4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Song Muchun <smuchun@xxxxxxxxx> [ Upstream commit 9845c49cc9bbb317a0bc9e9cf78d8e09d54c9af0 ] The comment and the code around the update_min_vruntime() call in dequeue_entity() are not in agreement. >From commit: b60205c7c558 ("sched/fair: Fix min_vruntime tracking") I think that we want to update min_vruntime when a task is sleeping/migrating. So, the check is inverted there - fix it. Signed-off-by: Song Muchun <smuchun@xxxxxxxxx> Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Cc: Mike Galbraith <efault@xxxxxx> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Fixes: b60205c7c558 ("sched/fair: Fix min_vruntime tracking") Link: http://lkml.kernel.org/r/20181014112612.2614-1-smuchun@xxxxxxxxx Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- kernel/sched/fair.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -3502,7 +3502,7 @@ dequeue_entity(struct cfs_rq *cfs_rq, st * put back on, and if we advance min_vruntime, we'll be placed back * further than we started -- ie. we'll be penalized. */ - if ((flags & (DEQUEUE_SAVE | DEQUEUE_MOVE)) == DEQUEUE_SAVE) + if ((flags & (DEQUEUE_SAVE | DEQUEUE_MOVE)) != DEQUEUE_SAVE) update_min_vruntime(cfs_rq); }