October 2023 - Linux-kselftest-mirror

[PATCH v33 0/6] Implement IOCTL to get and optionally clear info about PTEs

by Muhammad Usama Anjum

*Changes in v33*: - Add PAGE_IS_FILE support for THPs *Changes in v31 and v32*: - Minor updates *Changes in v30*: - Rebase on top of next-20230815 - Minor nitpicks *Changes in v29:* - Polish IOCTL and improve documentation *Changes in v28:* - Fix walk_end and add 17 test cases in selftests patch *Changes in v27:* - Handle review comments and minor improvements - Add performance improvement patch on top with test for easy review *Changes in v26:* - Code re-structurring and API changes in PAGEMAP_IOCTL *Changes in v25*: - Do proper filtering on hole as well (hole got missed earlier) *Changes in v24*: - Rebase on top of next-20230710 - Place WP markers in case of hole as well *Changes in v23*: - Set vec_buf_index in loop only when vec_buf_index is set - Return -EFAULT instead of -EINVAL if vec is NULL - Correctly return the walk ending address to the page granularity *Changes in v22*: - Interface change: - Replace [start start + len) with [start, end) - Return the ending address of the address walk in start *Changes in v21*: - Abort walk instead of returning error if WP is to be performed on partial hugetlb *Changes in v20* - Correct PAGE_IS_FILE and add PAGE_IS_PFNZERO *Changes in v19* - Minor changes and interface updates *Changes in v18* - Rebase on top of next-20230613 - Minor updates *Changes in v17* - Rebase on top of next-20230606 - Minor improvements in PAGEMAP_SCAN IOCTL patch *Changes in v16* - Fix a corner case - Add exclusive PM_SCAN_OP_WP back *Changes in v15* - Build fix (Add missed build fix in RESEND) *Changes in v14* - Fix build error caused by #ifdef added at last minute in some configs *Changes in v13* - Rebase on top of next-20230414 - Give-up on using uffd_wp_range() and write new helpers, flush tlb only once *Changes in v12* - Update and other memory types to UFFD_FEATURE_WP_ASYNC - Rebaase on top of next-20230406 - Review updates *Changes in v11* - Rebase on top of next-20230307 - Base patches on UFFD_FEATURE_WP_UNPOPULATED - Do a lot of cosmetic changes and review updates - Remove ENGAGE_WP + !GET operation as it can be performed with UFFDIO_WRITEPROTECT *Changes in v10* - Add specific condition to return error if hugetlb is used with wp async - Move changes in tools/include/uapi/linux/fs.h to separate patch - Add documentation *Changes in v9:* - Correct fault resolution for userfaultfd wp async - Fix build warnings and errors which were happening on some configs - Simplify pagemap ioctl's code *Changes in v8:* - Update uffd async wp implementation - Improve PAGEMAP_IOCTL implementation *Changes in v7:* - Add uffd wp async - Update the IOCTL to use uffd under the hood instead of soft-dirty flags *Motivation* The real motivation for adding PAGEMAP_SCAN IOCTL is to emulate Windows GetWriteWatch() and ResetWriteWatch() syscalls [1]. The GetWriteWatch() retrieves the addresses of the pages that are written to in a region of virtual memory. This syscall is used in Windows applications and games etc. This syscall is being emulated in pretty slow manner in userspace. Our purpose is to enhance the kernel such that we translate it efficiently in a better way. Currently some out of tree hack patches are being used to efficiently emulate it in some kernels. We intend to replace those with these patches. So the whole gaming on Linux can effectively get benefit from this. It means there would be tons of users of this code. CRIU use case [2] was mentioned by Andrei and Danylo: > Use cases for migrating sparse VMAs are binaries sanitized with ASAN, > MSAN or TSAN [3]. All of these sanitizers produce sparse mappings of > shadow memory [4]. Being able to migrate such binaries allows to highly > reduce the amount of work needed to identify and fix post-migration > crashes, which happen constantly. Andrei's defines the following uses of this code: * it is more granular and allows us to track changed pages more effectively. The current interface can clear dirty bits for the entire process only. In addition, reading info about pages is a separate operation. It means we must freeze the process to read information about all its pages, reset dirty bits, only then we can start dumping pages. The information about pages becomes more and more outdated, while we are processing pages. The new interface solves both these downsides. First, it allows us to read pte bits and clear the soft-dirty bit atomically. It means that CRIU will not need to freeze processes to pre-dump their memory. Second, it clears soft-dirty bits for a specified region of memory. It means CRIU will have actual info about pages to the moment of dumping them. * The new interface has to be much faster because basic page filtering is happening in the kernel. With the old interface, we have to read pagemap for each page. *Implementation Evolution (Short Summary)* From the definition of GetWriteWatch(), we feel like kernel's soft-dirty feature can be used under the hood with some additions like: * reset soft-dirty flag for only a specific region of memory instead of clearing the flag for the entire process * get and clear soft-dirty flag for a specific region atomically So we decided to use ioctl on pagemap file to read or/and reset soft-dirty flag. But using soft-dirty flag, sometimes we get extra pages which weren't even written. They had become soft-dirty because of VMA merging and VM_SOFTDIRTY flag. This breaks the definition of GetWriteWatch(). We were able to by-pass this short coming by ignoring VM_SOFTDIRTY until David reported that mprotect etc messes up the soft-dirty flag while ignoring VM_SOFTDIRTY [5]. This wasn't happening until [6] got introduced. We discussed if we can revert these patches. But we could not reach to any conclusion. So at this point, I made couple of tries to solve this whole VM_SOFTDIRTY issue by correcting the soft-dirty implementation: * [7] Correct the bug fixed wrongly back in 2014. It had potential to cause regression. We left it behind. * [8] Keep a list of soft-dirty part of a VMA across splits and merges. I got the reply don't increase the size of the VMA by 8 bytes. At this point, we left soft-dirty considering it is too much delicate and userfaultfd [9] seemed like the only way forward. From there onward, we have been basing soft-dirty emulation on userfaultfd wp feature where kernel resolves the faults itself when WP_ASYNC feature is used. It was straight forward to add WP_ASYNC feature in userfautlfd. Now we get only those pages dirty or written-to which are really written in reality. (PS There is another WP_UNPOPULATED userfautfd feature is required which is needed to avoid pre-faulting memory before write-protecting [9].) All the different masks were added on the request of CRIU devs to create interface more generic and better. [1] https://learn.microsoft.com/en-us/windows/win32/api/memoryapi/nf-memoryapi-… [2] https://lore.kernel.org/all/20221014134802.1361436-1-mdanylo@google.com [3] https://github.com/google/sanitizers [4] https://github.com/google/sanitizers/wiki/AddressSanitizerAlgorithm#64-bit [5] https://lore.kernel.org/all/bfcae708-db21-04b4-0bbe-712badd03071@redhat.com [6] https://lore.kernel.org/all/20220725142048.30450-1-peterx@redhat.com/ [7] https://lore.kernel.org/all/20221122115007.2787017-1-usama.anjum@collabora.… [8] https://lore.kernel.org/all/20221220162606.1595355-1-usama.anjum@collabora.… [9] https://lore.kernel.org/all/20230306213925.617814-1-peterx@redhat.com [10] https://lore.kernel.org/all/20230125144529.1630917-1-mdanylo@google.com * Original Cover letter from v8* Hello, Note: Soft-dirty pages and pages which have been written-to are synonyms. As kernel already has soft-dirty feature inside which we have given up to use, we are using written-to terminology while using UFFD async WP under the hood. It is possible to find and clear soft-dirty pages entirely in userspace. But it isn't efficient: - The mprotect and SIGSEGV handler for bookkeeping - The userfaultfd wp (synchronous) with the handler for bookkeeping Some benchmarks can be seen here[1]. This series adds features that weren't present earlier: - There is no atomic get soft-dirty/Written-to status and clear present in the kernel. - The pages which have been written-to can not be found in accurate way. (Kernel's soft-dirty PTE bit + sof_dirty VMA bit shows more soft-dirty pages than there actually are.) Historically, soft-dirty PTE bit tracking has been used in the CRIU project. The procfs interface is enough for finding the soft-dirty bit status and clearing the soft-dirty bit of all the pages of a process. We have the use case where we need to track the soft-dirty PTE bit for only specific pages on-demand. We need this tracking and clear mechanism of a region of memory while the process is running to emulate the getWriteWatch() syscall of Windows. *(Moved to using UFFD instead of soft-dirty feature to find pages which have been written-to from v7 patch series)*: Stop using the soft-dirty flags for finding which pages have been written to. It is too delicate and wrong as it shows more soft-dirty pages than the actual soft-dirty pages. There is no interest in correcting it [2][3] as this is how the feature was written years ago. It shouldn't be updated to changed behaviour. Peter Xu has suggested using the async version of the UFFD WP [4] as it is based inherently on the PTEs. So in this patch series, I've added a new mode to the UFFD which is asynchronous version of the write protect. When this variant of the UFFD WP is used, the page faults are resolved automatically by the kernel. The pages which have been written-to can be found by reading pagemap file (!PM_UFFD_WP). This feature can be used successfully to find which pages have been written to from the time the pages were write protected. This works just like the soft-dirty flag without showing any extra pages which aren't soft-dirty in reality. The information related to pages if the page is file mapped, present and swapped is required for the CRIU project [5][6]. The addition of the required mask, any mask, excluded mask and return masks are also required for the CRIU project [5]. The IOCTL returns the addresses of the pages which match the specific masks. The page addresses are returned in struct page_region in a compact form. The max_pages is needed to support a use case where user only wants to get a specific number of pages. So there is no need to find all the pages of interest in the range when max_pages is specified. The IOCTL returns when the maximum number of the pages are found. The max_pages is optional. If max_pages is specified, it must be equal or greater than the vec_size. This restriction is needed to handle worse case when one page_region only contains info of one page and it cannot be compacted. This is needed to emulate the Windows getWriteWatch() syscall. The patch series include the detailed selftest which can be used as an example for the uffd async wp test and PAGEMAP_IOCTL. It shows the interface usages as well. [1] https://lore.kernel.org/lkml/54d4c322-cd6e-eefd-b161-2af2b56aae24@collabora… [2] https://lore.kernel.org/all/20221220162606.1595355-1-usama.anjum@collabora.… [3] https://lore.kernel.org/all/20221122115007.2787017-1-usama.anjum@collabora.… [4] https://lore.kernel.org/all/Y6Hc2d+7eTKs7AiH@x1n [5] https://lore.kernel.org/all/YyiDg79flhWoMDZB@gmail.com/ [6] https://lore.kernel.org/all/20221014134802.1361436-1-mdanylo@google.com/ Regards, Muhammad Usama Anjum Muhammad Usama Anjum (5): fs/proc/task_mmu: Implement IOCTL to get and optionally clear info about PTEs fs/proc/task_mmu: Add fast paths to get/clear PAGE_IS_WRITTEN flag tools headers UAPI: Update linux/fs.h with the kernel sources mm/pagemap: add documentation of PAGEMAP_SCAN IOCTL selftests: mm: add pagemap ioctl tests Peter Xu (1): userfaultfd: UFFD_FEATURE_WP_ASYNC Documentation/admin-guide/mm/pagemap.rst | 89 + Documentation/admin-guide/mm/userfaultfd.rst | 35 + fs/proc/task_mmu.c | 722 ++++++++ fs/userfaultfd.c | 26 +- include/linux/hugetlb.h | 1 + include/linux/userfaultfd_k.h | 28 +- include/uapi/linux/fs.h | 59 + include/uapi/linux/userfaultfd.h | 9 +- mm/hugetlb.c | 34 +- mm/memory.c | 28 +- tools/include/uapi/linux/fs.h | 59 + tools/testing/selftests/mm/.gitignore | 2 + tools/testing/selftests/mm/Makefile | 3 +- tools/testing/selftests/mm/config | 1 + tools/testing/selftests/mm/pagemap_ioctl.c | 1660 ++++++++++++++++++ tools/testing/selftests/mm/run_vmtests.sh | 4 + 16 files changed, 2736 insertions(+), 24 deletions(-) create mode 100644 tools/testing/selftests/mm/pagemap_ioctl.c -- 2.40.1

