Re: WARNING: CPU: 1 PID: 23668 at drivers/net/wireless/intel/iwlwifi/mvm/sta.c:1539 iwl_mvm_rm_sta+0x3ce/0x450

On 03/10/2017 08:36 AM, Luca Coelho wrote:

On Fri, 2017-03-10 at 08:23 -0700, Jens Axboe wrote:

quoted

On 03/10/2017 05:01 AM, Luca Coelho wrote:

quoted

Hi Jens,

On Thu, 2017-03-09 at 21:41 -0700, Jens Axboe wrote:

quoted

On 03/01/2017 09:10 PM, Jens Axboe wrote:

quoted

On 03/01/2017 08:33 PM, Luca Coelho wrote:

quoted

Hi Jens,

On Mar 1, 2017 20:25, Jens Axboe [off-list ref] wrote:

    Not that folks have been jumping all over this, but in case someone is
    curious, it triggered twice here today. For those two times, the value
    of mvm->pending_frames[sta_id] was 80 and 39, respectively.

Sorry for the delay, I'm on vacation now with limited internet access.
But we'll take a look into this early next week at the latest.

Thanks a lot for the detailed report!

No worries, thanks for responding. I just wanted to ensure this wasn't
dropped on the floor.

BTW, a few more values of ->pending_frames[sta_id]:

$ dmesg | grep "ret="
[ 2334.308254] ret=39
[ 7915.311828] ret=80
[31602.317204] ret=41
[32139.510993] ret=54
[33292.917759] ret=96

it seems to often happen around resume.

This is still happening all the time in current -git.

Could you collect traces with trace-cmd, as explained in our wiki[1]?
This will probably help point out the problem.  I know it's a bit
difficult because it appears to happen randomly for you, but it's worth
trying.

Sure I can, but honestly I'm a little puzzled that nobody else can
reproduce this, it happens every time I resume of switch access points.
Is anyone trying to reproduce this?

I'll have to recompile with iwlwifi tracing enabled, then I'll send a trace
when it happens.

Are you using 4.11-rc1? Or linus' master? Or...?

The trace I just sent is tip of Linus' tree. It's happened continually
since the commit I mentioned in my initial report was merged:

commit 94c3e614df2117626fccfac8f821c66e30556384
Author: Sara Sharon [off-list ref]
Date:   Wed Dec 7 15:04:37 2016 +0200

    iwlwifi: mvm: fix pending frame counter calculation

-- 
Jens Axboe