October 2024 - Linux-kselftest-mirror

[PATCH bpf-next v3 0/2] Support eliding map lookup nullness

by Daniel Xu

This patch allows progs to elide a null check on statically known map lookup keys. In other words, if the verifier can statically prove that the lookup will be in-bounds, allow the prog to drop the null check. This is useful for two reasons: 1. Large numbers of nullness checks (especially when they cannot fail) unnecessarily pushes prog towards BPF_COMPLEXITY_LIMIT_JMP_SEQ. 2. It forms a tighter contract between programmer and verifier. For (1), bpftrace is starting to make heavier use of percpu scratch maps. As a result, for user scripts with large number of unrolled loops, we are starting to hit jump complexity verification errors. These percpu lookups cannot fail anyways, as we only use static key values. Eliding nullness probably results in less work for verifier as well. For (2), percpu scratch maps are often used as a larger stack, as the currrent stack is limited to 512 bytes. In these situations, it is desirable for the programmer to express: "this lookup should never fail, and if it does, it means I messed up the code". By omitting the null check, the programmer can "ask" the verifier to double check the logic. Changes in v3: * Check if stack is (erroneously) growing upwards * Mention in commit message why existing tests needed change Changes in v2: * Added a check for when R2 is not a ptr to stack * Added a check for when stack is uninitialized (no stack slot yet) * Updated existing tests to account for null elision * Added test case for when R2 can be both const and non-const Daniel Xu (2): bpf: verifier: Support eliding map lookup nullness bpf: selftests: verifier: Add nullness elision tests kernel/bpf/verifier.c | 67 ++++++- tools/testing/selftests/bpf/progs/iters.c | 14 +- .../selftests/bpf/progs/map_kptr_fail.c | 2 +- .../bpf/progs/verifier_array_access.c | 166 ++++++++++++++++++ .../selftests/bpf/progs/verifier_map_in_map.c | 2 +- .../testing/selftests/bpf/verifier/map_kptr.c | 2 +- 6 files changed, 242 insertions(+), 11 deletions(-) -- 2.46.0

11 months

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kselftest/fixes build: 6 builds: 2 failed, 4 passed, 1 warning (v6.12-rc1-7-g160c826b4dd0d)

by kernelci.org bot

kselftest/fixes build: 6 builds: 2 failed, 4 passed, 1 warning (v6.12-rc1-7-g160c826b4dd0d) Full Build Summary: https://kernelci.org/build/kselftest/branch/fixes/kernel/v6.12-rc1-7-g160c8… Tree: kselftest Branch: fixes Git Describe: v6.12-rc1-7-g160c826b4dd0d Git Commit: 160c826b4dd0d570f0f51cf002cb49bda807e9f5 Git URL: https://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest.git Built: 4 unique architectures Build Failures Detected: arm64: defconfig+kselftest+arm64-chromebook: (clang-16) FAIL defconfig+kselftest+arm64-chromebook: (gcc-12) FAIL Warnings Detected: arm64: arm: i386: x86_64: x86_64_defconfig+kselftest (clang-16): 1 warning Warnings summary: 1 vmlinux.o: warning: objtool: set_ftrace_ops_ro+0x23: relocation to !ENDBR: .text+0x14fd19 ================================================================================ Detailed per-defconfig build reports: -------------------------------------------------------------------------------- defconfig+kselftest+arm64-chromebook (arm64, gcc-12) — FAIL, 0 errors, 0 warnings, 0 section mismatches -------------------------------------------------------------------------------- defconfig+kselftest+arm64-chromebook (arm64, clang-16) — FAIL, 0 errors, 0 warnings, 0 section mismatches -------------------------------------------------------------------------------- i386_defconfig+kselftest (i386, gcc-12) — PASS, 0 errors, 0 warnings, 0 section mismatches -------------------------------------------------------------------------------- multi_v7_defconfig+kselftest (arm, gcc-12) — PASS, 0 errors, 0 warnings, 0 section mismatches -------------------------------------------------------------------------------- x86_64_defconfig+kselftest (x86_64, clang-16) — PASS, 0 errors, 1 warning, 0 section mismatches Warnings: vmlinux.o: warning: objtool: set_ftrace_ops_ro+0x23: relocation to !ENDBR: .text+0x14fd19 -------------------------------------------------------------------------------- x86_64_defconfig+kselftest (x86_64, gcc-12) — PASS, 0 errors, 0 warnings, 0 section mismatches --- For more info write to <info(a)kernelci.org>

