mirror_ubuntu-kernels/tools/testing
Dev Jain 0104096498 selftests/mm: confirm VA exhaustion without reliance on correctness of mmap()
Currently, VA exhaustion is being checked by passing a hint to mmap() and
expecting it to fail.

While populating the lower VA space, mmap() fails because we have 
exhausted the space.

Then, in validate_lower_address_hint(), because mmap() fails, we
confirm that we have indeed exhausted the space.  There is a circular
logic involved here.

Assume that there is a bug in mmap(), also assume that it exists
independent of whether you pass a hint address or not; that for some
reason it is not able to find a 1GB chunk.  My idea is to assert the
exhaustion against some other method.

This patch makes a stricter test by successful
write() calls from /proc/self/maps to a dump file, confirming that a free
chunk is indeed not available.

[dev.jain@arm.com: replace SZ_1GB with MAP_CHUNK_SIZE, tidy-up]
  Link: https://lkml.kernel.org/r/20240325042653.867055-1-dev.jain@arm.com
Link: https://lkml.kernel.org/r/20240321103522.516097-1-dev.jain@arm.com
Signed-off-by: Dev Jain <dev.jain@arm.com>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-04-25 20:56:01 -07:00
..
crypto/chacha20-s390
cxl cxl: Consolidate dport access_coordinate ->hb_coord and ->sw_coord into ->coord 2024-04-08 08:25:21 -07:00
fault-injection
ktest ktest: force $buildonly = 1 for 'make_warnings_file' test type 2024-03-15 12:36:19 -04:00
kunit linux_kselftest-kunit-fixes-6.9-rc2 2024-03-29 15:35:12 -07:00
memblock mm, treewide: rename MAX_ORDER to MAX_PAGE_ORDER 2024-01-08 15:27:15 -08:00
nvdimm tools/testing/nvdimm: Disable "missing prototypes / declarations" warnings 2024-01-22 10:41:59 -08:00
radix-tree maple_tree: fix warning comparing pointer to 0 2023-12-20 14:48:12 -08:00
scatterlist
selftests selftests/mm: confirm VA exhaustion without reliance on correctness of mmap() 2024-04-25 20:56:01 -07:00
vsock vsock/test: print type for SOCK_SEQPACKET 2024-01-25 16:39:21 -08:00