| Message ID | 20250113-virtual_address_range-tests-v3-1-f4a8e6b7feed@linutronix.de (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | selftests/mm: virtual_address_range: Reduce memory usage and avoid VM_IO access | expand |
On 13/01/25 6:45 pm, Thomas Weißschuh wrote: > When mapping a larger chunk than physical memory is available with > PROT_WRITE and overcommit is disabled, the mapping will fail. > This will prevent the test from running on systems with less then ~1GiB > of memory and triggering an inscrutinable test failure. > As the mappings are never written to anyways, the flag can be removed. > > Fixes: 010409649885 ("selftests/mm: confirm VA exhaustion without reliance on correctness of mmap()") > Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de> > Acked-by: David Hildenbrand <david@redhat.com> > Acked-by: Dev Jain <dev.jain@arm.com> > --- > tools/testing/selftests/mm/virtual_address_range.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/tools/testing/selftests/mm/virtual_address_range.c b/tools/testing/selftests/mm/virtual_address_range.c > index 2a2b69e91950a37999f606847c9c8328d79890c2..ea6ccf49ef4c552f26317c2a40b09bca1a677f8f 100644 > --- a/tools/testing/selftests/mm/virtual_address_range.c > +++ b/tools/testing/selftests/mm/virtual_address_range.c > @@ -166,7 +166,7 @@ int main(int argc, char *argv[]) > ksft_set_plan(1); > > for (i = 0; i < NR_CHUNKS_LOW; i++) { > - ptr[i] = mmap(NULL, MAP_CHUNK_SIZE, PROT_READ | PROT_WRITE, > + ptr[i] = mmap(NULL, MAP_CHUNK_SIZE, PROT_READ, > MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); > > if (ptr[i] == MAP_FAILED) { > @@ -186,7 +186,7 @@ int main(int argc, char *argv[]) > > for (i = 0; i < NR_CHUNKS_HIGH; i++) { > hint = hint_addr(); > - hptr[i] = mmap(hint, MAP_CHUNK_SIZE, PROT_READ | PROT_WRITE, > + hptr[i] = mmap(hint, MAP_CHUNK_SIZE, PROT_READ, > MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); > > if (hptr[i] == MAP_FAILED) > Just noticed a thing: I believe the fix commit you are looking for is 4e5ce33ceb32. My commit which you mention is not responsible for introducing the problem you are solving.
diff --git a/tools/testing/selftests/mm/virtual_address_range.c b/tools/testing/selftests/mm/virtual_address_range.c index 2a2b69e91950a37999f606847c9c8328d79890c2..ea6ccf49ef4c552f26317c2a40b09bca1a677f8f 100644 --- a/tools/testing/selftests/mm/virtual_address_range.c +++ b/tools/testing/selftests/mm/virtual_address_range.c @@ -166,7 +166,7 @@ int main(int argc, char *argv[]) ksft_set_plan(1); for (i = 0; i < NR_CHUNKS_LOW; i++) { - ptr[i] = mmap(NULL, MAP_CHUNK_SIZE, PROT_READ | PROT_WRITE, + ptr[i] = mmap(NULL, MAP_CHUNK_SIZE, PROT_READ, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); if (ptr[i] == MAP_FAILED) { @@ -186,7 +186,7 @@ int main(int argc, char *argv[]) for (i = 0; i < NR_CHUNKS_HIGH; i++) { hint = hint_addr(); - hptr[i] = mmap(hint, MAP_CHUNK_SIZE, PROT_READ | PROT_WRITE, + hptr[i] = mmap(hint, MAP_CHUNK_SIZE, PROT_READ, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); if (hptr[i] == MAP_FAILED)
When mapping a larger chunk than physical memory is available with PROT_WRITE and overcommit is disabled, the mapping will fail. This will prevent the test from running on systems with less then ~1GiB of memory and triggering an inscrutinable test failure. As the mappings are never written to anyways, the flag can be removed. Fixes: 010409649885 ("selftests/mm: confirm VA exhaustion without reliance on correctness of mmap()") Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Acked-by: David Hildenbrand <david@redhat.com> Acked-by: Dev Jain <dev.jain@arm.com> --- tools/testing/selftests/mm/virtual_address_range.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)