6 months, 2 weeks

3
12
0 0

[PATCH bpf-next v3 1/2] selftests/bpf: Convert CHECK macros to ASSERT_* macros in bpf_iter

by Yuran Pereira

As it was pointed out by Yonghong Song [1], in the bpf selftests the use of the ASSERT_* series of macros is preferred over the CHECK macro. This patch replaces all CHECK calls in bpf_iter with the appropriate ASSERT_* macros. [1] https://lore.kernel.org/lkml/0a142924-633c-44e6-9a92-2dc019656bf2@linux.dev Suggested-by: Yonghong Song <yonghong.song(a)linux.dev> Signed-off-by: Yuran Pereira <yuran.pereira(a)hotmail.com> --- .../selftests/bpf/prog_tests/bpf_iter.c | 79 ++++++++----------- 1 file changed, 35 insertions(+), 44 deletions(-) diff --git a/tools/testing/selftests/bpf/prog_tests/bpf_iter.c b/tools/testing/selftests/bpf/prog_tests/bpf_iter.c index 1f02168103dd..123a3502b8f0 100644 --- a/tools/testing/selftests/bpf/prog_tests/bpf_iter.c +++ b/tools/testing/selftests/bpf/prog_tests/bpf_iter.c @@ -34,8 +34,6 @@ #include "bpf_iter_ksym.skel.h" #include "bpf_iter_sockmap.skel.h" -static int duration; - static void test_btf_id_or_null(void) { struct bpf_iter_test_kern3 *skel; @@ -64,7 +62,7 @@ static void do_dummy_read_opts(struct bpf_program *prog, struct bpf_iter_attach_ /* not check contents, but ensure read() ends without error */ while ((len = read(iter_fd, buf, sizeof(buf))) > 0) ; - CHECK(len < 0, "read", "read failed: %s\n", strerror(errno)); + ASSERT_GE(len, 0, "read"); close(iter_fd); @@ -413,7 +411,7 @@ static int do_btf_read(struct bpf_iter_task_btf *skel) goto free_link; } - if (CHECK(err < 0, "read", "read failed: %s\n", strerror(errno))) + if (!ASSERT_GE(err, 0, "read")) goto free_link; ASSERT_HAS_SUBSTR(taskbuf, "(struct task_struct)", @@ -526,11 +524,11 @@ static int do_read_with_fd(int iter_fd, const char *expected, start = 0; while ((len = read(iter_fd, buf + start, read_buf_len)) > 0) { start += len; - if (CHECK(start >= 16, "read", "read len %d\n", len)) + if (!ASSERT_LT(start, 16, "read")) return -1; read_buf_len = read_one_char ? 1 : 16 - start; } - if (CHECK(len < 0, "read", "read failed: %s\n", strerror(errno))) + if (!ASSERT_GE(len, 0, "read")) return -1; if (!ASSERT_STREQ(buf, expected, "read")) @@ -571,8 +569,7 @@ static int do_read(const char *path, const char *expected) int err, iter_fd; iter_fd = open(path, O_RDONLY); - if (CHECK(iter_fd < 0, "open", "open %s failed: %s\n", - path, strerror(errno))) + if (!ASSERT_GE(iter_fd, 0, "open")) return -1; err = do_read_with_fd(iter_fd, expected, false); @@ -600,7 +597,7 @@ static void test_file_iter(void) unlink(path); err = bpf_link__pin(link, path); - if (CHECK(err, "pin_iter", "pin_iter to %s failed: %d\n", path, err)) + if (!ASSERT_OK(err, "pin_iter")) goto free_link; err = do_read(path, "abcd"); @@ -651,12 +648,10 @@ static void test_overflow(bool test_e2big_overflow, bool ret1) * overflow and needs restart. */ map1_fd = bpf_map_create(BPF_MAP_TYPE_ARRAY, NULL, 4, 8, 1, NULL); - if (CHECK(map1_fd < 0, "bpf_map_create", - "map_creation failed: %s\n", strerror(errno))) + if (!ASSERT_GE(map1_fd, 0, "bpf_map_create")) goto out; map2_fd = bpf_map_create(BPF_MAP_TYPE_ARRAY, NULL, 4, 8, 1, NULL); - if (CHECK(map2_fd < 0, "bpf_map_create", - "map_creation failed: %s\n", strerror(errno))) + if (!ASSERT_GE(map2_fd, 0, "bpf_map_create")) goto free_map1; /* bpf_seq_printf kernel buffer is 8 pages, so one map @@ -685,14 +680,12 @@ static void test_overflow(bool test_e2big_overflow, bool ret1) /* setup filtering map_id in bpf program */ map_info_len = sizeof(map_info); err = bpf_map_get_info_by_fd(map1_fd, &map_info, &map_info_len); - if (CHECK(err, "get_map_info", "get map info failed: %s\n", - strerror(errno))) + if (!ASSERT_OK(err, "get_map_info")) goto free_map2; skel->bss->map1_id = map_info.id; err = bpf_map_get_info_by_fd(map2_fd, &map_info, &map_info_len); - if (CHECK(err, "get_map_info", "get map info failed: %s\n", - strerror(errno))) + if (!ASSERT_OK(err, "get_map_info")) goto free_map2; skel->bss->map2_id = map_info.id; @@ -714,16 +707,14 @@ static void test_overflow(bool test_e2big_overflow, bool ret1) while ((len = read(iter_fd, buf, expected_read_len)) > 0) total_read_len += len; - CHECK(len != -1 || errno != E2BIG, "read", - "expected ret -1, errno E2BIG, but get ret %d, error %s\n", - len, strerror(errno)); + ASSERT_EQ(len, -1, "read"); + ASSERT_EQ(errno, E2BIG, "read"); goto free_buf; } else if (!ret1) { while ((len = read(iter_fd, buf, expected_read_len)) > 0) total_read_len += len; - if (CHECK(len < 0, "read", "read failed: %s\n", - strerror(errno))) + if (!ASSERT_GE(len, 0, "read")) goto free_buf; } else { do { @@ -732,8 +723,7 @@ static void test_overflow(bool test_e2big_overflow, bool ret1) total_read_len += len; } while (len > 0 || len == -EAGAIN); - if (CHECK(len < 0, "read", "read failed: %s\n", - strerror(errno))) + if (!ASSERT_GE(len, 0, "read")) goto free_buf; } @@ -836,7 +826,7 @@ static void test_bpf_hash_map(void) /* do some tests */ while ((len = read(iter_fd, buf, sizeof(buf))) > 0) ; - if (CHECK(len < 0, "read", "read failed: %s\n", strerror(errno))) + if (!ASSERT_GE(len, 0, "read")) goto close_iter; /* test results */ @@ -917,7 +907,7 @@ static void test_bpf_percpu_hash_map(void) /* do some tests */ while ((len = read(iter_fd, buf, sizeof(buf))) > 0) ; - if (CHECK(len < 0, "read", "read failed: %s\n", strerror(errno))) + if (!ASSERT_GE(len, 0, "read")) goto close_iter; /* test results */ @@ -983,17 +973,14 @@ static void test_bpf_array_map(void) start = 0; while ((len = read(iter_fd, buf + start, sizeof(buf) - start)) > 0) start += len; - if (CHECK(len < 0, "read", "read failed: %s\n", strerror(errno))) + if (!ASSERT_GE(len, 0, "read")) goto close_iter; /* test results */ res_first_key = *(__u32 *)buf; res_first_val = *(__u64 *)(buf + sizeof(__u32)); - if (CHECK(res_first_key != 0 || res_first_val != first_val, - "bpf_seq_write", - "seq_write failure: first key %u vs expected 0, " - " first value %llu vs expected %llu\n", - res_first_key, res_first_val, first_val)) + if (!ASSERT_EQ(res_first_key, 0, "bpf_seq_write") || + !ASSERT_EQ(res_first_val, first_val, "bpf_seq_write")) goto close_iter; if (!ASSERT_EQ(skel->bss->key_sum, expected_key, "key_sum")) @@ -1092,7 +1079,7 @@ static void test_bpf_percpu_array_map(void) /* do some tests */ while ((len = read(iter_fd, buf, sizeof(buf))) > 0) ; - if (CHECK(len < 0, "read", "read failed: %s\n", strerror(errno))) + if (!ASSERT_GE(len, 0, "read")) goto close_iter; /* test results */ @@ -1131,6 +1118,7 @@ static void test_bpf_sk_storage_delete(void) sock_fd = socket(AF_INET6, SOCK_STREAM, 0); if (!ASSERT_GE(sock_fd, 0, "socket")) goto out; + err = bpf_map_update_elem(map_fd, &sock_fd, &val, BPF_NOEXIST); if (!ASSERT_OK(err, "map_update")) goto out; @@ -1151,14 +1139,19 @@ static void test_bpf_sk_storage_delete(void) /* do some tests */ while ((len = read(iter_fd, buf, sizeof(buf))) > 0) ; - if (CHECK(len < 0, "read", "read failed: %s\n", strerror(errno))) + if (!ASSERT_GE(len, 0, "read")) goto close_iter; /* test results */ err = bpf_map_lookup_elem(map_fd, &sock_fd, &val); - if (CHECK(!err || errno != ENOENT, "bpf_map_lookup_elem", - "map value wasn't deleted (err=%d, errno=%d)\n", err, errno)) - goto close_iter; + + /* Note: The following assertions serve to ensure + * the value was deleted. It does so by asserting + * that bpf_map_lookup_elem has failed. This might + * seem counterintuitive at first. + */ + ASSERT_ERR(err, "bpf_map_lookup_elem"); + ASSERT_EQ(errno, ENOENT, "bpf_map_lookup_elem"); close_iter: close(iter_fd); @@ -1203,17 +1196,15 @@ static void test_bpf_sk_storage_get(void) do_dummy_read(skel->progs.fill_socket_owner); err = bpf_map_lookup_elem(map_fd, &sock_fd, &val); - if (CHECK(err || val != getpid(), "bpf_map_lookup_elem", - "map value wasn't set correctly (expected %d, got %d, err=%d)\n", - getpid(), val, err)) + if (!ASSERT_OK(err, "bpf_map_lookup_elem") || + !ASSERT_EQ(val, getpid(), "bpf_map_lookup_elem")) goto close_socket; do_dummy_read(skel->progs.negate_socket_local_storage); err = bpf_map_lookup_elem(map_fd, &sock_fd, &val); - CHECK(err || val != -getpid(), "bpf_map_lookup_elem", - "map value wasn't set correctly (expected %d, got %d, err=%d)\n", - -getpid(), val, err); + ASSERT_OK(err, "bpf_map_lookup_elem"); + ASSERT_EQ(val, -getpid(), "bpf_map_lookup_elem"); close_socket: close(sock_fd); @@ -1290,7 +1281,7 @@ static void test_bpf_sk_storage_map(void) /* do some tests */ while ((len = read(iter_fd, buf, sizeof(buf))) > 0) ; - if (CHECK(len < 0, "read", "read failed: %s\n", strerror(errno))) + if (!ASSERT_GE(len, 0, "read")) goto close_iter; /* test results */ -- 2.25.1

