From e81ee06308379a5f2ededf997bcf17551bce5db7 Mon Sep 17 00:00:00 2001 From: Eric Kim Date: Tue, 18 Aug 2026 12:48:29 +0900 Subject: sched/fair: Reset NUMA fault locality after scan period update When updating the task scan period for NUMA locality checks, update_task_scan_period() checks whether there were no faults or failed migration on the last scan window, at which it prolongs the scan period. However, p->numa_faults_locality, which is used to check for migration failure and number of faults at the previous scan window is not cleared after changing the scan period, which unintentionally increases numa_scan_period up to numa_scan_period_max even when there were no migration failures or no faults at previous scan. Fix this by jumping to the out label on early exit at this case to ensure p->numa_faults_locality is always cleared before returning. Closes: https://lore.kernel.org/all/20250404095354.311156-1-qlsdnjs236@chungbuk.ac.kr/ Reported-by: Binwon Song Signed-off-by: Eric Kim Signed-off-by: Peter Zijlstra (Intel) Cc: stable@vger.kernel.org Link: https://patch.msgid.link/Message-ID: --- kernel/sched/fair.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index b8bd308c2d5b..a42360ca94c3 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -3514,7 +3514,7 @@ static void update_task_scan_period(struct task_struct *p, p->mm->numa_next_scan = jiffies + msecs_to_jiffies(p->numa_scan_period); - return; + goto out; } /* @@ -3558,7 +3558,10 @@ static void update_task_scan_period(struct task_struct *p, p->numa_scan_period = clamp(p->numa_scan_period + diff, task_scan_min(p), task_scan_max(p)); - memset(p->numa_faults_locality, 0, sizeof(p->numa_faults_locality)); + +out: + memset(p->numa_faults_locality, 0, + sizeof(p->numa_faults_locality)); } /* -- cgit v1.2.3