- Linux-kselftest-mirror - lists.linaro.org

[PATCH net-next v2 0/4] nexthop: Refactor and fix nexthop selection for multipath routes

by Benjamin Poirier

In order to select a nexthop for multipath routes, fib_select_multipath() is used with legacy nexthops and nexthop_select_path_hthr() is used with nexthop objects. Those two functions perform a validity test on the neighbor related to each nexthop but their logic is structured differently. This causes a divergence in behavior and nexthop_select_path_hthr() may return a nexthop that failed the neighbor validity test even if there was one that passed. Refactor nexthop_select_path_hthr() to make it more similar to fib_select_multipath() and fix the problem mentioned above. v2: Removed unnecessary "first" variable in "nexthop: Do not return invalid nexthop object during multipath selection". v1: https://lore.kernel.org/netdev/20230529201914.69828-1-bpoirier@nvidia.com/ --- Benjamin Poirier (4): nexthop: Factor out hash threshold fdb nexthop selection nexthop: Factor out neighbor validity check nexthop: Do not return invalid nexthop object during multipath selection selftests: net: Add test cases for nexthop groups with invalid neighbors net/ipv4/nexthop.c | 61 +++++++++---- tools/testing/selftests/net/fib_nexthops.sh | 129 ++++++++++++++++++++++++++++ 2 files changed, 171 insertions(+), 19 deletions(-) --- base-commit: 36395b2efe905650cd179d67411ffee3b770268b change-id: 20230719-nh_select-0303d55a1fb0 Best regards, -- Benjamin Poirier <bpoirier(a)nvidia.com>

2 years, 4 months

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Re: Re: fs/proc/task_mmu: Implement IOCTL for efficient page table scanning

by kernel test robot

Hi Michał, kernel test robot noticed the following build errors: [auto build test ERROR on akpm-mm/mm-everything] [also build test ERROR on linus/master v6.5-rc2 next-20230720] [If your patch is applied to the wrong git tree, kindly drop us a note. And when submitting patch, we suggest to use '--base' as documented in https://git-scm.com/docs/git-format-patch#_base_tree_information] url: https://github.com/intel-lab-lkp/linux/commits/Micha-Miros-aw/Re-fs-proc-ta… base: https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git mm-everything patch link: https://lore.kernel.org/r/a0b5c6776b2ed91f78a7575649f8b100e58bd3a9.16898810… patch subject: Re: fs/proc/task_mmu: Implement IOCTL for efficient page table scanning config: arc-randconfig-r035-20230720 (https://download.01.org/0day-ci/archive/20230721/202307211030.2CJH6TkM-lkp@…) compiler: arceb-elf-gcc (GCC) 12.3.0 reproduce: (https://download.01.org/0day-ci/archive/20230721/202307211030.2CJH6TkM-lkp@…) If you fix the issue in a separate patch/commit (i.e. not just a new version of the same patch/commit), kindly add following tags | Reported-by: kernel test robot <lkp(a)intel.com> | Closes: https://lore.kernel.org/oe-kbuild-all/202307211030.2CJH6TkM-lkp@intel.com/ All errors (new ones prefixed by >>): fs/proc/task_mmu.c: In function 'pagemap_scan_test_walk': fs/proc/task_mmu.c:1921:13: error: implicit declaration of function 'userfaultfd_wp_async'; did you mean 'userfaultfd_wp'? [-Werror=implicit-function-declaration] 1921 | if (userfaultfd_wp_async(vma) && userfaultfd_wp_use_markers(vma)) | ^~~~~~~~~~~~~~~~~~~~ | userfaultfd_wp fs/proc/task_mmu.c: In function 'pagemap_scan_pte_hole': >> fs/proc/task_mmu.c:2200:19: error: implicit declaration of function 'uffd_wp_range' [-Werror=implicit-function-declaration] 2200 | int err = uffd_wp_range(vma, addr, end - addr, true); | ^~~~~~~~~~~~~ fs/proc/task_mmu.c: In function 'pagemap_scan_init_bounce_buffer': fs/proc/task_mmu.c:2290:22: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast] 2290 | p->vec_out = (void __user *)p->arg.vec; | ^ fs/proc/task_mmu.c: At top level: fs/proc/task_mmu.c:1967:13: warning: 'pagemap_scan_backout_range' defined but not used [-Wunused-function] 1967 | static void pagemap_scan_backout_range(struct pagemap_scan_private *p, | ^~~~~~~~~~~~~~~~~~~~~~~~~~ cc1: some warnings being treated as errors vim +/uffd_wp_range +2200 fs/proc/task_mmu.c 2182 2183 static int pagemap_scan_pte_hole(unsigned long addr, unsigned long end, 2184 int depth, struct mm_walk *walk) 2185 { 2186 struct pagemap_scan_private *p = walk->private; 2187 struct vm_area_struct *vma = walk->vma; 2188 int ret; 2189 2190 if (!vma || !pagemap_scan_is_interesting_page(p->cur_vma_category, p)) 2191 return 0; 2192 2193 ret = pagemap_scan_output(p->cur_vma_category, p, addr, &end); 2194 if (addr == end) 2195 return ret; 2196 2197 if (~p->arg.flags & PM_SCAN_WP_MATCHING) 2198 return ret; 2199 > 2200 int err = uffd_wp_range(vma, addr, end - addr, true); 2201 if (err < 0) 2202 ret = err; 2203 2204 return ret; 2205 } 2206 -- 0-DAY CI Kernel Test Service https://github.com/intel/lkp-tests/wiki

