopy_atomic_pte(struct mm_struct *dst_mm, pmd_t *dst_pmd, if (!page) goto out_unacct_blocks; } else if (!*pagep) { + ret = -ENOMEM; page = shmem_alloc_page(gfp, info, pgoff); if (!page) goto out_unacct_blocks; @@ -2486,12 +2489,14 @@ int shmem_mcopy_atomic_pte(struct mm_struct *dst_mm, pmd_t *dst_pmd, out_release_unlock: pte_unmap_unlock(dst_pte, ptl); ClearPageDirty(page); - delete_from_page_cache(page); + if (!is_continue) + delete_from_page_cache(page); out_release: unlock_page(page); put_page(page); out_unacct_blocks: - shmem_inode_unacct_blocks(inode, 1); + if (!is_continue) + shmem_inode_unacct_blocks(inode, 1); goto out; } #endif /* CONFIG_USERFAULTFD */ diff --git a/tools/testing/selftests/vm/userfaultfd.c b/tools/testing/selftests/vm/userfaultfd.c index f6c86b036d0f..d8541a59dae5 100644 --- a/tools/testing/selftests/vm/userfaultfd.c +++ b/tools/testing/selftests/vm/userfaultfd.c @@ -485,6 +485,7 @@ static void wp_range(int ufd, __u64 start, __u64 len, bool wp) static void continue_range(int ufd, __u64 start, __u64 len) { struct uffdio_continue req; + int ret; req.range.start = start; req.range.len = len; @@ -493,6 +494,17 @@ static void continue_range(int ufd, __u64 start, __u64 len) if (ioctl(ufd, UFFDIO_CONTINUE, &req)) err("UFFDIO_CONTINUE failed for address 0x%" PRIx64, (uint64_t)start); + + /* + * Error handling within the kernel for continue is subtly different + * from copy or zeropage, so it may be a source of bugs. Trigger an + * error (-EEXIST) on purpose, to verify doing so doesn't cause a BUG. + */ + req.mapped = 0; + ret = ioctl(ufd, UFFDIO_CONTINUE, &req); + if (ret >= 0 || req.mapped != -EEXIST) + err("failed to exercise UFFDIO_CONTINUE error handling, ret=%d, mapped=%" PRId64, + ret, req.mapped); } static void *locking_thread(void *arg) -- 2.31.0.291.g576ba9dcdaf-goog

4 years, 3 months

2
1
0 0

[PATCH] selftests/timers: remove unneeded semicolon

by Jiapeng Chong

Fix the following coccicheck warnings: ./tools/testing/selftests/timers/nanosleep.c:75:2-3: Unneeded semicolon Reported-by: Abaci Robot <abaci(a)linux.alibaba.com> Signed-off-by: Jiapeng Chong <jiapeng.chong(a)linux.alibaba.com> --- tools/testing/selftests/timers/nanosleep.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/tools/testing/selftests/timers/nanosleep.c b/tools/testing/selftests/timers/nanosleep.c index 71b5441..433a096 100644 --- a/tools/testing/selftests/timers/nanosleep.c +++ b/tools/testing/selftests/timers/nanosleep.c @@ -72,7 +72,7 @@ char *clockstring(int clockid) return "CLOCK_BOOTTIME_ALARM"; case CLOCK_TAI: return "CLOCK_TAI"; - }; + } return "UNKNOWN_CLOCKID"; } -- 1.8.3.1

4 years, 3 months

2
1
0 0

[PATCH] selftests/timers: Fix spelling mistake "clocksourc" -> "clocksource"

by Colin King

From: Colin Ian King <colin.king(a)canonical.com> There is a spelling mistake in a comment. Fix it. Signed-off-by: Colin Ian King <colin.king(a)canonical.com> --- tools/testing/selftests/timers/clocksource-switch.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/tools/testing/selftests/timers/clocksource-switch.c b/tools/testing/selftests/timers/clocksource-switch.c index bfc974b4572d..2d66abd877e6 100644 --- a/tools/testing/selftests/timers/clocksource-switch.c +++ b/tools/testing/selftests/timers/clocksource-switch.c @@ -3,7 +3,7 @@ * (C) Copyright IBM 2012 * Licensed under the GPLv2 * - * NOTE: This is a meta-test which quickly changes the clocksourc and + * NOTE: This is a meta-test which quickly changes the clocksource and * then uses other tests to detect problems. Thus this test requires * that the inconsistency-check and nanosleep tests be present in the * same directory it is run from. -- 2.30.2

4 years, 3 months

3
2
0 0

[PATCH v5] selftests: fix prepending $(OUTPUT) to $(TEST_PROGS)

by Ilya Leoshkevich

Currently the following command produces an error message: linux# make kselftest TARGETS=bpf O=/mnt/linux-build # selftests: bpf: test_libbpf.sh # ./test_libbpf.sh: line 23: ./test_libbpf_open: No such file or directory # test_libbpf: failed at file test_l4lb.o # selftests: test_libbpf [FAILED] The error message might not affect the return code of make, therefore one needs to grep make output in order to detect it. This is not the only instance of the same underlying problem; any test with more than one element in $(TEST_PROGS) fails the same way. Another example: linux# make O=/mnt/linux-build TARGETS=splice kselftest [...] # ./short_splice_read.sh: 15: ./splice_read: not found # FAIL: /sys/module/test_module/sections/.init.text 2 not ok 2 selftests: splice: short_splice_read.sh # exit=1 The current logic prepends $(OUTPUT) only to the first member of $(TEST_PROGS). After that, run_one() does cd `dirname $TEST` For all tests except the first one, `dirname $TEST` is ., which means they cannot access the files generated in $(OUTPUT). Fix by using $(addprefix) to prepend $(OUTPUT)/ to each member of $(TEST_PROGS). Fixes: 1a940687e424 ("selftests: lib.mk: copy test scripts and test files for make O=dir run") Signed-off-by: Ilya Leoshkevich <iii(a)linux.ibm.com> --- v1->v2: - Append / to $(OUTPUT). - Use $(addprefix) instead of $(foreach). v2->v3: - Split the patch in two. - Improve the commit message. v3: https://lore.kernel.org/linux-kselftest/20191024121347.22189-1-iii@linux.ib… v3->v4: - Drop the first patch. - Add a note regarding make return code to the commit message. v4: https://lore.kernel.org/linux-kselftest/20191115150428.61131-1-iii@linux.ib… v4->v5: - Add another reproducer to the commit message. tools/testing/selftests/lib.mk | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/tools/testing/selftests/lib.mk b/tools/testing/selftests/lib.mk index a5ce26d548e4..be17462fe146 100644 --- a/tools/testing/selftests/lib.mk +++ b/tools/testing/selftests/lib.mk @@ -74,7 +74,8 @@ ifdef building_out_of_srctree rsync -aq $(TEST_PROGS) $(TEST_PROGS_EXTENDED) $(TEST_FILES) $(OUTPUT); \ fi @if [ "X$(TEST_PROGS)" != "X" ]; then \ - $(call RUN_TESTS, $(TEST_GEN_PROGS) $(TEST_CUSTOM_PROGS) $(OUTPUT)/$(TEST_PROGS)) ; \ + $(call RUN_TESTS, $(TEST_GEN_PROGS) $(TEST_CUSTOM_PROGS) \ + $(addprefix $(OUTPUT)/,$(TEST_PROGS))) ; \ else \ $(call RUN_TESTS, $(TEST_GEN_PROGS) $(TEST_CUSTOM_PROGS)); \ fi -- 2.29.2

4 years, 3 months

2
1
0 0

[PATCH v6 0/8] Fork brute force attack mitigation

by John Wood

Attacks against vulnerable userspace applications with the purpose to break ASLR or bypass canaries traditionally use some level of brute force with the help of the fork system call. This is possible since when creating a new process using fork its memory contents are the same as those of the parent process (the process that called the fork system call). So, the attacker can test the memory infinite times to find the correct memory values or the correct memory addresses without worrying about crashing the application. Based on the above scenario it would be nice to have this detected and mitigated, and this is the goal of this patch serie. Specifically the following attacks are expected to be detected: 1.- Launching (fork()/exec()) a setuid/setgid process repeatedly until a desirable memory layout is got (e.g. Stack Clash). 2.- Connecting to an exec()ing network daemon (e.g. xinetd) repeatedly until a desirable memory layout is got (e.g. what CTFs do for simple network service). 3.- Launching processes without exec() (e.g. Android Zygote) and exposing state to attack a sibling. 4.- Connecting to a fork()ing network daemon (e.g. apache) repeatedly until the previously shared memory layout of all the other children is exposed (e.g. kind of related to HeartBleed). In each case, a privilege boundary has been crossed: Case 1: setuid/setgid process Case 2: network to local Case 3: privilege changes Case 4: network to local So, what will really be detected are fork/exec brute force attacks that cross any of the commented bounds. The implementation details and comparison against other existing implementations can be found in the "Documentation" patch. Knowing all this information I will explain now the different patches: The 1/8 patch defines a new LSM hook to get the fatal signal of a task. This will be useful during the attack detection phase. The 2/8 patch defines a new LSM and manages the statistical data shared by all the fork hierarchy processes. The 3/8 patch detects a fork/exec brute force attack. The 4/8 patch narrows the detection taken into account the privilege boundary crossing. The 5/8 patch mitigates a brute force attack. The 6/8 patch adds self-tests to validate the Brute LSM expectations. The 7/8 patch adds the documentation to explain this implementation. The 8/8 patch updates the maintainers file. This patch serie is a task of the KSPP [1] and can also be accessed from my github tree [2] in the "brute_v6" branch. [1] https://github.com/KSPP/linux/issues/39 [2] https://github.com/johwood/linux/ The previous versions can be found in: RFC https://lore.kernel.org/kernel-hardening/20200910202107.3799376-1-keescook@… Version 2 https://lore.kernel.org/kernel-hardening/20201025134540.3770-1-john.wood@gm… Version 3 https://lore.kernel.org/lkml/20210221154919.68050-1-john.wood@gmx.com/ Version 4 https://lore.kernel.org/lkml/20210227150956.6022-1-john.wood@gmx.com/ Version 5 https://lore.kernel.org/kernel-hardening/20210227153013.6747-1-john.wood@gm… Changelog RFC -> v2 ------------------- - Rename this feature with a more suitable name (Jann Horn, Kees Cook). - Convert the code to an LSM (Kees Cook). - Add locking to avoid data races (Jann Horn). - Add a new LSM hook to get the fatal signal of a task (Jann Horn, Kees Cook). - Add the last crashes timestamps list to avoid false positives in the attack detection (Jann Horn). - Use "period" instead of "rate" (Jann Horn). - Other minor changes suggested (Jann Horn, Kees Cook). Changelog v2 -> v3 ------------------ - Compute the application crash period on an on-going basis (Kees Cook). - Detect a brute force attack through the execve system call (Kees Cook). - Detect an slow brute force attack (Randy Dunlap). - Fine tuning the detection taken into account privilege boundary crossing (Kees Cook). - Taken into account only fatal signals delivered by the kernel (Kees Cook). - Remove the sysctl attributes to fine tuning the detection (Kees Cook). - Remove the prctls to allow per process enabling/disabling (Kees Cook). - Improve the documentation (Kees Cook). - Fix some typos in the documentation (Randy Dunlap). - Add self-test to validate the expectations (Kees Cook). Changelog v3 -> v4 ------------------ - Fix all the warnings shown by the tool "scripts/kernel-doc" (Randy Dunlap). Changelog v4 -> v5 ------------------ - Fix some typos (Randy Dunlap). Changelog v5 -> v6 ------------------ - Fix a reported deadlock (kernel test robot). - Add high level details to the documentation (Andi Kleen). Any constructive comments are welcome. Thanks. John Wood (8): security: Add LSM hook at the point where a task gets a fatal signal security/brute: Define a LSM and manage statistical data securtiy/brute: Detect a brute force attack security/brute: Fine tuning the attack detection security/brute: Mitigate a brute force attack selftests/brute: Add tests for the Brute LSM Documentation: Add documentation for the Brute LSM MAINTAINERS: Add a new entry for the Brute LSM Documentation/admin-guide/LSM/Brute.rst | 278 ++++++ Documentation/admin-guide/LSM/index.rst | 1 + MAINTAINERS | 7 + include/linux/lsm_hook_defs.h | 1 + include/linux/lsm_hooks.h | 4 + include/linux/security.h | 4 + kernel/signal.c | 1 + security/Kconfig | 11 +- security/Makefile | 4 + security/brute/Kconfig | 13 + security/brute/Makefile | 2 + security/brute/brute.c | 1107 ++++++++++++++++++++++ security/security.c | 5 + tools/testing/selftests/Makefile | 1 + tools/testing/selftests/brute/.gitignore | 2 + tools/testing/selftests/brute/Makefile | 5 + tools/testing/selftests/brute/config | 1 + tools/testing/selftests/brute/exec.c | 44 + tools/testing/selftests/brute/test.c | 507 ++++++++++ tools/testing/selftests/brute/test.sh | 226 +++++ 20 files changed, 2219 insertions(+), 5 deletions(-) create mode 100644 Documentation/admin-guide/LSM/Brute.rst create mode 100644 security/brute/Kconfig create mode 100644 security/brute/Makefile create mode 100644 security/brute/brute.c create mode 100644 tools/testing/selftests/brute/.gitignore create mode 100644 tools/testing/selftests/brute/Makefile create mode 100644 tools/testing/selftests/brute/config create mode 100644 tools/testing/selftests/brute/exec.c create mode 100644 tools/testing/selftests/brute/test.c create mode 100755 tools/testing/selftests/brute/test.sh -- 2.25.1

4 years, 3 months

3
30
0 0

[PATCH -next] treewide: Remove duplicated include from tm-vmx-unavail.c

by Zheng Yongjun

Remove duplicated include. Reported-by: Hulk Robot <hulkci(a)huawei.com> Signed-off-by: Zheng Yongjun <zhengyongjun3(a)huawei.com> --- tools/testing/selftests/powerpc/tm/tm-vmx-unavail.c | 1 - 1 file changed, 1 deletion(-) diff --git a/tools/testing/selftests/powerpc/tm/tm-vmx-unavail.c b/tools/testing/selftests/powerpc/tm/tm-vmx-unavail.c index e2a0c07e8362..9ef37a9836ac 100644 --- a/tools/testing/selftests/powerpc/tm/tm-vmx-unavail.c +++ b/tools/testing/selftests/powerpc/tm/tm-vmx-unavail.c @@ -17,7 +17,6 @@ #include <pthread.h> #include <sys/mman.h> #include <unistd.h> -#include <pthread.h> #include "tm.h" #include "utils.h"