11 months

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[PATCH v3 0/2] Exposing nice CPU usage to userspace

by Joshua Hahn

From: Joshua Hahn <joshua.hahn6(a)gmail.com> v2 -> v3: Signed-off-by & renamed subject for clarity. v1 -> v2: Edited commit messages for clarity. Niced CPU usage is a metric reported in host-level /prot/stat, but is not reported in cgroup-level statistics in cpu.stat. However, when a host contains multiple tasks across different workloads, it becomes difficult to gauge how much of the task is being spent on niced processes based on /proc/stat alone, since host-level metrics do not provide this cgroup-level granularity. Exposing this metric will allow users to accurately probe the niced CPU metric for each workload, and make more informed decisions when directing higher priority tasks. Joshua Hahn (2): Tracking cgroup-level niced CPU time Selftests for niced CPU statistics include/linux/cgroup-defs.h | 1 + kernel/cgroup/rstat.c | 16 ++++- tools/testing/selftests/cgroup/test_cpu.c | 72 +++++++++++++++++++++++ 3 files changed, 86 insertions(+), 3 deletions(-) -- 2.43.5

11 months

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[PATCH] KVM: selftests: Fix build on architectures other than x86_64

by Mark Brown

The recent addition of support for testing with the x86 specific quirk KVM_X86_QUIRK_SLOT_ZAP_ALL disabled in the generic memslot tests broke the build of the KVM selftests for all other architectures: In file included from include/kvm_util.h:8, from include/memstress.h:13, from memslot_modification_stress_test.c:21: memslot_modification_stress_test.c: In function ‘main’: memslot_modification_stress_test.c:176:38: error: ‘KVM_X86_QUIRK_SLOT_ZAP_ALL’ undeclared (first use in this function) 176 | KVM_X86_QUIRK_SLOT_ZAP_ALL); | ^~~~~~~~~~~~~~~~~~~~~~~~~~ Add __x86_64__ guard defines to avoid building the relevant code on other architectures. Fixes: 61de4c34b51c ("KVM: selftests: Test memslot move in memslot_perf_test with quirk disabled") Fixes: 218f6415004a ("KVM: selftests: Allow slot modification stress test with quirk disabled") Reported-by: Aishwarya TCV <aishwarya.tcv(a)arm.com> Signed-off-by: Mark Brown <broonie(a)kernel.org> --- This is obviously disruptive for testing of KVM changes on non-x86 architectures. --- tools/testing/selftests/kvm/memslot_modification_stress_test.c | 2 ++ tools/testing/selftests/kvm/memslot_perf_test.c | 6 ++++++ 2 files changed, 8 insertions(+) diff --git a/tools/testing/selftests/kvm/memslot_modification_stress_test.c b/tools/testing/selftests/kvm/memslot_modification_stress_test.c index e3343f0df9e1..c81a84990eab 100644 --- a/tools/testing/selftests/kvm/memslot_modification_stress_test.c +++ b/tools/testing/selftests/kvm/memslot_modification_stress_test.c @@ -169,12 +169,14 @@ int main(int argc, char *argv[]) case 'i': p.nr_iterations = atoi_positive("Number of iterations", optarg); break; +#ifdef __x86_64__ case 'q': p.disable_slot_zap_quirk = true; TEST_REQUIRE(kvm_check_cap(KVM_CAP_DISABLE_QUIRKS2) & KVM_X86_QUIRK_SLOT_ZAP_ALL); break; +#endif case 'h': default: help(argv[0]); diff --git a/tools/testing/selftests/kvm/memslot_perf_test.c b/tools/testing/selftests/kvm/memslot_perf_test.c index 893366982f77..989ffe0d047f 100644 --- a/tools/testing/selftests/kvm/memslot_perf_test.c +++ b/tools/testing/selftests/kvm/memslot_perf_test.c @@ -113,7 +113,9 @@ static_assert(ATOMIC_BOOL_LOCK_FREE == 2, "atomic bool is not lockless"); static sem_t vcpu_ready; static bool map_unmap_verify; +#ifdef __x86_64__ static bool disable_slot_zap_quirk; +#endif static bool verbose; #define pr_info_v(...) \ @@ -579,8 +581,10 @@ static bool test_memslot_move_prepare(struct vm_data *data, uint32_t guest_page_size = data->vm->page_size; uint64_t movesrcgpa, movetestgpa; +#ifdef __x86_64__ if (disable_slot_zap_quirk) vm_enable_cap(data->vm, KVM_CAP_DISABLE_QUIRKS2, KVM_X86_QUIRK_SLOT_ZAP_ALL); +#endif movesrcgpa = vm_slot2gpa(data, data->nslots - 1); @@ -971,11 +975,13 @@ static bool parse_args(int argc, char *argv[], case 'd': map_unmap_verify = true; break; +#ifdef __x86_64__ case 'q': disable_slot_zap_quirk = true; TEST_REQUIRE(kvm_check_cap(KVM_CAP_DISABLE_QUIRKS2) & KVM_X86_QUIRK_SLOT_ZAP_ALL); break; +#endif case 's': targs->nslots = atoi_paranoid(optarg); if (targs->nslots <= 1 && targs->nslots != -1) { --- base-commit: 9852d85ec9d492ebef56dc5f229416c925758edc change-id: 20240930-kvm-build-breakage-a542f46d78f9 Best regards, -- Mark Brown <broonie(a)kernel.org>

