November 2020 - Linux-kselftest-mirror

[PATCH v11 0/9] mm: introduce memfd_secret system call to create "secret" memory areas

by Mike Rapoport

From: Mike Rapoport <rppt(a)linux.ibm.com> Hi, This is an implementation of "secret" mappings backed by a file descriptor. The file descriptor backing secret memory mappings is created using a dedicated memfd_secret system call The desired protection mode for the memory is configured using flags parameter of the system call. The mmap() of the file descriptor created with memfd_secret() will create a "secret" memory mapping. The pages in that mapping will be marked as not present in the direct map and will be present only in the page table of the owning mm. Although normally Linux userspace mappings are protected from other users, such secret mappings are useful for environments where a hostile tenant is trying to trick the kernel into giving them access to other tenants mappings. Additionally, in the future the secret mappings may be used as a mean to protect guest memory in a virtual machine host. For demonstration of secret memory usage we've created a userspace library https://git.kernel.org/pub/scm/linux/kernel/git/jejb/secret-memory-preloade… that does two things: the first is act as a preloader for openssl to redirect all the OPENSSL_malloc calls to secret memory meaning any secret keys get automatically protected this way and the other thing it does is expose the API to the user who needs it. We anticipate that a lot of the use cases would be like the openssl one: many toolkits that deal with secret keys already have special handling for the memory to try to give them greater protection, so this would simply be pluggable into the toolkits without any need for user application modification. Hiding secret memory mappings behind an anonymous file allows (ab)use of the page cache for tracking pages allocated for the "secret" mappings as well as using address_space_operations for e.g. page migration callbacks. The anonymous file may be also used implicitly, like hugetlb files, to implement mmap(MAP_SECRET) and use the secret memory areas with "native" mm ABIs in the future. To limit fragmentation of the direct map to splitting only PUD-size pages, I've added an amortizing cache of PMD-size pages to each file descriptor that is used as an allocation pool for the secret memory areas. As the memory allocated by secretmem becomes unmovable, we use CMA to back large page caches so that page allocator won't be surprised by failing attempt to migrate these pages. v11: * Drop support for uncached mappings v10: https://lore.kernel.org/lkml/20201123095432.5860-1-rppt@kernel.org * Drop changes to arm64 compatibility layer * Add Roman's Ack for memcg accounting v9: https://lore.kernel.org/lkml/20201117162932.13649-1-rppt@kernel.org * Fix build with and without CONFIG_MEMCG * Update memcg accounting to avoid copying memcg_data, per Roman comments * Fix issues in secretmem_fault(), thanks Matthew * Do not wire up syscall in arm64 compatibility layer v8: https://lore.kernel.org/lkml/20201110151444.20662-1-rppt@kernel.org * Use CMA for all secretmem allocations as David suggested * Update memcg accounting after transtion to CMA * Prevent hibernation when there are active secretmem users * Add zeroing of the memory before releasing it back to cma/page allocator * Rebase on v5.10-rc2-mmotm-2020-11-07-21-40 v7: https://lore.kernel.org/lkml/20201026083752.13267-1-rppt@kernel.org * Use set_direct_map() instead of __kernel_map_pages() to ensure error handling in case the direct map update fails * Add accounting of large pages used to reduce the direct map fragmentation * Teach get_user_pages() and frieds to refuse get/pin secretmem pages v6: https://lore.kernel.org/lkml/20200924132904.1391-1-rppt@kernel.org * Silence the warning about missing syscall, thanks to Qian Cai * Replace spaces with tabs in Kconfig additions, per Randy * Add a selftest. Older history: v5: https://lore.kernel.org/lkml/20200916073539.3552-1-rppt@kernel.org v4: https://lore.kernel.org/lkml/20200818141554.13945-1-rppt@kernel.org v3: https://lore.kernel.org/lkml/20200804095035.18778-1-rppt@kernel.org v2: https://lore.kernel.org/lkml/20200727162935.31714-1-rppt@kernel.org v1: https://lore.kernel.org/lkml/20200720092435.17469-1-rppt@kernel.org Mike Rapoport (9): mm: add definition of PMD_PAGE_ORDER mmap: make mlock_future_check() global set_memory: allow set_direct_map_*_noflush() for multiple pages mm: introduce memfd_secret system call to create "secret" memory areas secretmem: use PMD-size pages to amortize direct map fragmentation secretmem: add memcg accounting PM: hibernate: disable when there are active secretmem users arch, mm: wire up memfd_secret system call were relevant secretmem: test: add basic selftest for memfd_secret(2) arch/arm64/include/asm/cacheflush.h | 4 +- arch/arm64/include/uapi/asm/unistd.h | 1 + arch/arm64/mm/pageattr.c | 10 +- arch/riscv/include/asm/set_memory.h | 4 +- arch/riscv/include/asm/unistd.h | 1 + arch/riscv/mm/pageattr.c | 8 +- arch/x86/Kconfig | 2 +- arch/x86/entry/syscalls/syscall_32.tbl | 1 + arch/x86/entry/syscalls/syscall_64.tbl | 1 + arch/x86/include/asm/set_memory.h | 4 +- arch/x86/mm/pat/set_memory.c | 8 +- fs/dax.c | 11 +- include/linux/pgtable.h | 3 + include/linux/secretmem.h | 30 ++ include/linux/set_memory.h | 4 +- include/linux/syscalls.h | 1 + include/uapi/asm-generic/unistd.h | 6 +- include/uapi/linux/magic.h | 1 + kernel/power/hibernate.c | 5 +- kernel/power/snapshot.c | 4 +- kernel/sys_ni.c | 2 + mm/Kconfig | 5 + mm/Makefile | 1 + mm/filemap.c | 3 +- mm/gup.c | 10 + mm/internal.h | 3 + mm/mmap.c | 5 +- mm/secretmem.c | 436 ++++++++++++++++++++++ mm/vmalloc.c | 5 +- scripts/checksyscalls.sh | 4 + tools/testing/selftests/vm/.gitignore | 1 + tools/testing/selftests/vm/Makefile | 3 +- tools/testing/selftests/vm/memfd_secret.c | 298 +++++++++++++++ tools/testing/selftests/vm/run_vmtests | 17 + 34 files changed, 863 insertions(+), 39 deletions(-) create mode 100644 include/linux/secretmem.h create mode 100644 mm/secretmem.c create mode 100644 tools/testing/selftests/vm/memfd_secret.c base-commit: 9f8ce377d420db12b19d6a4f636fecbd88a725a5 -- 2.28.0

