This is a note to let you know that I've just added the patch titled
crypto: hisilicon/qm - prevent soft lockup in receive loop
to the 6.6-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
crypto-hisilicon-qm-prevent-soft-lockup-in-receive-l.patch
and it can be found in the queue-6.6 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit b8179e662de4dbd259e5fc8b94eac15183c459e2
Author: Longfang Liu <liulongfang@xxxxxxxxxx>
Date: Fri Oct 20 17:35:58 2023 +0800
crypto: hisilicon/qm - prevent soft lockup in receive loop
[ 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>
diff --git a/drivers/crypto/hisilicon/qm.c b/drivers/crypto/hisilicon/qm.c
index 1638c0a7df310..193b0b3a77cda 100644
--- a/drivers/crypto/hisilicon/qm.c
+++ b/drivers/crypto/hisilicon/qm.c
@@ -847,6 +847,8 @@ 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 */