11 months

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[PATCH] selftest: hid: add missing run-hid-tools-tests.sh

by Yun Lu

The HID test cases actually run tests using the run-hid-tools-tests.sh script. However, if installed with "make install", the run-hid-tools-tests.sh script will not be copied over, resulting in the following error message. make -C tools/testing/selftests/ TARGETS=hid install \ INSTALL_PATH=$KSFT_INSTALL_PATH cd $KSFT_INSTALL_PATH ./run_kselftest.sh -c hid selftests: hid: hid-core.sh bash: ./run-hid-tools-tests.sh: No such file or directory So add the run-hid-tools-tests.sh script to the TEST_FILES in the Makefile. Signed-off-by: Yun Lu <luyun(a)kylinos.cn> --- tools/testing/selftests/hid/Makefile | 2 ++ 1 file changed, 2 insertions(+) diff --git a/tools/testing/selftests/hid/Makefile b/tools/testing/selftests/hid/Makefile index 72be55ac4bdf..38ae31bb07b5 100644 --- a/tools/testing/selftests/hid/Makefile +++ b/tools/testing/selftests/hid/Makefile @@ -17,6 +17,8 @@ TEST_PROGS += hid-tablet.sh TEST_PROGS += hid-usb_crash.sh TEST_PROGS += hid-wacom.sh +TEST_FILES := run-hid-tools-tests.sh + CXX ?= $(CROSS_COMPILE)g++ HOSTPKG_CONFIG := pkg-config -- 2.27.0

11 months

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[PATCH] selftests: vDSO: align getrandom states to cache line

