diff options
| author | Karl Mehltretter <kmehltretter@gmail.com> | 2026-08-08 22:03:12 +0200 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2026-08-24 18:43:33 -0700 |
| commit | 0685630fdccb62dcb0e3f44525a40578da5f6dc8 (patch) | |
| tree | b898214bf9d3221870deb88ec3876946ebb4481e | |
| parent | 0e0ac326c511d514817cc7b6d7741afd59098ce2 (diff) | |
selftests/proc: make proc-maps-race work with READ_IMPLIES_EXEC
test_maps_tearing_from_split times out when READ_IMPLIES_EXEC is set.
This happens by default on pre-ARMv6 CPUs, which lack no-execute support.
split_vma() re-maps the first page with mod_info->prot | PROT_EXEC to make
it differ from its neighbours. With READ_IMPLIES_EXEC the original
mapping is already executable, so no split occurs and the test hangs
waiting for the modifier child.
Use PROT_NONE for the split mapping, which always differs from its
readable neighbours.
Link: https://lore.kernel.org/20260808200312.6326-1-kmehltretter@gmail.com
Fixes: beb69e817246 ("selftests/proc: add /proc/pid/maps tearing from vma split test")
Assisted-by: Codex:gpt-5.6-terra
Signed-off-by: Karl Mehltretter <kmehltretter@gmail.com>
Acked-by: Suren Baghdasaryan <surenb@google.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Jann Horn <jannh@google.com>
Cc: Liam R. Howlett <liam@infradead.org>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
| -rw-r--r-- | tools/testing/selftests/proc/proc-maps-race.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/tools/testing/selftests/proc/proc-maps-race.c b/tools/testing/selftests/proc/proc-maps-race.c index 1026d8c400e1..415eccb70468 100644 --- a/tools/testing/selftests/proc/proc-maps-race.c +++ b/tools/testing/selftests/proc/proc-maps-race.c @@ -490,7 +490,8 @@ static bool query_addr_at(int maps_fd, void *addr, static inline bool split_vma(FIXTURE_DATA(proc_maps_race) *self) { - return mmap(self->mod_info->addr, self->page_size, self->mod_info->prot | PROT_EXEC, + /* PROT_NONE differs from both readable neighbors. */ + return mmap(self->mod_info->addr, self->page_size, PROT_NONE, MAP_PRIVATE | MAP_ANONYMOUS | MAP_FIXED, -1, 0) != MAP_FAILED; } |