4 years, 1 month

2
11
0 0

[PATCH v4 0/2] dma-mapping: provide a benchmark for streaming DMA mapping

by Barry Song

Nowadays, there are increasing requirements to benchmark the performance of dma_map and dma_unmap particually while the device is attached to an IOMMU. This patchset provides the benchmark infrastruture for streaming DMA mapping. The architecture of the code is pretty much similar with GUP benchmark: * mm/gup_benchmark.c provides kernel interface; * tools/testing/selftests/vm/gup_benchmark.c provides user program to call the interface provided by mm/gup_benchmark.c. In our case, kernel/dma/map_benchmark.c is like mm/gup_benchmark.c; tools/testing/selftests/dma/dma_map_benchmark.c is like tools/testing/ selftests/vm/gup_benchmark.c A major difference with GUP benchmark is DMA_MAP benchmark needs to run on a device. Considering one board with below devices and IOMMUs device A ------- IOMMU 1 device B ------- IOMMU 2 device C ------- non-IOMMU Different devices might attach to different IOMMU or non-IOMMU. To make benchmark run, we can either * create a virtual device and hack the kernel code to attach the virtual device to IOMMU1, IOMMU2 or non-IOMMU. * use the existing driver_override mechinism, unbind device A,B, OR c from their original driver and bind A to dma_map_benchmark platform driver or pci driver for benchmarking. In this patchset, I prefer to use the driver_override and avoid the ugly hack in kernel. We can dynamically switch device behind different IOMMUs to get the performance of IOMMU or non-IOMMU. -v4: * add dma direction support according to Christoph Hellwig's comment; * add dma mask bit set according to Christoph Hellwig's comment; * make the benchmark depend on DEBUG_FS according to John Garry's comment; * strictly check parameters in ioctl -v3: * fix build issues reported by 0day kernel test robot -v2: * add PCI support; v1 supported platform devices only * replace ssleep by msleep_interruptible() to permit users to exit benchmark before it is completed * many changes according to Robin's suggestions, thanks! Robin - add standard deviation output to reflect the worst case - check users' parameters strictly like the number of threads - make cache dirty before dma_map - fix unpaired dma_map_page and dma_unmap_single; - remove redundant "long long" before ktime_to_ns(); - use devm_add_action() Barry Song (2): dma-mapping: add benchmark support for streaming DMA APIs selftests/dma: add test application for DMA_MAP_BENCHMARK MAINTAINERS | 6 + kernel/dma/Kconfig | 9 + kernel/dma/Makefile | 1 + kernel/dma/map_benchmark.c | 361 ++++++++++++++++++ tools/testing/selftests/dma/Makefile | 6 + tools/testing/selftests/dma/config | 1 + .../testing/selftests/dma/dma_map_benchmark.c | 123 ++++++ 7 files changed, 507 insertions(+) create mode 100644 kernel/dma/map_benchmark.c create mode 100644 tools/testing/selftests/dma/Makefile create mode 100644 tools/testing/selftests/dma/config create mode 100644 tools/testing/selftests/dma/dma_map_benchmark.c -- 2.25.1

4 years, 1 month

2
3
0 0

[PATCH v10 0/9] mm: introduce memfd_secret system call to create "secret" memory areas

by Mike Rapoport

From: Mike Rapoport <rppt(a)linux.ibm.com> Hi, This is an implementation of "secret" mappings backed by a file descriptor. The file descriptor backing secret memory mappings is created using a dedicated memfd_secret system call The desired protection mode for the memory is configured using flags parameter of the system call. The mmap() of the file descriptor created with memfd_secret() will create a "secret" memory mapping. The pages in that mapping will be marked as not present in the direct map and will have desired protection bits set in the user page table. For instance, current implementation allows uncached mappings. Although normally Linux userspace mappings are protected from other users, such secret mappings are useful for environments where a hostile tenant is trying to trick the kernel into giving them access to other tenants mappings. Additionally, in the future the secret mappings may be used as a mean to protect guest memory in a virtual machine host. For demonstration of secret memory usage we've created a userspace library https://git.kernel.org/pub/scm/linux/kernel/git/jejb/secret-memory-preloade… that does two things: the first is act as a preloader for openssl to redirect all the OPENSSL_malloc calls to secret memory meaning any secret keys get automatically protected this way and the other thing it does is expose the API to the user who needs it. We anticipate that a lot of the use cases would be like the openssl one: many toolkits that deal with secret keys already have special handling for the memory to try to give them greater protection, so this would simply be pluggable into the toolkits without any need for user application modification. Hiding secret memory mappings behind an anonymous file allows (ab)use of the page cache for tracking pages allocated for the "secret" mappings as well as using address_space_operations for e.g. page migration callbacks. The anonymous file may be also used implicitly, like hugetlb files, to implement mmap(MAP_SECRET) and use the secret memory areas with "native" mm ABIs in the future. To limit fragmentation of the direct map to splitting only PUD-size pages, I've added an amortizing cache of PMD-size pages to each file descriptor that is used as an allocation pool for the secret memory areas. As the memory allocated by secretmem becomes unmovable, we use CMA to back large page caches so that page allocator won't be surprised by failing attempt to migrate these pages. v10: * Drop changes to arm64 compatibility layer * Add Roman's Ack for memcg accounting v9: https://lore.kernel.org/lkml/20201117162932.13649-1-rppt@kernel.org * Fix build with and without CONFIG_MEMCG * Update memcg accounting to avoid copying memcg_data, per Roman comments * Fix issues in secretmem_fault(), thanks Matthew * Do not wire up syscall in arm64 compatibility layer v8: https://lore.kernel.org/lkml/20201110151444.20662-1-rppt@kernel.org * Use CMA for all secretmem allocations as David suggested * Update memcg accounting after transtion to CMA * Prevent hibernation when there are active secretmem users * Add zeroing of the memory before releasing it back to cma/page allocator * Rebase on v5.10-rc2-mmotm-2020-11-07-21-40 v7: https://lore.kernel.org/lkml/20201026083752.13267-1-rppt@kernel.org * Use set_direct_map() instead of __kernel_map_pages() to ensure error handling in case the direct map update fails * Add accounting of large pages used to reduce the direct map fragmentation * Teach get_user_pages() and frieds to refuse get/pin secretmem pages v6: https://lore.kernel.org/lkml/20200924132904.1391-1-rppt@kernel.org * Silence the warning about missing syscall, thanks to Qian Cai * Replace spaces with tabs in Kconfig additions, per Randy * Add a selftest. Older history: v5: https://lore.kernel.org/lkml/20200916073539.3552-1-rppt@kernel.org v4: https://lore.kernel.org/lkml/20200818141554.13945-1-rppt@kernel.org v3: https://lore.kernel.org/lkml/20200804095035.18778-1-rppt@kernel.org v2: https://lore.kernel.org/lkml/20200727162935.31714-1-rppt@kernel.org v1: https://lore.kernel.org/lkml/20200720092435.17469-1-rppt@kernel.org Mike Rapoport (9): mm: add definition of PMD_PAGE_ORDER mmap: make mlock_future_check() global set_memory: allow set_direct_map_*_noflush() for multiple pages mm: introduce memfd_secret system call to create "secret" memory areas secretmem: use PMD-size pages to amortize direct map fragmentation secretmem: add memcg accounting PM: hibernate: disable when there are active secretmem users arch, mm: wire up memfd_secret system call were relevant secretmem: test: add basic selftest for memfd_secret(2) arch/Kconfig | 7 + arch/arm64/include/asm/cacheflush.h | 4 +- arch/arm64/include/uapi/asm/unistd.h | 1 + arch/arm64/mm/pageattr.c | 10 +- arch/riscv/include/asm/set_memory.h | 4 +- arch/riscv/include/asm/unistd.h | 1 + arch/riscv/mm/pageattr.c | 8 +- arch/x86/Kconfig | 1 + arch/x86/entry/syscalls/syscall_32.tbl | 1 + arch/x86/entry/syscalls/syscall_64.tbl | 1 + arch/x86/include/asm/set_memory.h | 4 +- arch/x86/mm/pat/set_memory.c | 8 +- fs/dax.c | 11 +- include/linux/pgtable.h | 3 + include/linux/secretmem.h | 30 ++ include/linux/set_memory.h | 4 +- include/linux/syscalls.h | 1 + include/uapi/asm-generic/unistd.h | 6 +- include/uapi/linux/magic.h | 1 + include/uapi/linux/secretmem.h | 8 + kernel/power/hibernate.c | 5 +- kernel/power/snapshot.c | 4 +- kernel/sys_ni.c | 2 + mm/Kconfig | 5 + mm/Makefile | 1 + mm/filemap.c | 3 +- mm/gup.c | 10 + mm/internal.h | 3 + mm/mmap.c | 5 +- mm/secretmem.c | 446 ++++++++++++++++++++++ mm/vmalloc.c | 5 +- scripts/checksyscalls.sh | 4 + tools/testing/selftests/vm/.gitignore | 1 + tools/testing/selftests/vm/Makefile | 3 +- tools/testing/selftests/vm/memfd_secret.c | 298 +++++++++++++++ tools/testing/selftests/vm/run_vmtests | 17 + 36 files changed, 888 insertions(+), 38 deletions(-) create mode 100644 include/linux/secretmem.h create mode 100644 include/uapi/linux/secretmem.h create mode 100644 mm/secretmem.c create mode 100644 tools/testing/selftests/vm/memfd_secret.c base-commit: 9f8ce377d420db12b19d6a4f636fecbd88a725a5 -- 2.28.0