4 years, 3 months

2
1
0 0

[PATCH] [v2] tools: testing: Remove duplicate includes

by Wan Jiabing

sched.h has been included at line 33, so remove the duplicate one at line 36. inttypes.h has been included at line 19, so remove the duplicate one at line 23. pthread.h has been included at line 17,so remove the duplicate one at line 20. Signed-off-by: Wan Jiabing <wanjiabing(a)vivo.com> --- tools/testing/selftests/powerpc/mm/tlbie_test.c | 1 - tools/testing/selftests/powerpc/tm/tm-poison.c | 1 - tools/testing/selftests/powerpc/tm/tm-vmx-unavail.c | 1 - 3 files changed, 3 deletions(-) diff --git a/tools/testing/selftests/powerpc/mm/tlbie_test.c b/tools/testing/selftests/powerpc/mm/tlbie_test.c index f85a0938ab25..48344a74b212 100644 --- a/tools/testing/selftests/powerpc/mm/tlbie_test.c +++ b/tools/testing/selftests/powerpc/mm/tlbie_test.c @@ -33,7 +33,6 @@ #include <sched.h> #include <time.h> #include <stdarg.h> -#include <sched.h> #include <pthread.h> #include <signal.h> #include <sys/prctl.h> diff --git a/tools/testing/selftests/powerpc/tm/tm-poison.c b/tools/testing/selftests/powerpc/tm/tm-poison.c index 29e5f26af7b9..27c083a03d1f 100644 --- a/tools/testing/selftests/powerpc/tm/tm-poison.c +++ b/tools/testing/selftests/powerpc/tm/tm-poison.c @@ -20,7 +20,6 @@ #include <sched.h> #include <sys/types.h> #include <signal.h> -#include <inttypes.h> #include "tm.h" diff --git a/tools/testing/selftests/powerpc/tm/tm-vmx-unavail.c b/tools/testing/selftests/powerpc/tm/tm-vmx-unavail.c index e2a0c07e8362..9ef37a9836ac 100644 --- a/tools/testing/selftests/powerpc/tm/tm-vmx-unavail.c +++ b/tools/testing/selftests/powerpc/tm/tm-vmx-unavail.c @@ -17,7 +17,6 @@ #include <pthread.h> #include <sys/mman.h> #include <unistd.h> -#include <pthread.h> #include "tm.h" #include "utils.h" -- 2.25.1

4 years, 3 months

2
1
0 0

Re: [PATCH v31 10/12] selftests/landlock: Add user space tests

by Kees Cook

On Wed, Mar 24, 2021 at 08:15:18PM +0100, Mickaël Salaün wrote: > From: Mickaël Salaün <mic(a)linux.microsoft.com> > > Test all Landlock system calls, ptrace hooks semantic and filesystem > access-control with multiple layouts. > > Test coverage for security/landlock/ is 93.6% of lines. The code not > covered only deals with internal kernel errors (e.g. memory allocation) > and race conditions. > > Cc: James Morris <jmorris(a)namei.org> > Cc: Jann Horn <jannh(a)google.com> > Cc: Kees Cook <keescook(a)chromium.org> > Cc: Serge E. Hallyn <serge(a)hallyn.com> > Cc: Shuah Khan <shuah(a)kernel.org> > Signed-off-by: Mickaël Salaün <mic(a)linux.microsoft.com> Reviewed-by: Kees Cook <keescook(a)chromium.org> -- Kees Cook

4 years, 3 months

1
0
0 0

[PATCH v30 00/12] Landlock LSM

by Mickaël Salaün

Hi, This patch series is mainly a rebase on top of v5.12-rc3 and a synchronization with the new mount_setattr(2). A light cleanup of hook_sb_delete() and new tests are also included. The SLOC count is 1329 for security/landlock/ and 2556 for tools/testing/selftest/landlock/ . Test coverage for security/landlock/ is 93.6% of lines. The code not covered only deals with internal kernel errors (e.g. memory allocation) and race conditions. This series is being fuzzed by syzkaller (which may cover internal kernel errors), and patches are on their way: https://github.com/google/syzkaller/pull/2380 The compiled documentation is available here: https://landlock.io/linux-doc/landlock-v30/userspace-api/landlock.html This series can be applied on top of v5.12-rc3 . This can be tested with CONFIG_SECURITY_LANDLOCK, CONFIG_SAMPLE_LANDLOCK and by prepending "landlock," to CONFIG_LSM. This patch series can be found in a Git repository here: https://github.com/landlock-lsm/linux/commits/landlock-v30 This patch series seems ready for upstream and I would really appreciate final reviews. Landlock LSM ------------ The goal of Landlock is to enable to restrict ambient rights (e.g. global filesystem access) for a set of processes. Because Landlock is a stackable LSM [1], it makes possible to create safe security sandboxes as new security layers in addition to the existing system-wide access-controls. This kind of sandbox is expected to help mitigate the security impact of bugs or unexpected/malicious behaviors in user-space applications. Landlock empowers any process, including unprivileged ones, to securely restrict themselves. Landlock is inspired by seccomp-bpf but instead of filtering syscalls and their raw arguments, a Landlock rule can restrict the use of kernel objects like file hierarchies, according to the kernel semantic. Landlock also takes inspiration from other OS sandbox mechanisms: XNU Sandbox, FreeBSD Capsicum or OpenBSD Pledge/Unveil. In this current form, Landlock misses some access-control features. This enables to minimize this patch series and ease review. This series still addresses multiple use cases, especially with the combined use of seccomp-bpf: applications with built-in sandboxing, init systems, security sandbox tools and security-oriented APIs [2]. [1] https://lore.kernel.org/lkml/50db058a-7dde-441b-a7f9-f6837fe8b69f@schaufler… [2] https://lore.kernel.org/lkml/f646e1c7-33cf-333f-070c-0a40ad0468cd@digikod.n… Previous versions: v29: https://lore.kernel.org/lkml/20210225190614.2181147-1-mic@digikod.net/ v28: https://lore.kernel.org/lkml/20210202162710.657398-1-mic@digikod.net/ v27: https://lore.kernel.org/lkml/20210121205119.793296-1-mic@digikod.net/ v26: https://lore.kernel.org/lkml/20201209192839.1396820-1-mic@digikod.net/ v25: https://lore.kernel.org/lkml/20201201192322.213239-1-mic@digikod.net/ v24: https://lore.kernel.org/lkml/20201112205141.775752-1-mic@digikod.net/ v23: https://lore.kernel.org/lkml/20201103182109.1014179-1-mic@digikod.net/ v22: https://lore.kernel.org/lkml/20201027200358.557003-1-mic@digikod.net/ v21: https://lore.kernel.org/lkml/20201008153103.1155388-1-mic@digikod.net/ v20: https://lore.kernel.org/lkml/20200802215903.91936-1-mic@digikod.net/ v19: https://lore.kernel.org/lkml/20200707180955.53024-1-mic@digikod.net/ v18: https://lore.kernel.org/lkml/20200526205322.23465-1-mic@digikod.net/ v17: https://lore.kernel.org/lkml/20200511192156.1618284-1-mic@digikod.net/ v16: https://lore.kernel.org/lkml/20200416103955.145757-1-mic@digikod.net/ v15: https://lore.kernel.org/lkml/20200326202731.693608-1-mic@digikod.net/ v14: https://lore.kernel.org/lkml/20200224160215.4136-1-mic@digikod.net/ v13: https://lore.kernel.org/lkml/20191104172146.30797-1-mic@digikod.net/ v12: https://lore.kernel.org/lkml/20191031164445.29426-1-mic@digikod.net/ v11: https://lore.kernel.org/lkml/20191029171505.6650-1-mic@digikod.net/ v10: https://lore.kernel.org/lkml/20190721213116.23476-1-mic@digikod.net/ v9: https://lore.kernel.org/lkml/20190625215239.11136-1-mic@digikod.net/ v8: https://lore.kernel.org/lkml/20180227004121.3633-1-mic@digikod.net/ v7: https://lore.kernel.org/lkml/20170821000933.13024-1-mic@digikod.net/ v6: https://lore.kernel.org/lkml/20170328234650.19695-1-mic@digikod.net/ v5: https://lore.kernel.org/lkml/20170222012632.4196-1-mic@digikod.net/ v4: https://lore.kernel.org/lkml/20161026065654.19166-1-mic@digikod.net/ v3: https://lore.kernel.org/lkml/20160914072415.26021-1-mic@digikod.net/ v2: https://lore.kernel.org/lkml/1472121165-29071-1-git-send-email-mic@digikod.… v1: https://lore.kernel.org/kernel-hardening/1458784008-16277-1-git-send-email-… Casey Schaufler (1): LSM: Infrastructure management of the superblock Mickaël Salaün (11): landlock: Add object management landlock: Add ruleset and domain management landlock: Set up the security framework and manage credentials landlock: Add ptrace restrictions fs,security: Add sb_delete hook landlock: Support filesystem access-control landlock: Add syscall implementations arch: Wire up Landlock syscalls selftests/landlock: Add user space tests samples/landlock: Add a sandbox manager example landlock: Add user and kernel documentation Documentation/security/index.rst | 1 + Documentation/security/landlock.rst | 79 + Documentation/userspace-api/index.rst | 1 + Documentation/userspace-api/landlock.rst | 307 ++ MAINTAINERS | 15 + arch/Kconfig | 7 + arch/alpha/kernel/syscalls/syscall.tbl | 3 + arch/arm/tools/syscall.tbl | 3 + arch/arm64/include/asm/unistd.h | 2 +- arch/arm64/include/asm/unistd32.h | 6 + arch/ia64/kernel/syscalls/syscall.tbl | 3 + arch/m68k/kernel/syscalls/syscall.tbl | 3 + arch/microblaze/kernel/syscalls/syscall.tbl | 3 + arch/mips/kernel/syscalls/syscall_n32.tbl | 3 + arch/mips/kernel/syscalls/syscall_n64.tbl | 3 + arch/mips/kernel/syscalls/syscall_o32.tbl | 3 + arch/parisc/kernel/syscalls/syscall.tbl | 3 + arch/powerpc/kernel/syscalls/syscall.tbl | 3 + arch/s390/kernel/syscalls/syscall.tbl | 3 + arch/sh/kernel/syscalls/syscall.tbl | 3 + arch/sparc/kernel/syscalls/syscall.tbl | 3 + arch/um/Kconfig | 1 + arch/x86/entry/syscalls/syscall_32.tbl | 3 + arch/x86/entry/syscalls/syscall_64.tbl | 3 + arch/xtensa/kernel/syscalls/syscall.tbl | 3 + fs/super.c | 1 + include/linux/lsm_hook_defs.h | 1 + include/linux/lsm_hooks.h | 4 + include/linux/security.h | 4 + include/linux/syscalls.h | 7 + include/uapi/asm-generic/unistd.h | 8 +- include/uapi/linux/landlock.h | 128 + kernel/sys_ni.c | 5 + samples/Kconfig | 7 + samples/Makefile | 1 + samples/landlock/.gitignore | 1 + samples/landlock/Makefile | 13 + samples/landlock/sandboxer.c | 238 ++ security/Kconfig | 11 +- security/Makefile | 2 + security/landlock/Kconfig | 21 + security/landlock/Makefile | 4 + security/landlock/common.h | 20 + security/landlock/cred.c | 46 + security/landlock/cred.h | 58 + security/landlock/fs.c | 687 ++++ security/landlock/fs.h | 56 + security/landlock/limits.h | 21 + security/landlock/object.c | 67 + security/landlock/object.h | 91 + security/landlock/ptrace.c | 120 + security/landlock/ptrace.h | 14 + security/landlock/ruleset.c | 473 +++ security/landlock/ruleset.h | 165 + security/landlock/setup.c | 40 + security/landlock/setup.h | 18 + security/landlock/syscalls.c | 445 +++ security/security.c | 51 +- security/selinux/hooks.c | 58 +- security/selinux/include/objsec.h | 6 + security/selinux/ss/services.c | 3 +- security/smack/smack.h | 6 + security/smack/smack_lsm.c | 35 +- tools/testing/selftests/Makefile | 1 + tools/testing/selftests/landlock/.gitignore | 2 + tools/testing/selftests/landlock/Makefile | 24 + tools/testing/selftests/landlock/base_test.c | 219 ++ tools/testing/selftests/landlock/common.h | 183 ++ tools/testing/selftests/landlock/config | 7 + tools/testing/selftests/landlock/fs_test.c | 2792 +++++++++++++++++ .../testing/selftests/landlock/ptrace_test.c | 337 ++ tools/testing/selftests/landlock/true.c | 5 + 72 files changed, 6896 insertions(+), 77 deletions(-) create mode 100644 Documentation/security/landlock.rst create mode 100644 Documentation/userspace-api/landlock.rst create mode 100644 include/uapi/linux/landlock.h create mode 100644 samples/landlock/.gitignore create mode 100644 samples/landlock/Makefile create mode 100644 samples/landlock/sandboxer.c create mode 100644 security/landlock/Kconfig create mode 100644 security/landlock/Makefile create mode 100644 security/landlock/common.h create mode 100644 security/landlock/cred.c create mode 100644 security/landlock/cred.h create mode 100644 security/landlock/fs.c create mode 100644 security/landlock/fs.h create mode 100644 security/landlock/limits.h create mode 100644 security/landlock/object.c create mode 100644 security/landlock/object.h create mode 100644 security/landlock/ptrace.c create mode 100644 security/landlock/ptrace.h create mode 100644 security/landlock/ruleset.c create mode 100644 security/landlock/ruleset.h create mode 100644 security/landlock/setup.c create mode 100644 security/landlock/setup.h create mode 100644 security/landlock/syscalls.c create mode 100644 tools/testing/selftests/landlock/.gitignore create mode 100644 tools/testing/selftests/landlock/Makefile create mode 100644 tools/testing/selftests/landlock/base_test.c create mode 100644 tools/testing/selftests/landlock/common.h create mode 100644 tools/testing/selftests/landlock/config create mode 100644 tools/testing/selftests/landlock/fs_test.c create mode 100644 tools/testing/selftests/landlock/ptrace_test.c create mode 100644 tools/testing/selftests/landlock/true.c base-commit: 1e28eed17697bcf343c6743f0028cc3b5dd88bf0 -- 2.30.2

4 years, 3 months

4
43
0 0

[PATCH] userfaultfd/shmem: fix minor fault page leak

by Axel Rasmussen

This fix is analogous to Peter Xu's fix for hugetlb [0]. If we don't put_page() after getting the page out of the page cache, we leak the reference. The fix can be verified by checking /proc/meminfo and running the userfaultfd selftest in shmem mode. Without the fix, we see MemFree / MemAvailable steadily decreasing with each run of the test. With the fix, memory is correctly freed after the test program exits. Fixes: 00da60b9d0a0 ("userfaultfd: support minor fault handling for shmem") Signed-off-by: Axel Rasmussen <axelrasmussen(a)google.com> --- mm/shmem.c | 1 + 1 file changed, 1 insertion(+) diff --git a/mm/shmem.c b/mm/shmem.c index ef8c9f5e92fc..d2e0e81b7d2e 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -1831,6 +1831,7 @@ static int shmem_getpage_gfp(struct inode *inode, pgoff_t index, if (page && vma && userfaultfd_minor(vma)) { unlock_page(page); + put_page(page); *fault_type = handle_userfault(vmf, VM_UFFD_MINOR); return 0; } -- 2.31.0.rc2.261.g7f71774620-goog

4 years, 3 months

3
4
0 0

[PATCH] tools: testing: Remove duplicate include of string.h

by Wan Jiabing

string.h has been included at line 15.So we remove the duplicate one at line 17. Signed-off-by: Wan Jiabing <wanjiabing(a)vivo.com> --- tools/testing/selftests/mincore/mincore_selftest.c | 1 - 1 file changed, 1 deletion(-) diff --git a/tools/testing/selftests/mincore/mincore_selftest.c b/tools/testing/selftests/mincore/mincore_selftest.c index 5a1e85ff5d32..e54106643337 100644 --- a/tools/testing/selftests/mincore/mincore_selftest.c +++ b/tools/testing/selftests/mincore/mincore_selftest.c @@ -14,7 +14,6 @@ #include <sys/mman.h> #include <string.h> #include <fcntl.h> -#include <string.h> #include "../kselftest.h" #include "../kselftest_harness.h" -- 2.25.1

4 years, 3 months

2
1
0 0

[PATCH v6 1/2] mm: huge_memory: a new debugfs interface for splitting THP tests.

