This is a note to let you know that I've just added the patch titled
net: stmmac: fix watchdog timeout during suspend/resume stress test
to the 5.10-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:
net-stmmac-fix-watchdog-timeout-during-suspend-resume-stress-test.patch
and it can be found in the queue-5.10 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From c511819d138de38e1637eedb645c207e09680d0f Mon Sep 17 00:00:00 2001
From: Joakim Zhang <qiangqing.zhang@xxxxxxx>
Date: Thu, 25 Feb 2021 17:01:11 +0800
Subject: net: stmmac: fix watchdog timeout during suspend/resume stress test
From: Joakim Zhang <qiangqing.zhang@xxxxxxx>
commit c511819d138de38e1637eedb645c207e09680d0f upstream.
stmmac_xmit() call stmmac_tx_timer_arm() at the end to modify tx timer to
do the transmission cleanup work. Imagine such a situation, stmmac enters
suspend immediately after tx timer modified, it's expire callback
stmmac_tx_clean() would not be invoked. This could affect BQL, since
netdev_tx_sent_queue() has been called, but netdev_tx_completed_queue()
have not been involved, as a result, dql_avail(&dev_queue->dql) finally
always return a negative value.
__dev_queue_xmit->__dev_xmit_skb->qdisc_run->__qdisc_run->qdisc_restart->dequeue_skb:
if ((q->flags & TCQ_F_ONETXQUEUE) &&
netif_xmit_frozen_or_stopped(txq)) // __QUEUE_STATE_STACK_XOFF is set
Net core will stop transmitting any more. Finillay, net watchdong would timeout.
To fix this issue, we should call netdev_tx_reset_queue() in stmmac_resume().
Fixes: 54139cf3bb33 ("net: stmmac: adding multiple buffers for rx")
Signed-off-by: Joakim Zhang <qiangqing.zhang@xxxxxxx>
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 2 ++
1 file changed, 2 insertions(+)
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -5230,6 +5230,8 @@ static void stmmac_reset_queues_param(st
tx_q->cur_tx = 0;
tx_q->dirty_tx = 0;
tx_q->mss = 0;
+
+ netdev_tx_reset_queue(netdev_get_tx_queue(priv->dev, queue));
}
}
Patches currently in stable-queue which might be from qiangqing.zhang@xxxxxxx are
queue-5.10/net-stmmac-fix-wrongly-set-buffer2-valid-when-sph-unsupport.patch
queue-5.10/net-stmmac-stop-each-tx-channel-independently.patch
queue-5.10/can-flexcan-enable-rx-fifo-after-frz-halt-valid.patch
queue-5.10/net-stmmac-fix-watchdog-timeout-during-suspend-resume-stress-test.patch
queue-5.10/can-flexcan-assert-frz-bit-in-flexcan_chip_freeze.patch
queue-5.10/can-flexcan-invoke-flexcan_chip_freeze-to-enter-freeze-mode.patch