4 years, 1 month

3
12
0 0

[PATCH v24 00/12] Landlock LSM

by Mickaël Salaün

Hi, This patch series simplifies the code, makes stacked access-control more consistent (from the user point of view), properly handles memory allocation errors, and adds more tests (covering layered ruleset corner cases). Most of these changes were sent as a separate patch series: https://lore.kernel.org/lkml/20201111213442.434639-1-mic@digikod.net/ James and Jann, could you please take a look at the main changes (patches 2, 7 and 8)? The SLOC count is 1185 for security/landlock/ and 1767 for tools/testing/selftest/landlock/ . Test coverage for security/landlock/ is 94.8% of lines. The code not covered only deals with internal kernel errors (e.g. memory allocation) and race conditions. The compiled documentation is available here: https://landlock.io/linux-doc/landlock-v24/userspace-api/landlock.html This series can be applied on top of v5.10-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-v24 I would really appreciate constructive comments on this patch series. # 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]. Previous version: https://lore.kernel.org/lkml/20201103182109.1014179-1-mic@digikod.net/ [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… 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 | 275 +++ MAINTAINERS | 13 + 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 | 3 + 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 | 15 + samples/landlock/sandboxer.c | 236 +++ 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 | 608 ++++++ security/landlock/fs.h | 60 + security/landlock/object.c | 67 + security/landlock/object.h | 91 + security/landlock/ptrace.c | 120 ++ security/landlock/ptrace.h | 14 + security/landlock/ruleset.c | 361 ++++ security/landlock/ruleset.h | 158 ++ security/landlock/setup.c | 40 + security/landlock/setup.h | 18 + security/landlock/syscall.c | 426 ++++ 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 | 117 ++ tools/testing/selftests/landlock/common.h | 113 + tools/testing/selftests/landlock/config | 5 + tools/testing/selftests/landlock/fs_test.c | 1824 +++++++++++++++++ .../testing/selftests/landlock/ptrace_test.c | 307 +++ tools/testing/selftests/landlock/true.c | 5 + 71 files changed, 5455 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/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/syscall.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: f8394f232b1eab649ce2df5c5f15b0e528c92091 -- 2.29.2