2 years, 4 months

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Re: Re: fs/proc/task_mmu: Implement IOCTL for efficient page table scanning

by kernel test robot

Hi Michał, kernel test robot noticed the following build warnings: [auto build test WARNING on akpm-mm/mm-everything] [also build test WARNING on linus/master v6.5-rc2 next-20230720] [If your patch is applied to the wrong git tree, kindly drop us a note. And when submitting patch, we suggest to use '--base' as documented in https://git-scm.com/docs/git-format-patch#_base_tree_information] url: https://github.com/intel-lab-lkp/linux/commits/Micha-Miros-aw/Re-fs-proc-ta… base: https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git mm-everything patch link: https://lore.kernel.org/r/a0b5c6776b2ed91f78a7575649f8b100e58bd3a9.16898810… patch subject: Re: fs/proc/task_mmu: Implement IOCTL for efficient page table scanning config: mips-allyesconfig (https://download.01.org/0day-ci/archive/20230721/202307210528.2qgK1vwi-lkp@…) compiler: mips-linux-gcc (GCC) 12.3.0 reproduce: (https://download.01.org/0day-ci/archive/20230721/202307210528.2qgK1vwi-lkp@…) If you fix the issue in a separate patch/commit (i.e. not just a new version of the same patch/commit), kindly add following tags | Reported-by: kernel test robot <lkp(a)intel.com> | Closes: https://lore.kernel.org/oe-kbuild-all/202307210528.2qgK1vwi-lkp@intel.com/ All warnings (new ones prefixed by >>): fs/proc/task_mmu.c: In function 'pagemap_scan_test_walk': fs/proc/task_mmu.c:1921:13: error: implicit declaration of function 'userfaultfd_wp_async'; did you mean 'userfaultfd_wp'? [-Werror=implicit-function-declaration] 1921 | if (userfaultfd_wp_async(vma) && userfaultfd_wp_use_markers(vma)) | ^~~~~~~~~~~~~~~~~~~~ | userfaultfd_wp fs/proc/task_mmu.c: In function 'pagemap_scan_init_bounce_buffer': >> fs/proc/task_mmu.c:2290:22: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast] 2290 | p->vec_out = (void __user *)p->arg.vec; | ^ fs/proc/task_mmu.c: At top level: fs/proc/task_mmu.c:1967:13: warning: 'pagemap_scan_backout_range' defined but not used [-Wunused-function] 1967 | static void pagemap_scan_backout_range(struct pagemap_scan_private *p, | ^~~~~~~~~~~~~~~~~~~~~~~~~~ cc1: some warnings being treated as errors vim +2290 fs/proc/task_mmu.c 2264 2265 static int pagemap_scan_init_bounce_buffer(struct pagemap_scan_private *p) 2266 { 2267 if (!p->arg.vec_len) { 2268 /* 2269 * An arbitrary non-page-aligned sentinel value for 2270 * pagemap_scan_push_range(). 2271 */ 2272 p->cur_buf.start = p->cur_buf.end = ULLONG_MAX; 2273 return 0; 2274 } 2275 2276 /* 2277 * Allocate a smaller buffer to get output from inside the page 2278 * walk functions and walk the range in PAGEMAP_WALK_SIZE chunks. 2279 * The last range is always stored in p.cur_buf to allow coalescing 2280 * consecutive ranges that have the same categories returned across 2281 * walk_page_range() calls. 2282 */ 2283 p->vec_buf_len = min_t(size_t, PAGEMAP_WALK_SIZE >> PAGE_SHIFT, 2284 p->arg.vec_len - 1); 2285 p->vec_buf = kmalloc_array(p->vec_buf_len, sizeof(*p->vec_buf), 2286 GFP_KERNEL); 2287 if (!p->vec_buf) 2288 return -ENOMEM; 2289 > 2290 p->vec_out = (void __user *)p->arg.vec; 2291 2292 return 0; 2293 } 2294 -- 0-DAY CI Kernel Test Service https://github.com/intel/lkp-tests/wiki

