[OpenAFS] Re: kernel panic in on rhel6

Derrick Brashear shadow@gmail.com
Mon, 15 Aug 2011 18:02:58 -0400

On Mon, Aug 15, 2011 at 4:26 PM, Aaron Knister <aaronk@umbc.edu> wrote:
> On Fri, Aug 12, 2011 at 12:01 PM, Andrew Deason <adeason@sinenomine.net>
> wrote:
>> On Thu, 11 Aug 2011 10:11:27 -0400
>> Aaron Knister <aaronk@umbc.edu> wrote:
>> > I know everyone's busy, but out of curiosity has anybody had a chance
>> > to look at this? Could it be that it's not even an AFS bug, but a
>> > linux kernel issue? I'm getting ready to put a webserver into
>> > production and am concerned because I can reliably trigger the
>> > mentioned kernel panic using "ab".
>> I don't think it's likely that it's a linux kernel issue. If you want
>> something to try, you can try applying these two patches:
>> http://git.openafs.org/?p=openafs.git;a=commitdiff_plain;h=910f3d4cbba4cd78a8e6afa0b32e37ed7f292d18
>> http://git.openafs.org/?p=openafs.git;a=commitdiff_plain;h=35835af9bb85b358e4bdd11113b637ac0e52c56b
>> Those fix what may be a similar issue, but I'm not really sure if it's
>> the same thing as here. If that doesn't do it (it's good that you have a
>> reliable way of reproducing this), we'll need to look more closely at
>> the core (if you don't want to provide it since it probably contains
>> file data, instructions can probably be provided, though it's a lot more
>> detailed than what we've done so far). Or we can proably go the route of
>> giving you debug patches, but I'm not quite sure what to add quite yet.
> Hi Andrew,
> Those patches do prevent it from crashing, but also results in a number of
> "permission denied" errors from the apache processes under heavy load from
> ab. The permission denied errors don't occur with 1.6.0pre7.

is there a reason 1.6.0pre7 isn't suitable, incidentally?