Kernel crash when requeue flush request.
It can be reproduced as below:
[ 2.517297] Unable to handle kernel paging request at virtual address ffffffd8071c0b00
...
[ 2.517468] pc : clear_bit+0x18/0x2c
[ 2.517502] lr : sbitmap_queue_clear+0x40/0x228
[ 2.517503] sp : ffffff800832bc60 pstate : 00c00145
...
[ 2.517599] Process ksoftirqd/5 (pid: 51, stack limit = 0xffffff8008328000)
[ 2.517602] Call trace:
[ 2.517606] clear_bit+0x18/0x2c
[ 2.517619] kyber_finish_request+0x74/0x80
[ 2.517627] blk_mq_requeue_request+0x3c/0xc0
[ 2.517637] __scsi_queue_insert+0x11c/0x148
[ 2.517640] scsi_softirq_done+0x114/0x130
[ 2.517643] blk_done_softirq+0x7c/0xb0
[ 2.517651] __do_softirq+0x208/0x3bc
[ 2.517657] run_ksoftirqd+0x34/0x60
[ 2.517663] smpboot_thread_fn+0x1c4/0x2c0
[ 2.517667] kthread+0x110/0x120
[ 2.517669] ret_from_fork+0x10/0x18
Signed-off-by: Yang Yang <yang.yang@xxxxxxxx>
---
block/kyber-iosched.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/block/kyber-iosched.c b/block/kyber-iosched.c
index a38c5ab103d1..af73afe7a05c 100644
--- a/block/kyber-iosched.c
+++ b/block/kyber-iosched.c
@@ -611,6 +611,9 @@ static void kyber_finish_request(struct request *rq)
{
struct kyber_queue_data *kqd = rq->q->elevator->elevator_data;
+ if (unlikely(!(rq->rq_flags & RQF_ELVPRIV)))
+ return;
+
rq_clear_domain_token(kqd, rq);
}
--
2.17.1