2 years, 4 months

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[PATCH bpf-next v5 0/5] Support defragmenting IPv(4|6) packets in BPF

by Daniel Xu

=== Context === In the context of a middlebox, fragmented packets are tricky to handle. The full 5-tuple of a packet is often only available in the first fragment which makes enforcing consistent policy difficult. There are really only two stateless options, neither of which are very nice: 1. Enforce policy on first fragment and accept all subsequent fragments. This works but may let in certain attacks or allow data exfiltration. 2. Enforce policy on first fragment and drop all subsequent fragments. This does not really work b/c some protocols may rely on fragmentation. For example, DNS may rely on oversized UDP packets for large responses. So stateful tracking is the only sane option. RFC 8900 [0] calls this out as well in section 6.3: Middleboxes [...] should process IP fragments in a manner that is consistent with [RFC0791] and [RFC8200]. In many cases, middleboxes must maintain state in order to achieve this goal. === BPF related bits === Policy has traditionally been enforced from XDP/TC hooks. Both hooks run before kernel reassembly facilities. However, with the new BPF_PROG_TYPE_NETFILTER, we can rather easily hook into existing netfilter reassembly infra. The basic idea is we bump a refcnt on the netfilter defrag module and then run the bpf prog after the defrag module runs. This allows bpf progs to transparently see full, reassembled packets. The nice thing about this is that progs don't have to carry around logic to detect fragments. === Changelog === Changes from v4: * Refactor module handling code to not sleep in rcu_read_lock() * Also unify the v4 and v6 hook structs so they can share codepaths * Fixed some checkpatch.pl formatting warnings Changes from v3: * Correctly initialize `addrlen` stack var for recvmsg() Changes from v2: * module_put() if ->enable() fails * Fix CI build errors Changes from v1: * Drop bpf_program__attach_netfilter() patches * static -> static const where appropriate * Fix callback assignment order during registration * Only request_module() if callbacks are missing * Fix retval when modprobe fails in userspace * Fix v6 defrag module name (nf_defrag_ipv6_hooks -> nf_defrag_ipv6) * Simplify priority checking code * Add warning if module doesn't assign callbacks in the future * Take refcnt on module while defrag link is active [0]: https://datatracker.ietf.org/doc/html/rfc8900 Daniel Xu (5): netfilter: defrag: Add glue hooks for enabling/disabling defrag netfilter: bpf: Support BPF_F_NETFILTER_IP_DEFRAG in netfilter link bpf: selftests: Support not connecting client socket bpf: selftests: Support custom type and proto for client sockets bpf: selftests: Add defrag selftests include/linux/netfilter.h | 10 + include/uapi/linux/bpf.h | 5 + net/ipv4/netfilter/nf_defrag_ipv4.c | 17 +- net/ipv6/netfilter/nf_defrag_ipv6_hooks.c | 11 + net/netfilter/core.c | 6 + net/netfilter/nf_bpf_link.c | 116 ++++++- tools/include/uapi/linux/bpf.h | 5 + tools/testing/selftests/bpf/Makefile | 4 +- .../selftests/bpf/generate_udp_fragments.py | 90 ++++++ .../selftests/bpf/ip_check_defrag_frags.h | 57 ++++ tools/testing/selftests/bpf/network_helpers.c | 26 +- tools/testing/selftests/bpf/network_helpers.h | 3 + .../bpf/prog_tests/ip_check_defrag.c | 283 ++++++++++++++++++ .../selftests/bpf/progs/ip_check_defrag.c | 104 +++++++ 14 files changed, 715 insertions(+), 22 deletions(-) create mode 100755 tools/testing/selftests/bpf/generate_udp_fragments.py create mode 100644 tools/testing/selftests/bpf/ip_check_defrag_frags.h create mode 100644 tools/testing/selftests/bpf/prog_tests/ip_check_defrag.c create mode 100644 tools/testing/selftests/bpf/progs/ip_check_defrag.c -- 2.41.0