4 years, 1 month

3
26
0 0

[PATCH] Documentation: kunit: provide guidance for testing many inputs

by Daniel Latypov

usage.rst goes into a detailed about faking out classes, but currently lacks wording about how one might idiomatically test a range of inputs. Give an example of how one might test a hash function via macros/helper funcs and a table-driven test and very briefly discuss pros and cons. Also highlight the KUNIT_EXPECT_*_MSG() variants (that aren't mentioned elsewhere [1]) which are particularly useful in these situations. It is also criminally underused at the moment, only appearing in 2 tests (both written by people involved in KUnit). [1] not even on https://www.kernel.org/doc/html/latest/dev-tools/kunit/api/test.html Signed-off-by: Daniel Latypov <dlatypov(a)google.com> --- Documentation/dev-tools/kunit/usage.rst | 66 +++++++++++++++++++++++++ 1 file changed, 66 insertions(+) diff --git a/Documentation/dev-tools/kunit/usage.rst b/Documentation/dev-tools/kunit/usage.rst index 62142a47488c..317390df2b96 100644 --- a/Documentation/dev-tools/kunit/usage.rst +++ b/Documentation/dev-tools/kunit/usage.rst @@ -451,6 +451,72 @@ We can now use it to test ``struct eeprom_buffer``: destroy_eeprom_buffer(ctx->eeprom_buffer); } +Testing various inputs +---------------------- + +Testing just a few inputs might not be enough to have confidence that the code +works correctly, e.g. for a hash function. + +In such cases, it can be helpful to have a helper macro or function, e.g. this +fictitious example for ``md5sum(1)`` + +.. code-block:: c + + /* Note: the cast is to satisfy overly strict type-checking. */ + #define TEST_MD5(in, want) \ + md5sum(in, out); \ + KUNIT_EXPECT_STREQ_MSG(test, (char *)out, want, "md5sum(%s)", in); + + char out[16]; + TEST_MD5("hello world", "5eb63bbbe01eeed093cb22bb8f5acdc3"); + TEST_MD5("hello world!", "fc3ff98e8c6a0d3087d515c0473f8677"); + +Note the use of ``KUNIT_EXPECT_STREQ_MSG`` to give more context when it fails +and make it easier to track down. (Yes, in this example, ``want`` is likely +going to be unique enough on its own). + +The ``_MSG`` variants are even more useful when the same expectation is called +multiple times (in a loop or helper function) and thus the line number isn't +enough to identify what failed, like below. + +In some cases, it can be helpful to write a *table-driven test* instead, e.g. + +.. code-block:: c + + int i; + char out[16]; + + struct md5_test_case { + const char *str; + const char *md5; + }; + + struct md5_test_case cases[] = { + { + .str = "hello world", + .md5 = "5eb63bbbe01eeed093cb22bb8f5acdc3", + }, + { + .str = "hello world!", + .md5 = "fc3ff98e8c6a0d3087d515c0473f8677", + }, + }; + for (i = 0; i < ARRAY_SIZE(cases); ++i) { + md5sum(cases[i].str, out); + KUNIT_EXPECT_STREQ_MSG(test, (char *)out, cases[i].md5, + "md5sum(%s)", cases[i].str); + } + + +There's more boilerplate involved, but it can: + +* be more readable when there are multiple inputs/outputs thanks to field names, + + * E.g. see ``fs/ext4/inode-test.c`` for an example of both. +* reduce duplication if test cases can be shared across multiple tests. + + * E.g. if we had a magical ``undo_md5sum`` function, we could reuse ``cases``. + .. _kunit-on-non-uml: KUnit on non-UML architectures base-commit: 77c8473edf7f7664137f555cfcdc8c460bbd947d -- 2.29.1.341.ge80a0c044ae-goog

4 years, 1 month

3
4
0 0

[PATCH v7 0/7] Syscall User Dispatch

by Gabriel Krisman Bertazi

Hi, This is the v7 of syscall user dispatch. This version is a bit different from v6 on the following points, after the modifications requested on that submission. * The interface no longer receives <start>,<end> end parameters, but <start>,<length> as suggested by PeterZ. * Syscall User Dispatch is now done before ptrace, and this means there is some SYSCALL_WORK_EXIT work that needs to be done. No challenges there, but I'd like to draw attention to that region of the code that is new in this submission. * The previous TIF_SYSCALL_USER_DISPATCH is now handled through SYSCALL_WORK flags. * Introduced a new test as patch 6, which benchmarks the fast submission path and test the return in blocked selector state. * Nothing is architecture dependent anymore. No config switches. It only depends on CONFIG_GENERIC_ENTRY. Other smaller changes are documented one each commit. This was tested using the kselftests tests in patch 5 and 6 and compiled tested with !CONFIG_GENERIC_ENTRY. This patchset is based on the core/entry branch of the TIP tree. A working tree with this patchset is available at: https://gitlab.collabora.com/krisman/linux -b syscall-user-dispatch-v7 Previous submissions are archived at: RFC/v1: https://lkml.org/lkml/2020/7/8/96 v2: https://lkml.org/lkml/2020/7/9/17 v3: https://lkml.org/lkml/2020/7/12/4 v4: https://www.spinics.net/lists/linux-kselftest/msg16377.html v5: https://lkml.org/lkml/2020/8/10/1320 v6: https://lkml.org/lkml/2020/9/4/1122 Gabriel Krisman Bertazi (7): x86: vdso: Expose sigreturn address on vdso to the kernel signal: Expose SYS_USER_DISPATCH si_code type kernel: Implement selective syscall userspace redirection entry: Support Syscall User Dispatch on common syscall entry selftests: Add kselftest for syscall user dispatch selftests: Add benchmark for syscall user dispatch docs: Document Syscall User Dispatch .../admin-guide/syscall-user-dispatch.rst | 87 +++++ arch/x86/entry/vdso/vdso2c.c | 2 + arch/x86/entry/vdso/vdso32/sigreturn.S | 2 + arch/x86/entry/vdso/vma.c | 15 + arch/x86/include/asm/elf.h | 2 + arch/x86/include/asm/vdso.h | 2 + arch/x86/kernel/signal_compat.c | 2 +- fs/exec.c | 3 + include/linux/entry-common.h | 2 + include/linux/sched.h | 2 + include/linux/syscall_user_dispatch.h | 40 +++ include/linux/thread_info.h | 2 + include/uapi/asm-generic/siginfo.h | 3 +- include/uapi/linux/prctl.h | 5 + kernel/entry/Makefile | 2 +- kernel/entry/common.c | 17 + kernel/entry/common.h | 16 + kernel/entry/syscall_user_dispatch.c | 102 ++++++ kernel/fork.c | 1 + kernel/sys.c | 5 + tools/testing/selftests/Makefile | 1 + .../syscall_user_dispatch/.gitignore | 3 + .../selftests/syscall_user_dispatch/Makefile | 9 + .../selftests/syscall_user_dispatch/config | 1 + .../syscall_user_dispatch/sud_benchmark.c | 200 +++++++++++ .../syscall_user_dispatch/sud_test.c | 310 ++++++++++++++++++ 26 files changed, 833 insertions(+), 3 deletions(-) create mode 100644 Documentation/admin-guide/syscall-user-dispatch.rst create mode 100644 include/linux/syscall_user_dispatch.h create mode 100644 kernel/entry/common.h create mode 100644 kernel/entry/syscall_user_dispatch.c create mode 100644 tools/testing/selftests/syscall_user_dispatch/.gitignore create mode 100644 tools/testing/selftests/syscall_user_dispatch/Makefile create mode 100644 tools/testing/selftests/syscall_user_dispatch/config create mode 100644 tools/testing/selftests/syscall_user_dispatch/sud_benchmark.c create mode 100644 tools/testing/selftests/syscall_user_dispatch/sud_test.c -- 2.29.2

