From: Juri Lelli juri.lelli@redhat.com
[ Upstream commit ce9bc3b27f2a21a7969b41ffb04df8cf61bd1592 ]
syzbot reported the following warning triggered via SYSC_sched_setattr():
WARNING: CPU: 0 PID: 6973 at kernel/sched/deadline.c:593 setup_new_dl_entity /kernel/sched/deadline.c:594 [inline] WARNING: CPU: 0 PID: 6973 at kernel/sched/deadline.c:593 enqueue_dl_entity /kernel/sched/deadline.c:1370 [inline] WARNING: CPU: 0 PID: 6973 at kernel/sched/deadline.c:593 enqueue_task_dl+0x1c17/0x2ba0 /kernel/sched/deadline.c:1441
This happens because the ->dl_boosted flag is currently not initialized by __dl_clear_params() (unlike the other flags) and setup_new_dl_entity() rightfully complains about it.
Initialize dl_boosted to 0.
Fixes: 2d3d891d3344 ("sched/deadline: Add SCHED_DEADLINE inheritance logic") Reported-by: syzbot+5ac8bac25f95e8b221e7@syzkaller.appspotmail.com Signed-off-by: Juri Lelli juri.lelli@redhat.com Signed-off-by: Peter Zijlstra (Intel) peterz@infradead.org Signed-off-by: Ingo Molnar mingo@kernel.org Tested-by: Daniel Wagner dwagner@suse.de Link: https://lkml.kernel.org/r/20200617072919.818409-1-juri.lelli@redhat.com Signed-off-by: Sasha Levin sashal@kernel.org --- kernel/sched/deadline.c | 1 + 1 file changed, 1 insertion(+)
diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c index 08bdee0480b3e..4cb00538a207b 100644 --- a/kernel/sched/deadline.c +++ b/kernel/sched/deadline.c @@ -2693,6 +2693,7 @@ void __dl_clear_params(struct task_struct *p) dl_se->dl_bw = 0; dl_se->dl_density = 0;
+ dl_se->dl_boosted = 0; dl_se->dl_throttled = 0; dl_se->dl_yielded = 0; dl_se->dl_non_contending = 0;