From: Vivek Goyal <vgoyal@redhat.com>
To: Lina Lu <lulina_nuaa@foxmail.com>
Cc: linux kernel mailing list <linux-kernel@vger.kernel.org>
Subject: Re: cfq-iosched.c: panic in cfq_dispatch_requests
Date: Mon, 21 Mar 2011 10:07:37 -0400 [thread overview]
Message-ID: <20110321140737.GA2694@redhat.com> (raw)
In-Reply-To: <201103201523220468314@foxmail.com>
On Sun, Mar 20, 2011 at 03:23:23PM +0800, Lina Lu wrote:
> Hi Vivek,
>
> I did some test with blkio weight policy these days. The kernel panic
> once in a while.
>
> >From the calltrace, It 's in func cfq_dispatch_requests(+0x058D).
> And I caught a divide by zero error with system monitor tools.
Hi Lina,
Can you please paste the full backtrace here.
>
> The panic happens when I first set 100 weight to two IO pids, then
> change the weight to 200, and begin to perform IO. The kernel panic
> accurately when the IO begin.
So you notice this only if weights are changed otherwise not?
Recently Justin fixed a bug in CFQ where crash can happen when weights
are changed. This fix in Jens's block tree. Can you please apply this
patch and see if it resolves your issue too.
commit 8184f93eced1e304721c2a55c00d87d5a14f8907
Author: Justin TerAvest <teravest@google.com>
Date: Thu Mar 17 16:12:36 2011 +0100
cfq-iosched: Don't update group weights when on service tree
Thanks
Vivek
next prev parent reply other threads:[~2011-03-21 14:08 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-03-20 7:23 cfq-iosched.c: panic in cfq_dispatch_requests Lina Lu
2011-03-21 14:07 ` Vivek Goyal [this message]
2011-03-22 15:32 ` Lina Lu
2011-03-22 15:39 ` Vivek Goyal
2011-03-22 15:48 ` Lina Lu
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=20110321140737.GA2694@redhat.com \
--to=vgoyal@redhat.com \
--cc=linux-kernel@vger.kernel.org \
--cc=lulina_nuaa@foxmail.com \
/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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).