4 years, 1 month

5
18
0 0

[PATCH] selftests/seccomp: sh: Fix register names

by Kees Cook

It looks like the seccomp selftests were never actually built for sh. This fixes it, though I don't have an environment to do a runtime test of it yet. Fixes: 0bb605c2c7f2b4b3 ("sh: Add SECCOMP_FILTER") Signed-off-by: Kees Cook <keescook(a)chromium.org> --- tools/testing/selftests/seccomp/seccomp_bpf.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/tools/testing/selftests/seccomp/seccomp_bpf.c b/tools/testing/selftests/seccomp/seccomp_bpf.c index 7f7ecfcd66db..26c72f2b61b1 100644 --- a/tools/testing/selftests/seccomp/seccomp_bpf.c +++ b/tools/testing/selftests/seccomp/seccomp_bpf.c @@ -1804,8 +1804,8 @@ TEST_F(TRACE_poke, getpid_runs_normally) #define SYSCALL_RET(_regs) (_regs).a[(_regs).windowbase * 4 + 2] #elif defined(__sh__) # define ARCH_REGS struct pt_regs -# define SYSCALL_NUM(_regs) (_regs).gpr[3] -# define SYSCALL_RET(_regs) (_regs).gpr[0] +# define SYSCALL_NUM(_regs) (_regs).regs[3] +# define SYSCALL_RET(_regs) (_regs).regs[0] #else # error "Do not know how to find your architecture's registers and syscalls" #endif -- 2.25.1

4 years, 1 month

2
5
0 0

[PATCH v1 0/9] Landlock fixes

by Mickaël Salaün

Hi, This patch series fixes some issues and makes the Landlock filesystem access-control more consistent and deterministic when stacking multiple rulesets. This is checked by current and new tests. I also extended documentation and example to help users. This series can be applied on top of https://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security.git/… Regards, Mickaël Salaün (9): landlock: Fix memory allocation error handling landlock: Cosmetic fixes for filesystem management landlock: Enforce deterministic interleaved path rules landlock: Always intersect access rights landlock: Add extra checks when inserting a rule selftests/landlock: Extend layout1.inherit_superset landlock: Clean up get_ruleset_from_fd() landlock: Add help to enable Landlock as a stacked LSM landlock: Extend documentation about limitations Documentation/userspace-api/landlock.rst | 17 +++ samples/landlock/sandboxer.c | 21 +++- security/landlock/Kconfig | 4 +- security/landlock/fs.c | 67 +++++----- security/landlock/object.c | 5 +- security/landlock/ruleset.c | 34 ++--- security/landlock/syscall.c | 24 ++-- tools/testing/selftests/landlock/fs_test.c | 140 +++++++++++++++++++-- 8 files changed, 239 insertions(+), 73 deletions(-) base-commit: 96b3198c4025c11347651700b77e45a686d78553 -- 2.29.2

4 years, 1 month

2
11
0 0

[PATCH v2 21/22] x86/fpu/xstate: Support dynamic user state in the signal handling path

by Chang S. Bae

Entering a signal handler, the kernel saves the XSAVE area. The dynamic user state is better to be saved only when used. fpu->state_mask can help to exclude unused states. Returning from a signal handler, XRSTOR re-initializes the excluded state components. Add a test case to verify in the signal handler that the signal frame excludes AMX data when the signaled thread has initialized AMX state. No functional change until the kernel supports the dynamic user states. Signed-off-by: Chang S. Bae <chang.seok.bae(a)intel.com> Reviewed-by: Len Brown <len.brown(a)intel.com> Cc: x86(a)kernel.org Cc: linux-kernel(a)vger.kernel.org Cc: linux-kselftest(a)vger.kernel.org --- Changes from v1: * Made it revertible (moved close to the end of the series) * Included test case --- arch/x86/include/asm/fpu/internal.h | 2 +- tools/testing/selftests/x86/amx.c | 89 +++++++++++++++++++++++++++++ 2 files changed, 90 insertions(+), 1 deletion(-) diff --git a/arch/x86/include/asm/fpu/internal.h b/arch/x86/include/asm/fpu/internal.h index ede3f88bdc52..d8e56e96df49 100644 --- a/arch/x86/include/asm/fpu/internal.h +++ b/arch/x86/include/asm/fpu/internal.h @@ -369,7 +369,7 @@ static inline void copy_kernel_to_xregs(struct xregs_state *xstate, u64 mask) */ static inline int copy_xregs_to_user(struct xregs_state __user *buf) { - u64 mask = xfeatures_mask_user(); + u64 mask = current->thread.fpu.state_mask; u32 lmask = mask; u32 hmask = mask >> 32; int err; diff --git a/tools/testing/selftests/x86/amx.c b/tools/testing/selftests/x86/amx.c index dce3b298f043..bf766b22cf77 100644 --- a/tools/testing/selftests/x86/amx.c +++ b/tools/testing/selftests/x86/amx.c @@ -623,6 +623,94 @@ static void test_ptrace(void) test_tile_state_write(ptracee_loads_tiles); } +/* Signal handling test */ + +static int sigtrapped; +struct tile_data sig_tiles, sighdl_tiles; + +static void sethandler(int sig, void (*handler)(int, siginfo_t *, void *), + int flags) +{ + struct sigaction sa; + + memset(&sa, 0, sizeof(sa)); + sa.sa_sigaction = handler; + sa.sa_flags = SA_SIGINFO | flags; + sigemptyset(&sa.sa_mask); + if (sigaction(sig, &sa, 0)) + err(1, "sigaction"); +} + +static void clearhandler(int sig) +{ + struct sigaction sa; + + memset(&sa, 0, sizeof(sa)); + sa.sa_handler = SIG_DFL; + sigemptyset(&sa.sa_mask); + if (sigaction(sig, &sa, 0)) + err(1, "sigaction"); +} + +static void sighandler(int sig, siginfo_t *info, void *ctx_void) +{ + ucontext_t *uctxt = (ucontext_t *)ctx_void; + struct xsave_data xdata; + struct tile_config cfg; + struct tile_data tiles; + u64 header; + + header = __get_xsave_xstate_bv((void *)uctxt->uc_mcontext.fpregs); + + if (header & (1 << XFEATURE_XTILE_DATA)) + printf("[FAIL]\ttile data was written in sigframe\n"); + else + printf("[OK]\ttile data was skipped in sigframe\n"); + + set_tilecfg(&cfg); + load_tilecfg(&cfg); + init_xdata(&xdata); + + make_tiles(&tiles); + copy_tiles_to_xdata(&xdata, &tiles); + restore_xdata(&xdata); + + save_xdata(&xdata); + if (compare_xdata_tiles(&xdata, &tiles)) + err(1, "tile load file"); + + printf("\tsignal handler: load tile data\n"); + + sigtrapped = sig; +} + +static void test_signal_handling(void) +{ + struct xsave_data xdata = { 0 }; + struct tile_data tiles = { 0 }; + + clearhandler(SIGTRAP); + sethandler(SIGTRAP, sighandler, 1); + sigtrapped = 0; + + printf("[RUN]\tCheck tile state management in handling signal\n"); + + printf("\tbefore signal: initial tile data state\n"); + + raise(SIGTRAP); + + if (sigtrapped == 0) + err(1, "sigtrap"); + + save_xdata(&xdata); + if (compare_xdata_tiles(&xdata, &tiles)) { + printf("[FAIL]\ttile data was not loaded at sigreturn\n"); + nerrs++; + } else { + printf("[OK]\ttile data was re-initialized at sigreturn\n"); + } +} + int main(void) { /* Check hardware availability at first */ @@ -642,6 +730,7 @@ int main(void) test_fork(); test_context_switch(); test_ptrace(); + test_signal_handling(); return nerrs ? 1 : 0; } -- 2.17.1