by Zi Yan

From: Zi Yan <ziy(a)nvidia.com> We did not have a direct user interface of splitting the compound page backing a THP and there is no need unless we want to expose the THP implementation details to users. Make <debugfs>/split_huge_pages accept a new command to do that. By writing "<pid>,<vaddr_start>,<vaddr_end>" to <debugfs>/split_huge_pages, THPs within the given virtual address range from the process with the given pid are split. It is used to test split_huge_page function. In addition, a selftest program is added to tools/testing/selftests/vm to utilize the interface by splitting PMD THPs and PTE-mapped THPs. This does not change the old behavior, i.e., writing 1 to the interface to split all THPs in the system. Changelog: >From v5: 1. Skipped special VMAs and other fixes. (suggested by Yang Shi) >From v4: 1. Fixed the error code return issue, spotted by kernel test robot <lkp(a)intel.com>. >From v3: 1. Factored out split huge pages in the given pid code to a separate function. 2. Added the missing put_page for not split pages. 3. pr_debug -> pr_info, make reading results simpler. >From v2: 1. Reused existing <debugfs>/split_huge_pages interface. (suggested by Yang Shi) >From v1: 1. Removed unnecessary calling to vma_migratable, spotted by kernel test robot <lkp(a)intel.com>. 2. Dropped the use of find_mm_struct and code it directly, since there is no need for the permission check in that function and the function is only available when migration is on. 3. Added some comments in the selftest program to clarify how PTE-mapped THPs are formed. Signed-off-by: Zi Yan <ziy(a)nvidia.com> Reviewed-by: Yang Shi <shy828301(a)gmail.com> --- mm/huge_memory.c | 151 ++++++++- tools/testing/selftests/vm/.gitignore | 1 + tools/testing/selftests/vm/Makefile | 1 + .../selftests/vm/split_huge_page_test.c | 318 ++++++++++++++++++ 4 files changed, 464 insertions(+), 7 deletions(-) create mode 100644 tools/testing/selftests/vm/split_huge_page_test.c diff --git a/mm/huge_memory.c b/mm/huge_memory.c index bff92dea5ab3..b653255a548e 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -7,6 +7,7 @@ #include <linux/mm.h> #include <linux/sched.h> +#include <linux/sched/mm.h> #include <linux/sched/coredump.h> #include <linux/sched/numa_balancing.h> #include <linux/highmem.h> @@ -2922,16 +2923,14 @@ static struct shrinker deferred_split_shrinker = { }; #ifdef CONFIG_DEBUG_FS -static int split_huge_pages_set(void *data, u64 val) +static void split_huge_pages_all(void) { struct zone *zone; struct page *page; unsigned long pfn, max_zone_pfn; unsigned long total = 0, split = 0; - if (val != 1) - return -EINVAL; - + pr_info("Split all THPs\n"); for_each_populated_zone(zone) { max_zone_pfn = zone_end_pfn(zone); for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++) { @@ -2959,11 +2958,149 @@ static int split_huge_pages_set(void *data, u64 val) } pr_info("%lu of %lu THP split\n", split, total); +} - return 0; +static inline bool vma_not_suitable_for_thp_split(struct vm_area_struct *vma) +{ + return vma_is_special_huge(vma) || (vma->vm_flags & VM_IO) || + is_vm_hugetlb_page(vma); } -DEFINE_DEBUGFS_ATTRIBUTE(split_huge_pages_fops, NULL, split_huge_pages_set, - "%llu\n"); + +static int split_huge_pages_pid(int pid, unsigned long vaddr_start, + unsigned long vaddr_end) +{ + int ret = 0; + struct task_struct *task; + struct mm_struct *mm; + unsigned long total = 0, split = 0; + unsigned long addr; + + vaddr_start &= PAGE_MASK; + vaddr_end &= PAGE_MASK; + + /* Find the task_struct from pid */ + rcu_read_lock(); + task = find_task_by_vpid(pid); + if (!task) { + rcu_read_unlock(); + ret = -ESRCH; + goto out; + } + get_task_struct(task); + rcu_read_unlock(); + + /* Find the mm_struct */ + mm = get_task_mm(task); + put_task_struct(task); + + if (!mm) { + ret = -EINVAL; + goto out; + } + + pr_info("Split huge pages in pid: %d, vaddr: [0x%lx - 0x%lx]\n", + pid, vaddr_start, vaddr_end); + + mmap_read_lock(mm); + /* + * always increase addr by PAGE_SIZE, since we could have a PTE page + * table filled with PTE-mapped THPs, each of which is distinct. + */ + for (addr = vaddr_start; addr < vaddr_end; addr += PAGE_SIZE) { + struct vm_area_struct *vma = find_vma(mm, addr); + unsigned int follflags; + struct page *page; + + if (!vma || addr < vma->vm_start) + break; + + /* skip special VMA and hugetlb VMA */ + if (vma_not_suitable_for_thp_split(vma)) { + addr = vma->vm_end; + continue; + } + + /* FOLL_DUMP to ignore special (like zero) pages */ + follflags = FOLL_GET | FOLL_DUMP; + page = follow_page(vma, addr, follflags); + + if (IS_ERR(page)) + continue; + if (!page) + continue; + + if (!is_transparent_hugepage(page)) + goto next; + + total++; + if (!can_split_huge_page(compound_head(page), NULL)) + goto next; + + if (!trylock_page(page)) + goto next; + + if (!split_huge_page(page)) + split++; + + unlock_page(page); +next: + put_page(page); + } + mmap_read_unlock(mm); + mmput(mm); + + pr_info("%lu of %lu THP split\n", split, total); + +out: + return ret; +} + +#define MAX_INPUT_BUF_SZ 255 + +static ssize_t split_huge_pages_write(struct file *file, const char __user *buf, + size_t count, loff_t *ppops) +{ + static DEFINE_MUTEX(split_debug_mutex); + ssize_t ret; + char input_buf[MAX_INPUT_BUF_SZ]; /* hold pid, start_vaddr, end_vaddr */ + int pid; + unsigned long vaddr_start, vaddr_end; + + ret = mutex_lock_interruptible(&split_debug_mutex); + if (ret) + return ret; + + ret = -EFAULT; + + memset(input_buf, 0, MAX_INPUT_BUF_SZ); + if (copy_from_user(input_buf, buf, min_t(size_t, count, MAX_INPUT_BUF_SZ))) + goto out; + + input_buf[MAX_INPUT_BUF_SZ - 1] = '\0'; + ret = sscanf(input_buf, "%d,0x%lx,0x%lx", &pid, &vaddr_start, &vaddr_end); + if (ret == 1 && pid == 1) { + split_huge_pages_all(); + ret = strlen(input_buf); + goto out; + } else if (ret != 3) { + ret = -EINVAL; + goto out; + } + + ret = split_huge_pages_pid(pid, vaddr_start, vaddr_end); + if (!ret) + ret = strlen(input_buf); +out: + mutex_unlock(&split_debug_mutex); + return ret; + +} + +static const struct file_operations split_huge_pages_fops = { + .owner = THIS_MODULE, + .write = split_huge_pages_write, + .llseek = no_llseek, +}; static int __init split_huge_pages_debugfs(void) { diff --git a/tools/testing/selftests/vm/.gitignore b/tools/testing/selftests/vm/.gitignore index 9a35c3f6a557..1f651e85ed60 100644 --- a/tools/testing/selftests/vm/.gitignore +++ b/tools/testing/selftests/vm/.gitignore @@ -22,3 +22,4 @@ map_fixed_noreplace write_to_hugetlbfs hmm-tests local_config.* +split_huge_page_test diff --git a/tools/testing/selftests/vm/Makefile b/tools/testing/selftests/vm/Makefile index d42115e4284d..4cbc91d6869f 100644 --- a/tools/testing/selftests/vm/Makefile +++ b/tools/testing/selftests/vm/Makefile @@ -42,6 +42,7 @@ TEST_GEN_FILES += on-fault-limit TEST_GEN_FILES += thuge-gen TEST_GEN_FILES += transhuge-stress TEST_GEN_FILES += userfaultfd +TEST_GEN_FILES += split_huge_page_test ifeq ($(MACHINE),x86_64) CAN_BUILD_I386 := $(shell ./../x86/check_cc.sh $(CC) ../x86/trivial_32bit_program.c -m32) diff --git a/tools/testing/selftests/vm/split_huge_page_test.c b/tools/testing/selftests/vm/split_huge_page_test.c new file mode 100644 index 000000000000..2c0c18e60c57 --- /dev/null +++ b/tools/testing/selftests/vm/split_huge_page_test.c @@ -0,0 +1,318 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * A test of splitting PMD THPs and PTE-mapped THPs from a specified virtual + * address range in a process via <debugfs>/split_huge_pages interface. + */ + +#define _GNU_SOURCE +#include <stdio.h> +#include <stdlib.h> +#include <unistd.h> +#include <inttypes.h> +#include <string.h> +#include <fcntl.h> +#include <sys/mman.h> +#include <malloc.h> +#include <stdbool.h> + +uint64_t pagesize; +unsigned int pageshift; +uint64_t pmd_pagesize; + +#define PMD_SIZE_PATH "/sys/kernel/mm/transparent_hugepage/hpage_pmd_size" +#define SPLIT_DEBUGFS "/sys/kernel/debug/split_huge_pages" +#define SMAP_PATH "/proc/self/smaps" +#define INPUT_MAX 80 + +#define PFN_MASK ((1UL<<55)-1) +#define KPF_THP (1UL<<22) + +int is_backed_by_thp(char *vaddr, int pagemap_file, int kpageflags_file) +{ + uint64_t paddr; + uint64_t page_flags; + + if (pagemap_file) { + pread(pagemap_file, &paddr, sizeof(paddr), + ((long)vaddr >> pageshift) * sizeof(paddr)); + + if (kpageflags_file) { + pread(kpageflags_file, &page_flags, sizeof(page_flags), + (paddr & PFN_MASK) * sizeof(page_flags)); + + return !!(page_flags & KPF_THP); + } + } + return 0; +} + + +static uint64_t read_pmd_pagesize(void) +{ + int fd; + char buf[20]; + ssize_t num_read; + + fd = open(PMD_SIZE_PATH, O_RDONLY); + if (fd == -1) { + perror("Open hpage_pmd_size failed"); + exit(EXIT_FAILURE); + } + num_read = read(fd, buf, 19); + if (num_read < 1) { + close(fd); + perror("Read hpage_pmd_size failed"); + exit(EXIT_FAILURE); + } + buf[num_read] = '\0'; + close(fd); + + return strtoul(buf, NULL, 10); +} + +static int write_file(const char *path, const char *buf, size_t buflen) +{ + int fd; + ssize_t numwritten; + + fd = open(path, O_WRONLY); + if (fd == -1) + return 0; + + numwritten = write(fd, buf, buflen - 1); + close(fd); + if (numwritten < 1) + return 0; + + return (unsigned int) numwritten; +} + +static void write_debugfs(int pid, uint64_t vaddr_start, uint64_t vaddr_end) +{ + char input[INPUT_MAX]; + int ret; + + ret = snprintf(input, INPUT_MAX, "%d,0x%lx,0x%lx", pid, vaddr_start, + vaddr_end); + if (ret >= INPUT_MAX) { + printf("%s: Debugfs input is too long\n", __func__); + exit(EXIT_FAILURE); + } + + if (!write_file(SPLIT_DEBUGFS, input, ret + 1)) { + perror(SPLIT_DEBUGFS); + exit(EXIT_FAILURE); + } +} + +#define MAX_LINE_LENGTH 500 + +static bool check_for_pattern(FILE *fp, const char *pattern, char *buf) +{ + while (fgets(buf, MAX_LINE_LENGTH, fp) != NULL) { + if (!strncmp(buf, pattern, strlen(pattern))) + return true; + } + return false; +} + +static uint64_t check_huge(void *addr) +{ + uint64_t thp = 0; + int ret; + FILE *fp; + char buffer[MAX_LINE_LENGTH]; + char addr_pattern[MAX_LINE_LENGTH]; + + ret = snprintf(addr_pattern, MAX_LINE_LENGTH, "%08lx-", + (unsigned long) addr); + if (ret >= MAX_LINE_LENGTH) { + printf("%s: Pattern is too long\n", __func__); + exit(EXIT_FAILURE); + } + + + fp = fopen(SMAP_PATH, "r"); + if (!fp) { + printf("%s: Failed to open file %s\n", __func__, SMAP_PATH); + exit(EXIT_FAILURE); + } + if (!check_for_pattern(fp, addr_pattern, buffer)) + goto err_out; + + /* + * Fetch the AnonHugePages: in the same block and check the number of + * hugepages. + */ + if (!check_for_pattern(fp, "AnonHugePages:", buffer)) + goto err_out; + + if (sscanf(buffer, "AnonHugePages:%10ld kB", &thp) != 1) { + printf("Reading smap error\n"); + exit(EXIT_FAILURE); + } + +err_out: + fclose(fp); + return thp; +} + +void split_pmd_thp(void) +{ + char *one_page; + size_t len = 4 * pmd_pagesize; + uint64_t thp_size; + size_t i; + + one_page = memalign(pmd_pagesize, len); + + if (!one_page) { + printf("Fail to allocate memory\n"); + exit(EXIT_FAILURE); + } + + madvise(one_page, len, MADV_HUGEPAGE); + + for (i = 0; i < len; i++) + one_page[i] = (char)i; + + thp_size = check_huge(one_page); + if (!thp_size) { + printf("No THP is allocated\n"); + exit(EXIT_FAILURE); + } + + /* split all THPs */ + write_debugfs(getpid(), (uint64_t)one_page, (uint64_t)one_page + len); + + for (i = 0; i < len; i++) + if (one_page[i] != (char)i) { + printf("%ld byte corrupted\n", i); + exit(EXIT_FAILURE); + } + + + thp_size = check_huge(one_page); + if (thp_size) { + printf("Still %ld kB AnonHugePages not split\n", thp_size); + exit(EXIT_FAILURE); + } + + printf("Split huge pages successful\n"); + free(one_page); +} + +void split_pte_mapped_thp(void) +{ + char *one_page, *pte_mapped, *pte_mapped2; + size_t len = 4 * pmd_pagesize; + uint64_t thp_size; + size_t i; + const char *pagemap_template = "/proc/%d/pagemap"; + const char *kpageflags_proc = "/proc/kpageflags"; + char pagemap_proc[255]; + int pagemap_fd; + int kpageflags_fd; + + if (snprintf(pagemap_proc, 255, pagemap_template, getpid()) < 0) { + perror("get pagemap proc error"); + exit(EXIT_FAILURE); + } + pagemap_fd = open(pagemap_proc, O_RDONLY); + + if (pagemap_fd == -1) { + perror("read pagemap:"); + exit(EXIT_FAILURE); + } + + kpageflags_fd = open(kpageflags_proc, O_RDONLY); + + if (kpageflags_fd == -1) { + perror("read kpageflags:"); + exit(EXIT_FAILURE); + } + + one_page = mmap((void *)(1UL << 30), len, PROT_READ | PROT_WRITE, + MAP_ANONYMOUS | MAP_PRIVATE, -1, 0); + + madvise(one_page, len, MADV_HUGEPAGE); + + for (i = 0; i < len; i++) + one_page[i] = (char)i; + + thp_size = check_huge(one_page); + if (!thp_size) { + printf("No THP is allocated\n"); + exit(EXIT_FAILURE); + } + + /* remap the first pagesize of first THP */ + pte_mapped = mremap(one_page, pagesize, pagesize, MREMAP_MAYMOVE); + + /* remap the Nth pagesize of Nth THP */ + for (i = 1; i < 4; i++) { + pte_mapped2 = mremap(one_page + pmd_pagesize * i + pagesize * i, + pagesize, pagesize, + MREMAP_MAYMOVE|MREMAP_FIXED, + pte_mapped + pagesize * i); + if (pte_mapped2 == (char *)-1) { + perror("mremap failed"); + exit(EXIT_FAILURE); + } + } + + /* smap does not show THPs after mremap, use kpageflags instead */ + thp_size = 0; + for (i = 0; i < pagesize * 4; i++) + if (i % pagesize == 0 && + is_backed_by_thp(&pte_mapped[i], pagemap_fd, kpageflags_fd)) + thp_size++; + + if (thp_size != 4) { + printf("Some THPs are missing during mremap\n"); + exit(EXIT_FAILURE); + } + + /* split all remapped THPs */ + write_debugfs(getpid(), (uint64_t)pte_mapped, + (uint64_t)pte_mapped + pagesize * 4); + + /* smap does not show THPs after mremap, use kpageflags instead */ + thp_size = 0; + for (i = 0; i < pagesize * 4; i++) { + if (pte_mapped[i] != (char)i) { + printf("%ld byte corrupted\n", i); + exit(EXIT_FAILURE); + } + if (i % pagesize == 0 && + is_backed_by_thp(&pte_mapped[i], pagemap_fd, kpageflags_fd)) + thp_size++; + } + + if (thp_size) { + printf("Still %ld THPs not split\n", thp_size); + exit(EXIT_FAILURE); + } + + printf("Split PTE-mapped huge pages successful\n"); + munmap(one_page, len); + close(pagemap_fd); + close(kpageflags_fd); +} + +int main(int argc, char **argv) +{ + if (geteuid() != 0) { + printf("Please run the benchmark as root\n"); + exit(EXIT_FAILURE); + } + + pagesize = getpagesize(); + pageshift = ffs(pagesize) - 1; + pmd_pagesize = read_pmd_pagesize(); + + split_pmd_thp(); + split_pte_mapped_thp(); + + return 0; +} -- 2.30.2