by Jason A. Donenfeld

This prevents false sharing, which makes a large difference on machines with several NUMA nodes, such as on a dual socket Intel(R) Xeon(R) Gold 6338 CPU @ 2.00GHz, where the "bench-multi" test goes from 2.7s down to 1.9s. While this is just test code, it also forms the basis of how folks will wind up implementing this in libraries, so we should implement this simple cache alignment improvement here. Suggested-by: Florian Weimer <fweimer(a)redhat.com> Cc: Adhemerval Zanella <adhemerval.zanella(a)linaro.org> Signed-off-by: Jason A. Donenfeld <Jason(a)zx2c4.com> --- tools/testing/selftests/vDSO/vdso_test_getrandom.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/tools/testing/selftests/vDSO/vdso_test_getrandom.c b/tools/testing/selftests/vDSO/vdso_test_getrandom.c index 72a1d9b43a84..e5e83dbec589 100644 --- a/tools/testing/selftests/vDSO/vdso_test_getrandom.c +++ b/tools/testing/selftests/vDSO/vdso_test_getrandom.c @@ -59,10 +59,12 @@ static void *vgetrandom_get_state(void) size_t page_size = getpagesize(); size_t new_cap; size_t alloc_size, num = sysconf(_SC_NPROCESSORS_ONLN); /* Just a decent heuristic. */ + size_t state_size_aligned, cache_line_size = sysconf(_SC_LEVEL1_DCACHE_LINESIZE) ?: 1; void *new_block, *new_states; - alloc_size = (num * vgrnd.params.size_of_opaque_state + page_size - 1) & (~(page_size - 1)); - num = (page_size / vgrnd.params.size_of_opaque_state) * (alloc_size / page_size); + state_size_aligned = (vgrnd.params.size_of_opaque_state + cache_line_size - 1) & (~(cache_line_size - 1)); + alloc_size = (num * state_size_aligned + page_size - 1) & (~(page_size - 1)); + num = (page_size / state_size_aligned) * (alloc_size / page_size); new_block = mmap(0, alloc_size, vgrnd.params.mmap_prot, vgrnd.params.mmap_flags, -1, 0); if (new_block == MAP_FAILED) goto out; @@ -78,7 +80,7 @@ static void *vgetrandom_get_state(void) if (((uintptr_t)new_block & (page_size - 1)) + vgrnd.params.size_of_opaque_state > page_size) new_block = (void *)(((uintptr_t)new_block + page_size - 1) & (~(page_size - 1))); vgrnd.states[i] = new_block; - new_block += vgrnd.params.size_of_opaque_state; + new_block += state_size_aligned; } vgrnd.len = num; goto success; -- 2.46.0

11 months

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[RFC PATCH 0/3] introduce PIDFD_SELF

by Lorenzo Stoakes

If you wish to utilise a pidfd interface to refer to the current process (from the point of view of userland - from the kernel point of view - the thread group leader), it is rather cumbersome, requiring something like: int pidfd = pidfd_open(getpid(), 0); ... close(pidfd); Or the equivalent call opening /proc/self. It is more convenient to use a sentinel value to indicate to an interface that accepts a pidfd that we simply wish to refer to the current process. This series introduces such a sentinel, PIDFD_SELF, which can be passed as the pidfd in this instance rather than having to establish a dummy fd for this purpose. The only pidfd interface where this is particularly useful is process_madvise(), which provides the motivation for this series. However, as this is a general interface, we ensure that all pidfd interfaces can handle this correctly. We ensure that pidfd_send_signal() and pidfd_getfd() work correctly, and assert as much in selftests. All other interfaces except setns() will work implicitly with this new interface, however it doesn't make sense to test waitid(P_PIDFD, ...) as waiting on ourselves is a blocking operation. In the case of setns() we explicitly disallow use of PIDFD_SELF as it doesn't make sense to obtain the namespaces of our own process, and it would require work to implement this functionality there that would be of no use. We also do not provide the ability to utilise PIDFD_SELF in ordinary fd operations such as open() or poll(), as this would require extensive work and be of no real use. Lorenzo Stoakes (3): pidfd: refactor pidfd_get_pid/to_pid() and de-duplicate pid lookup pidfd: add PIDFD_SELF sentinel to refer to own process selftests: pidfd: add tests for PIDFD_SELF include/linux/pid.h | 43 +++++++++++- include/uapi/linux/pidfd.h | 3 + kernel/exit.c | 3 +- kernel/nsproxy.c | 1 + kernel/pid.c | 70 +++++++++++++------ kernel/signal.c | 26 ++----- tools/testing/selftests/pidfd/pidfd.h | 5 ++ .../selftests/pidfd/pidfd_getfd_test.c | 38 ++++++++++ .../selftests/pidfd/pidfd_setns_test.c | 6 ++ tools/testing/selftests/pidfd/pidfd_test.c | 13 ++++ 10 files changed, 165 insertions(+), 43 deletions(-) -- 2.46.2