6 months, 2 weeks

4
3
0 0

[PATCH v2] selftests/net: synchronize udpgso_bench rx and tx

by Lucas Karpinski

The sockets used by udpgso_bench_tx aren't always ready when udpgso_bench_tx transmits packets. This issue is more prevalent in -rt kernels, but can occur in both. Replace the hacky sleep calls with a function that checks whether the ports in the namespace are ready for use. Suggested-by: Paolo Abeni <pabeni(a)redhat.com> Signed-off-by: Lucas Karpinski <lkarpins(a)redhat.com> --- https://lore.kernel.org/all/t7v6mmuobrbucyfpwqbcujtvpa3wxnsrc36cz5rr6kzzrzk… Changelog v2: - applied synchronization method suggested by Pablo - changed commit message to code tools/testing/selftests/net/udpgro.sh | 27 ++++++++++++++----- tools/testing/selftests/net/udpgro_bench.sh | 19 +++++++++++-- tools/testing/selftests/net/udpgro_frglist.sh | 19 +++++++++++-- 3 files changed, 54 insertions(+), 11 deletions(-) diff --git a/tools/testing/selftests/net/udpgro.sh b/tools/testing/selftests/net/udpgro.sh index 0c743752669a..04792a315729 100755 --- a/tools/testing/selftests/net/udpgro.sh +++ b/tools/testing/selftests/net/udpgro.sh @@ -24,6 +24,22 @@ cleanup() { } trap cleanup EXIT +wait_local_port_listen() +{ + local port="${1}" + + local port_hex + port_hex="$(printf "%04X" "${port}")" + + local i + for i in $(seq 10); do + ip netns exec "${PEER_NS}" cat /proc/net/udp* | \ + awk "BEGIN {rc=1} {if (\$2 ~ /:${port_hex}\$/) {rc=0; exit}} END {exit rc}" && + break + sleep 0.1 + done +} + cfg_veth() { ip netns add "${PEER_NS}" ip -netns "${PEER_NS}" link set lo up @@ -51,8 +67,7 @@ run_one() { echo "ok" || \ echo "failed" & - # Hack: let bg programs complete the startup - sleep 0.2 + wait_local_port_listen 8000 ./udpgso_bench_tx ${tx_args} ret=$? wait $(jobs -p) @@ -97,7 +112,7 @@ run_one_nat() { echo "ok" || \ echo "failed"& - sleep 0.1 + wait_local_port_listen 8000 ./udpgso_bench_tx ${tx_args} ret=$? kill -INT $pid @@ -118,11 +133,9 @@ run_one_2sock() { echo "ok" || \ echo "failed" & - # Hack: let bg programs complete the startup - sleep 0.2 + wait_local_port_listen 12345 ./udpgso_bench_tx ${tx_args} -p 12345 - sleep 0.1 - # first UDP GSO socket should be closed at this point + wait_local_port_listen 8000 ./udpgso_bench_tx ${tx_args} ret=$? wait $(jobs -p) diff --git a/tools/testing/selftests/net/udpgro_bench.sh b/tools/testing/selftests/net/udpgro_bench.sh index 894972877e8b..91833518e80b 100755 --- a/tools/testing/selftests/net/udpgro_bench.sh +++ b/tools/testing/selftests/net/udpgro_bench.sh @@ -16,6 +16,22 @@ cleanup() { } trap cleanup EXIT +wait_local_port_listen() +{ + local port="${1}" + + local port_hex + port_hex="$(printf "%04X" "${port}")" + + local i + for i in $(seq 10); do + ip netns exec "${PEER_NS}" cat /proc/net/udp* | \ + awk "BEGIN {rc=1} {if (\$2 ~ /:${port_hex}\$/) {rc=0; exit}} END {exit rc}" && + break + sleep 0.1 + done +} + run_one() { # use 'rx' as separator between sender args and receiver args local -r all="$@" @@ -40,8 +56,7 @@ run_one() { ip netns exec "${PEER_NS}" ./udpgso_bench_rx ${rx_args} -r & ip netns exec "${PEER_NS}" ./udpgso_bench_rx -t ${rx_args} -r & - # Hack: let bg programs complete the startup - sleep 0.2 + wait_local_port_listen 8000 ./udpgso_bench_tx ${tx_args} } diff --git a/tools/testing/selftests/net/udpgro_frglist.sh b/tools/testing/selftests/net/udpgro_frglist.sh index 0a6359bed0b9..0aa2068f122c 100755 --- a/tools/testing/selftests/net/udpgro_frglist.sh +++ b/tools/testing/selftests/net/udpgro_frglist.sh @@ -16,6 +16,22 @@ cleanup() { } trap cleanup EXIT +wait_local_port_listen() +{ + local port="${1}" + + local port_hex + port_hex="$(printf "%04X" "${port}")" + + local i + for i in $(seq 10); do + ip netns exec "${PEER_NS}" cat /proc/net/udp* | \ + awk "BEGIN {rc=1} {if (\$2 ~ /:${port_hex}\$/) {rc=0; exit}} END {exit rc}" && + break + sleep 0.1 + done +} + run_one() { # use 'rx' as separator between sender args and receiver args local -r all="$@" @@ -45,8 +61,7 @@ run_one() { echo ${rx_args} ip netns exec "${PEER_NS}" ./udpgso_bench_rx ${rx_args} -r & - # Hack: let bg programs complete the startup - sleep 0.2 + wait_local_port_listen 8000 ./udpgso_bench_tx ${tx_args} } -- 2.41.0

6 months, 2 weeks

3
6
0 0

selftests: user_events: ftrace_test - RIP: 0010:tracing_update_buffers (kernel/trace/trace.c:6470)