2 years, 4 months

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Re: fs/proc/task_mmu: Implement IOCTL for efficient page table scanning

by Michał Mirosław

On Thu, Jul 20, 2023 at 09:28:52PM +0200, Michał Mirosław wrote: > This is a massaged version of patch by Muhammad Usama Anjum [1] > to illustrate my review comments and hopefully push the implementation > efforts closer to conclusion. The changes are: [...] > +static void pagemap_scan_backout_range(struct pagemap_scan_private *p, > + unsigned long addr, unsigned long end) > +{ > + struct page_region *cur_buf = &p->cur_buf; > + > + if (cur_buf->start != addr) { > + cur_buf->end = addr; > + } else { > + cur_buf->start = cur_buf->end = 0; > + } > + > + p->end_addr = 0; Just noticed that this is missing: p->found_pages -= (end - addr) / PAGE_SIZE; > +} [...] Best Regards Michał Mirosław

2 years, 4 months

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[PATCH v2 0/7] KUnit integration for Rust doctests

by Miguel Ojeda

v1: https://lore.kernel.org/rust-for-linux/20230614180837.630180-1-ojeda@kernel… v2: - Rebased on top of v6.5-rc1, which requires a change from `kunit_do_failed_assertion` to `__kunit_do_failed_assertion` (since the former became a macro) and the addition of a call to `__kunit_abort` (since previously the call was done by the old function which we cannot use anymore since it is a macro). (David) - Added prerequisite patch to KUnit header to include `stddef.h` to support the `KUNIT=y` case. (Reported by Boqun) - Added comment on the purpose of `trait FromErrno`. (Martin asked about it) - Simplify code to use `std::fs::write` instead of `write!`, which improves code size too. (Suggested by Alice) - Fix copy-paste type in docs from "error" to "info" and, to make it proper English, copy the `printk` docs style, i.e. from "info" to "info-level message" -- and same for the "error" one. (Miguel) - Swap `FILE` and `LINE` `static`s to keep the same order as done elsewhere. (Miguel) - Rename config option from `RUST_KERNEL_KUNIT_TEST` to `RUST_KERNEL_DOCTESTS` (and update its title), so that we can use the former for the "normal" (i.e. non-doctests, e.g. `#[test]` ones) tests in the future. (David) - Follow the syntax proposed for declaring test metadata in the KTAP v2 spec, which may also get used for the KUnit test attributes API. Thus, instead of "# Doctest from line {line}", use "# {test_name}.location: {file}.{line}", which ideally will allow to migrate to a KUnit attribute later. This is done in all cases, i.e. when the tests succeeds, because it may be useful for users running KUnit manually, or when passing `--raw_output` to `kunit.py`. (David) David: I used "location" instead of your suggested "line" alone, in order to have both in a single line, which looked nice and closer to the "ASSERTION FAILURE" case/line, since now we do have the original file (please see below). - Figure out the original line. This is done by deploying an anchor so that the difference in lines