diff options
| author | Lorenzo Stoakes <lorenzo.stoakes@oracle.com> | 2025-04-25 19:24:36 +0300 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2025-05-08 09:39:40 +0300 |
| commit | a8efadda8649506e80d256cc09656acc0783df2b (patch) | |
| tree | 855eeb84a68ac9c0e5ea387be12939373ebfe59b | |
| parent | fcaf3b2683b05a9684acdebda706a12025a6927a (diff) | |
| download | linux-a8efadda8649506e80d256cc09656acc0783df2b.tar.xz | |
tools/testing/selftests: fix guard region test tmpfs assumption
The current implementation of the guard region tests assume that /tmp is
mounted as tmpfs, that is shmem.
This isn't always the case, and at least one instance of a spurious test
failure has been reported as a result.
This assumption is unsafe, rushed and silly - and easily remedied by
simply using memfd, so do so.
We also have to fixup the readonly_file test to explicitly only be
applicable to file-backed cases.
Link: https://lkml.kernel.org/r/20250425162436.564002-1-lorenzo.stoakes@oracle.com
Fixes: 272f37d3e99a ("tools/selftests: expand all guard region tests to file-backed")
Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Reported-by: Ryan Roberts <ryan.roberts@arm.com>
Closes: https://lore.kernel.org/linux-mm/a2d2766b-0ab4-437b-951a-8595a7506fe9@arm.com/
Reviewed-by: Ryan Roberts <ryan.roberts@arm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
| -rw-r--r-- | tools/testing/selftests/mm/guard-regions.c | 16 |
1 files changed, 10 insertions, 6 deletions
diff --git a/tools/testing/selftests/mm/guard-regions.c b/tools/testing/selftests/mm/guard-regions.c index b3d0e2771096..eba43ead13ae 100644 --- a/tools/testing/selftests/mm/guard-regions.c +++ b/tools/testing/selftests/mm/guard-regions.c @@ -271,12 +271,16 @@ FIXTURE_SETUP(guard_regions) self->page_size = (unsigned long)sysconf(_SC_PAGESIZE); setup_sighandler(); - if (variant->backing == ANON_BACKED) + switch (variant->backing) { + case ANON_BACKED: return; - - self->fd = open_file( - variant->backing == SHMEM_BACKED ? "/tmp/" : "", - self->path); + case LOCAL_FILE_BACKED: + self->fd = open_file("", self->path); + break; + case SHMEM_BACKED: + self->fd = memfd_create(self->path, 0); + break; + } /* We truncate file to at least 100 pages, tests can modify as needed. */ ASSERT_EQ(ftruncate(self->fd, 100 * self->page_size), 0); @@ -1696,7 +1700,7 @@ TEST_F(guard_regions, readonly_file) char *ptr; int i; - if (variant->backing == ANON_BACKED) + if (variant->backing != LOCAL_FILE_BACKED) SKIP(return, "Read-only test specific to file-backed"); /* Map shared so we can populate with pattern, populate it, unmap. */ |