From: Ben Greear <greearb@candelatech.com>
To: Avery Pennarun <apenwarr@gmail.com>
Cc: ath10k <ath10k@lists.infradead.org>
Subject: Re: Firmware crash when sending large numbers of forwarded packets
Date: Fri, 07 Mar 2014 17:08:43 -0800 [thread overview]
Message-ID: <531A6D9B.4060605@candelatech.com> (raw)
In-Reply-To: <CAHqTa-2Be3Whehq4tG1vSxBikLGuTeFMQmbYT5K3D1ui4hRumw@mail.gmail.com>
On 03/07/2014 04:54 PM, Avery Pennarun wrote:
> On Fri, Mar 7, 2014 at 10:53 AM, Ben Greear <greearb@candelatech.com> wrote:
>> That is interesting, sending from LAN will often burst higher
>> and cause more packet loss (and perhaps higher periodic packet
>> loads) but sending locally will typically allow the local stack to back
>> off more gracefully.
>
> That theory sounds right. Do you think there's a way to simulate the
> burstiness while avoiding the extra machine? That would make testing
> easier. Some way to write a lot of packets to a socket and then
> release it all at once? I'm guessing UDP would work better for this
> than TCP.
UDP has some local backpressure as well, but maybe it would be more
likely to hit it than TCP I guess.
It could also be something else related to forwarding that is not just
rate specific (maybe frames come in with LRO and something special
about transmitting those, or something of that nature?).
Are you using bridging or routing on your AP? Bridging might
be fundamentally different than routing as far as this bug
is concerned. Sending from local AP would likely emulate
routing type behaviour.
>> This appears to be an assert in firmware, not just random crash.
>>
>> Someone with .467 firmware source and a bit of skill with the tool-chain
>> should be able to figure out where it is asserting.
>>
>> I do not know anyone with both of those things, however :P
>
> Maybe I should try harder to get access to the firmware source :)
Good luck..if you do get it and the toolchain, I can point
you towards how to decode (ie, get stack trace) that crash, or at least I can send
QCA email they could forward you (to satisfy any NDA isues).
Thanks,
Ben
--
Ben Greear <greearb@candelatech.com>
Candela Technologies Inc http://www.candelatech.com
_______________________________________________
ath10k mailing list
ath10k@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/ath10k
next prev parent reply other threads:[~2014-03-08 1:09 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-03-07 10:38 Firmware crash when sending large numbers of forwarded packets Avery Pennarun
2014-03-07 11:15 ` Michal Kazior
2014-03-07 15:53 ` Ben Greear
2014-03-08 0:54 ` Avery Pennarun
2014-03-08 1:08 ` Ben Greear [this message]
2014-03-08 1:21 ` Avery Pennarun
2014-03-10 7:47 ` Michal Kazior
2014-03-08 8:03 ` Kalle Valo
2014-03-08 8:20 ` Avery Pennarun
2014-03-08 16:57 ` Kalle Valo
2014-03-10 19:26 ` Avery Pennarun
2014-03-11 7:31 ` Kalle Valo
2014-03-10 10:10 ` Michal Kazior
2014-03-10 10:16 ` Michal Kazior
2014-05-12 1:43 ` Avery Pennarun
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=531A6D9B.4060605@candelatech.com \
--to=greearb@candelatech.com \
--cc=apenwarr@gmail.com \
--cc=ath10k@lists.infradead.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.