between the beginning of the test and the assert, in the generated file, can be computed. Then, we offset the line number of the original test, which is given by `rustdoc`. (developed by Boqun) - Figure out the original file. This is done by walking the filesystem, checking directory prefixes to reduce the amount of combinations to check, and it is only done once per file (rather than per test). Ambiguities are detected and reported. It does limit the filenames (module names) we can use, but it is unlikely we will hit it soon and this should be temporary anyway until `rustdoc` provides us with the real path. (Miguel) Tested with both in-tree and `O=` builds, but I would appreciate extra testing on this one, including via the `kunit.py` script. - The three last items combined means that we now see this output even for successful cases: # rust_doctest_kernel_sync_locked_by_rs_0.location: rust/kernel/sync/locked_by.rs:28 ok 53 rust_doctest_kernel_sync_locked_by_rs_0 Which basically gives the user all the information they need to go back to the source code of the doctest, while keeping them fairly stable for bisection, and while avoiding to require users to write test names manually. (David + Boqun + Miguel) David: from what I saw in v2 of the RFC for the test attributes API, the syntax still contains the test name when it is not a suite, so I followed that, but if you prefer to omit it, please feel free to do so (for me either way it is fine, and if this is the expected attribute syntax, I guess it is worth to follow it to make migration easier later on): # location: rust/kernel/sync/locked_by.rs:28 ok 53 rust_doctest_kernel_sync_locked_by_rs_0 - Collected `Reviewed-by`s and `Tested-by`s, except for the main commit due to the substantial changes. Miguel Ojeda (7): kunit: test-bug.h: include `stddef.h` for `NULL` rust: init: make doctests compilable/testable rust: str: make doctests compilable/testable rust: sync: make doctests compilable/testable rust: types: make doctests compilable/testable rust: support running Rust documentation tests as KUnit ones MAINTAINERS: add Rust KUnit files to the KUnit entry MAINTAINERS | 2 + include/kunit/test-bug.h | 2 + lib/Kconfig.debug | 13 ++ rust/.gitignore | 2 + rust/Makefile | 29 ++++ rust/bindings/bindings_helper.h | 1 + rust/helpers.c | 7 + rust/kernel/init.rs | 26 +-- rust/kernel/kunit.rs | 163 +++++++++++++++++++ rust/kernel/lib.rs | 2 + rust/kernel/str.rs | 4 +- rust/kernel/sync/arc.rs | 9 +- rust/kernel/sync/lock/mutex.rs | 1 + rust/kernel/sync/lock/spinlock.rs | 1 + rust/kernel/types.rs | 6 +- scripts/.gitignore | 2 + scripts/Makefile | 4 + scripts/rustdoc_test_builder.rs | 72 +++++++++ scripts/rustdoc_test_gen.rs | 260 ++++++++++++++++++++++++++++++ 19 files changed, 591 insertions(+), 15 deletions(-) create mode 100644 rust/kernel/kunit.rs create mode 100644 scripts/rustdoc_test_builder.rs create mode 100644 scripts/rustdoc_test_gen.rs base-commit: 06c2afb862f9da8dc5efa4b6076a0e48c3fbaaa5 -- 2.41.0

