The patch titled Subject: selftests/mm: compaction_test: fix incorrect write of zero to nr_hugepages has been added to the -mm mm-hotfixes-unstable branch. Its filename is selftests-mm-compaction_test-fix-incorrect-write-of-zero-to-nr_hugepages.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/selftests-mm-compaction_test-fix-incorrect-write-of-zero-to-nr_hugepages.patch This patch will later appear in the mm-hotfixes-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via the mm-everything branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there every 2-3 working days ------------------------------------------------------ From: Dev Jain <dev.jain@xxxxxxx> Subject: selftests/mm: compaction_test: fix incorrect write of zero to nr_hugepages Date: Tue, 21 May 2024 13:13:57 +0530 Currently, the test tries to set nr_hugepages to zero, but that is not actually done because the file offset is not reset after read(). Fix that using lseek(). Link: https://lkml.kernel.org/r/20240521074358.675031-3-dev.jain@xxxxxxx Fixes: bd67d5c15cc1 ("Test compaction of mlocked memory") Signed-off-by: Dev Jain <dev.jain@xxxxxxx> Cc: <stable@xxxxxxxxxxxxxxx> Cc: Anshuman Khandual <anshuman.khandual@xxxxxxx> Cc: Shuah Khan <shuah@xxxxxxxxxx> Cc: Sri Jayaramappa <sjayaram@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- tools/testing/selftests/mm/compaction_test.c | 2 ++ 1 file changed, 2 insertions(+) --- a/tools/testing/selftests/mm/compaction_test.c~selftests-mm-compaction_test-fix-incorrect-write-of-zero-to-nr_hugepages +++ a/tools/testing/selftests/mm/compaction_test.c @@ -108,6 +108,8 @@ int check_compaction(unsigned long mem_f goto close_fd; } + lseek(fd, 0, SEEK_SET); + /* Start with the initial condition of 0 huge pages*/ if (write(fd, "0", sizeof(char)) != sizeof(char)) { ksft_print_msg("Failed to write 0 to /proc/sys/vm/nr_hugepages: %s\n", _ Patches currently in -mm which might be from dev.jain@xxxxxxx are selftests-mm-compaction_test-fix-bogus-test-success-on-aarch64.patch selftests-mm-compaction_test-fix-incorrect-write-of-zero-to-nr_hugepages.patch selftests-mm-compaction_test-fix-bogus-test-success-and-reduce-probability-of-oom-killer-invocation.patch