by Naresh Kamboju

Following kernel crash noticed on x86_64 while running selftests: user_events: ftrace_test running 6.6.0-rc7-next-20231026. Reported-by: Linux Kernel Functional Testing <lkft(a)linaro.org> kselftest: Running tests in user_events TAP version 13 1..4 # timeout set to 90 # selftests: user_events: ftrace_test [ 2391.606817] general protection fault, probably for non-canonical address 0x6b6b6b6b6b6b8a83: 0000 [#1] PREEMPT SMP PTI [ 2391.617519] CPU: 1 PID: 34662 Comm: ftrace_test Not tainted 6.6.0-rc7-next-20231026 #1 [ 2391.625428] Hardware name: Supermicro SYS-5019S-ML/X11SSH-F, BIOS 2.7 12/07/2021 [ 2391.632811] RIP: 0010:tracing_update_buffers (kernel/trace/trace.c:6470) [ 2391.637952] Code: 90 90 90 90 90 90 90 90 90 90 90 90 66 0f 1f 00 55 31 f6 48 89 e5 41 55 41 54 53 48 89 fb 48 c7 c7 40 8c 61 94 e8 92 d3 5a 01 <44> 0f b6 a3 18 1f 00 00 41 80 fc 01 0f 87 c8 dc 4e 01 45 31 ed 41 All code ======== 0: 90 nop 1: 90 nop 2: 90 nop 3: 90 nop 4: 90 nop 5: 90 nop 6: 90 nop 7: 90 nop 8: 90 nop 9: 90 nop a: 90 nop b: 90 nop c: 66 0f 1f 00 nopw (%rax) 10: 55 push %rbp 11: 31 f6 xor %esi,%esi 13: 48 89 e5 mov %rsp,%rbp 16: 41 55 push %r13 18: 41 54 push %r12 1a: 53 push %rbx 1b: 48 89 fb mov %rdi,%rbx 1e: 48 c7 c7 40 8c 61 94 mov $0xffffffff94618c40,%rdi 25: e8 92 d3 5a 01 callq 0x15ad3bc 2a:* 44 0f b6 a3 18 1f 00 movzbl 0x1f18(%rbx),%r12d <-- trapping instruction 31: 00 32: 41 80 fc 01 cmp $0x1,%r12b 36: 0f 87 c8 dc 4e 01 ja 0x14edd04 3c: 45 31 ed xor %r13d,%r13d 3f: 41 rex.B Code starting with the faulting instruction =========================================== 0: 44 0f b6 a3 18 1f 00 movzbl 0x1f18(%rbx),%r12d 7: 00 8: 41 80 fc 01 cmp $0x1,%r12b c: 0f 87 c8 dc 4e 01 ja 0x14edcda 12: 45 31 ed xor %r13d,%r13d 15: 41 rex.B [ 2391.656696] RSP: 0018:ffffb36e0a477d80 EFLAGS: 00010246 [ 2391.661937] RAX: 0000000000000000 RBX: 6b6b6b6b6b6b6b6b RCX: 0000000080000000 [ 2391.669064] RDX: 0000000000000000 RSI: ffffffff9299b722 RDI: ffffffff9299b722 [ 2391.676195] RBP: ffffb36e0a477d98 R08: 000000000000002f R09: 0000000000000002 [ 2391.683321] R10: ffffb36e0a477d70 R11: 0000000000000000 R12: 0000000000000002 [ 2391.690453] R13: ffffb36e0a477e88 R14: ffff99c5803a2230 R15: ffff99c581c39000 [ 2391.697586] FS: 00007fb4b9681740(0000) GS:ffff99c6efa80000(0000) knlGS:0000000000000000 [ 2391.705670] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 2391.711410] CR2: 00007fb4b96ab5e0 CR3: 000000010635c002 CR4: 00000000003706f0 [ 2391.718540] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 2391.725665] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 2391.732797] Call Trace: [ 2391.735240] <TASK> [ 2391.737339] ? show_regs (arch/x86/kernel/dumpstack.c:479) [ 2391.740744] ? die_addr (arch/x86/kernel/dumpstack.c:421 arch/x86/kernel/dumpstack.c:460) [ 2391.744056] ? exc_general_protection (arch/x86/kernel/traps.c:697 arch/x86/kernel/traps.c:642) [ 2391.748766] ? asm_exc_general_protection (arch/x86/include/asm/idtentry.h:564) [ 2391.753652] ? __mutex_lock (kernel/locking/mutex.c:613 (discriminator 3) kernel/locking/mutex.c:747 (discriminator 3)) [ 2391.757487] ? __mutex_lock (kernel/locking/mutex.c:613 (discriminator 3) kernel/locking/mutex.c:747 (discriminator 3)) [ 2391.761318] ? tracing_update_buffers (kernel/trace/trace.c:6470) [ 2391.765851] event_enable_write (kernel/trace/trace_events.c:1408) [ 2391.769976] vfs_write (fs/read_write.c:582) [ 2391.773296] ? close_fd_get_file (fs/file.c:821) [ 2391.777396] ? preempt_count_sub (kernel/sched/core.c:5857 kernel/sched/core.c:5853 kernel/sched/core.c:5875) [ 2391.781496] ksys_write (fs/read_write.c:638) [ 2391.784918] __x64_sys_write (fs/read_write.c:646) [ 2391.788671] do_syscall_64 (arch/x86/entry/common.c:51 arch/x86/entry/common.c:82) [ 2391.792248] ? do_syscall_64 (arch/x86/entry/common.c:101) [ 2391.795995] ? syscall_exit_to_user_mode (kernel/entry/common.c:299) [ 2391.800785] ? do_syscall_64 (arch/x86/entry/common.c:101) [ 2391.804529] ? do_syscall_64 (arch/x86/entry/common.c:101) [ 2391.808275] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:129) [ 2391.813327] RIP: 0033:0x7fb4b977c140 [ 2391.816920] Code: 40 00 48 8b 15 c1 9c 0d 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b7 0f 1f 00 80 3d a1 24 0e 00 00 74 17 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 58 c3 0f 1f 80 00 