4 years, 1 month

1
0
0 0

[PATCH v2 20/22] selftest/x86/amx: Include test cases for the AMX state management

by Chang S. Bae

This selftest exercises the kernel's ability to inherit and context switch AMX state, by verifying that they retain unique data when creating a child process and between multiple threads. Also, ptrace() is used to insert AMX state into existing threads -- both before and after the existing thread has initialized its AMX state. Collect the test cases of validating those operations together, as they share some common setup for the AMX state. These test cases do not depend on AMX compiler support, as they employ user-space-XSAVE directly to access AMX state. Signed-off-by: Chang S. Bae <chang.seok.bae(a)intel.com> Reviewed-by: Len Brown <len.brown(a)intel.com> Cc: x86(a)kernel.org Cc: linux-kernel(a)vger.kernel.org Cc: linux-kselftest(a)vger.kernel.org --- Changes from v1: * Removed signal testing code --- tools/testing/selftests/x86/Makefile | 2 +- tools/testing/selftests/x86/amx.c | 647 +++++++++++++++++++++++++++ 2 files changed, 648 insertions(+), 1 deletion(-) create mode 100644 tools/testing/selftests/x86/amx.c diff --git a/tools/testing/selftests/x86/Makefile b/tools/testing/selftests/x86/Makefile index 6703c7906b71..8408bbde788f 100644 --- a/tools/testing/selftests/x86/Makefile +++ b/tools/testing/selftests/x86/Makefile @@ -17,7 +17,7 @@ TARGETS_C_BOTHBITS := single_step_syscall sysret_ss_attrs syscall_nt test_mremap TARGETS_C_32BIT_ONLY := entry_from_vm86 test_syscall_vdso unwind_vdso \ test_FCMOV test_FCOMI test_FISTTP \ vdso_restorer -TARGETS_C_64BIT_ONLY := fsgsbase sysret_rip syscall_numbering +TARGETS_C_64BIT_ONLY := fsgsbase sysret_rip syscall_numbering amx # Some selftests require 32bit support enabled also on 64bit systems TARGETS_C_32BIT_NEEDED := ldt_gdt ptrace_syscall diff --git a/tools/testing/selftests/x86/amx.c b/tools/testing/selftests/x86/amx.c new file mode 100644 index 000000000000..dce3b298f043 --- /dev/null +++ b/tools/testing/selftests/x86/amx.c @@ -0,0 +1,647 @@ +// SPDX-License-Identifier: GPL-2.0 + +#define _GNU_SOURCE +#include <err.h> +#include <elf.h> +#include <pthread.h> +#include <sched.h> +#include <signal.h> +#include <stdio.h> +#include <string.h> +#include <stdbool.h> +#include <stdint.h> +#include <stdlib.h> +#include <time.h> +#include <malloc.h> +#include <unistd.h> +#include <ucontext.h> + +#include <linux/futex.h> + +#include <sys/ipc.h> +#include <sys/mman.h> +#include <sys/ptrace.h> +#include <sys/shm.h> +#include <sys/signal.h> +#include <sys/syscall.h> +#include <sys/time.h> +#include <sys/types.h> +#include <sys/wait.h> +#include <sys/uio.h> +#include <sys/ucontext.h> + +#include <x86intrin.h> + +#ifndef __x86_64__ +# error This test is 64-bit only +#endif + +typedef uint8_t u8; +typedef uint16_t u16; +typedef uint32_t u32; +typedef uint64_t u64; + +#define PAGE_SIZE (1 << 12) + +#define NUM_TILES 8 +#define TILE_SIZE 1024 +#define XSAVE_SIZE ((NUM_TILES * TILE_SIZE) + PAGE_SIZE) + +struct xsave_data { + u8 area[XSAVE_SIZE]; +} __attribute__((aligned(64))); + +/* Tile configuration associated: */ +#define MAX_TILES 16 +#define RESERVED_BYTES 14 + +struct tile_config { + u8 palette_id; + u8 start_row; + u8 reserved[RESERVED_BYTES]; + u16 colsb[MAX_TILES]; + u8 rows[MAX_TILES]; +}; + +struct tile_data { + u8 data[NUM_TILES * TILE_SIZE]; +}; + +static inline u64 __xgetbv(u32 index) +{ + u32 eax, edx; + + asm volatile(".byte 0x0f,0x01,0xd0" + : "=a" (eax), "=d" (edx) + : "c" (index)); + return eax + ((u64)edx << 32); +} + +static inline void __cpuid(u32 *eax, u32 *ebx, u32 *ecx, u32 *edx) +{ + asm volatile("cpuid;" + : "=a" (*eax), "=b" (*ebx), "=c" (*ecx), "=d" (*edx) + : "0" (*eax), "2" (*ecx)); +} + +/* Load tile configuration */ +static inline void __ldtilecfg(void *cfg) +{ + asm volatile(".byte 0xc4,0xe2,0x78,0x49,0x00" + : : "a"(cfg)); +} + +/* Load tile data to %tmm0 register only */ +static inline void __tileloadd(void *tile) +{ + asm volatile(".byte 0xc4,0xe2,0x7b,0x4b,0x04,0x10" + : : "a"(tile), "d"(0)); +} + +/* Save extended states */ +static inline void __xsave(void *area, u32 lo, u32 hi) +{ + asm volatile(".byte 0x48,0x0f,0xae,0x27" + : : "D" (area), "a" (lo), "d" (hi) + : "memory"); +} + +/* Restore extended states */ +static inline void __xrstor(void *area, u32 lo, u32 hi) +{ + asm volatile(".byte 0x48,0x0f,0xae,0x2f" + : : "D" (area), "a" (lo), "d" (hi)); +} + +/* Release tile states to init values */ +static inline void __tilerelease(void) +{ + asm volatile(".byte 0xc4, 0xe2, 0x78, 0x49, 0xc0" ::); +} + +/* Hardware info check: */ + +static inline bool check_xsave_supports_xtile(void) +{ + u32 eax, ebx, ecx, edx; + bool available = false; + +#define XSAVE_CPUID 0x1 +#define XSAVE_ECX_BIT 26 +#define XFEATURE_XTILE_CFG 17 +#define XFEATURE_XTILE_DATA 18 +#define XFEATURE_MASK_XTILE ((1 << XFEATURE_XTILE_DATA) | \ + (1 << XFEATURE_XTILE_CFG)) + + eax = XSAVE_CPUID; + ecx = 0; + + __cpuid(&eax, &ebx, &ecx, &edx); + if (!