11 months

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Re: [PATCH v2 1/2] exec: add a flag for "reasonable" execveat() comm

by Eric W. Biederman

"Eric W. Biederman" <ebiederm(a)xmission.com> writes: > Kees Cook <kees(a)kernel.org> writes: >> I'm not super comfortable doing this regardless of bprm->fdpath; that >> seems like too many cases getting changed. Can we just leave it as >> depending on bprm->fdpath? I was recommending that because I did not expect that there was any widespread usage of aliasing of binary names using symlinks. I realized today that on debian there are many aliases of binaries created with the /etc/alternatives mechanism. So there is much wider exposure to problems than I would have supposed. So I remove any objections to making the new code conditional on bprm->fdpath. Eric

11 months

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[PATCH net v4] selftests: net: no_forwarding: fix VID for $swp2 in one_bridge_two_pvids() test

by Kacper Ludwinski

Currently, the second bridge command overwrites the first one. Fix this by adding this VID to the interface behind $swp2. The one_bridge_two_pvids() test intends to check that there is no leakage of traffic between bridge ports which have a single VLAN - the PVID VLAN. Because of a typo, port $swp1 is configured with a PVID twice (second command overwrites first), and $swp2 isn't configured at all (and since the bridge vlan_default_pvid property is set to 0, this port will not have a PVID at all, so it will drop all untagged and priority-tagged traffic). So, instead of testing the configuration that was intended, we are testing a different one, where one port has PVID 2 and the other has no PVID. This incorrect version of the test should also pass, but is ineffective for its purpose, so fix the typo. This typo has an impact on results of the test results, potentially leading to wrong conclusions regarding the functionality of a network device. Fixes: 476a4f05d9b8 ("selftests: forwarding: add a no_forwarding.sh test") Reviewed-by: Hangbin Liu <liuhangbin(a)gmail.com> Reviewed-by: Shuah Khan <skhan(a)linuxfoundation.org> Signed-off-by: Kacper Ludwinski <kac.ludwinski(a)icloud.com> --- tools/testing/selftests/net/forwarding/no_forwarding.sh | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) v4: - Add revision history od this patch - Add "Reviewed-by:" - Limit number of characters in commit to 80 - Add impact explanation to commit message v3: - Edit commit message - Add missing Signed-off-by - Link: https://lore.kernel.org/linux-kselftest/20240927112824.339-1-kac.ludwinski@… v2: - Add missing CCs - Fix typo in commit message - Add target name - Link: https://lore.kernel.org/linux-kselftest/fQknN_r6POzmrp8UVjyA3cknLnB1HB9I_jf… v1: - Link: https://lore.kernel.org/linux-kselftest/20240925050539.1906-1-kacper@ludwin… diff --git a/tools/testing/selftests/net/forwarding/no_forwarding.sh b/tools/testing/selftests/net/forwarding/no_forwarding.sh index 9e677aa64a06..694ece9ba3a7 100755 --- a/tools/testing/selftests/net/forwarding/no_forwarding.sh +++ b/tools/testing/selftests/net/forwarding/no_forwarding.sh @@ -202,7 +202,7 @@ one_bridge_two_pvids() ip link set $swp2 master br0 bridge vlan add dev $swp1 vid 1 pvid untagged - bridge vlan add dev $swp1 vid 2 pvid untagged + bridge vlan add dev $swp2 vid 2 pvid untagged run_test "Switch ports in VLAN-aware bridge with different PVIDs" -- 2.43.0

11 months

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[PATCH v1 0/2] selftests/mm: hugetlb_fault_after_madv improvements

by David Hildenbrand

Mario brought to my attention that the hugetlb_fault_after_madv test is currently always skipped on s390x. Let's adjust the test to be independent of the default hugetlb page size and while at it, also improve the test output. Cc: Andrew Morton <akpm(a)linux-foundation.org> Cc: Shuah Khan <shuah(a)kernel.org> Cc: Mario Casquero <mcasquer(a)redhat.com> Cc: Breno Leitao <leitao(a)debian.org> David Hildenbrand (2): selftests/mm: hugetlb_fault_after_madv: use default hguetlb page size selftests/mm: hugetlb_fault_after_madv: improve test output .../selftests/mm/hugetlb_fault_after_madv.c | 48 ++++++++++++++++--- 1 file changed, 42 insertions(+), 6 deletions(-) -- 2.46.1

11 months

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Linux-kselftest-mirror October 2024