00 00 00 48 83 ec 28 48 89 All code ======== 0: 40 00 48 8b add %cl,-0x75(%rax) 4: 15 c1 9c 0d 00 adc $0xd9cc1,%eax 9: f7 d8 neg %eax b: 64 89 02 mov %eax,%fs:(%rdx) e: 48 c7 c0 ff ff ff ff mov $0xffffffffffffffff,%rax 15: eb b7 jmp 0xffffffffffffffce 17: 0f 1f 00 nopl (%rax) 1a: 80 3d a1 24 0e 00 00 cmpb $0x0,0xe24a1(%rip) # 0xe24c2 21: 74 17 je 0x3a 23: b8 01 00 00 00 mov $0x1,%eax 28: 0f 05 syscall 2a:* 48 3d 00 f0 ff ff cmp $0xfffffffffffff000,%rax <-- trapping instruction 30: 77 58 ja 0x8a 32: c3 retq 33: 0f 1f 80 00 00 00 00 nopl 0x0(%rax) 3a: 48 83 ec 28 sub $0x28,%rsp 3e: 48 rex.W 3f: 89 .byte 0x89 Code starting with the faulting instruction =========================================== 0: 48 3d 00 f0 ff ff cmp $0xfffffffffffff000,%rax 6: 77 58 ja 0x60 8: c3 retq 9: 0f 1f 80 00 00 00 00 nopl 0x0(%rax) 10: 48 83 ec 28 sub $0x28,%rsp 14: 48 rex.W 15: 89 .byte 0x89 [ 2391.835660] RSP: 002b:00007ffc43b05b38 EFLAGS: 00000202 ORIG_RAX: 0000000000000001 [ 2391.843225] RAX: ffffffffffffffda RBX: 00007ffc43b05d88 RCX: 00007fb4b977c140 [ 2391.850350] RDX: 0000000000000002 RSI: 000056376b59b7d4 RDI: 0000000000000007 [ 2391.857482] RBP: 00007ffc43b05b60 R08: 0000000000000000 R09: 00007fb4b9681740 [ 2391.864615] R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000 [ 2391.871747] R13: 00007ffc43b05d98 R14: 000056376b59ddc8 R15: 00007fb4b9981020 [ 2391.878907] </TASK> [ 2391.881106] Modules linked in: x86_pkg_temp_thermal fuse configfs [ 2391.887288] ---[ end trace 0000000000000000 ]--- [ 2391.891915] RIP: 0010:tracing_update_buffers (kernel/trace/trace.c:6470) [ 2391.897231] Code: 90 90 90 90 90 90 90 90 90 90 90 90 66 0f 1f 00 55 31 f6 48 89 e5 41 55 41 54 53 48 89 fb 48 c7 c7 40 8c 61 94 e8 92 d3 5a 01 <44> 0f b6 a3 18 1f 00 00 41 80 fc 01 0f 87 c8 dc 4e 01 45 31 ed 41 All code ======== 0: 90 nop 1: 90 nop 2: 90 nop 3: 90 nop 4: 90 nop 5: 90 nop 6: 90 nop 7: 90 nop 8: 90 nop 9: 90 nop a: 90 nop b: 90 nop c: 66 0f 1f 00 nopw (%rax) 10: 55 push %rbp 11: 31 f6 xor %esi,%esi 13: 48 89 e5 mov %rsp,%rbp 16: 41 55 push %r13 18: 41 54 push %r12 1a: 53 push %rbx 1b: 48 89 fb mov %rdi,%rbx 1e: 48 c7 c7 40 8c 61 94 mov $0xffffffff94618c40,%rdi 25: e8 92 d3 5a 01 callq 0x15ad3bc 2a:* 44 0f b6 a3 18 1f 00 movzbl 0x1f18(%rbx),%r12d <-- trapping instruction 31: 00 32: 41 80 fc 01 cmp $0x1,%r12b 36: 0f 87 c8 dc 4e 01 ja 0x14edd04 3c: 45 31 ed xor %r13d,%r13d 3f: 41 rex.B Code starting with the faulting instruction =========================================== 0: 44 0f b6 a3 18 1f 00 movzbl 0x1f18(%rbx),%r12d 7: 00 8: 41 80 fc 01 cmp $0x1,%r12b c: 0f 87 c8 dc 4e 01 ja 0x14edcda 12: 45 31 ed xor %r13d,%r13d 15: 41 rex.B [ 2391.916120] RSP: 0018:ffffb36e0a477d80 EFLAGS: 00010246 [ 2391.921569] RAX: 0000000000000000 RBX: 6b6b6b6b6b6b6b6b RCX: 0000000080000000 [ 2391.928872] RDX: 0000000000000000 RSI: ffffffff9299b722 RDI: ffffffff9299b722 [ 2391.936237] RBP: ffffb36e0a477d98 R08: 000000000000002f R09: 0000000000000002 [ 2391.943388] R10: ffffb36e0a477d70 R11: 0000000000000000 R12: 0000000000000002 [ 2391.950527] R13: ffffb36e0a477e88 R14: ffff99c5803a2230 R15: ffff99c581c39000 [ 2391.957670] FS: 00007fb4b9681740(0000) GS:ffff99c6efa80000(0000) knlGS:0000000000000000 [ 2391.965822] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 2391.971579] CR2: 00007fb4b96ab5e0 CR3: 000000010635c002 CR4: 00000000003706f0 [ 2391.978721] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 2391.985879] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 2391.993028] Kernel panic - not syncing: Fatal exception [ 2391.998287] Kernel Offset: 0x10000000 from 0xffffffff81000000 (relocation range: 0xffffffff80000000-0xffffffffbfffffff) [ 2392.009066] ---[ end Kernel panic - not syncing: Fatal exception ]--- Links: - https://qa-reports.linaro.org/lkft/linux-next-master/build/next-20231026/te… - https://lkft.validation.linaro.org/scheduler/job/6974179#L5053 metadata: git_ref: master git_repo: https://gitlab.com/Linaro/lkft/mirrors/next/linux-next git_sha: 2ef7141596eed0b4b45ef18b3626f428a6b0a822 git_describe: next-20231026 kernel_version: 6.6.0-rc7 kernel-config: https://storage.tuxsuite.com/public/linaro/lkft/builds/2XHt24sNSdog7DYY3FLK… artifact-location: https://storage.tuxsuite.com/public/linaro/lkft/builds/2XHt24sNSdog7DYY3FLK… toolchain: gcc-13 -- Linaro LKFT https://lkft.linaro.org

