+ selftests-mm-compaction_test-fix-incorrect-write-of-zero-to-nr_hugepages.patch added to mm-hotfixes-unstable branch

+ selftests-mm-compaction_test-fix-incorrect-write-of-zero-to-nr_hugepages.patch added to mm-hotfixes-unstable branch

[Andrew Morton]

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

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------------------------------------------------------
From: Dev Jain <dev.jain@arm.com>
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@arm.com
Fixes: bd67d5c15cc1 ("Test compaction of mlocked memory")
Signed-off-by: Dev Jain <dev.jain@arm.com>
Cc: <stable@vger.kernel.org>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Sri Jayaramappa <sjayaram@akamai.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 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@arm.com 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