2 years, 4 months

4
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[PATCH 0/3] arm64/fpsimd: Fix use after free in SME when changing SVE VL

by Mark Brown

This series fixes an issue which David Spickett found where if we change the SVE VL while SME is in use we can end up attempting to save state to an unallocated buffer and adds testing coverage for that plus a bit more coverage of VL changes, just for paranioa. Signed-off-by: Mark Brown <broonie(a)kernel.org> --- Mark Brown (3): arm64/fpsimd: Ensure SME storage is allocated after SVE VL changes kselftest/arm64: Add a test case for SVE VL changes with SME active kselftest/arm64: Validate that changing one VL type does not affect another arch/arm64/kernel/fpsimd.c | 32 +++++-- tools/testing/selftests/arm64/fp/vec-syscfg.c | 127 +++++++++++++++++++++++++- 2 files changed, 148 insertions(+), 11 deletions(-) --- base-commit: 06c2afb862f9da8dc5efa4b6076a0e48c3fbaaa5 change-id: 20230713-arm64-fix-sve-sme-vl-change-60eb1fa6a707 Best regards, -- Mark Brown <broonie(a)kernel.org>

2 years, 4 months

3
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[PATCH v2 0/3] drivers: base: Add tests showing devm handling inconsistencies

by Maxime Ripard

Hi, This follows the discussion here: https://lore.kernel.org/linux-kselftest/20230324123157.bbwvfq4gsxnlnfwb@hou… This shows a couple of inconsistencies with regard to how device-managed resources are cleaned up. Basically, devm resources will only be cleaned up if the device is attached to a bus and bound to a driver. Failing any of these cases, a call to device_unregister will not end up in the devm resources being released. We had to work around it in DRM to provide helpers to create a device for kunit tests, but the current discussion around creating similar, generic, helpers for kunit resumed interest in fixing this. This can be tested using the command: ./tools/testing/kunit/kunit.py run --kunitconfig=drivers/base/test/ I added the fix David suggested back in that discussion which does fix the tests. The SoB is missing, since David didn't provide it back then. Let me know what you think, Maxime Signed-off-by: Maxime Ripard <maxime(a)cerno.tech> --- Changes in v2: - Use an init function - Document the tests - Add a fix for the bugs - Link to v1: https://lore.kernel.org/r/20230329-kunit-devm-inconsistencies-test-v1-0-c33… --- David Gow (1): drivers: base: Free devm resources when unregistering a device Maxime Ripard (2): drivers: base: Add basic devm tests for root devices drivers: base: Add basic devm tests for platform devices drivers/base/core.c | 11 ++ drivers/base/test/.kunitconfig | 2 + drivers/base/test/Kconfig | 4 + drivers/base/test/Makefile | 3 + drivers/base/test/platform-device-test.c | 220 +++++++++++++++++++++++++++++++ drivers/base/test/root-device-test.c | 108 +++++++++++++++ 6 files changed, 348 insertions(+) --- base-commit: 53cdf865f90ba922a854c65ed05b519f9d728424 change-id: 20230329-kunit-devm-inconsistencies-test-5e5a7d01e60d Best regards, -- Maxime Ripard <mripard(a)kernel.org>

2 years, 4 months

2
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[PATCH v5 0/6] KVM: selftests: Improve PMU event filter settings and add test cases

by Jinrong Liang

Hi, This patch series aims to improve the PMU event filter settings with a cleaner and more organized structure and adds several test cases related to PMU event filters. These changes help to ensure that KVM's PMU event filter functions as expected in all supported use cases. Any feedback or suggestions are greatly appreciated. Sincerely, Jinrong Liang Changes log: v5: - Add more x86 properties for Intel PMU; - Designated initializer instead of overwrite all members; (Isaku Yamahata) - PMU event filter invalid flag modified to "KVM_PMU_EVENT_FLAGS_VALID_MASK << 1"; (Isaku Yamahata) - sizeof(bitmap) is modified to "sizeof(bitmap) * 8" to represent the number of bits that can be represented by the bitmap variable. (Isaku Yamahata) Previous: https://lore.kernel.org/kvm/20230717062343.3743-1-cloudliang@tencent.com/T/ Jinrong Liang (6): KVM: selftests: Add x86 properties for Intel PMU in processor.h KVM: selftests: Drop the return of remove_event() KVM: selftests: Introduce __kvm_pmu_event_filter to improved event filter settings KVM: selftests: Add test cases for unsupported PMU event filter input values KVM: selftests: Test if event filter meets expectations on fixed counters KVM: selftests: Test gp event filters don't affect fixed event filters .../selftests/kvm/include/x86_64/processor.h | 5 + .../kvm/x86_64/pmu_event_filter_test.c | 317 ++++++++++++------ 2 files changed, 228 insertions(+), 94 deletions(-) base-commit: 88bb466c9dec4f70d682cf38c685324e7b1b3d60 -- 2.39.3

