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charset="utf-8" pick_eevdf() may return NULL, which triggers NULL pointer dereference at pick_next_entity(): struct sched_entity *se =3D pick_eevdf(cfs_rq); if (se->sched_delayed) [ 297.371198] Unable to handle kernel NULL pointer dereference at virt= ual address 0000000000000051 [ 297.406112] CPU: 116 UID: 0 PID: 10328 Comm: Grizzly-worker( Tainted= : G W E 6.12.0.adam+ #1 [ 297.597362] Call trace: [ 297.599795] pick_task_fair+0x50/0x150 (P) [ 297.603879] pick_task_fair+0x50/0x150 (L) [ 297.607963] pick_next_task_fair+0x30/0x3c0 [ 297.612134] __pick_next_task+0x4c/0x220 [ 297.616045] pick_next_task+0x44/0x980 [ 297.619782] __schedule+0x3d0/0x628 [ 297.623259] do_task_dead+0x50/0x60 [ 297.626736] do_exit+0x28c/0x410 [ 297.629955] do_group_exit+0x3c/0xa0 [ 297.633518] get_signal+0x8c4/0x8d0 [ 297.636996] do_signal+0x9c/0x270 [ 297.640299] do_notify_resume+0xe0/0x198 [ 297.644212] el0_svc+0xf4/0x170 [ 297.647342] el0t_64_sync_handler+0x10c/0x138 [ 297.651687] el0t_64_sync+0x1ac/0x1b0 [ 297.655339] Code: d503201f 1400002a aa1403e0 97ffda0b (39414401) [ 297.661439] ---[ end trace 0000000000000000 ]--- [ 297.726593] Kernel panic - not syncing: Oops: Fatal exception Signed-off-by: Adam Li --- kernel/sched/fair.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index cd1188b7f3df..d5a3b5589e4e 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -5623,7 +5623,7 @@ pick_next_entity(struct rq *rq, struct cfs_rq *cfs_rq) } =20 struct sched_entity *se =3D pick_eevdf(cfs_rq); - if (se->sched_delayed) { + if (se && se->sched_delayed) { dequeue_entities(rq, se, DEQUEUE_SLEEP | DEQUEUE_DELAYED); /* * Must not reference @se again, see __block_task(). --=20 2.25.1