Re: 4.19 - tons of hw csum failure errors

(Cc'ing Eric)

On Sat, Oct 27, 2018 at 12:47 PM Nikola Ciprich
[off-list ref] wrote:

Hi,

just wanted to report, thet after switching to 4.19 (fro 4.14.x, so maybe
the problem appeared somewhere between), I'm getting tons of similar
messages:

Oct 27 09:06:27 xxx kernel: br501: hw csum failure
Oct 27 09:06:27 xxx kernel: CPU: 8 PID: 0 Comm: swapper/8 Tainted: G            E     4.19.0lb7.00_01_PRE04 #1
Oct 27 09:06:27 xxx kernel: Hardware name: Supermicro Super Server/X11DDW-NT, BIOS 2.0b 03/07/2018
Oct 27 09:06:27 xxx kernel: Call Trace:
Oct 27 09:06:27 xxx kernel:  <IRQ>
Oct 27 09:06:27 xxx kernel:  dump_stack+0x5a/0x73
Oct 27 09:06:27 xxx kernel:  __skb_checksum_complete+0xba/0xc0
Oct 27 09:06:27 xxx kernel:  tcp_error+0x108/0x180 [nf_conntrack]
Oct 27 09:06:27 xxx kernel:  nf_conntrack_in+0xd2/0x4b0 [nf_conntrack]
Oct 27 09:06:27 xxx kernel:  ? csum_partial+0xd/0x20
Oct 27 09:06:27 xxx kernel:  nf_hook_slow+0x3d/0xb0
Oct 27 09:06:27 xxx kernel:  ip_rcv+0xb5/0xd0
Oct 27 09:06:27 xxx kernel:  ? ip_rcv_finish_core.isra.12+0x370/0x370
Oct 27 09:06:27 xxx kernel:  __netif_receive_skb_one_core+0x52/0x70
Oct 27 09:06:27 xxx kernel:  process_backlog+0xa3/0x150
Oct 27 09:06:27 xxx kernel:  net_rx_action+0x2af/0x3f0
Oct 27 09:06:27 xxx kernel:  __do_softirq+0xd1/0x28c
Oct 27 09:06:27 xxx kernel:  irq_exit+0xde/0xf0
Oct 27 09:06:27 xxx kernel:  do_IRQ+0x54/0xe0
Oct 27 09:06:27 xxx kernel:  common_interrupt+0xf/0xf
Oct 27 09:06:27 xxx kernel:  </IRQ>

We got the same warning (but a different backtrace) with mlx5 driver.

It seems you are using a different driver. Do you have any clue to reproduce
it?

If you do, try to tcpdump the packets triggering this warning, it could
be useful for debugging.

As I explained in other thread, it is likely that commit 88078d98d1bb
introduces more troubles than the one fixed by d55bef5059dd057bd.
You can try to play with these two commits to see if you get the same
conclusion.

BTW, the offending commit has been backported to 4.14 too. ;)

Thanks!