4.19-stable review patch. If anyone has any objections, please let me know. ------------------ From: Dev Jain <dev.jain@xxxxxxx> [ Upstream commit 9ad665ef55eaad1ead1406a58a34f615a7c18b5e ] 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> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- tools/testing/selftests/vm/compaction_test.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/tools/testing/selftests/vm/compaction_test.c b/tools/testing/selftests/vm/compaction_test.c index bcec712508731..cb2db2102dd26 100644 --- a/tools/testing/selftests/vm/compaction_test.c +++ b/tools/testing/selftests/vm/compaction_test.c @@ -102,6 +102,8 @@ int check_compaction(unsigned long mem_free, unsigned int hugepage_size) 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)) { perror("Failed to write 0 to /proc/sys/vm/nr_hugepages\n"); -- 2.43.0