6.6-stable review patch. If anyone has any objections, please let me know.
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From: Kaushlendra Kumar kaushlendra.kumar@intel.com
commit 7013803444dd3bbbe28fd3360c084cec3057c554 upstream.
The ternary operator in compare_ts() returns 1 when timestamps are equal, causing unstable sorting behavior. Replace with explicit three-way comparison that returns 0 for equal timestamps, ensuring stable qsort ordering and consistent output.
Link: https://lkml.kernel.org/r/20251209044552.3396468-1-kaushlendra.kumar@intel.c... Fixes: 8f9c447e2e2b ("tools/vm/page_owner_sort.c: support sorting pid and time") Signed-off-by: Kaushlendra Kumar kaushlendra.kumar@intel.com Cc: Chongxi Zhao zhaochongxi2019@email.szu.edu.cn Cc: stable@vger.kernel.org Signed-off-by: Andrew Morton akpm@linux-foundation.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- tools/mm/page_owner_sort.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-)
--- a/tools/mm/page_owner_sort.c +++ b/tools/mm/page_owner_sort.c @@ -178,7 +178,11 @@ static int compare_ts(const void *p1, co { const struct block_list *l1 = p1, *l2 = p2;
- return l1->ts_nsec < l2->ts_nsec ? -1 : 1; + if (l1->ts_nsec < l2->ts_nsec) + return -1; + if (l1->ts_nsec > l2->ts_nsec) + return 1; + return 0; }
static int compare_free_ts(const void *p1, const void *p2)