6 months, 2 weeks

3
12
0 0

[RFC bpf-next 0/6] Add bpf_xdp_get_xfrm_state() kfunc

by Daniel Xu

This patchset adds a kfunc helper, bpf_xdp_get_xfrm_state(), that wraps xfrm_state_lookup(). The intent is to support software RSS (via XDP) for the ongoing/upcoming ipsec pcpu work [0]. Recent experiments performed on (hopefully) reproducible AWS testbeds indicate that single tunnel pcpu ipsec can reach line rate on 100G ENA nics. More details about that will be presented at netdev next week [1]. Antony did the initial stable bpf helper - I later ported it to unstable kfuncs. So for the series, please apply a Co-developed-by for Antony, provided he acks and signs off on this. [0]: https://datatracker.ietf.org/doc/html/draft-ietf-ipsecme-multi-sa-performan… [1]: https://netdevconf.info/0x17/sessions/workshop/security-workshop.html Daniel Xu (6): bpf: xfrm: Add bpf_xdp_get_xfrm_state() kfunc bpf: selftests: test_tunnel: Use ping -6 over ping6 bpf: selftests: test_tunnel: Mount bpffs if necessary bpf: selftests: test_tunnel: Use vmlinux.h declarations bpf: selftests: test_tunnel: Disable CO-RE relocations bpf: xfrm: Add selftest for bpf_xdp_get_xfrm_state() include/net/xfrm.h | 9 ++ net/xfrm/Makefile | 1 + net/xfrm/xfrm_policy.c | 2 + net/xfrm/xfrm_state_bpf.c | 105 ++++++++++++++++++ .../selftests/bpf/progs/bpf_tracing_net.h | 1 + .../selftests/bpf/progs/test_tunnel_kern.c | 95 +++++++++------- tools/testing/selftests/bpf/test_tunnel.sh | 43 ++++--- 7 files changed, 202 insertions(+), 54 deletions(-) create mode 100644 net/xfrm/xfrm_state_bpf.c -- 2.42.0

6 months, 3 weeks

3
9
0 0

[PATCH bpf-next v3 2/2] selftests/bpf: Add malloc failure checks in bpf_iter

by Yuran Pereira

Since some malloc calls in bpf_iter may at times fail, this patch adds the appropriate fail checks, and ensures that any previously allocated resource is appropriately destroyed before returning the function. Signed-off-by: Yuran Pereira <yuran.pereira(a)hotmail.com> --- tools/testing/selftests/bpf/prog_tests/bpf_iter.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/tools/testing/selftests/bpf/prog_tests/bpf_iter.c b/tools/testing/selftests/bpf/prog_tests/bpf_iter.c index 123a3502b8f0..1e02d1ba1c18 100644 --- a/tools/testing/selftests/bpf/prog_tests/bpf_iter.c +++ b/tools/testing/selftests/bpf/prog_tests/bpf_iter.c @@ -698,7 +698,7 @@ static void test_overflow(bool test_e2big_overflow, bool ret1) goto free_link; buf = malloc(expected_read_len); - if (!buf) + if (!ASSERT_OK_PTR(buf, "malloc")) goto close_iter; /* do read */ @@ -868,6 +868,8 @@ static void test_bpf_percpu_hash_map(void) skel->rodata->num_cpus = bpf_num_possible_cpus(); val = malloc(8 * bpf_num_possible_cpus()); + if (!ASSERT_OK_PTR(val, "malloc")) + goto out; err = bpf_iter_bpf_percpu_hash_map__load(skel); if (!ASSERT_OK_PTR(skel, "bpf_iter_bpf_percpu_hash_map__load")) @@ -1044,6 +1046,8 @@ static void test_bpf_percpu_array_map(void) skel->rodata->num_cpus = bpf_num_possible_cpus(); val = malloc(8 * bpf_num_possible_cpus()); + if (!ASSERT_OK_PTR(val, "malloc")) + goto out; err = bpf_iter_bpf_percpu_array_map__load(skel); if (!ASSERT_OK_PTR(skel, "bpf_iter_bpf_percpu_array_map__load")) -- 2.25.1