4 years, 3 months

3
3
0 0

[PATCH v6] selftests/x86: Use getauxval() to simplify the code in sgx

by Tianjia Zhang

Simplify the sgx code implemntation by using library function getauxval() instead of a custom function to get the base address of vDSO. Signed-off-by: Tianjia Zhang <tianjia.zhang(a)linux.alibaba.com> Reviewed-by: Jarkko Sakkinen <jarkko(a)kernel.org> Acked-by: Shuah Khan <skhan(a)linuxfoundation.org> --- tools/testing/selftests/sgx/main.c | 24 ++++-------------------- 1 file changed, 4 insertions(+), 20 deletions(-) diff --git a/tools/testing/selftests/sgx/main.c b/tools/testing/selftests/sgx/main.c index 724cec700926..5167505fbb46 100644 --- a/tools/testing/selftests/sgx/main.c +++ b/tools/testing/selftests/sgx/main.c @@ -15,6 +15,7 @@ #include <sys/stat.h> #include <sys/time.h> #include <sys/types.h> +#include <sys/auxv.h> #include "defines.h" #include "main.h" #include "../kselftest.h" @@ -28,24 +29,6 @@ struct vdso_symtab { Elf64_Word *elf_hashtab; }; -static void *vdso_get_base_addr(char *envp[]) -{ - Elf64_auxv_t *auxv; - int i; - - for (i = 0; envp[i]; i++) - ; - - auxv = (Elf64_auxv_t *)&envp[i + 1]; - - for (i = 0; auxv[i].a_type != AT_NULL; i++) { - if (auxv[i].a_type == AT_SYSINFO_EHDR) - return (void *)auxv[i].a_un.a_val; - } - - return NULL; -} - static Elf64_Dyn *vdso_get_dyntab(void *addr) { Elf64_Ehdr *ehdr = addr; @@ -162,7 +145,7 @@ static int user_handler(long rdi, long rsi, long rdx, long ursp, long r8, long r return 0; } -int main(int argc, char *argv[], char *envp[]) +int main(int argc, char *argv[]) { struct sgx_enclave_run run; struct vdso_symtab symtab; @@ -203,7 +186,8 @@ int main(int argc, char *argv[], char *envp[]) memset(&run, 0, sizeof(run)); run.tcs = encl.encl_base; - addr = vdso_get_base_addr(envp); + /* Get vDSO base address */ + addr = (void *)getauxval(AT_SYSINFO_EHDR); if (!addr) goto err; -- 2.19.1.3.ge56e4f7

4 years, 3 months

3
5
0 0

[PATCH RFC v2 0/8] Add support for synchronous signals on perf events

by Marco Elver

The perf subsystem today unifies various tracing and monitoring features, from both software and hardware. One benefit of the perf subsystem is automatically inheriting events to child tasks, which enables process-wide events monitoring with low overheads. By default perf events are non-intrusive, not affecting behaviour of the tasks being monitored. For certain use-cases, however, it makes sense to leverage the generality of the perf events subsystem and optionally allow the tasks being monitored to receive signals on events they are interested in. This patch series adds the option to synchronously signal user space on events. To better support process-wide synchronous self-monitoring, without events propagating to children that do not share the current process's shared environment, two pre-requisite patches are added to optionally restrict inheritance to CLONE_THREAD, and remove events on exec (without affecting the parent). Examples how to use these features can be found in the two kselftests at the end of the series. The kselftests verify and stress test the basic functionality. The discussion at [1] led to the changes proposed in this series. The approach taken in patch "Add support for SIGTRAP on perf events" to use 'event_limit' to trigger the signal was kindly suggested by Peter Zijlstra in [2]. [1] https://lore.kernel.org/lkml/CACT4Y+YPrXGw+AtESxAgPyZ84TYkNZdP0xpocX2jwVAbZ… [2] https://lore.kernel.org/lkml/YBv3rAT566k+6zjg@hirez.programming.kicks-ass.n… Motivation and example uses: 1. Our immediate motivation is low-overhead sampling-based race detection for user space [3]. By using perf_event_open() at process initialization, we can create hardware breakpoint/watchpoint events that are propagated automatically to all threads in a process. As far as we are aware, today no existing kernel facility (such as ptrace) allows us to set up process-wide watchpoints with minimal overheads (that are comparable to mprotect() of whole pages). [3] https://llvm.org/devmtg/2020-09/slides/Morehouse-GWP-Tsan.pdf 2. Other low-overhead error detectors that rely on detecting accesses to certain memory locations or code, process-wide and also only in a specific set of subtasks or threads. Other ideas for use-cases we found interesting, but should only illustrate the range of potential to further motivate the utility (we're sure there are more): 3. Code hot patching without full stop-the-world. Specifically, by setting a code breakpoint to entry to the patched routine, then send signals to threads and check that they are not in the routine, but without stopping them further. If any of the threads will enter the routine, it will receive SIGTRAP and pause. 4. Safepoints without mprotect(). Some Java implementations use "load from a known memory location" as a safepoint. When threads need to be stopped, the page containing the location is mprotect()ed and threads get a signal. This could be replaced with a watchpoint, which does not require a whole page nor DTLB shootdowns. 5. Threads receiving signals on performance events to throttle/unthrottle themselves. 6. Tracking data flow globally. --- v2: * Patch "Support only inheriting events if cloned with CLONE_THREAD" added to series. * Patch "Add support for event removal on exec" added to series. * Patch "Add kselftest for process-wide sigtrap handling" added to series. * Patch "Add kselftest for remove_on_exec" added to series. * Implicitly restrict inheriting events if sigtrap, but the child was cloned with CLONE_CLEAR_SIGHAND, because it is not generally safe if the child cleared all signal handlers to continue sending SIGTRAP. * Various minor fixes (see details in patches). v1: https://lkml.kernel.org/r/20210223143426.2412737-1-elver@google.com Marco Elver (8): perf/core: Apply PERF_EVENT_IOC_MODIFY_ATTRIBUTES to children perf/core: Support only inheriting events if cloned with CLONE_THREAD perf/core: Add support for event removal on exec signal: Introduce TRAP_PERF si_code and si_perf to siginfo perf/core: Add support for SIGTRAP on perf events perf/core: Add breakpoint information to siginfo on SIGTRAP selftests/perf: Add kselftest for process-wide sigtrap handling selftests/perf: Add kselftest for remove_on_exec arch/m68k/kernel/signal.c | 3 + arch/x86/kernel/signal_compat.c | 5 +- fs/signalfd.c | 4 + include/linux/compat.h | 2 + include/linux/perf_event.h | 5 +- include/linux/signal.h | 1 + include/uapi/asm-generic/siginfo.h | 6 +- include/uapi/linux/perf_event.h | 5 +- include/uapi/linux/signalfd.h | 4 +- kernel/events/core.c | 130 ++++++++- kernel/fork.c | 2 +- kernel/signal.c | 11 + .../testing/selftests/perf_events/.gitignore | 3 + tools/testing/selftests/perf_events/Makefile | 6 + tools/testing/selftests/perf_events/config | 1 + .../selftests/perf_events/remove_on_exec.c | 256 ++++++++++++++++++ tools/testing/selftests/perf_events/settings | 1 + .../selftests/perf_events/sigtrap_threads.c | 202 ++++++++++++++ 18 files changed, 632 insertions(+), 15 deletions(-) create mode 100644 tools/testing/selftests/perf_events/.gitignore create mode 100644 tools/testing/selftests/perf_events/Makefile create mode 100644 tools/testing/selftests/perf_events/config create mode 100644 tools/testing/selftests/perf_events/remove_on_exec.c create mode 100644 tools/testing/selftests/perf_events/settings create mode 100644 tools/testing/selftests/perf_events/sigtrap_threads.c -- 2.30.1.766.gb4fecdf3b7-goog

