This is a note to let you know that I've just added the patch titled
net: hns3: fix deadlock issue when externel_lb and reset are executed together
to the 6.4-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-hns3-fix-deadlock-issue-when-externel_lb-and-reset-are-executed-together.patch
and it can be found in the queue-6.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From ac6257a3ae5db5193b1f19c268e4f72d274ddb88 Mon Sep 17 00:00:00 2001
From: Yonglong Liu <liuyonglong@xxxxxxxxxx>
Date: Mon, 7 Aug 2023 19:34:52 +0800
Subject: net: hns3: fix deadlock issue when externel_lb and reset are executed together
From: Yonglong Liu <liuyonglong@xxxxxxxxxx>
commit ac6257a3ae5db5193b1f19c268e4f72d274ddb88 upstream.
When externel_lb and reset are executed together, a deadlock may
occur:
[ 3147.217009] INFO: task kworker/u321:0:7 blocked for more than 120 seconds.
[ 3147.230483] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[ 3147.238999] task:kworker/u321:0 state:D stack: 0 pid: 7 ppid: 2 flags:0x00000008
[ 3147.248045] Workqueue: hclge hclge_service_task [hclge]
[ 3147.253957] Call trace:
[ 3147.257093] __switch_to+0x7c/0xbc
[ 3147.261183] __schedule+0x338/0x6f0
[ 3147.265357] schedule+0x50/0xe0
[ 3147.269185] schedule_preempt_disabled+0x18/0x24
[ 3147.274488] __mutex_lock.constprop.0+0x1d4/0x5dc
[ 3147.279880] __mutex_lock_slowpath+0x1c/0x30
[ 3147.284839] mutex_lock+0x50/0x60
[ 3147.288841] rtnl_lock+0x20/0x2c
[ 3147.292759] hclge_reset_prepare+0x68/0x90 [hclge]
[ 3147.298239] hclge_reset_subtask+0x88/0xe0 [hclge]
[ 3147.303718] hclge_reset_service_task+0x84/0x120 [hclge]
[ 3147.309718] hclge_service_task+0x2c/0x70 [hclge]
[ 3147.315109] process_one_work+0x1d0/0x490
[ 3147.319805] worker_thread+0x158/0x3d0
[ 3147.324240] kthread+0x108/0x13c
[ 3147.328154] ret_from_fork+0x10/0x18
In externel_lb process, the hns3 driver call napi_disable()
first, then the reset happen, then the restore process of the
externel_lb will fail, and will not call napi_enable(). When
doing externel_lb again, napi_disable() will be double call,
cause a deadlock of rtnl_lock().
This patch use the HNS3_NIC_STATE_DOWN state to protect the
calling of napi_disable() and napi_enable() in externel_lb
process, just as the usage in ndo_stop() and ndo_start().
Fixes: 04b6ba143521 ("net: hns3: add support for external loopback test")
Signed-off-by: Yonglong Liu <liuyonglong@xxxxxxxxxx>
Signed-off-by: Jijie Shao <shaojijie@xxxxxxxxxx>
Reviewed-by: Leon Romanovsky <leonro@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20230807113452.474224-5-shaojijie@xxxxxxxxxx
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/net/ethernet/hisilicon/hns3/hns3_enet.c | 14 +++++++++++++-
1 file changed, 13 insertions(+), 1 deletion(-)
--- a/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c
+++ b/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c
@@ -5854,6 +5854,9 @@ void hns3_external_lb_prepare(struct net
if (!if_running)
return;
+ if (test_and_set_bit(HNS3_NIC_STATE_DOWN, &priv->state))
+ return;
+
netif_carrier_off(ndev);
netif_tx_disable(ndev);
@@ -5882,7 +5885,16 @@ void hns3_external_lb_restore(struct net
if (!if_running)
return;
- hns3_nic_reset_all_ring(priv->ae_handle);
+ if (hns3_nic_resetting(ndev))
+ return;
+
+ if (!test_bit(HNS3_NIC_STATE_DOWN, &priv->state))
+ return;
+
+ if (hns3_nic_reset_all_ring(priv->ae_handle))
+ return;
+
+ clear_bit(HNS3_NIC_STATE_DOWN, &priv->state);
for (i = 0; i < priv->vector_num; i++)
hns3_vector_enable(&priv->tqp_vector[i]);
Patches currently in stable-queue which might be from liuyonglong@xxxxxxxxxx are
queue-6.4/net-hns3-fix-deadlock-issue-when-externel_lb-and-reset-are-executed-together.patch