6 months, 3 weeks

3
2
0 0

[PATCH v2 00/20] Permission Overlay Extension

by Joey Gouly

Hello everyone, This series implements the Permission Overlay Extension introduced in 2022 VMSA enhancements [1]. It is based on v6.6-rc3. Changes since v1[2]: # Added Kconfig option # Added KVM support # Move VM_PKEY* defines into arch/ # Add isb() for POR_EL0 context switch # Added hwcap test, get-reg-list-test, signal frame handling test ptrace support is missing, I will add that for v3. The Permission Overlay Extension allows to constrain permissions on memory regions. This can be used from userspace (EL0) without a system call or TLB invalidation. POE is used to implement the Memory Protection Keys [3] Linux syscall. The first few patches add the basic framework, then the PKEYS interface is implemented, and then the selftests are made to work on arm64. There was discussion about what the 'default' protection key value should be, I used disallow-all (apart from pkey 0), which matches what x86 does. I have tested the modified protection_keys test on x86_64 [5], but not PPC. I haven't build tested the x86/ppc changes, will work on getting at least an x86 build environment working. Thanks, Joey [1] https://community.arm.com/arm-community-blogs/b/architectures-and-processor… [2] https://lore.kernel.org/linux-arm-kernel/20230927140123.5283-1-joey.gouly@a… [3] Documentation/core-api/protection-keys.rst [4] https://lore.kernel.org/linux-arm-kernel/20230919092850.1940729-7-mark.rutl… [5] test_ptrace_modifies_pkru asserts for me on a Ubuntu 5.4 kernel, but does so before my changes as well Joey Gouly (24): arm64/sysreg: add system register POR_EL{0,1} arm64/sysreg: update CPACR_EL1 register arm64: cpufeature: add Permission Overlay Extension cpucap arm64: disable trapping of POR_EL0 to EL2 arm64: context switch POR_EL0 register KVM: arm64: Save/restore POE registers arm64: enable the Permission Overlay Extension for EL0 arm64: add POIndex defines arm64: define VM_PKEY_BIT* for arm64 arm64: mask out POIndex when modifying a PTE arm64: enable ARCH_HAS_PKEYS on arm64 arm64: handle PKEY/POE faults arm64: stop using generic mm_hooks.h arm64: implement PKEYS support arm64: add POE signal support arm64: enable PKEY support for CPUs with S1POE arm64: enable POE and PIE to coexist kselftest/arm64: move get_header() selftests: mm: move fpregs printing selftests: mm: make protection_keys test work on arm64 kselftest/arm64: add HWCAP test for FEAT_S1POE kselftest/arm64: parse POE_MAGIC in a signal frame kselftest/arm64: Add test case for POR_EL0 signal frame records KVM: selftests: get-reg-list: add Permission Overlay registers Documentation/arch/arm64/elf_hwcaps.rst | 3 + arch/arm64/Kconfig | 18 +++ arch/arm64/include/asm/cpufeature.h | 6 + arch/arm64/include/asm/el2_setup.h | 10 +- arch/arm64/include/asm/hwcap.h | 1 + arch/arm64/include/asm/kvm_arm.h | 4 +- arch/arm64/include/asm/kvm_host.h | 4 + arch/arm64/include/asm/mman.h | 8 +- arch/arm64/include/asm/mmu.h | 2 + arch/arm64/include/asm/mmu_context.h | 51 ++++++- arch/arm64/include/asm/page.h | 10 ++ arch/arm64/include/asm/pgtable-hwdef.h | 10 ++ arch/arm64/include/asm/pgtable-prot.h | 8 +- arch/arm64/include/asm/pgtable.h | 26 +++- arch/arm64/include/asm/pkeys.h | 110 ++++++++++++++ arch/arm64/include/asm/por.h | 33 +++++ arch/arm64/include/asm/processor.h | 1 + arch/arm64/include/asm/sysreg.h | 16 ++ arch/arm64/include/asm/traps.h | 1 + arch/arm64/include/uapi/asm/hwcap.h | 1 + arch/arm64/include/uapi/asm/sigcontext.h | 7 + arch/arm64/kernel/cpufeature.c | 23 +++ arch/arm64/kernel/cpuinfo.c | 1 + arch/arm64/kernel/process.c | 19 +++ arch/arm64/kernel/signal.c | 51 +++++++ arch/arm64/kernel/traps.c | 12 +- arch/arm64/kvm/hyp/include/hyp/sysreg-sr.h | 10 ++ arch/arm64/kvm/sys_regs.c | 2 + arch/arm64/mm/fault.c | 44 +++++- arch/arm64/mm/mmap.c | 9 ++ arch/arm64/mm/mmu.c | 40 +++++ arch/arm64/tools/cpucaps | 1 + arch/arm64/tools/sysreg | 15 +- arch/powerpc/include/asm/page.h | 11 ++ arch/x86/include/asm/page.h | 10 ++ fs/proc/task_mmu.c | 2 + include/linux/mm.h | 13 -- tools/testing/selftests/arm64/abi/hwcap.c | 13 ++ .../testing/selftests/arm64/signal/.gitignore | 1 + .../arm64/signal/testcases/poe_siginfo.c | 86 +++++++++++ .../arm64/signal/testcases/testcases.c | 27 +--- .../arm64/signal/testcases/testcases.h | 28 +++- .../selftests/kvm/aarch64/get-reg-list.c | 14 ++ tools/testing/selftests/mm/Makefile | 2 +- tools/testing/selftests/mm/pkey-arm64.h | 138 ++++++++++++++++++ tools/testing/selftests/mm/pkey-helpers.h | 8 + tools/testing/selftests/mm/pkey-powerpc.h | 3 + tools/testing/selftests/mm/pkey-x86.h | 4 + tools/testing/selftests/mm/protection_keys.c | 29 ++-- 49 files changed, 880 insertions(+), 66 deletions(-) create mode 100644 arch/arm64/include/asm/pkeys.h create mode 100644 arch/arm64/include/asm/por.h create mode 100644 tools/testing/selftests/arm64/signal/testcases/poe_siginfo.c create mode 100644 tools/testing/selftests/mm/pkey-arm64.h -- 2.25.1

6 months, 3 weeks

2
27
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[PATCH RFC RFT 0/5] fork: Support shadow stacks in clone3()