4 years, 3 months

3
23
0 0

[PATCH] kselftest: arm64: Add BTI tests

by Mark Brown

Add some tests that verify that BTI functions correctly for static binaries built with and without BTI support, verifying that SIGILL is generated when expected and is not generated in other situations. Since BTI support is still being rolled out in distributions these tests are built entirely free standing, no libc support is used at all so none of the standard helper functions for kselftest can be used and we open code everything. This also means we aren't testing the kernel support for the dynamic linker, though the test program can be readily adapted for that once it becomes something that we can reliably build and run. These tests were originally written by Dave Martin, I've adapted them for kselftest, mainly around the build system and the output format. Signed-off-by: Mark Brown <broonie(a)kernel.org> Cc: Dave Martin <Dave.Martin(a)arm.com> --- tools/testing/selftests/arm64/Makefile | 2 +- tools/testing/selftests/arm64/bti/.gitignore | 2 + tools/testing/selftests/arm64/bti/Makefile | 61 +++++ tools/testing/selftests/arm64/bti/assembler.h | 80 ++++++ tools/testing/selftests/arm64/bti/btitest.h | 23 ++ tools/testing/selftests/arm64/bti/compiler.h | 21 ++ .../selftests/arm64/bti/gen/.gitignore | 2 + tools/testing/selftests/arm64/bti/signal.c | 37 +++ tools/testing/selftests/arm64/bti/signal.h | 21 ++ tools/testing/selftests/arm64/bti/start.S | 14 ++ tools/testing/selftests/arm64/bti/syscall.S | 23 ++ tools/testing/selftests/arm64/bti/system.c | 22 ++ tools/testing/selftests/arm64/bti/system.h | 28 +++ tools/testing/selftests/arm64/bti/test.c | 234 ++++++++++++++++++ tools/testing/selftests/arm64/bti/teststubs.S | 39 +++ .../testing/selftests/arm64/bti/trampoline.S | 29 +++ 16 files changed, 637 insertions(+), 1 deletion(-) create mode 100644 tools/testing/selftests/arm64/bti/.gitignore create mode 100644 tools/testing/selftests/arm64/bti/Makefile create mode 100644 tools/testing/selftests/arm64/bti/assembler.h create mode 100644 tools/testing/selftests/arm64/bti/btitest.h create mode 100644 tools/testing/selftests/arm64/bti/compiler.h create mode 100644 tools/testing/selftests/arm64/bti/gen/.gitignore create mode 100644 tools/testing/selftests/arm64/bti/signal.c create mode 100644 tools/testing/selftests/arm64/bti/signal.h create mode 100644 tools/testing/selftests/arm64/bti/start.S create mode 100644 tools/testing/selftests/arm64/bti/syscall.S create mode 100644 tools/testing/selftests/arm64/bti/system.c create mode 100644 tools/testing/selftests/arm64/bti/system.h create mode 100644 tools/testing/selftests/arm64/bti/test.c create mode 100644 tools/testing/selftests/arm64/bti/teststubs.S create mode 100644 tools/testing/selftests/arm64/bti/trampoline.S diff --git a/tools/testing/selftests/arm64/Makefile b/tools/testing/selftests/arm64/Makefile index 2c9d012797a7..ced910fb4019 100644 --- a/tools/testing/selftests/arm64/Makefile +++ b/tools/testing/selftests/arm64/Makefile @@ -4,7 +4,7 @@ ARCH ?= $(shell uname -m 2>/dev/null || echo not) ifneq (,$(filter $(ARCH),aarch64 arm64)) -ARM64_SUBTARGETS ?= tags signal pauth fp mte +ARM64_SUBTARGETS ?= tags signal pauth fp mte bti else ARM64_SUBTARGETS := endif diff --git a/tools/testing/selftests/arm64/bti/.gitignore b/tools/testing/selftests/arm64/bti/.gitignore new file mode 100644 index 000000000000..73869fabada4 --- /dev/null +++ b/tools/testing/selftests/arm64/bti/.gitignore @@ -0,0 +1,2 @@ +btitest +nobtitest diff --git a/tools/testing/selftests/arm64/bti/Makefile b/tools/testing/selftests/arm64/bti/Makefile new file mode 100644 index 000000000000..73e013c082a6 --- /dev/null +++ b/tools/testing/selftests/arm64/bti/Makefile @@ -0,0 +1,61 @@ +# SPDX-License-Identifier: GPL-2.0 + +TEST_GEN_PROGS := btitest nobtitest + +PROGS := $(patsubst %,gen/%,$(TEST_GEN_PROGS)) + +# These tests are built as freestanding binaries since otherwise BTI +# support in ld.so is required which is not currently widespread; when +# it is available it will still be useful to test this separately as the +# cases for statically linked and dynamically lined binaries are +# slightly different. + +CFLAGS_NOBTI = -DBTI=0 +CFLAGS_BTI = -mbranch-protection=standard -DBTI=1 + +CFLAGS_COMMON = -ffreestanding -Wall -Wextra $(CFLAGS) + +BTI_CC_COMMAND = $(CC) $(CFLAGS_BTI) $(CFLAGS_COMMON) -c -o $@ $< +NOBTI_CC_COMMAND = $(CC) $(CFLAGS_NOBTI) $(CFLAGS_COMMON) -c -o $@ $< + +%-bti.o: %.c + $(BTI_CC_COMMAND) + +%-bti.o: %.S + $(BTI_CC_COMMAND) + +%-nobti.o: %.c + $(NOBTI_CC_COMMAND) + +%-nobti.o: %.S + $(NOBTI_CC_COMMAND) + +BTI_OBJS = \ + test-bti.o \ + signal-bti.o \ + start-bti.o \ + syscall-bti.o \ + system-bti.o \ + teststubs-bti.o \ + trampoline-bti.o +gen/btitest: $(BTI_OBJS) + $(CC) $(CFLAGS_BTI) $(CFLAGS_COMMON) -nostdlib -o $@ $^ + +NOBTI_OBJS = \ + test-nobti.o \ + signal-nobti.o \ + start-nobti.o \ + syscall-nobti.o \ + system-nobti.o \ + teststubs-nobti.o \ + trampoline-nobti.o +gen/nobtitest: $(NOBTI_OBJS) + $(CC) $(CFLAGS_BTI) $(CFLAGS_COMMON) -nostdlib -o $@ $^ + +# Including KSFT lib.mk here will also mangle the TEST_GEN_PROGS list +# to account for any OUTPUT target-dirs optionally provided by +# the toplevel makefile +include ../../lib.mk + +$(TEST_GEN_PROGS): $(PROGS) + cp $(PROGS) $(OUTPUT)/ diff --git a/tools/testing/selftests/arm64/bti/assembler.h b/tools/testing/selftests/arm64/bti/assembler.h new file mode 100644 index 000000000000..04e7b72880ef --- /dev/null +++ b/tools/testing/selftests/arm64/bti/assembler.h @@ -0,0 +1,80 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (C) 2019 Arm Limited + * Original author: Dave Martin <Dave.Martin(a)arm.com> + */ + +#ifndef ASSEMBLER_H +#define ASSEMBLER_H + +#define NT_GNU_PROPERTY_TYPE_0 5 +#define GNU_PROPERTY_AARCH64_FEATURE_1_AND 0xc0000000 + +/* Bits for GNU_PROPERTY_AARCH64_FEATURE_1_BTI */ +#define GNU_PROPERTY_AARCH64_FEATURE_1_BTI (1U << 0) +#define GNU_PROPERTY_AARCH64_FEATURE_1_PAC (1U << 1) + + +.macro startfn name:req + .globl \name +\name: + .macro endfn + .size \name, . - \name + .type \name, @function + .purgem endfn + .endm +.endm + +.macro emit_aarch64_feature_1_and + .pushsection .note.gnu.property, "a" + .align 3 + .long 2f - 1f + .long 6f - 3f + .long NT_GNU_PROPERTY_TYPE_0 +1: .string "GNU" +2: + .align 3 +3: .long GNU_PROPERTY_AARCH64_FEATURE_1_AND + .long 5f - 4f +4: +#if BTI + .long GNU_PROPERTY_AARCH64_FEATURE_1_PAC | \ + GNU_PROPERTY_AARCH64_FEATURE_1_BTI +#else + .long 0 +#endif +5: + .align 3 +6: + .popsection +.endm + +.macro paciasp + hint 0x19 +.endm + +.macro autiasp + hint 0x1d +.endm + +.macro __bti_ + hint 0x20 +.endm + +.macro __bti_c + hint 0x22 +.endm + +.macro __bti_j + hint 0x24 +.endm + +.macro __bti_jc + hint 0x26 +.endm + +.macro bti what= + __bti_\what +.endm + +#endif /* ! ASSEMBLER_H */ diff --git a/tools/testing/selftests/arm64/bti/btitest.h b/tools/testing/selftests/arm64/bti/btitest.h new file mode 100644 index 000000000000..2aff9b10336e --- /dev/null +++ b/tools/testing/selftests/arm64/bti/btitest.h @@ -0,0 +1,23 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (C) 2019 Arm Limited + * Original author: Dave Martin <Dave.Martin(a)arm.com> + */ + +#ifndef BTITEST_H +#define BTITEST_H + +/* Trampolines for calling the test stubs: */ +void call_using_br_x0(void (*)(void)); +void call_using_br_x16(void (*)(void)); +void call_using_blr(void (*)(void)); + +/* Test stubs: */ +void nohint_func(void); +void bti_none_func(void); +void bti_c_func(void); +void bti_j_func(void); +void bti_jc_func(void); +void paciasp_func(void); + +#endif /* !BTITEST_H */ diff --git a/tools/testing/selftests/arm64/bti/compiler.h b/tools/testing/selftests/arm64/bti/compiler.h new file mode 100644 index 000000000000..ebb6204f447a --- /dev/null +++ b/tools/testing/selftests/arm64/bti/compiler.h @@ -0,0 +1,21 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (C) 2019 Arm Limited + * Original author: Dave Martin <Dave.Martin(a)arm.com> + */ + +#ifndef COMPILER_H +#define COMPILER_H + +#define __always_unused __attribute__((__unused__)) +#define __noreturn __attribute__((__noreturn__)) +#define __unreachable() __builtin_unreachable() + +/* curse(e) has value e, but the compiler cannot assume so */ +#define curse(e) ({ \ + __typeof__(e) __curse_e = (e); \ + asm ("" : "+r" (__curse_e)); \ + __curse_e; \ +}) + +#endif /* ! COMPILER_H */ diff --git a/tools/testing/selftests/arm64/bti/gen/.gitignore b/tools/testing/selftests/arm64/bti/gen/.gitignore new file mode 100644 index 000000000000..73869fabada4 --- /dev/null +++ b/tools/testing/selftests/arm64/bti/gen/.gitignore @@ -0,0 +1,2 @@ +btitest +nobtitest diff --git a/tools/testing/selftests/arm64/bti/signal.c b/tools/testing/selftests/arm64/bti/signal.c new file mode 100644 index 000000000000..f3fd29b91141 --- /dev/null +++ b/tools/testing/selftests/arm64/bti/signal.c @@ -0,0 +1,37 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2019 Arm Limited + * Original author: Dave Martin <Dave.Martin(a)arm.com> + */ + +#include "system.h" +#include "signal.h" + +int sigemptyset(sigset_t *s) +{ + unsigned int i; + + for (i = 0; i < _NSIG_WORDS; ++i) + s->sig[i] = 0; + + return 0; +} + +int sigaddset(sigset_t *s, int n) +{ + if (n < 1 || n > _NSIG) + return -EINVAL; + + s->sig[(n - 1) / _NSIG_BPW] |= 1UL << (n - 1) % _NSIG_BPW; + return 0; +} + +int sigaction(int n, struct sigaction *sa, const struct sigaction *old) +{ + return syscall(__NR_rt_sigaction, n, sa, old, sizeof(sa->sa_mask)); +} + +int sigprocmask(int how, const sigset_t *mask, sigset_t *old) +{ + return syscall(__NR_rt_sigprocmask, how, mask, old, sizeof(*mask)); +} diff --git a/tools/testing/selftests/arm64/bti/signal.h b/tools/testing/selftests/arm64/bti/signal.h new file mode 100644 index 000000000000..103457dc880e --- /dev/null +++ b/tools/testing/selftests/arm64/bti/signal.h @@ -0,0 +1,21 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (C) 2019 Arm Limited + * Original author: Dave Martin <Dave.Martin(a)arm.com> + */ + +#ifndef SIGNAL_H +#define SIGNAL_H + +#include <linux/signal.h> + +#include "system.h" + +typedef __sighandler_t sighandler_t; + +int sigemptyset(sigset_t *s); +int sigaddset(sigset_t *s, int n); +int sigaction(int n, struct sigaction *sa, const struct sigaction *old); +int sigprocmask(int how, const sigset_t *mask, sigset_t *old); + +#endif /* ! SIGNAL_H */ diff --git a/tools/testing/selftests/arm64/bti/start.S b/tools/testing/selftests/arm64/bti/start.S new file mode 100644 index 000000000000..831f952e0572 --- /dev/null +++ b/tools/testing/selftests/arm64/bti/start.S @@ -0,0 +1,14 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (C) 2019 Arm Limited + * Original author: Dave Martin <Dave.Martin(a)arm.com> + */ + +#include "assembler.h" + +startfn _start + mov x0, sp + b start +endfn + +emit_aarch64_feature_1_and diff --git a/tools/testing/selftests/arm64/bti/syscall.S b/tools/testing/selftests/arm64/bti/syscall.S new file mode 100644 index 000000000000..8dde8b6f3db1 --- /dev/null +++ b/tools/testing/selftests/arm64/bti/syscall.S @@ -0,0 +1,23 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (C) 2019 Arm Limited + * Original author: Dave Martin <Dave.Martin(a)arm.com> + */ + +#include "assembler.h" + +startfn syscall + bti c + mov w8, w0 + mov x0, x1 + mov x1, x2 + mov x2, x3 + mov x3, x4 + mov x4, x5 + mov x5, x6 + mov x6, x7 + svc #0 + ret +endfn + +emit_aarch64_feature_1_and diff --git a/tools/testing/selftests/arm64/bti/system.c b/tools/testing/selftests/arm64/bti/system.c new file mode 100644 index 000000000000..6385d8d4973b --- /dev/null +++ b/tools/testing/selftests/arm64/bti/system.c @@ -0,0 +1,22 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2019 Arm Limited + * Original author: Dave Martin <Dave.Martin(a)arm.com> + */ + +#include "system.h" + +#include <asm/unistd.h> + +#include "compiler.h" + +void __noreturn exit(int n) +{ + syscall(__NR_exit, n); + __unreachable(); +} + +ssize_t write(int fd, const void *buf, size_t size) +{ + return syscall(__NR_write, fd, buf, size); +} diff --git a/tools/testing/selftests/arm64/bti/system.h b/tools/testing/selftests/arm64/bti/system.h new file mode 100644 index 000000000000..aca118589705 --- /dev/null +++ b/tools/testing/selftests/arm64/bti/system.h @@ -0,0 +1,28 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (C) 2019 Arm Limited + * Original author: Dave Martin <Dave.Martin(a)arm.com> + */ + +#ifndef SYSTEM_H +#define SYSTEM_H + +#include <linux/types.h> +#include <linux/stddef.h> + +typedef __kernel_size_t size_t; +typedef __kernel_ssize_t ssize_t; + +#include <linux/errno.h> +#include <asm/hwcap.h> +#include <asm/ptrace.h> +#include <asm/unistd.h> + +#include "compiler.h" + +long syscall(int nr, ...); + +void __noreturn exit(int n); +ssize_t write(int fd, const void *buf, size_t size); + +#endif /* ! SYSTEM_H */ diff --git a/tools/testing/selftests/arm64/bti/test.c b/tools/testing/selftests/arm64/bti/test.c new file mode 100644 index 000000000000..656b04976ccc --- /dev/null +++ b/tools/testing/selftests/arm64/bti/test.c @@ -0,0 +1,234 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2019,2021 Arm Limited + * Original author: Dave Martin <Dave.Martin(a)arm.com> + */ + +#include "system.h" + +#include <linux/errno.h> +#include <linux/auxvec.h> +#include <linux/signal.h> +#include <asm/sigcontext.h> +#include <asm/ucontext.h> + +typedef struct ucontext ucontext_t; + +#include "btitest.h" +#include "compiler.h" +#include "signal.h" + +#define EXPECTED_TESTS 18 + +static volatile unsigned int test_num = 1; +static unsigned int test_passed; +static unsigned int test_failed; +static unsigned int test_skipped; + +static void fdputs(int fd, const char *str) +{ + size_t len = 0; + const char *p = str; + + while (*p++) + ++len; + + write(fd, str, len); +} + +static void putstr(const char *str) +{ + fdputs(1, str); +} + +static void putnum(unsigned int num) +{ + char c; + + if (num / 10) + putnum(num / 10); + + c = '0' + (num % 10); + write(1, &c, 1); +} + +#define puttestname(test_name, trampoline_name) do { \ + putstr(test_name); \ + putstr("/"); \ + putstr(trampoline_name); \ +} while (0) + +void print_summary(void) +{ + putstr("# Totals: pass:"); + putnum(test_passed); + putstr(" fail:"); + putnum(test_failed); + putstr(" xfail:0 xpass:0 skip:"); + putnum(test_skipped); + putstr(" error:0\n"); +} + +static const char *volatile current_test_name; +static const char *volatile current_trampoline_name; +static volatile int sigill_expected, sigill_received; + +static void handler(int n, siginfo_t *si __always_unused, + void *uc_ __always_unused) +{ + ucontext_t *uc = uc_; + + putstr("# \t[SIGILL in "); + puttestname(current_test_name, current_trampoline_name); + putstr(", BTYPE="); + write(1, &"00011011"[((uc->uc_mcontext.pstate & PSR_BTYPE_MASK) + >> PSR_BTYPE_SHIFT) * 2], 2); + if (!sigill_expected) { + putstr("]\n"); + putstr("not ok "); + putnum(test_num); + putstr(" "); + puttestname(current_test_name, current_trampoline_name); + putstr("(unexpected SIGILL)\n"); + print_summary(); + exit(128 + n); + } + + putstr(" (expected)]\n"); + sigill_received = 1; + /* zap BTYPE so that resuming the faulting code will work */ + uc->uc_mcontext.pstate &= ~PSR_BTYPE_MASK; +} + +static int skip_all; + +static void __do_test(void (*trampoline)(void (*)(void)), + void (*fn)(void), + const char *trampoline_name, + const char *name, + int expect_sigill) +{ + if (skip_all) { + test_skipped++; + putstr("ok "); + putnum(test_num); + putstr(" "); + puttestname(name, trampoline_name); + putstr(" # SKIP\n"); + + return; + } + + /* Branch Target exceptions should only happen in BTI binaries: */ + if (!BTI) + expect_sigill = 0; + + sigill_expected = expect_sigill; + sigill_received = 0; + current_test_name = name; + current_trampoline_name = trampoline_name; + + trampoline(fn); + + if (expect_sigill && !sigill_received) { + putstr("not ok "); + test_failed++; + } else { + putstr("ok "); + test_passed++; + } + putnum(test_num++); + putstr(" "); + puttestname(name, trampoline_name); + putstr("\n"); +} + +#define do_test(expect_sigill_br_x0, \ + expect_sigill_br_x16, \ + expect_sigill_blr, \ + name) \ +do { \ + __do_test(call_using_br_x0, name, "call_using_br_x0", #name, \ + expect_sigill_br_x0); \ + __do_test(call_using_br_x16, name, "call_using_br_x16", #name, \ + expect_sigill_br_x16); \ + __do_test(call_using_blr, name, "call_using_blr", #name, \ + expect_sigill_blr); \ +} while (0) + +void start(int *argcp) +{ + struct sigaction sa; + void *const *p; + const struct auxv_entry { + unsigned long type; + unsigned long val; + } *auxv; + unsigned long hwcap = 0, hwcap2 = 0; + + putstr("TAP version 13\n"); + putstr("1.."); + putnum(EXPECTED_TESTS); + putstr("\n"); + + /* Gross hack for finding AT_HWCAP2 from the initial process stack: */ + p = (void *const *)argcp + 1 + *argcp + 1; /* start of environment */ + /* step over environment */ + while (*p++) + ; + for (auxv = (const struct auxv_entry *)p; auxv->type != AT_NULL; ++auxv) { + switch (auxv->type) { + case AT_HWCAP: + hwcap = auxv->val; + break; + case AT_HWCAP2: + hwcap2 = auxv->val; + break; + default: + break; + } + } + + if (hwcap & HWCAP_PACA) + putstr("# HWCAP_PACA present\n"); + else + putstr("# HWCAP_PACA not present\n"); + + if (hwcap2 & HWCAP2_BTI) { + putstr("# HWCAP2_BTI present\n"); + if (!(hwcap & HWCAP_PACA)) + putstr("# Bad hardware? Expect problems.\n"); + } else { + putstr("# HWCAP2_BTI not present\n"); + skip_all = 1; + } + + putstr("# Test binary"); + if (!BTI) + putstr(" not"); + putstr(" built for BTI\n"); + + sa.sa_handler = (sighandler_t)(void *)handler; + sa.sa_flags = SA_SIGINFO; + sigemptyset(&sa.sa_mask); + sigaction(SIGILL, &sa, NULL); + sigaddset(&sa.sa_mask, SIGILL); + sigprocmask(SIG_UNBLOCK, &sa.sa_mask, NULL); + + do_test(1, 1, 1, nohint_func); + do_test(1, 1, 1, bti_none_func); + do_test(1, 0, 0, bti_c_func); + do_test(0, 0, 1, bti_j_func); + do_test(0, 0, 0, bti_jc_func); + do_test(1, 0, 0, paciasp_func); + + print_summary(); + + if (test_num - 1 != EXPECTED_TESTS) + putstr("# WARNING - EXPECTED TEST COUNT WRONG\n"); + + if (test_failed) + exit(1); + else + exit(0); +} diff --git a/tools/testing/selftests/arm64/bti/teststubs.S b/tools/testing/selftests/arm64/bti/teststubs.S new file mode 100644 index 000000000000..b62c8c35f67e --- /dev/null +++ b/tools/testing/selftests/arm64/bti/teststubs.S @@ -0,0 +1,39 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (C) 2019 Arm Limited + * Original author: Dave Martin <Dave.Martin(a)arm.com> + */ + +#include "assembler.h" + +startfn bti_none_func + bti + ret +endfn + +startfn bti_c_func + bti c + ret +endfn + +startfn bti_j_func + bti j + ret +endfn + +startfn bti_jc_func + bti jc + ret +endfn + +startfn paciasp_func + paciasp + autiasp + ret +endfn + +startfn nohint_func + ret +endfn + +emit_aarch64_feature_1_and diff --git a/tools/testing/selftests/arm64/bti/trampoline.S b/tools/testing/selftests/arm64/bti/trampoline.S new file mode 100644 index 000000000000..09beb3f361f1 --- /dev/null +++ b/tools/testing/selftests/arm64/bti/trampoline.S @@ -0,0 +1,29 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (C) 2019 Arm Limited + * Original author: Dave Martin <Dave.Martin(a)arm.com> + */ + +#include "assembler.h" + +startfn call_using_br_x0 + bti c + br x0 +endfn + +startfn call_using_br_x16 + bti c + mov x16, x0 + br x16 +endfn + +startfn call_using_blr + paciasp + stp x29, x30, [sp, #-16]! + blr x0 + ldp x29, x30, [sp], #16 + autiasp + ret +endfn + +emit_aarch64_feature_1_and -- 2.20.1

