Re: [PATCH] selftests/mm: unpoison pages in memory-failure teardown

From: David Hildenbrand (Arm)

Date: Mon Jul 27 2026 - 08:39:34 EST


On 7/27/26 11:54, Muhammad Usama Anjum wrote:
> The memory-failure tests call cleanup() only after all result checks.
> A failed ASSERT_* invokes fixture teardown and aborts the test, so it
> skips cleanup() and leaves the injected page hardware-poisoned.
>
> Invoke cleanup() from FIXTURE_TEARDOWN() instead. Guard it with
> self->triggered so tests that exit before injection do not try to
> unpoison a page when no injection was attempted. This runs the existing
> HWPoison and HardwareCorrupted checks on both normal and assertion-failure
> paths.
>
> Fixes: ff4ef2fbd101 ("selftests/mm: add memory failure anonymous page test")
> Signed-off-by: Muhammad Usama Anjum <usama.anjum@xxxxxxx>
> ---
> tools/testing/selftests/mm/memory-failure.c | 26 +++++++++------------
> 1 file changed, 11 insertions(+), 15 deletions(-)
>
> diff --git a/tools/testing/selftests/mm/memory-failure.c b/tools/testing/selftests/mm/memory-failure.c
> index 5d00aab31f9b5..eaa8b9bd401a1 100644
> --- a/tools/testing/selftests/mm/memory-failure.c
> +++ b/tools/testing/selftests/mm/memory-failure.c
> @@ -122,13 +122,6 @@ static void teardown_sighandler(void)
> sigaction(SIGBUS, &sa, NULL);
> }
>
> -FIXTURE_TEARDOWN(memory_failure)
> -{
> - close(self->kpageflags_fd);
> - close(self->pagemap_fd);
> - teardown_sighandler();
> -}
> -
> static void prepare(struct __test_metadata *_metadata, FIXTURE_DATA(memory_failure) * self,
> void *vaddr)
> {
> @@ -200,8 +193,7 @@ static void check(struct __test_metadata *_metadata, FIXTURE_DATA(memory_failure
> ASSERT_EQ(pfn_flags & KPF_HWPOISON, KPF_HWPOISON);
> }
>
> -static void cleanup(struct __test_metadata *_metadata, FIXTURE_DATA(memory_failure) * self,
> - void *vaddr)
> +static void cleanup(struct __test_metadata *_metadata, FIXTURE_DATA(memory_failure) * self)
> {
> unsigned long size;
> uint64_t pfn_flags;
> @@ -217,6 +209,16 @@ static void cleanup(struct __test_metadata *_metadata, FIXTURE_DATA(memory_failu
> ASSERT_EQ(size, self->corrupted_size);
> }
>
> +FIXTURE_TEARDOWN(memory_failure)
> +{
> + if (self->triggered)
> + cleanup(_metadata, self);

If the variant->inject(self, addr) fails, self->triggered would already have
been set.

Wouldn't it be cleaner to have a new self->poisoned that we set only after
->inject succeeded?

--
Cheers,

David