(ecx & (1 << XSAVE_ECX_BIT))) + return available; + + if (__xgetbv(0) & XFEATURE_MASK_XTILE) + available = true; + + return available; +} + +struct xtile_hwinfo { + struct { + u16 bytes_per_tile; + u16 bytes_per_row; + u16 max_names; + u16 max_rows; + } spec; + + struct { + u32 offset; + u32 size; + } xsave; +}; + +static struct xtile_hwinfo xtile; + +static bool __enum_xtile_config(void) +{ + u32 eax, ebx, ecx, edx; + u16 bytes_per_tile; + bool valid = false; + +#define TILE_CPUID 0x1d +#define TILE_PALETTE_CPUID_SUBLEAVE 0x1 + + eax = TILE_CPUID; + ecx = TILE_PALETTE_CPUID_SUBLEAVE; + + __cpuid(&eax, &ebx, &ecx, &edx); + if (!eax || !ebx || !ecx) + return valid; + + xtile.spec.max_names = ebx >> 16; + if (xtile.spec.max_names < NUM_TILES) + return valid; + + bytes_per_tile = eax >> 16; + if (bytes_per_tile < TILE_SIZE) + return valid; + + xtile.spec.bytes_per_row = ebx; + xtile.spec.max_rows = ecx; + valid = true; + + return valid; +} + +static bool __enum_xsave_tile(void) +{ + u32 eax, ebx, ecx, edx; + bool valid = false; + +#define XSTATE_CPUID 0xd +#define XSTATE_USER_STATE_SUBLEAVE 0x0 + + eax = XSTATE_CPUID; + ecx = XFEATURE_XTILE_DATA; + + __cpuid(&eax, &ebx, &ecx, &edx); + if (!eax || !ebx) + return valid; + + xtile.xsave.offset = ebx; + xtile.xsave.size = eax; + valid = true; + + return valid; +} + +static bool __check_xsave_size(void) +{ + u32 eax, ebx, ecx, edx; + bool valid = false; + + eax = XSTATE_CPUID; + ecx = XSTATE_USER_STATE_SUBLEAVE; + + __cpuid(&eax, &ebx, &ecx, &edx); + if (ebx && ebx <= XSAVE_SIZE) + valid = true; + + return valid; +} + +/* + * Check the hardware-provided tile state info and cross-check it with the + * hard-coded values: XSAVE_SIZE, NUM_TILES, and TILE_SIZE. + */ +static int check_xtile_hwinfo(void) +{ + bool success = false; + + if (!__check_xsave_size()) + return success; + + if (!__enum_xsave_tile()) + return success; + + if (!__enum_xtile_config()) + return success; + + if (sizeof(struct tile_data) >= xtile.xsave.size) + success = true; + + return success; +} + +/* The helpers for managing XSAVE area and tile states: */ + +/* Use the uncompacted format without 'init optimization' */ +static void save_xdata(void *data) +{ + __xsave(data, -1, -1); +} + +static void restore_xdata(void *data) +{ + __xrstor(data, -1, -1); +} + +static inline u64 __get_xsave_xstate_bv(void *data) +{ +#define XSAVE_HDR_OFFSET 512 + return *(u64 *)(data + XSAVE_HDR_OFFSET); +} + +static void set_tilecfg(struct tile_config *cfg) +{ + int i; + + memset(cfg, 0, sizeof(*cfg)); + /* The first implementation has one significant palette with id 1 */ + cfg->palette_id = 1; + for (i = 0; i < xtile.spec.max_names; i++) { + cfg->colsb[i] = xtile.spec.bytes_per_row; + cfg->rows[i] = xtile.spec.max_rows; + } +} + +static void load_tilecfg(struct tile_config *cfg) +{ + __ldtilecfg(cfg); +} + +static void make_tiles(void *tiles) +{ + u32 iterations = xtile.xsave.size / sizeof(u32); + static u32 value = 1; + u32 *ptr = tiles; + int i; + + for (i = 0, ptr = tiles; i < iterations; i++, ptr++) + *ptr = value; + value++; +} + +/* + * Initialize the XSAVE area: + * + * Make sure tile configuration loaded already. Load limited tile data (%tmm0 only) + * and save all the states. XSAVE area is ready to complete tile data. + */ +static void init_xdata(void *data) +{ + struct tile_data tiles; + + make_tiles(&tiles); + __tileloadd(&tiles); + __xsave(data, -1, -1); +} + +static inline void *__get_xsave_tile_data_addr(void *data) +{ + return data + xtile.xsave.offset; +} + +static void copy_tiles_to_xdata(void *xdata, void *tiles) +{ + void *dst = __get_xsave_tile_data_addr(xdata); + + memcpy(dst, tiles, xtile.xsave.size); +} + +static int compare_xdata_tiles(void *xdata, void *tiles) +{ + void *tile_data = __get_xsave_tile_data_addr(xdata); + + if (memcmp(tile_data, tiles, xtile.xsave.size)) + return 1; + + return 0; +} + +static int nerrs, errs; + +/* Testing tile data inheritance */ + +static void test_tile_data_inheritance(void) +{ + struct xsave_data xdata; + struct tile_data tiles; + struct tile_config cfg; + pid_t child; + int status; + + set_tilecfg(&cfg); + load_tilecfg(&cfg); + init_xdata(&xdata); + + make_tiles(&tiles); + copy_tiles_to_xdata(&xdata, &tiles); + restore_xdata(&xdata); + + errs = 0; + + child = fork(); + if (child < 0) + err(1, "fork"); + + if (child == 0) { + memset(&xdata, 0, sizeof(xdata)); + save_xdata(&xdata); + if (compare_xdata_tiles(&xdata, &tiles)) { + printf("[FAIL]\tchild failed to inherit tile data during fork()\n"); + nerrs++; + } else { + printf("[OK]\tchild inherited tile data during fork()\n"); + } + _exit(0); + } + wait(&status); +} + +static void test_fork(void) +{ + pid_t child; + int status; + + child = fork(); + if (child < 0) + err(1, "fork"); + + if (child == 0) { + test_tile_data_inheritance(); + _exit(0); + } + + wait(&status); +} + +/* Context switching test */ + +#define ITERATIONS 10 +#define NUM_THREADS 5 + +struct futex_info { + int current; + int next; + int *futex; +}; + +static inline void command_wait(struct futex_info *info, int value) +{ + do { + sched_yield(); + } while (syscall(SYS_futex, info->futex, FUTEX_WAIT, value, 0, 