4 years, 3 months

2
1
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[PATCH 00/11] kselftest/arm64: mte: Fix feature detection and compilation

by Andre Przywara

When trying to run the arm64 MTE (Memory Tagging Extension) selftests on a model with the new FEAT_MTE3 capability, the MTE feature detection failed, because it was overzealously checking for one exact feature version only (0b0010). Trying to fix that (patch 06/11) led me into the rabbit hole of userland tool compilation, which triggered patches 01-05/11, to let me actually compile the selftests on an arm64 machine running Ubuntu 20.04. Before I actually fixed that, I tried some other compiler and distro; patches 07 and 08 are my witnesses. Then I got brave and tried clang: entering patches 09/11 and 10/11. Eventually I tried to run the whole thing on that model again, and, you guessed it, patch 11/11 concludes this apparent "2 minute job". Eventually I can now compile the mte selftests on Ubuntu 20.04 with both the native gcc and clang without warnings, also with some custom made cross compiler. And they even run now! Please have a look, also you may try to compile it on your setup, if you feel adventurous: $ make -C tools/testing/selftests TARGETS=arm64 ARM64_SUBTARGETS=mte Cheers, Andre Andre Przywara (11): kselftest/arm64: mte: Fix compilation with native compiler kselftest/arm64: mte: Fix pthread linking kselftest/arm64: mte: ksm_options: Fix fscanf warning kselftest/arm64: mte: user_mem: Fix write() warning kselftest/arm64: mte: common: Fix write() warnings kselftest/arm64: mte: Fix MTE feature detection kselftest/arm64: mte: Use cross-compiler if specified kselftest/arm64: mte: Output warning about failing compiler kselftest/arm64: mte: Makefile: Fix clang compilation kselftest/arm64: mte: Fix clang warning kselftest/arm64: mte: Report filename on failing temp file creation tools/testing/selftests/arm64/mte/Makefile | 15 +++++-- .../selftests/arm64/mte/check_ksm_options.c | 5 ++- .../selftests/arm64/mte/check_user_mem.c | 3 +- .../selftests/arm64/mte/mte_common_util.c | 39 +++++++++++-------- 4 files changed, 39 insertions(+), 23 deletions(-) -- 2.17.5

4 years, 3 months

4
15
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[GIT PULL] KUnit fixes update for Linux 5.12-rc5

by Shuah Khan

Hi Linus, Please pull the following KUnit fixes update for Linux 5.12-rc5. This KUnit update for Linux 5.12-rc5 consists of two fixes to kunit tool from David Gow. diff is attached. thanks, -- Shuah ---------------------------------------------------------------- The following changes since commit a38fd8748464831584a19438cbb3082b5a2dab15: Linux 5.12-rc2 (2021-03-05 17:33:41 -0800) are available in the Git repository at: git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest tags/linux-kselftest-kunit-fixes-5.12-rc5.1 for you to fetch changes up to 7fd53f41f771d250eb08db08650940f017e37c26: kunit: tool: Disable PAGE_POISONING under --alltests (2021-03-11 14:37:37 -0700) ---------------------------------------------------------------- linux-kselftest-kunit-fixes-5.12-rc5.1 This KUnit update for Linux 5.12-rc5 consists of two fixes to kunit tool from David Gow. ---------------------------------------------------------------- David Gow (2): kunit: tool: Fix a python tuple typing error kunit: tool: Disable PAGE_POISONING under --alltests tools/testing/kunit/configs/broken_on_uml.config | 2 ++ tools/testing/kunit/kunit_config.py | 2 +- 2 files changed, 3 insertions(+), 1 deletion(-) ----------------------------------------------------------------

4 years, 3 months

2
1
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[PATCH] tools: testing: Remove duplicate include of sched.h

by Wan Jiabing

sched.h has been included at line 33. So we remove the duplicate one at line 36. Signed-off-by: Wan Jiabing <wanjiabing(a)vivo.com> --- tools/testing/selftests/powerpc/mm/tlbie_test.c | 1 - 1 file changed, 1 deletion(-) diff --git a/tools/testing/selftests/powerpc/mm/tlbie_test.c b/tools/testing/selftests/powerpc/mm/tlbie_test.c index f85a0938ab25..48344a74b212 100644 --- a/tools/testing/selftests/powerpc/mm/tlbie_test.c +++ b/tools/testing/selftests/powerpc/mm/tlbie_test.c @@ -33,7 +33,6 @@ #include <sched.h> #include <time.h> #include <stdarg.h> -#include <sched.h> #include <pthread.h> #include <signal.h> #include <sys/prctl.h> -- 2.25.1

4 years, 3 months

2
1
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[PATCH] tools: testing: inttypes.h is included twice

by Wan Jiabing

inttypes.h has been included at line 19. So we remove the duplicate one at line 23. Signed-off-by: Wan Jiabing <wanjiabing(a)vivo.com> --- tools/testing/selftests/powerpc/tm/tm-poison.c | 1 - 1 file changed, 1 deletion(-) diff --git a/tools/testing/selftests/powerpc/tm/tm-poison.c b/tools/testing/selftests/powerpc/tm/tm-poison.c index 29e5f26af7b9..27c083a03d1f 100644 --- a/tools/testing/selftests/powerpc/tm/tm-poison.c +++ b/tools/testing/selftests/powerpc/tm/tm-poison.c @@ -20,7 +20,6 @@ #include <sched.h> #include <sys/types.h> #include <signal.h> -#include <inttypes.h> #include "tm.h" -- 2.25.1

4 years, 3 months

1
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[PATCH] tools: testing: pthread.h is included twice

by Wan Jiabing

pthread.h has been included at line 17. So we remove the duplicate one at line 20. Signed-off-by: Wan Jiabing <wanjiabing(a)vivo.com> --- tools/testing/selftests/powerpc/tm/tm-vmx-unavail.c | 1 - 1 file changed, 1 deletion(-) diff --git a/tools/testing/selftests/powerpc/tm/tm-vmx-unavail.c b/tools/testing/selftests/powerpc/tm/tm-vmx-unavail.c index e2a0c07e8362..9ef37a9836ac 100644 --- a/tools/testing/selftests/powerpc/tm/tm-vmx-unavail.c +++ b/tools/testing/selftests/powerpc/tm/tm-vmx-unavail.c @@ -17,7 +17,6 @@ #include <pthread.h> #include <sys/mman.h> #include <unistd.h> -#include <pthread.h> #include "tm.h" #include "utils.h" -- 2.25.1

4 years, 3 months

1
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[PATCH bpf-next v2 0/2] add support for batched ops in LPM trie

by Pedro Tammela

The patch itself is straightforward thanks to the infrastructure that is already in-place. The tests follows the other '*_map_batch_ops' tests with minor tweaks. v1 -> v2: Fixes for checkpatch warnings Pedro Tammela (2): bpf: add support for batched operations in LPM trie maps bpf: selftests: add tests for batched ops in LPM trie maps kernel/bpf/lpm_trie.c | 3 + .../map_tests/lpm_trie_map_batch_ops.c (new) | 158 ++++++++++++++++++ 2 files changed, 161 insertions(+) create mode 100644 tools/testing/selftests/bpf/map_tests/lpm_trie_map_batch_ops.c -- 2.25.1

4 years, 3 months

1
2
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Re: [selftests] e48d82b67a: BUG_TestSlub_RZ_alloc(Not_tainted):Redzone_overwritten

by Vlastimil Babka

On 3/17/21 9:36 AM, kernel test robot wrote: > > > Greeting, > > FYI, we noticed the following commit (built with gcc-9): > > commit: e48d82b67a2b760eedf7b95ca15f41267496386c ("[PATCH 1/2] selftests: add a kselftest for SLUB debugging functionality") > url: https://github.com/0day-ci/linux/commits/glittao-gmail-com/selftests-add-a-… > base: https://git.kernel.org/cgit/linux/kernel/git/shuah/linux-kselftest.git next > > in testcase: trinity > version: trinity-static-i386-x86_64-f93256fb_2019-08-28 > with following parameters: > > group: group-04 > > test-description: Trinity is a linux system call fuzz tester. > test-url: http://codemonkey.org.uk/projects/trinity/ > > > on test machine: qemu-system-i386 -enable-kvm -cpu SandyBridge -smp 2 -m 8G > > caused below changes (please refer to attached dmesg/kmsg for entire log/backtrace): > > > +---------------------------------------------------------------------------------------------------------------+-----------+------------+ > | | v5.12-rc2 | e48d82b67a | > +---------------------------------------------------------------------------------------------------------------+-----------+------------+ > | BUG_TestSlub_RZ_alloc(Not_tainted):Redzone_overwritten | 0 | 69 | > | INFO:0x(ptrval)-0x(ptrval)@offset=#.First_byte#instead_of | 0 | 69 | > | INFO:Allocated_in_resiliency_test_age=#cpu=#pid= | 0 | 69 | > | INFO:Slab0x(ptrval)objects=#used=#fp=0x(ptrval)flags= | 0 | 69 | > | INFO:Object0x(ptrval)@offset=#fp=0x(ptrval) | 0 | 69 | > | BUG_TestSlub_next_ptr_free(Tainted:G_B):Freechain_corrupt | 0 | 69 | > | INFO:Freed_in_resiliency_test_age=#cpu=#pid= | 0 | 69 | > | BUG_TestSlub_next_ptr_free(Tainted:G_B):Wrong_object_count.Counter_is#but_counted_were | 0 | 69 | > | BUG_TestSlub_next_ptr_free(Tainted:G_B):Redzone_overwritten | 0 | 69 | > | BUG_TestSlub_next_ptr_free(Tainted:G_B):Objects_remaining_in_TestSlub_next_ptr_free_on__kmem_cache_shutdown() | 0 | 69 | > | INFO:Object0x(ptrval)@offset= | 0 | 69 | > | BUG_TestSlub_1th_word_free(Tainted:G_B):Poison_overwritten | 0 | 69 | > | BUG_TestSlub_50th_word_free(Tainted:G_B):Poison_overwritten | 0 | 69 | > | BUG_TestSlub_RZ_free(Tainted:G_B):Redzone_overwritten | 0 | 69 | > +---------------------------------------------------------------------------------------------------------------+-----------+------------+ > > > If you fix the issue, kindly add following tag > Reported-by: kernel test robot <oliver.sang(a)intel.com> > > > > [ 22.154049] random: get_random_u32 called from __kmem_cache_create+0x23/0x3e0 with crng_init=0 > [ 22.154070] random: get_random_u32 called from cache_random_seq_create+0x7c/0x140 with crng_init=0 > [ 22.154167] random: get_random_u32 called from allocate_slab+0x155/0x5e0 with crng_init=0 > [ 22.154690] test_slub: 1. kmem_cache: Clobber Redzone 0x12->0x(ptrval) > [ 22.164499] ============================================================================= > [ 22.166629] BUG TestSlub_RZ_alloc (Not tainted): Redzone overwritten > [ 22.168179] ----------------------------------------------------------------------------- > [ 22.168179] > [ 22.168372] Disabling lock debugging due to kernel taint > [ 22.168372] INFO: 0x(ptrval)-0x(ptrval) @offset=1064. First byte 0x12 instead of 0xcc > [ 22.168372] INFO: Allocated in resiliency_test+0x47/0x1be age=3 cpu=0 pid=1 > [ 22.168372] __slab_alloc+0x57/0x80 > [ 22.168372] kmem_cache_alloc (kbuild/src/consumer/mm/slub.c:2871 kbuild/src/consumer/mm/slub.c:2915 kbuild/src/consumer/mm/slub.c:2920) > [ 22.168372] resiliency_test (kbuild/src/consumer/lib/test_slub.c:34 kbuild/src/consumer/lib/test_slub.c:107) > [ 22.168372] test_slub_init (kbuild/src/consumer/lib/test_slub.c:124) > [ 22.168372] do_one_initcall (kbuild/src/consumer/init/main.c:1226) > [ 22.168372] kernel_init_freeable (kbuild/src/consumer/init/main.c:1298 kbuild/src/consumer/init/main.c:1315 kbuild/src/consumer/init/main.c:1335 kbuild/src/consumer/init/main.c:1537) > [ 22.168372] kernel_init (kbuild/src/consumer/init/main.c:1426) > [ 22.168372] ret_from_fork (kbuild/src/consumer/arch/x86/entry/entry_32.S:856) > [ 22.168372] INFO: Slab 0x(ptrval) objects=16 used=1 fp=0x(ptrval) flags=0x40000201 > [ 22.168372] INFO: Object 0x(ptrval) @offset=1000 fp=0x(ptrval) > [ 22.168372] > [ 22.168372] Redzone (ptrval): cc cc cc cc cc cc cc cc ........ > [ 22.168372] Object (ptrval): 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk > [ 22.168372] Object (ptrval): 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b a5 kkkkkkkkkkkkkkk. > [ 22.168372] Redzone (ptrval): 12 cc cc cc .... > [ 22.168372] Padding (ptrval): 5a 5a 5a 5a 5a 5a 5a 5a ZZZZZZZZ > [ 22.168372] CPU: 0 PID: 1 Comm: swapper/0 Tainted: G B 5.12.0-rc2-00001-ge48d82b67a2b #1 > [ 22.168372] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014 > [ 22.168372] Call Trace: > [ 22.168372] dump_stack (kbuild/src/consumer/lib/dump_stack.c:122) > [ 22.168372] print_trailer (kbuild/src/consumer/mm/slub.c:737) > [ 22.168372] check_bytes_and_report.cold (kbuild/src/consumer/mm/slub.c:807) > [ 22.168372] check_object (kbuild/src/consumer/mm/slub.c:914) > [ 22.168372] validate_slab (kbuild/src/consumer/mm/slub.c:4635) Hm but in this case the output means the tested functionality (slub debugging) is working as intended. So what can we do? Indicate/teach somehow to the bot that this is OK? Does kselftest have some support for this? Or silence the validation output for testing purposes? (I would prefer not to) Thanks, Vlastimil

