From: Johannes Hirte <johannes.hirte@fem.tu-ilmenau.de>
To: Chris Mason <chris.mason@oracle.com>
Subject: Re: task imap:2958 blocked for more than 120 seconds
Date: Wed, 13 Jan 2010 23:37:33 +0100
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Am Sonntag 10 Januar 2010 21:19:26 schrieb Chris Mason:
> On Sun, Jan 10, 2010 at 09:05:46PM +0100, Johannes Hirte wrote:
> > I've observed this hanging task now several times. Not sure when this
> > started, but 2.6.32 is affected too, IIRC. I don't have a test pattern
> > for this. Dovecot imap triggers this from time to time. I've enabled
> > CONFIG_DETECT_HUNG_TASK now
> 
> > and got this two tasks which hang:
> You're stuck on a read, could you please do a sysrq-w when this happens?

Will do so when it happens again.

> Also, do you eventually recover or are you stuck forever?

I didn't wait too long when it happened, so I'm not sure.  The longest time 
I've waited was 20-30min, until reboot without recover. So either it's stuck 
forever or it takes really long to recover.

And one question I have: How do you identify a read in this call trace? 

regards,
  Johannes
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