by Mark Brown

The kernel has recently added support for shadow stacks, currently x86 only using their CET feature but both arm64 and RISC-V have equivalent features (GCS and Zisslpcfi respectively), I am actively working on GCS[1]. With shadow stacks the hardware maintains an additional stack containing only the return addresses for branch instructions which is not generally writeable by userspace and ensures that any returns are to the recorded addresses. This provides some protection against ROP attacks and making it easier to collect call stacks. These shadow stacks are allocated in the address space of the userspace process. Our API for shadow stacks does not currently offer userspace any flexiblity for managing the allocation of shadow stacks for newly created threads, instead the kernel allocates a new shadow stack with the same size as the normal stack whenever a thread is created with the feature enabled. The stacks allocated in this way are freed by the kernel when the thread exits or shadow stacks are disabled for the thread. This lack of flexibility and control isn't ideal, in the vast majority of cases the shadow stack will be over allocated and the implicit allocation and deallocation is not consistent with other interfaces. As far as I can tell the interface is done in this manner mainly because the shadow stack patches were in development since before clone3() was implemented. Since clone3() is readily extensible let's add support for specifying a shadow stack when creating a new thread or process in a similar manner to how the normal stack is specified, keeping the current implicit allocation behaviour if one is not specified either with clone3() or through the use of clone(). When the shadow stack is specified explicitly the kernel will not free it, the inconsistency with implicitly allocated shadow stacks is a bit awkward but that's existing ABI so we can't change it. The memory provided must have been allocated for use as a shadow stack, the expectation is that this will be done using the map_shadow_stack() syscall. I opted not to add validation for this in clone3() since it will be enforced by hardware anyway. Please note that the x86 portions of this code are build tested only, I don't appear to have a system that can run CET avaible to me, I have done testing with an integration into my pending work for GCS. There is some possibility that the arm64 implementation may require the use of clone3() and explicit userspace allocation of shadow stacks, this is still under discussion. A new architecture feature Kconfig option for shadow stacks is added as here, this was suggested as part of the review comments for the arm64 GCS series and since we need to detect if shadow stacks are supported it seemed sensible to roll it in here. The selftest portions of this depend on 34dce23f7e40 ("selftests/clone3: Report descriptive test names") in -next[2]. [1] https://lore.kernel.org/r/20231009-arm64-gcs-v6-0-78e55deaa4dd@kernel.org/ [2] https://lore.kernel.org/r/20231018-kselftest-clone3-output-v1-1-12b7c50ea2c… Signed-off-by: Mark Brown <broonie(a)kernel.org> --- Mark Brown (5): mm: Introduce ARCH_HAS_USER_SHADOW_STACK fork: Add shadow stack support to clone3() selftests/clone3: Factor more of main loop into test_clone3() selftests/clone3: Allow tests to flag if -E2BIG is a valid error code kselftest/clone3: Test shadow stack support arch/x86/Kconfig | 1 + arch/x86/include/asm/shstk.h | 11 +- arch/x86/kernel/process.c | 2 +- arch/x86/kernel/shstk.c | 36 ++++- fs/proc/task_mmu.c | 2 +- include/linux/mm.h | 2 +- include/linux/sched/task.h | 2 + include/uapi/linux/sched.h | 17 +- kernel/fork.c | 40 ++++- mm/Kconfig | 6 + tools/testing/selftests/clone3/clone3.c | 180 +++++++++++++++++----- tools/testing/selftests/clone3/clone3_selftests.h | 5 + 12 files changed, 247 insertions(+), 57 deletions(-) --- base-commit: 80ab9b52e8d4add7735abdfb935877354b69edb6 change-id: 20231019-clone3-shadow-stack-15d40d2bf536 Best regards, -- Mark Brown <broonie(a)kernel.org>

6 months, 3 weeks

4
19
0 0

[PATCH v4 0/5] workload-specific and memory pressure-driven zswap writeback

by Nhat Pham

Changelog: v4: * Rename list_lru_add to list_lru_add_obj and __list_lru_add to list_lru_add (patch 1) (suggested by Johannes Weiner and Yosry Ahmed) * Some cleanups on the memcg aware LRU patch (patch 2) (suggested by Yosry Ahmed) * Use event interface for the new per-cgroup writeback counters. (patch 3) (suggested by Yosry Ahmed) * Abstract zswap's lruvec states and handling into zswap_lruvec_state (patch 5) (suggested by Yosry Ahmed) v3: * Add a patch to export per-cgroup zswap writeback counters * Add a patch to update zswap's kselftest * Separate the new list_lru functions into its own prep patch * Do not start from the top of the hierarchy when encounter a memcg that is not online for the global limit zswap writeback (patch 2) (suggested by Yosry Ahmed) * Do not remove the swap entry from list_lru in __read_swapcache_async() (patch 2) (suggested by Yosry Ahmed) * Removed a redundant zswap pool getting (patch 2) (reported by Ryan Roberts) * Use atomic for the nr_zswap_protected (instead of lruvec's lock) (patch 5) (suggested by Yosry Ahmed) * Remove the per-cgroup zswap shrinker knob (patch 5) (suggested by Yosry Ahmed) v2: * Fix loongarch compiler errors * Use pool stats instead of memcg stats when !CONFIG_MEMCG_KEM There are currently several issues with zswap writeback: 1. There is only a single global LRU for zswap, making it impossible to perform worload-specific shrinking - an memcg under memory pressure cannot determine which pages in the pool it owns, and often ends up writing pages from other memcgs. This issue has been previously observed in practice and mitigated by simply disabling memcg-initiated shrinking: https://lore.kernel.org/all/20230530232435.3097106-1-nphamcs@gmail.com/T/#u But this solution leaves a lot to be desired, as we still do not have an avenue for an memcg to free up its own memory locked up in the zswap pool. 2. We only shrink the zswap pool when the user-defined limit is hit. This means that if we set the limit too high, cold data that are unlikely to be used again will reside in the pool, wasting precious memory. It is hard to predict how much zswap space will be needed ahead of time, as this depends on the workload (specifically, on factors such as memory access patterns and compressibility of the memory pages). This patch series solves these issues by separating the global zswap LRU into per-memcg and per-NUMA LRUs, and performs workload-specific (i.e memcg- and NUMA-aware) zswap writeback under memory pressure. The new shrinker does not have any parameter that must be tuned by the user, and can be opted in or out on a per-memcg basis. As a proof of concept, we ran the following synthetic benchmark: build the linux kernel in a memory-limited cgroup, and allocate some cold data in tmpfs to see if the shrinker could write them out and improved the overall performance. Depending on the amount of cold data generated, we observe from 14% to 35% reduction in kernel CPU time used in the kernel builds. Domenico Cerasuolo (3): zswap: make shrinking memcg-aware mm: memcg: add per-memcg zswap writeback stat selftests: cgroup: update per-memcg zswap writeback selftest Nhat Pham (2): list_lru: allows explicit memcg and NUMA node selection zswap: shrinks zswap pool based on memory pressure Documentation/admin-guide/mm/zswap.rst | 7 + drivers/android/binder_alloc.c | 5 +- fs/dcache.c | 8 +- fs/gfs2/quota.c | 6 +- fs/inode.c | 4 +- fs/nfs/nfs42xattr.c | 8 +- fs/nfsd/filecache.c | 4 +- fs/xfs/xfs_buf.c | 6 +- fs/xfs/xfs_dquot.c | 2 +- fs/xfs/xfs_qm.c | 2 +- include/linux/list_lru.h | 46 ++- include/linux/memcontrol.h | 5 + include/linux/mmzone.h | 2 + include/linux/vm_event_item.h | 1 + include/linux/zswap.h | 25 +- mm/list_lru.c | 48 ++- mm/memcontrol.c | 1 + mm/mmzone.c | 1 + mm/swap.h | 3 +- mm/swap_state.c | 25 +- mm/vmstat.c | 1 + mm/workingset.c | 4 +- mm/zswap.c | 365 ++++++++++++++++---- tools/testing/selftests/cgroup/test_zswap.c | 74 ++-- 24 files changed, 526 insertions(+), 127 deletions(-) -- 2.34.1

6 months, 3 weeks

2
9
0 0

[PATCH net] selftests: pmtu.sh: fix result checking

by Hangbin Liu

In the PMTU test, when all previous tests are skipped and the new test passes, the exit code is set to 0. However, the current check mistakenly treats this as an assignment, causing the check to pass every time. Consequently, regardless of how many tests have failed, if the latest test passes, the PMTU test will report a pass. Fixes: 2a9d3716b810 ("selftests: pmtu.sh: improve the test result processing") Signed-off-by: Hangbin Liu <liuhangbin(a)gmail.com> --- tools/testing/selftests/net/pmtu.sh | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/tools/testing/selftests/net/pmtu.sh b/tools/testing/selftests/net/pmtu.sh index f838dd370f6a..b9648da4c371 100755 --- a/tools/testing/selftests/net/pmtu.sh +++ b/tools/testing/selftests/net/pmtu.sh @@ -2048,7 +2048,7 @@ run_test() { case $ret in 0) all_skipped=false - [ $exitcode=$ksft_skip ] && exitcode=0 + [ $exitcode = $ksft_skip ] && exitcode=0 ;; $ksft_skip) [ $all_skipped = true ] && exitcode=$ksft_skip -- 2.41.0

6 months, 3 weeks

2
1
0 0

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