4 years, 3 months

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3
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[PATCH v5 1/2] mm: huge_memory: a new debugfs interface for splitting THP tests.

by Zi Yan

From: Zi Yan <ziy(a)nvidia.com> We did not have a direct user interface of splitting the compound page backing a THP and there is no need unless we want to expose the THP implementation details to users. Make <debugfs>/split_huge_pages accept a new command to do that. By writing "<pid>,<vaddr_start>,<vaddr_end>" to <debugfs>/split_huge_pages, THPs within the given virtual address range from the process with the given pid are split. It is used to test split_huge_page function. In addition, a selftest program is added to tools/testing/selftests/vm to utilize the interface by splitting PMD THPs and PTE-mapped THPs. This does not change the old behavior, i.e., writing 1 to the interface to split all THPs in the system. Changelog: >From v5: 1. Skipped special VMAs and other fixes. (suggested by Yang Shi) >From v4: 1. Fixed the error code return issue, spotted by kernel test robot <lkp(a)intel.com>. >From v3: 1. Factored out split huge pages in the given pid code to a separate function. 2. Added the missing put_page for not split pages. 3. pr_debug -> pr_info, make reading results simpler. >From v2: 1. Reused existing <debugfs>/split_huge_pages interface. (suggested by Yang Shi) >From v1: 1. Removed unnecessary calling to vma_migratable, spotted by kernel test robot <lkp(a)intel.com>. 2. Dropped the use of find_mm_struct and code it directly, since there is no need for the permission check in that function and the function is only available when migration is on. 3. Added some comments in the selftest program to clarify how PTE-mapped THPs are formed. Signed-off-by: Zi Yan <ziy(a)nvidia.com> --- mm/huge_memory.c | 143 +++++++- tools/testing/selftests/vm/.gitignore | 1 + tools/testing/selftests/vm/Makefile | 1 + .../selftests/vm/split_huge_page_test.c | 318 ++++++++++++++++++ 4 files changed, 456 insertions(+), 7 deletions(-) create mode 100644 tools/testing/selftests/vm/split_huge_page_test.c diff --git a/mm/huge_memory.c b/mm/huge_memory.c index bff92dea5ab3..9bf9bc489228 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -7,6 +7,7 @@ #include <linux/mm.h> #include <linux/sched.h> +#include <linux/sched/mm.h> #include <linux/sched/coredump.h> #include <linux/sched/numa_balancing.h> #include <linux/highmem.h> @@ -2922,16 +2923,14 @@ static struct shrinker deferred_split_shrinker = { }; #ifdef CONFIG_DEBUG_FS -static int split_huge_pages_set(void *data, u64 val) +static void split_huge_pages_all(void) { struct zone *zone; struct page *page; unsigned long pfn, max_zone_pfn; unsigned long total = 0, split = 0; - if (val != 1) - return -EINVAL; - + pr_info("Split all THPs\n"); for_each_populated_zone(zone) { max_zone_pfn = zone_end_pfn(zone); for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++) { @@ -2959,11 +2958,141 @@ static int split_huge_pages_set(void *data, u64 val) } pr_info("%lu of %lu THP split\n", split, total); +} - return 0; +static int split_huge_pages_pid(int pid, unsigned long vaddr_start, + unsigned long vaddr_end) +{ + int ret = 0; + struct task_struct *task; + struct mm_struct *mm; + unsigned long total = 0, split = 0; + unsigned long addr; + + vaddr_start &= PAGE_MASK; + vaddr_end &= PAGE_MASK; + + /* Find the task_struct from pid */ + rcu_read_lock(); + task = find_task_by_vpid(pid); + if (!task) { + rcu_read_unlock(); + ret = -ESRCH; + goto out; + } + get_task_struct(task); + rcu_read_unlock(); + + /* Find the mm_struct */ + mm = get_task_mm(task); + put_task_struct(task); + + if (!mm) { + ret = -EINVAL; + goto out; + } + + pr_info("Split huge pages in pid: %d, vaddr: [0x%lx - 0x%lx]\n", + pid, vaddr_start, vaddr_end); + + mmap_read_lock(mm); + /* + * always increase addr by PAGE_SIZE, since we could have a PTE page + * table filled with PTE-mapped THPs, each of which is distinct. + */ + for (addr = vaddr_start; addr < vaddr_end; addr += PAGE_SIZE) { + struct vm_area_struct *vma = find_vma(mm, addr); + unsigned int follflags; + struct page *page; + + if (!vma || addr < vma->vm_start) + break; + + /* skip special VMA and hugetlb VMA */ + if (vma_is_special_huge(vma) || is_vm_hugetlb_page(vma)) { + addr = vma->vm_end; + continue; + } + + /* FOLL_DUMP to ignore special (like zero) pages */ + follflags = FOLL_GET | FOLL_DUMP; + page = follow_page(vma, addr, follflags); + + if (IS_ERR(page)) + continue; + if (!page) + continue; + + if (!is_transparent_hugepage(page)) + goto next; + + total++; + if (!can_split_huge_page(compound_head(page), NULL)) + goto next; + + if (!trylock_page(page)) + goto next; + + if (!split_huge_page(page)) + split++; + + unlock_page(page); +next: + put_page(page); + } + mmap_read_unlock(mm); + mmput(mm); + + pr_info("%lu of %lu THP split\n", split, total); + +out: + return ret; } -DEFINE_DEBUGFS_ATTRIBUTE(split_huge_pages_fops, NULL, split_huge_pages_set, - "%llu\n"); + +static ssize_t split_huge_pages_write(struct file *file, const char __user *buf, + size_t count, loff_t *ppops) +{ + static DEFINE_MUTEX(split_debug_mutex); + ssize_t ret; + char input_buf[80]; /* hold pid, start_vaddr, end_vaddr */ + int pid; + unsigned long vaddr_start, vaddr_end; + + ret = mutex_lock_interruptible(&split_debug_mutex); + if (ret) + return ret; + + ret = -EFAULT; + + memset(input_buf, 0, 80); + if (copy_from_user(input_buf, buf, min_t(size_t, count, 80))) + goto out; + + input_buf[79] = '\0'; + ret = sscanf(input_buf, "%d,0x%lx,0x%lx", &pid, &vaddr_start, &vaddr_end); + if (ret == 1 && pid == 1) { + split_huge_pages_all(); + ret = strlen(input_buf); + goto out; + } else if (ret != 3) { + ret = -EINVAL; + goto out; + } + + ret = split_huge_pages_pid(pid, vaddr_start, vaddr_end); + if (!ret) + ret = strlen(input_buf); +out: + mutex_unlock(&split_debug_mutex); + return ret; + +} + +static const struct file_operations split_huge_pages_fops = { + .owner = THIS_MODULE, + .write = split_huge_pages_write, + .llseek = no_llseek, +}; static int __init split_huge_pages_debugfs(void) { diff --git a/tools/testing/selftests/vm/.gitignore b/tools/testing/selftests/vm/.gitignore index 9a35c3f6a557..1f651e85ed60 100644 --- a/tools/testing/selftests/vm/.gitignore +++ b/tools/testing/selftests/vm/.gitignore @@ -22,3 +22,4 @@ map_fixed_noreplace write_to_hugetlbfs hmm-tests local_config.* +split_huge_page_test diff --git a/tools/testing/selftests/vm/Makefile b/tools/testing/selftests/vm/Makefile index d42115e4284d..4cbc91d6869f 100644 --- a/tools/testing/selftests/vm/Makefile +++ b/tools/testing/selftests/vm/Makefile @@ -42,6 +42,7 @@ TEST_GEN_FILES += on-fault-limit TEST_GEN_FILES += thuge-gen TEST_GEN_FILES += transhuge-stress TEST_GEN_FILES += userfaultfd +TEST_GEN_FILES += split_huge_page_test ifeq ($(MACHINE),x86_64) CAN_BUILD_I386 := $(shell ./../x86/check_cc.sh $(CC) ../x86/trivial_32bit_program.c -m32) diff --git a/tools/testing/selftests/vm/split_huge_page_test.c b/tools/testing/selftests/vm/split_huge_page_test.c new file mode 100644 index 000000000000..2c0c18e60c57 --- /dev/null +++ b/tools/testing/selftests/vm/split_huge_page_test.c @@ -0,0 +1,318 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * A test of splitting PMD THPs and PTE-mapped THPs from a specified virtual + * address range in a process via <debugfs>/split_huge_pages interface. + */ + +#define _GNU_SOURCE +#include <stdio.h> +#include <stdlib.h> +#include <unistd.h> +#include <inttypes.h> +#include <string.h> +#include <fcntl.h> +#include <sys/mman.h> +#include <malloc.h> +#include <stdbool.h> + +uint64_t pagesize; +unsigned int pageshift; +uint64_t pmd_pagesize; + +#define PMD_SIZE_PATH "/sys/kernel/mm/transparent_hugepage/hpage_pmd_size" +#define SPLIT_DEBUGFS "/sys/kernel/debug/split_huge_pages" +#define SMAP_PATH "/proc/self/smaps" +#define INPUT_MAX 80 + +#define PFN_MASK ((1UL<<55)-1) +#define KPF_THP (1UL<<22) + +int is_backed_by_thp(char *vaddr, int pagemap_file, int kpageflags_file) +{ + uint64_t paddr; + uint64_t page_flags; + + if (pagemap_file) { + pread(pagemap_file, &paddr, sizeof(paddr), + ((long)vaddr >> pageshift) * sizeof(paddr)); + + if (kpageflags_file) { + pread(kpageflags_file, &page_flags, sizeof(page_flags), + (paddr & PFN_MASK) * sizeof(page_flags)); + + return !!(page_flags & KPF_THP); + } + } + return 0; +} + + +static uint64_t read_pmd_pagesize(void) +{ + int fd; + char buf[20]; + ssize_t num_read; + + fd = open(PMD_SIZE_PATH, O_RDONLY); + if (fd == -1) { + perror("Open hpage_pmd_size failed"); + exit(EXIT_FAILURE); + } + num_read = read(fd, buf, 19); + if (num_read < 1) { + close(fd); + perror("Read hpage_pmd_size failed"); + exit(EXIT_FAILURE); + } + buf[num_read] = '\0'; + close(fd); + + return strtoul(buf, NULL, 10); +} + +static int write_file(const char *path, const char *buf, size_t buflen) +{ + int fd; + ssize_t numwritten; + + fd = open(path, O_WRONLY); + if (fd == -1) + return 0; + + numwritten = write(fd, buf, buflen - 1); + close(fd); + if (numwritten < 1) + return 0; + + return (unsigned int) numwritten; +} + +static void write_debugfs(int pid, uint64_t vaddr_start, uint64_t vaddr_end) +{ + char input[INPUT_MAX]; + int ret; + + ret = snprintf(input, INPUT_MAX, "%d,0x%lx,0x%lx", pid, vaddr_start, + vaddr_end); + if (ret >= INPUT_MAX) { + printf("%s: Debugfs input is too long\n", __func__); + exit(EXIT_FAILURE); + } + + if (!write_file(SPLIT_DEBUGFS, input, ret + 1)) { + perror(SPLIT_DEBUGFS); + exit(EXIT_FAILURE); + } +} + +#define MAX_LINE_LENGTH 500 + +static bool check_for_pattern(FILE *fp, const char *pattern, char *buf) +{ + while (fgets(buf, MAX_LINE_LENGTH, fp) != NULL) { + if (!strncmp(buf, pattern, strlen(pattern))) + return true; + } + return false; +} + +static uint64_t check_huge(void *addr) +{ + uint64_t thp = 0; + int ret; + FILE *fp; + char buffer[MAX_LINE_LENGTH]; + char addr_pattern[MAX_LINE_LENGTH]; + + ret = snprintf(addr_pattern, MAX_LINE_LENGTH, "%08lx-", + (unsigned long) addr); + if (ret >= MAX_LINE_LENGTH) { + printf("%s: Pattern is too long\n", __func__); + exit(EXIT_FAILURE); + } + + + fp = fopen(SMAP_PATH, "r"); + if (!fp) { + printf("%s: Failed to open file %s\n", __func__, SMAP_PATH); + exit(EXIT_FAILURE); + } + if (!check_for_pattern(fp, addr_pattern, buffer)) + goto err_out; + + /* + * Fetch the AnonHugePages: in the same block and check the number of + * hugepages. + */ + if (!check_for_pattern(fp, "AnonHugePages:", buffer)) + goto err_out; + + if (sscanf(buffer, "AnonHugePages:%10ld kB", &thp) != 1) { + printf("Reading smap error\n"); + exit(EXIT_FAILURE); + } + +err_out: + fclose(fp); + return thp; +} + +void split_pmd_thp(void) +{ + char *one_page; + size_t len = 4 * pmd_pagesize; + uint64_t thp_size; + size_t i; + + one_page = memalign(pmd_pagesize, len); + + if (!one_page) { + printf("Fail to allocate memory\n"); + exit(EXIT_FAILURE); + } + + madvise(one_page, len, MADV_HUGEPAGE); + + for (i = 0; i < len; i++) + one_page[i] = (char)i; + + thp_size = check_huge(one_page); + if (!thp_size) { + printf("No THP is allocated\n"); + exit(EXIT_FAILURE); + } + + /* split all THPs */ + write_debugfs(getpid(), (uint64_t)one_page, (uint64_t)one_page + len); + + for (i = 0; i < len; i++) + if (one_page[i] != (char)i) { + printf("%ld byte corrupted\n", i); + exit(EXIT_FAILURE); + } + + + thp_size = check_huge(one_page); + if (thp_size) { + printf("Still %ld kB AnonHugePages not split\n", thp_size); + exit(EXIT_FAILURE); + } + + printf("Split huge pages successful\n"); + free(one_page); +} + +void split_pte_mapped_thp(void) +{ + char *one_page, *pte_mapped, *pte_mapped2; + size_t len = 4 * pmd_pagesize; + uint64_t thp_size; + size_t i; + const char *pagemap_template = "/proc/%d/pagemap"; + const char *kpageflags_proc = "/proc/kpageflags"; + char pagemap_proc[255]; + int pagemap_fd; + int kpageflags_fd; + + if (snprintf(pagemap_proc, 255, pagemap_template, getpid()) < 0) { + perror("get pagemap proc error"); + exit(EXIT_FAILURE); + } + pagemap_fd = open(pagemap_proc, O_RDONLY); + + if (pagemap_fd == -1) { + perror("read pagemap:"); + exit(EXIT_FAILURE); + } + + kpageflags_fd = open(kpageflags_proc, O_RDONLY); + + if (kpageflags_fd == -1) { + perror("read kpageflags:"); + exit(EXIT_FAILURE); + } + + one_page = mmap((void *)(1UL << 30), len, PROT_READ | PROT_WRITE, + MAP_ANONYMOUS | MAP_PRIVATE, -1, 0); + + madvise(one_page, len, MADV_HUGEPAGE); + + for (i = 0; i < len; i++) + one_page[i] = (char)i; + + thp_size = check_huge(one_page); + if (!thp_size) { + printf("No THP is allocated\n"); + exit(EXIT_FAILURE); + } + + /* remap the first pagesize of first THP */ + pte_mapped = mremap(one_page, pagesize, pagesize, MREMAP_MAYMOVE); + + /* remap the Nth pagesize of Nth THP */ + for (i = 1; i < 4; i++) { + pte_mapped2 = mremap(one_page + pmd_pagesize * i + pagesize * i, + pagesize, pagesize, + MREMAP_MAYMOVE|MREMAP_FIXED, + pte_mapped + pagesize * i); + if (pte_mapped2 == (char *)-1) { + perror("mremap failed"); + exit(EXIT_FAILURE); + } + } + + /* smap does not show THPs after mremap, use kpageflags instead */ + thp_size = 0; + for (i = 0; i < pagesize * 4; i++) + if (i % pagesize == 0 && + is_backed_by_thp(&pte_mapped[i], pagemap_fd, kpageflags_fd)) + thp_size++; + + if (thp_size != 4) { + printf("Some THPs are missing during mremap\n"); + exit(EXIT_FAILURE); + } + + /* split all remapped THPs */ + write_debugfs(getpid(), (uint64_t)pte_mapped, + (uint64_t)pte_mapped + pagesize * 4); + + /* smap does not show THPs after mremap, use kpageflags instead */ + thp_size = 0; + for (i = 0; i < pagesize * 4; i++) { + if (pte_mapped[i] != (char)i) { + printf("%ld byte corrupted\n", i); + exit(EXIT_FAILURE); + } + if (i % pagesize == 0 && + is_backed_by_thp(&pte_mapped[i], pagemap_fd, kpageflags_fd)) + thp_size++; + } + + if (thp_size) { + printf("Still %ld THPs not split\n", thp_size); + exit(EXIT_FAILURE); + } + + printf("Split PTE-mapped huge pages successful\n"); + munmap(one_page, len); + close(pagemap_fd); + close(kpageflags_fd); +} + +int main(int argc, char **argv) +{ + if (geteuid() != 0) { + printf("Please run the benchmark as root\n"); + exit(EXIT_FAILURE); + } + + pagesize = getpagesize(); + pageshift = ffs(pagesize) - 1; + pmd_pagesize = read_pmd_pagesize(); + + split_pmd_thp(); + split_pte_mapped_thp(); + + return 0; +} -- 2.30.2

