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a=ed25519; pk=pfvxvpFUDJV2h2nY0FidLUml22uGLSjByFbM6aqQQws= X-Rspamd-Queue-Id: 883FC40007 X-Rspamd-Server: rspam12 X-Stat-Signature: x6q1b4fid7n4oind9quj74sfr5w9mj9s X-Rspam-User: X-HE-Tag: 1736262898-262320 X-HE-Meta: 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 BiEBENrX Q/jAvlk6iVW57q+rk+uVr39zIOL1saDeLRlKATR9wMPT6iDQAavLRwDnQkG45FyDcdsH7De3xnTLVQ/643PkEsAEii/APSNY8DKaUSi9/leG5ykpZgXhukljGzaNMsktGi77a1qBx8c56qOEEEyq3faFkqWjW/carhGod+1NTBS8E7xQKBYlyCQFBLBSEV5gBqQ+Q/qxBZZ8RBdCudt0HSkPU2fjrC+C3xm76liFBXvKvt+8vS0K7bJEtU+s9Jte2YcHelZhNe3Vc8ebRJ4bnfqc+5NgA2zRtRy0HoibdtuXSF+j+a3Bqb/Kq0uY68ddYF9lk/ekQO/x4Xq79P4ZD/+EG9xxUAcqCb8+9bJgo7Od5QIMZZ/Sz/T2dZvMktXJjYw2O7SoXhPq6mrwH4NqvvgTV+9rdx4ap137fmLb/zqtR30ZO0HtLXv7d/05EvtzdHI9p X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: During the execution of validate_complete_va_space() a lot of memory is on the VM subsystem. When running on a low memory subsystem an OOM may be triggered, when writing to the dump file as the filesystem may also require memory. On my test system with 1100MiB physical memory: Tasks state (memory values in pages): [ pid ] uid tgid total_vm rss rss_anon rss_file rss_shmem pgtables_bytes swapents oom_score_adj name [ 57] 0 57 34359215953 695 256 0 439 1064390656 0 0 virtual_address Out of memory: Killed process 57 (virtual_address) total-vm:137436863812kB, anon-rss:1024kB, file-rss:0kB, shmem-rss:1756kB, UID:0 pgtables:1039444kB oom_score_adj:0 fault_in_iov_iter_readable+0x4a/0xd0 generic_perform_write+0x9c/0x280 shmem_file_write_iter+0x86/0x90 vfs_write+0x29c/0x480 ksys_write+0x6c/0xe0 do_syscall_64+0x9e/0x1a0 entry_SYSCALL_64_after_hwframe+0x77/0x7f Write the dumped data into /dev/null instead which does not require additional memory during write(), making the code simpler as a side-effect. Signed-off-by: Thomas Weißschuh --- tools/testing/selftests/mm/virtual_address_range.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/tools/testing/selftests/mm/virtual_address_range.c b/tools/testing/selftests/mm/virtual_address_range.c index 484f82c7b7c871f82a7d9ec6d6c649f2ab1eb0cd..4042fd878acd702d23da2c3293292de33bd48143 100644 --- a/tools/testing/selftests/mm/virtual_address_range.c +++ b/tools/testing/selftests/mm/virtual_address_range.c @@ -103,10 +103,9 @@ static int validate_complete_va_space(void) FILE *file; int fd; - fd = open("va_dump", O_CREAT | O_WRONLY, 0600); - unlink("va_dump"); + fd = open("/dev/null", O_WRONLY); if (fd < 0) { - ksft_test_result_skip("cannot create or open dump file\n"); + ksft_test_result_skip("cannot create or open /dev/null\n"); ksft_finished(); } @@ -152,7 +151,6 @@ static int validate_complete_va_space(void) while (start_addr + hop < end_addr) { if (write(fd, (void *)(start_addr + hop), 1) != 1) return 1; - lseek(fd, 0, SEEK_SET); hop += MAP_CHUNK_SIZE; }