This is a note to let you know that I've just added the patch titled
net/net_failover: fix txq exceeding warning
to the 5.4-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-net_failover-fix-txq-exceeding-warning.patch
and it can be found in the queue-5.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 15338a1ad63a46b73e214d963f8d14ad1784b194
Author: Faicker Mo <faicker.mo@xxxxxxxxx>
Date: Fri Mar 24 17:19:54 2023 +0800
net/net_failover: fix txq exceeding warning
[ Upstream commit e3cbdcb0fbb61045ef3ce0e072927cc41737f787 ]
The failover txq is inited as 16 queues.
when a packet is transmitted from the failover device firstly,
the failover device will select the queue which is returned from
the primary device if the primary device is UP and running.
If the primary device txq is bigger than the default 16,
it can lead to the following warning:
eth0 selects TX queue 18, but real number of TX queues is 16
The warning backtrace is:
[ 32.146376] CPU: 18 PID: 9134 Comm: chronyd Tainted: G E 6.2.8-1.el7.centos.x86_64 #1
[ 32.147175] Hardware name: Red Hat KVM, BIOS 1.10.2-3.el7_4.1 04/01/2014
[ 32.147730] Call Trace:
[ 32.147971] <TASK>
[ 32.148183] dump_stack_lvl+0x48/0x70
[ 32.148514] dump_stack+0x10/0x20
[ 32.148820] netdev_core_pick_tx+0xb1/0xe0
[ 32.149180] __dev_queue_xmit+0x529/0xcf0
[ 32.149533] ? __check_object_size.part.0+0x21c/0x2c0
[ 32.149967] ip_finish_output2+0x278/0x560
[ 32.150327] __ip_finish_output+0x1fe/0x2f0
[ 32.150690] ip_finish_output+0x2a/0xd0
[ 32.151032] ip_output+0x7a/0x110
[ 32.151337] ? __pfx_ip_finish_output+0x10/0x10
[ 32.151733] ip_local_out+0x5e/0x70
[ 32.152054] ip_send_skb+0x19/0x50
[ 32.152366] udp_send_skb.isra.0+0x163/0x3a0
[ 32.152736] udp_sendmsg+0xba8/0xec0
[ 32.153060] ? __folio_memcg_unlock+0x25/0x60
[ 32.153445] ? __pfx_ip_generic_getfrag+0x10/0x10
[ 32.153854] ? sock_has_perm+0x85/0xa0
[ 32.154190] inet_sendmsg+0x6d/0x80
[ 32.154508] ? inet_sendmsg+0x6d/0x80
[ 32.154838] sock_sendmsg+0x62/0x70
[ 32.155152] ____sys_sendmsg+0x134/0x290
[ 32.155499] ___sys_sendmsg+0x81/0xc0
[ 32.155828] ? _get_random_bytes.part.0+0x79/0x1a0
[ 32.156240] ? ip4_datagram_release_cb+0x5f/0x1e0
[ 32.156649] ? get_random_u16+0x69/0xf0
[ 32.156989] ? __fget_light+0xcf/0x110
[ 32.157326] __sys_sendmmsg+0xc4/0x210
[ 32.157657] ? __sys_connect+0xb7/0xe0
[ 32.157995] ? __audit_syscall_entry+0xce/0x140
[ 32.158388] ? syscall_trace_enter.isra.0+0x12c/0x1a0
[ 32.158820] __x64_sys_sendmmsg+0x24/0x30
[ 32.159171] do_syscall_64+0x38/0x90
[ 32.159493] entry_SYSCALL_64_after_hwframe+0x72/0xdc
Fix that by reducing txq number as the non-existent primary-dev does.
Fixes: cfc80d9a1163 ("net: Introduce net_failover driver")
Signed-off-by: Faicker Mo <faicker.mo@xxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/net/net_failover.c b/drivers/net/net_failover.c
index fb182bec8f062..6b7bba720d8c7 100644
--- a/drivers/net/net_failover.c
+++ b/drivers/net/net_failover.c
@@ -130,14 +130,10 @@ static u16 net_failover_select_queue(struct net_device *dev,
txq = ops->ndo_select_queue(primary_dev, skb, sb_dev);
else
txq = netdev_pick_tx(primary_dev, skb, NULL);
-
- qdisc_skb_cb(skb)->slave_dev_queue_mapping = skb->queue_mapping;
-
- return txq;
+ } else {
+ txq = skb_rx_queue_recorded(skb) ? skb_get_rx_queue(skb) : 0;
}
- txq = skb_rx_queue_recorded(skb) ? skb_get_rx_queue(skb) : 0;
-
/* Save the original txq to restore before passing to the driver */
qdisc_skb_cb(skb)->slave_dev_queue_mapping = skb->queue_mapping;