2 years, 4 months

1
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[PATCH v2] kselftest/arm64: Exit streaming mode after collecting signal context

by Mark Brown

When we collect a signal context with one of the SME modes enabled we will have enabled that mode behind the compiler and libc's back so they may issue some instructions not valid in streaming mode, causing spurious failures. For the code prior to issuing the BRK to trigger signal handling we need to stay in streaming mode if we were already there since that's a part of the signal context the caller is trying to collect. Unfortunately this code includes a memset() which is likely to be heavily optimised and is likely to use FP instructions incompatible with streaming mode. We can avoid this happening by open coding the memset(), inserting a volatile assembly statement to avoid the compiler recognising what's being done and doing something in optimisation. This code is not performance critical so the inefficiency should not be an issue. After collecting the context we can simply exit streaming mode, avoiding these issues. Use a full SMSTOP for safety to prevent any issues appearing with ZA. Reported-by: Will Deacon <will(a)kernel.org> Signed-off-by: Mark Brown <broonie(a)kernel.org> --- Changes in v2: - Rebase onto v6.5-rc1. - Link to v1: https://lore.kernel.org/r/20230628-arm64-signal-memcpy-fix-v1-1-db3e0300829… --- .../selftests/arm64/signal/test_signals_utils.h | 28 +++++++++++++++++++++- 1 file changed, 27 insertions(+), 1 deletion(-) diff --git a/tools/testing/selftests/arm64/signal/test_signals_utils.h b/tools/testing/selftests/arm64/signal/test_signals_utils.h index 222093f51b67..db28409fd44b 100644 --- a/tools/testing/selftests/arm64/signal/test_signals_utils.h +++ b/tools/testing/selftests/arm64/signal/test_signals_utils.h @@ -60,13 +60,28 @@ static __always_inline bool get_current_context(struct tdescr *td, size_t dest_sz) { static volatile bool seen_already; + int i; + char *uc = (char *)dest_uc; assert(td && dest_uc); /* it's a genuine invocation..reinit */ seen_already = 0; td->live_uc_valid = 0; td->live_sz = dest_sz; - memset(dest_uc, 0x00, td->live_sz); + + /* + * This is a memset() but we don't want the compiler to + * optimise it into either instructions or a library call + * which might be incompatible with streaming mode. + */ + for (i = 0; i < td->live_sz; i++) { + asm volatile("nop" + : "+m" (*dest_uc) + : + : "memory"); + uc[i] = 0; + } + td->live_uc = dest_uc; /* * Grab ucontext_t triggering a SIGTRAP. @@ -103,6 +118,17 @@ static __always_inline bool get_current_context(struct tdescr *td, : : "memory"); + /* + * If we were grabbing a streaming mode context then we may + * have entered streaming mode behind the system's back and + * libc or compiler generated code might decide to do + * something invalid in streaming mode, or potentially even + * the state of ZA. Issue a SMSTOP to exit both now we have + * grabbed the state. + */ + if (td->feats_supported & FEAT_SME) + asm volatile("msr S0_3_C4_C6_3, xzr"); + /* * If we get here with seen_already==1 it implies the td->live_uc * context has been used to get back here....this probably means --- base-commit: 06c2afb862f9da8dc5efa4b6076a0e48c3fbaaa5 change-id: 20230628-arm64-signal-memcpy-fix-7de3b3c8fa10 Best regards, -- Mark Brown <broonie(a)kernel.org>

2 years, 4 months

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