0, 0)); +} + +static inline void command_wake(struct futex_info *info, int value) +{ + do { + *info->futex = value; + while (!syscall(SYS_futex, info->futex, FUTEX_WAKE, 1, 0, 0, 0)) + sched_yield(); + } while (0); +} + +static inline int get_iterative_value(int id) +{ + return ((id << 1) & ~0x1); +} + +static inline int get_endpoint_value(int id) +{ + return ((id << 1) | 0x1); +} + +static void *check_tiles(void *info) +{ + struct futex_info *finfo = (struct futex_info *)info; + struct xsave_data xdata; + struct tile_data tiles; + struct tile_config cfg; + int i; + + set_tilecfg(&cfg); + load_tilecfg(&cfg); + init_xdata(&xdata); + + make_tiles(&tiles); + copy_tiles_to_xdata(&xdata, &tiles); + restore_xdata(&xdata); + + for (i = 0; i < ITERATIONS; i++) { + command_wait(finfo, get_iterative_value(finfo->current)); + + memset(&xdata, 0, sizeof(xdata)); + save_xdata(&xdata); + errs += compare_xdata_tiles(&xdata, &tiles); + + make_tiles(&tiles); + copy_tiles_to_xdata(&xdata, &tiles); + restore_xdata(&xdata); + + command_wake(finfo, get_iterative_value(finfo->next)); + } + + command_wait(finfo, get_endpoint_value(finfo->current)); + __tilerelease(); + return NULL; +} + +static int create_children(int num, struct futex_info *finfo) +{ + const int shm_id = shmget(IPC_PRIVATE, sizeof(int), IPC_CREAT | 0666); + int *futex = shmat(shm_id, NULL, 0); + pthread_t thread; + int i; + + for (i = 0; i < num; i++) { + finfo[i].futex = futex; + finfo[i].current = i + 1; + finfo[i].next = (i + 2) % (num + 1); + + if (pthread_create(&thread, NULL, check_tiles, &finfo[i])) { + err(1, "pthread_create"); + return 1; + } + } + return 0; +} + +static void test_context_switch(void) +{ + struct futex_info *finfo; + cpu_set_t cpuset; + int i; + + printf("[RUN]\t%u context switches of tile states in %d threads\n", + ITERATIONS * NUM_THREADS, NUM_THREADS); + + errs = 0; + + CPU_ZERO(&cpuset); + CPU_SET(0, &cpuset); + if (sched_setaffinity(0, sizeof(cpuset), &cpuset) != 0) + err(1, "sched_setaffinity to CPU 0"); + + finfo = malloc(sizeof(*finfo) * NUM_THREADS); + + if (create_children(NUM_THREADS, finfo)) + return; + + for (i = 0; i < ITERATIONS; i++) { + command_wake(finfo, get_iterative_value(1)); + command_wait(finfo, get_iterative_value(0)); + } + + for (i = 1; i <= NUM_THREADS; i++) + command_wake(finfo, get_endpoint_value(i)); + + if (errs) { + printf("[FAIL]\t%u incorrect tile states\n", errs); + nerrs += errs; + return; + } + + printf("[OK]\tall tile states are correct\n"); +} + +/* Ptrace test */ + +static inline long get_tile_state(pid_t child, struct iovec *iov) +{ + return ptrace(PTRACE_GETREGSET, child, (u32)NT_X86_XSTATE, iov); +} + +static inline long set_tile_state(pid_t child, struct iovec *iov) +{ + return ptrace(PTRACE_SETREGSET, child, (u32)NT_X86_XSTATE, iov); +} + +static int write_tile_state(bool load_tile, pid_t child) +{ + struct xsave_data xdata; + struct tile_data tiles; + struct iovec iov; + + iov.iov_base = &xdata; + iov.iov_len = sizeof(xdata); + + if (get_tile_state(child, &iov)) + err(1, "PTRACE_GETREGSET"); + + make_tiles(&tiles); + copy_tiles_to_xdata(&xdata, &tiles); + if (set_tile_state(child, &iov)) + err(1, "PTRACE_SETREGSET"); + + memset(&xdata, 0, sizeof(xdata)); + if (get_tile_state(child, &iov)) + err(1, "PTRACE_GETREGSET"); + + if (!load_tile) + memset(&tiles, 0, sizeof(tiles)); + + return compare_xdata_tiles(&xdata, &tiles); +} + +static void test_tile_state_write(bool load_tile) +{ + pid_t child; + int status; + + child = fork(); + if (child < 0) + err(1, "fork"); + + if (child == 0) { + printf("[RUN]\tPtrace-induced tile state write, "); + printf("%s tile data loaded\n", load_tile ? "with" : "without"); + + if (ptrace(PTRACE_TRACEME, 0, NULL, NULL)) + err(1, "PTRACE_TRACEME"); + + if (load_tile) { + struct tile_config cfg; + struct tile_data tiles; + + set_tilecfg(&cfg); + load_tilecfg(&cfg); + make_tiles(&tiles); + /* Load only %tmm0 but inducing the #NM */ + __tileloadd(&tiles); + } + + raise(SIGTRAP); + _exit(0); + } + + do { + wait(&status); + } while (WSTOPSIG(status) != SIGTRAP); + + errs = write_tile_state(load_tile, child); + if (errs) { + nerrs++; + printf("[FAIL]\t%s write\n", load_tile ? "incorrect" : "unexpected"); + } else { + printf("[OK]\t%s write\n", load_tile ? "correct" : "no"); + } + + ptrace(PTRACE_DETACH, child, NULL, NULL); + wait(&status); +} + +static void test_ptrace(void) +{ + bool ptracee_loads_tiles; + + ptracee_loads_tiles = true; + test_tile_state_write(ptracee_loads_tiles); + + ptracee_loads_tiles = false; + test_tile_state_write(ptracee_loads_tiles); +} + +int main(void) +{ + /* Check hardware availability at first */ + + if (!check_xsave_supports_xtile()) { + printf("\tTile state is not supported in the XSAVE.\n"); + return 0; + } + + if (!check_xtile_hwinfo()) { + printf("\tAvailable tile state size is insufficient to test.\n"); + return 0; + } + + nerrs = 0; + + test_fork(); + test_context_switch(); + test_ptrace(); + + return nerrs ? 1 : 0; +} -- 2.17.1

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Linux-kselftest-mirror November 2020