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selftests-mm-fix-ternary-operator-precedence-in-ksm_tests.patch removed from -mm tree

merged mm-stable Andrew Morton 1 participant 1 message Aug 5

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The quilt patch titled
Subject: selftests/mm: fix ternary operator precedence in ksm_tests
has been removed from the -mm tree. Its filename was
selftests-mm-fix-ternary-operator-precedence-in-ksm_tests.patch

This patch was dropped because it was merged into the mm-stable branch of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

------------------------------------------------------
From: Sayali Patil <[email protected]>
Subject: selftests/mm: fix ternary operator precedence in ksm_tests
Date: Wed, 8 Jul 2026 12:29:07 +0530

The KSM selftest uses conditional expressions to skip accesses to merge_across_nodes on systems without NUMA support. However, the ternary operator is combined with logical OR without parentheses:

a || numa_available() ? 0 : b || c

Due to operator precedence rules, this is parsed as:

(a || numa_available()) ? 0 : (b || c)

instead of the intended:

a || (numa_available() ? 0 : b) || c

Add parentheses around the conditional expressions to ensure the correct evaluation order.

Link https://lore.kernel.org/ce859430287ed2642848c933a90eb9a69da361f0.1783446924.git.sayalip@linux.ibm.com open here
Fixes 9aa1af954db0 ("selftests: vm: check numa_available() before operating "merge_across_nodes" in ksm_tests")
Signed-off-by Sayali Patil <[email protected]>
Acked-by David Hildenbrand (Arm) <[email protected]>
Cc Dev Jain <[email protected]>
Cc Liam Howlett <[email protected]>
Cc Miaohe Lin <[email protected]>
Cc Michal Hocko <[email protected]>
Cc Oscar Salvador <[email protected]>
Cc "Ritesh Harjani (IBM)" <[email protected]>
Cc Shuah Khan <[email protected]>
Cc Zi Yan <[email protected]>
Signed-off-by Andrew Morton <[email protected]>

---

 tools/testing/selftests/mm/ksm_tests.c |   12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)
tools/testing/selftests/mm/ksm_tests.c renamed from tools/testing/selftests/mm/ksm_tests.c~selftests-mm-fix-ternary-operator-precedence-in-ksm_tests +6 -6
@@ -288,8 +288,8 @@ static bool assert_ksm_pages_count(long
 static int ksm_save_def(struct ksm_sysfs *ksm_sysfs)
 {
 	if (ksm_read_sysfs(KSM_FP("max_page_sharing"), &ksm_sysfs->max_page_sharing) ||
-	    numa_available() ? 0 :
-		ksm_read_sysfs(KSM_FP("merge_across_nodes"), &ksm_sysfs->merge_across_nodes) ||
+	    (numa_available() ? 0 :
+		ksm_read_sysfs(KSM_FP("merge_across_nodes"), &ksm_sysfs->merge_across_nodes)) ||
 	    ksm_read_sysfs(KSM_FP("sleep_millisecs"), &ksm_sysfs->sleep_millisecs) ||
 	    ksm_read_sysfs(KSM_FP("pages_to_scan"), &ksm_sysfs->pages_to_scan) ||
 	    ksm_read_sysfs(KSM_FP("run"), &ksm_sysfs->run) ||

@@ -304,8 +304,8 @@ static int ksm_save_def(struct ksm_sysfs
 static int ksm_restore(struct ksm_sysfs *ksm_sysfs)
 {
 	if (ksm_write_sysfs(KSM_FP("max_page_sharing"), ksm_sysfs->max_page_sharing) ||
-	    numa_available() ? 0 :
-		ksm_write_sysfs(KSM_FP("merge_across_nodes"), ksm_sysfs->merge_across_nodes) ||
+	    (numa_available() ? 0 :
+		ksm_write_sysfs(KSM_FP("merge_across_nodes"), ksm_sysfs->merge_across_nodes)) ||
 	    ksm_write_sysfs(KSM_FP("pages_to_scan"), ksm_sysfs->pages_to_scan) ||
 	    ksm_write_sysfs(KSM_FP("run"), ksm_sysfs->run) ||
 	    ksm_write_sysfs(KSM_FP("sleep_millisecs"), ksm_sysfs->sleep_millisecs) ||

@@ -846,8 +846,8 @@ int main(int argc, char *argv[])
 
 	if (ksm_write_sysfs(KSM_FP("run"), 2) ||
 	    ksm_write_sysfs(KSM_FP("sleep_millisecs"), 0) ||
-	    numa_available() ? 0 :
-		ksm_write_sysfs(KSM_FP("merge_across_nodes"), 1) ||
+	    (numa_available() ? 0 :
+		ksm_write_sysfs(KSM_FP("merge_across_nodes"), 1)) ||
 	    ksm_write_sysfs(KSM_FP("pages_to_scan"), page_count))
 		ksft_exit_fail_msg("Cannot set up KSM tunables\n");

_

Patches currently in -mm which might be from [email protected] are