Subject: RE: [PATCH v4.4.y, v4.9.y] igb: Remove incorrect "unexpected SYS WRAP" log message

From: "Keller, Jacob E" <[email-masked]>
Date: Wed, 10 Feb 2021 01:46:46 +0000

> -----Original Message-----
> From: Punit Agrawal <[email-masked]>
> Sent: Tuesday, February 09, 2021 5:35 PM
> To: [email-masked]
> Cc: Brandeburg, Jesse <[email-masked]>; Nguyen, Anthony L
> <[email-masked]>; [email-masked];
> [email-masked]; Corinna Vinschen <[email-masked]>;
> Keller, Jacob E <[email-masked]>; Brown, Aaron F
> <[email-masked]>; Jeff Kirsher <[email-masked]>
> Subject: [PATCH v4.4.y, v4.9.y] igb: Remove incorrect "unexpected SYS WRAP" log
> message
> 
> From: Corinna Vinschen <[email-masked]>
> 
> commit 2643e6e90210e16c978919617170089b7c2164f7 upstream
> 
> TSAUXC.DisableSystime is never set, so SYSTIM runs into a SYS WRAP
> every 1100 secs on 80580/i350/i354 (40 bit SYSTIM) and every 35000
> secs on 80576 (45 bit SYSTIM).
> 
> This wrap event sets the TSICR.SysWrap bit unconditionally.
> 
> However, checking TSIM at interrupt time shows that this event does not
> actually cause the interrupt.  Rather, it's just bycatch while the
> actual interrupt is caused by, for instance, TSICR.TXTS.
> 
> The conclusion is that the SYS WRAP is actually expected, so the
> "unexpected SYS WRAP" message is entirely bogus and just helps to
> confuse users.  Drop it.
> 
> Signed-off-by: Corinna Vinschen <[email-masked]>
> Acked-by: Jacob Keller <[email-masked]>
> Tested-by: Aaron Brown <[email-masked]>
> Signed-off-by: Jeff Kirsher <[email-masked]>
> ---
> Hi,
> 
> A customer reported that the following message appears in the kernel
> logs every 1100s -
> 
>     igb 0000:01:00.1: unexpected SYS WRAP
> 
> As the systems have large uptimes the messages are crowding the logs.
> 
> The message was dropped in
> commit 2643e6e90210e16c ("igb: Remove incorrect "unexpected SYS WRAP" log
> message")
> in v4.14.
> 
> Please consider applying to patch to v4.4 and v4.9 stable kernels - it
> applies cleanly to both the trees.
> 
> Thanks,
> Punit
> 

It makes sense to me for htis to apply to those stable trees as well.

Thanks,
Jake