Messages in this thread | | | Date | Wed, 3 Feb 2010 21:29:13 +0100 | From | Frederic Weisbecker <> | Subject | Re: reiserfs deadlock |
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On Wed, Feb 03, 2010 at 10:08:57PM +0300, Alexander Beregalov wrote: > On 3 February 2010 22:03, Alexander Beregalov <a.beregalov@gmail.com> wrote: > > Hi Frederic > > > > I do not have previous messages and do not know how to reproduce it. > > Kernel was 2.6.33-rc5-00237-g9a3cbe3 > > > > Hm, I have the same after reboot. > > Do you need me to do anything before I try to fsck ?
Yeah. Rebooting again makes your kernel soft lockup?
Usually such softlockup happens because we have a lock inversion, in which case you should have a lockdep report before the softlockup.
Otherwise this can also happen when we wait for an event that needs the lock to complete but that can not happen because we already have the lock.
Task A hold reiserfs lock and wait for event 1 Task B wants to complete event 1 but it need the reisers lock for that => deadlock.
This can usually be found in a softlockup report: lots of tasks are blocked on reiserfs_write_lock/mutex_lock except one, and this one is important as it is probably the waiter: the task that holds the lock and that is waiting for another event (that in turn needs the lock to complete).
Having more reports could probably help us:
echo 100 > /proc/sys/kernel/hung_task_warnings
Hopefully you can still reproduce it :-s
Thanks a lot!
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