6.5-stable review patch. If anyone has any objections, please let me know. ------------------ From: Longfang Liu <liulongfang@xxxxxxxxxx> [ Upstream commit 33fc506d2ac514be1072499a263c3bff8c7c95a0 ] In the scenario where the accelerator business is fully loaded. When the workqueue receiving messages and performing callback processing, there are a large number of messages that need to be received, and there are continuously messages that have been processed and need to be received. This will cause the receive loop here to be locked for a long time. This scenario will cause watchdog timeout problems on OS with kernel preemption turned off. The error logs: watchdog: BUG: soft lockup - CPU#23 stuck for 23s! [kworker/u262:1:1407] [ 1461.978428][ C23] Call trace: [ 1461.981890][ C23] complete+0x8c/0xf0 [ 1461.986031][ C23] kcryptd_async_done+0x154/0x1f4 [dm_crypt] [ 1461.992154][ C23] sec_skcipher_callback+0x7c/0xf4 [hisi_sec2] [ 1461.998446][ C23] sec_req_cb+0x104/0x1f4 [hisi_sec2] [ 1462.003950][ C23] qm_poll_req_cb+0xcc/0x150 [hisi_qm] [ 1462.009531][ C23] qm_work_process+0x60/0xc0 [hisi_qm] [ 1462.015101][ C23] process_one_work+0x1c4/0x470 [ 1462.020052][ C23] worker_thread+0x150/0x3c4 [ 1462.024735][ C23] kthread+0x108/0x13c [ 1462.028889][ C23] ret_from_fork+0x10/0x18 Therefore, it is necessary to add an actively scheduled operation in the while loop to prevent this problem. After adding it, no matter whether the OS turns on or off the kernel preemption function. Neither will cause watchdog timeout issues. Signed-off-by: Longfang Liu <liulongfang@xxxxxxxxxx> Signed-off-by: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/crypto/hisilicon/qm.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/crypto/hisilicon/qm.c b/drivers/crypto/hisilicon/qm.c index ba4852744c052..2aec118ba6775 100644 --- a/drivers/crypto/hisilicon/qm.c +++ b/drivers/crypto/hisilicon/qm.c @@ -845,6 +845,8 @@ static void qm_poll_req_cb(struct hisi_qp *qp) qm_db(qm, qp->qp_id, QM_DOORBELL_CMD_CQ, qp->qp_status.cq_head, 0); atomic_dec(&qp->qp_status.used); + + cond_resched(); } /* set c_flag */ -- 2.42.0
