CC Omar
On 9/7/20 1:43 AM, Yang Yang wrote:
> 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);
> }
>
>
--
Jens Axboe