4 years, 3 months

3
5
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[PATCH] kselftest/arm64: sve: Do not use non-canonical FFR register value

by Andre Przywara

The "First Fault Register" (FFR) is an SVE register that mimics a predicate register, but clears bits when a load or store fails to handle an element of a vector. The supposed usage scenario is to initialise this register (using SETFFR), then *read* it later on to learn about elements that failed to load or store. Explicit writes to this register using the WRFFR instruction are only supposed to *restore* values previously read from the register (for context-switching only). As the manual describes, this register holds only certain values, it: "... contains a monotonic predicate value, in which starting from bit 0 there are zero or more 1 bits, followed only by 0 bits in any remaining bit positions." Any other value is UNPREDICTABLE and is not supposed to be "restored" into the register. The SVE test currently tries to write a signature pattern into the register, which is *not* a canonical FFR value. Apparently the existing setups treat UNPREDICTABLE as "read-as-written", but a new implementation actually only stores canonical values. As a consequence, the sve-test fails immediately when comparing the FFR value: ----------- # ./sve-test Vector length: 128 bits PID: 207 Mismatch: PID=207, iteration=0, reg=48 Expected [cf00] Got [0f00] Aborted ----------- Fix this by only populating the FFR with proper canonical values. Effectively the requirement described above limits us to 17 unique values over 16 bits worth of FFR, so we condense our signature down to 4 bits (2 bits from the PID, 2 bits from the generation) and generate the canonical pattern from it. Any bits describing elements above the minimum 128 bit are set to 0. This aligns the FFR usage to the architecture and fixes the test on microarchitectures implementing FFR in a more restricted way. Signed-off-by: Andre Przywara <andre.przywara(a)arm.com> --- tools/testing/selftests/arm64/fp/sve-test.S | 22 ++++++++++++++++----- 1 file changed, 17 insertions(+), 5 deletions(-) diff --git a/tools/testing/selftests/arm64/fp/sve-test.S b/tools/testing/selftests/arm64/fp/sve-test.S index 9210691aa998..e3e08d9c7020 100644 --- a/tools/testing/selftests/arm64/fp/sve-test.S +++ b/tools/testing/selftests/arm64/fp/sve-test.S @@ -284,16 +284,28 @@ endfunction // Set up test pattern in the FFR // x0: pid // x2: generation +// +// We need to generate a canonical FFR value, which consists of a number of +// low "1" bits, followed by a number of zeros. This gives us 17 unique values +// per 16 bits of FFR, so we create a 4 bit signature out of the PID and +// generation, and use that as the initial number of ones in the pattern. +// We fill the upper lanes of FFR with zeros. // Beware: corrupts P0. function setup_ffr mov x4, x30 - bl pattern + and w0, w0, #0x3 + bfi w0, w2, #2, #2 + mov w1, #1 + lsl w1, w1, w0 + sub w1, w1, #1 + ldr x0, =ffrref - ldr x1, =scratch - rdvl x2, #1 - lsr x2, x2, #3 - bl memcpy + strh w1, [x0], 2 + rdvl x1, #1 + lsr x1, x1, #3 + sub x1, x1, #2 + bl memclr mov x0, #0 ldr x1, =ffrref -- 2.25.1

4 years, 3 months

3
2
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[RFC 0/2] CPU-Idle latency selftest framework

by Pratik Rajesh Sampat

A kernel module + userspace driver to estimate the wakeup latency caused by going into stop states. The motivation behind this program is to find significant deviations behind advertised latency and residency values. The patchset measures latencies for two kinds of events. IPIs and Timers As this is a software-only mechanism, there will additional latencies of the kernel-firmware-hardware interactions. To account for that, the program also measures a baseline latency on a 100 percent loaded CPU and the latencies achieved must be in view relative to that. To achieve this, we introduce a kernel module and expose its control knobs through the debugfs interface that the selftests can engage with. The kernel module provides the following interfaces within /sys/kernel/debug/latency_test/ for, IPI test: ipi_cpu_dest = Destination CPU for the IPI ipi_cpu_src = Origin of the IPI ipi_latency_ns = Measured latency time in ns Timeout test: timeout_cpu_src = CPU on which the timer to be queued timeout_expected_ns = Timer duration timeout_diff_ns = Difference of actual duration vs expected timer Sample output on a POWER9 system is as follows: # --IPI Latency Test--- # Baseline Average IPI latency(ns): 3114 # Observed Average IPI latency(ns) - State0: 3265 # Observed Average IPI latency(ns) - State1: 3507 # Observed Average IPI latency(ns) - State2: 3739 # Observed Average IPI latency(ns) - State3: 3807 # Observed Average IPI latency(ns) - State4: 17070 # Observed Average IPI latency(ns) - State5: 1038174 # Observed Average IPI latency(ns) - State6: 1068784 # # --Timeout Latency Test-- # Baseline Average timeout diff(ns): 1420 # Observed Average timeout diff(ns) - State0: 1640 # Observed Average timeout diff(ns) - State1: 1764 # Observed Average timeout diff(ns) - State2: 1715 # Observed Average timeout diff(ns) - State3: 1845 # Observed Average timeout diff(ns) - State4: 16581 # Observed Average timeout diff(ns) - State5: 939977 # Observed Average timeout diff(ns) - State6: 1073024 Things to keep in mind: 1. This kernel module + bash driver does not guarantee idleness on a core when the IPI and the Timer is armed. It only invokes sleep and hopes that the core is idle once the IPI/Timer is invoked onto it. Hence this program must be run on a completely idle system for best results 2. Even on a completely idle system, there maybe book-keeping tasks or jitter tasks that can run on the core we want idle. This can create outliers in the latency measurement. Thankfully, these outliers should be large enough to easily weed them out. 3. A userspace only selftest variant was also sent out as RFC based on suggestions over the previous patchset to simply the kernel complexeity. However, a userspace only approach had more noise in the latency measurement due to userspace-kernel interactions which led to run to run variance and a lesser accurate test. Another downside of the nature of a userspace program is that it takes orders of magnitude longer to complete a full system test compared to the kernel framework. RFC patch: https://lkml.org/lkml/2020/9/2/356 4. For Intel Systems, the Timer based latencies don't exactly give out the measure of idle latencies. This is because of a hardware optimization mechanism that pre-arms a CPU when a timer is set to wakeup. That doesn't make this metric useless for Intel systems, it just means that is measuring IPI/Timer responding latency rather than idle wakeup latencies. (Source: https://lkml.org/lkml/2020/9/2/610) For solution to this problem, a hardware based latency analyzer is devised by Artem Bityutskiy from Intel. https://youtu.be/Opk92aQyvt0?t=8266 https://intel.github.io/wult/ Pratik Rajesh Sampat (2): cpuidle: Extract IPI based and timer based wakeup latency from idle states selftest/cpuidle: Add support for cpuidle latency measurement drivers/cpuidle/Makefile | 1 + drivers/cpuidle/test-cpuidle_latency.c | 157 ++++++++++ lib/Kconfig.debug | 10 + tools/testing/selftests/Makefile | 1 + tools/testing/selftests/cpuidle/Makefile | 6 + tools/testing/selftests/cpuidle/cpuidle.sh | 316 +++++++++++++++++++++ tools/testing/selftests/cpuidle/settings | 2 + 7 files changed, 493 insertions(+) create mode 100644 drivers/cpuidle/test-cpuidle_latency.c create mode 100644 tools/testing/selftests/cpuidle/Makefile create mode 100755 tools/testing/selftests/cpuidle/cpuidle.sh create mode 100644 tools/testing/selftests/cpuidle/settings -- 2.17.1

4 years, 3 months

3
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[RFC PATCH v4 0/9] KVM: selftests: some improvement and a new test for kvm page table

by Yanan Wang

Hi, This v4 series can mainly include two parts. Based on kvm queue branch: https://git.kernel.org/pub/scm/virt/kvm/kvm.git/log/?h=queue Links of v1: https://lore.kernel.org/lkml/20210208090841.333724-1-wangyanan55@huawei.com/ Links of v2: https://lore.kernel.org/lkml/20210225055940.18748-1-wangyanan55@huawei.com/ Links of v3: https://lore.kernel.org/lkml/20210301065916.11484-1-wangyanan55@huawei.com/ In the first part, all the known hugetlb backing src types specified with different hugepage sizes are listed, so that we can specify use of hugetlb source of the exact granularity that we want, instead of the system default ones. And as all the known hugetlb page sizes are listed, it's appropriate for all architectures. Besides, a helper that can get granularity of different backing src types(anonumous/thp/hugetlb) is added, so that we can use the accurate backing src granularity for kinds of alignment or guest memory accessing of vcpus. In the second part, a new test is added: This test is added to serve as a performance tester and a bug reproducer for kvm page table code (GPA->HPA mappings), it gives guidance for the people trying to make some improvement for kvm. And the following explains what we can exactly do through this test. The function guest_code() can cover the conditions where a single vcpu or multiple vcpus access guest pages within the same memory region, in three VM stages(before dirty logging, during dirty logging, after dirty logging). Besides, the backing src memory type(ANONYMOUS/THP/HUGETLB) of the tested memory region can be specified by users, which means normal page mappings or block mappings can be chosen by users to be created in the test. If ANONYMOUS memory is specified, kvm will create normal page mappings for the tested memory region before dirty logging, and update attributes of the page mappings from RO to RW during dirty logging. If THP/HUGETLB memory is specified, kvm will create block mappings for the tested memory region before dirty logging, and split the blcok mappings into normal page mappings during dirty logging, and coalesce the page mappings back into block mappings after dirty logging is stopped. So in summary, as a performance tester, this test can present the performance of kvm creating/updating normal page mappings, or the performance of kvm creating/splitting/recovering block mappings, through execution time. When we need to coalesce the page mappings back to block mappings after dirty logging is stopped, we have to firstly invalidate *all* the TLB entries for the page mappings right before installation of the block entry, because a TLB conflict abort error could occur if we can't invalidate the TLB entries fully. We have hit this TLB conflict twice on aarch64 software implementation and fixed it. As this test can imulate process from dirty logging enabled to dirty logging stopped of a VM with block mappings, so it can also reproduce this TLB conflict abort due to inadequate TLB invalidation when coalescing tables. Links about the TLB conflict abort: https://lore.kernel.org/lkml/20201201201034.116760-3-wangyanan55@huawei.com/ --- Change logs: v3->v4: - Add a helper to get system default hugetlb page size - Add tags of Reviewed-by of Ben in the patches v2->v3: - Add tags of Suggested-by, Reviewed-by in the patches - Add a generic micro to get hugetlb page sizes - Some changes for suggestions about v2 series v1->v2: - Add a patch to sync header files - Add helpers to get granularity of different backing src types - Some changes for suggestions about v1 series --- Yanan Wang (9): tools headers: sync headers of asm-generic/hugetlb_encode.h tools headers: Add a macro to get HUGETLB page sizes for mmap KVM: selftests: Use flag CLOCK_MONOTONIC_RAW for timing KVM: selftests: Make a generic helper to get vm guest mode strings KVM: selftests: Add a helper to get system configured THP page size KVM: selftests: Add a helper to get system default hugetlb page size KVM: selftests: List all hugetlb src types specified with page sizes KVM: selftests: Adapt vm_userspace_mem_region_add to new helpers KVM: selftests: Add a test for kvm page table code include/uapi/linux/mman.h | 2 + tools/include/asm-generic/hugetlb_encode.h | 3 + tools/include/uapi/linux/mman.h | 2 + tools/testing/selftests/kvm/Makefile | 3 + .../selftests/kvm/demand_paging_test.c | 8 +- .../selftests/kvm/dirty_log_perf_test.c | 14 +- .../testing/selftests/kvm/include/kvm_util.h | 4 +- .../testing/selftests/kvm/include/test_util.h | 21 +- .../selftests/kvm/kvm_page_table_test.c | 476 ++++++++++++++++++ tools/testing/selftests/kvm/lib/kvm_util.c | 59 ++- tools/testing/selftests/kvm/lib/test_util.c | 122 ++++- tools/testing/selftests/kvm/steal_time.c | 4 +- 12 files changed, 659 insertions(+), 59 deletions(-) create mode 100644 tools/testing/selftests/kvm/kvm_page_table_test.c -- 2.19.1

4 years, 3 months

3
24
0 0

[PATCH bpf-next 0/2] add support for batched ops in LPM trie

by Pedro Tammela

The patch itself is straightforward thanks to the infrastructure that is already in-place. The tests follows the other '*_map_batch_ops' tests with minor tweaks. Pedro Tammela (2): bpf: add support for batched operations in LPM trie maps bpf: selftests: add tests for batched ops in LPM trie maps kernel/bpf/lpm_trie.c | 3 + .../map_tests/lpm_trie_map_batch_ops.c (new) | 158 ++++++++++++++++++ 2 files changed, 161 insertions(+) create mode 100644 tools/testing/selftests/bpf/map_tests/lpm_trie_map_batch_ops.c -- 2.25.1

4 years, 3 months

1
2
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[PATCH] selftests: net: forwarding: Fix a typo

by Bhaskar Chowdhury

s/verfied/verified/ Signed-off-by: Bhaskar Chowdhury <unixbhaskar(a)gmail.com> --- tools/testing/selftests/net/forwarding/fib_offload_lib.sh | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/tools/testing/selftests/net/forwarding/fib_offload_lib.sh b/tools/testing/selftests/net/forwarding/fib_offload_lib.sh index 66496659bea7..e134a5f529c9 100644 --- a/tools/testing/selftests/net/forwarding/fib_offload_lib.sh +++ b/tools/testing/selftests/net/forwarding/fib_offload_lib.sh @@ -224,7 +224,7 @@ fib_ipv4_plen_test() ip -n $ns link set dev dummy1 up # Add two routes with the same key and different prefix length and - # make sure both are in hardware. It can be verfied that both are + # make sure both are in hardware. It can be verified that both are # sharing the same leaf by checking the /proc/net/fib_trie ip -n $ns route add 192.0.2.0/24 dev dummy1 ip -n $ns route add 192.0.2.0/25 dev dummy1 -- 2.26.2

4 years, 3 months

2
1
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