Re: possible ext4 race situation freezing linux

[Andreas Friedrich Berendsen <afberendsen@gmail.com>]

Tso & Eric,

I'll try again to reproduce the error, but when the system freezes, I
have the X interface running. And, indeed, I'm not familiar with the
behaviour of sysreq. Which sysrq should I use when the problem happens?
Will the system change to the text interface? If there are no disk
activity (all leds are off), where the information will be recorded?

-- Berendsen

-----Original Message-----
From: Eric Sandeen <sandeen@redhat.com>
To: Theodore Tso <tytso@mit.edu>
Cc: Andreas Friedrich Berendsen <afberendsen@gmail.com>,
linux-ext4@vger.kernel.org
Subject: Re: possible ext4 race situation freezing linux
Date: Tue, 24 Feb 2009 09:38:17 -0600

Theodore Tso wrote:
> On Wed, Feb 25, 2009 at 01:22:22AM +1300, Andreas Friedrich Berendsen wrote:
>> Kernel version: 2.26.28.7
>> efs2progs version: 1.41.4
>> arch: x86_64 (amd)
>>
>> I made this test four times and the results  were the same: linux
>> freezes and becomes unresponsive. Only solution is to reset the box. I
>> do not know if the problem is with the USB devices sub-subsystem or a
>> possible ext4 race condition.
> 
> Can you use alt-sysrq to get some stack traces or a register dump out,
> so we can see where the kernel is hanging?
> 
>       	      	    	       	  - Ted

alt-sysrq-w would be a good place to start (just in case you're not
familiar w/ the sysrq keys)

It'd also be great to test w/ 2.6.29, as a deadlock was fixed there
recently (it's on its way to .28.x too AFAIK)

Thanks,

-Eric
-- 
__________________________________________
Andreas Friedrich Berendsen
SCA OCP MSCA A+ Linux+ Network+ HpMASE