Re: zfs: Fatal trap 12: page fault while in kernel mode

On Sun, Aug 02, 2009 at 11:27:14AM +0200, Juergen Unger wrote:
> Hi Pawel,
> 
> On Wed, Jul 29, 2009 at 10:47:23AM +0200, Pawel Jakub Dawidek wrote:
> > On Tue, Jul 28, 2009 at 12:50:26PM +0300, Andriy Gapon wrote:
> > > on 27/07/2009 22:58 O. Hartmann said the following:
> > > > Juergen Unger wrote:
> > > [snip]
> > > >>> _sx_xlock(3c,0,874aa28d,70f,8ae9a9f8,...) at _sx_xlock+0x43
> > > >>> dmu_buf_update_user(0,8ae9a9f8,0,0,0,...) at dmu_buf_update_user+0x35
> > > >>> zfs_znode_dmu_fini(8ae9a9f8,874b312d,1114,110b,879ab000,...) at zfs_znode_dmu_f3
> > > >>> zfs_freebsd_reclaim(fcd29c3c,1,0,8ec63754,fcd29c60,...) at zfs_freebsd_reclaim+0
> > > >>> VOP_RECLAIM_APV(874b65a0,fcd29c3c,0,0,8ec637c8,...) at VOP_RECLAIM_APV+0xa5
> > > >>> vgonel(8ec637c8,0,80c77037,386,0,...) at vgonel+0x1a4
> > > >>> vnlru_free(80f2a0f0,0,80c77037,300,3e8,...) at vnlru_free+0x2d5
> > > >>> vnlru_proc(0,fcd29d38,80c652bc,33e,871932a8,...) at vnlru_proc+0x80
> > > >>> fork_exit(8090d960,0,fcd29d38) at fork_exit+0xb8
> > > >>> fork_trampoline() at fork_trampoline+0x8
> >[snip]
> > > P.S. I see that zfs_inactive checks for z_dbuf being NULL and there is the
> > > following comment:
> > > /*
> > >  * The fs has been unmounted, or we did a
> > >  * suspend/resume and this file no longer exists.
> > >  */
> > > Maybe zfs_freebsd_reclaim should do the same?
> > 
> > Yes, you might be right.
> > 
> > Could you guys, who can reproduce it, try this patch:
> > 
> > 	http://people.freebsd.org/~pjd/patches/zfs_vnops.c.2.patch
> 
> I tried the patch, restarted the whole thing yesterday morning
> and after less then 24 hours and approximately 3215 zfs-receive
> jobs it do not crashes anymore, but the last started zfs-receive
> jobs is hanging, cannot be killed, even not with -9.  Even other
> zfs commands are hanging and cannot be killed, while zpool commands
> seems to be not affected.
> 
> root  86397  0.0  0.0  3920  1308  ??  D     3:18AM   0:00.29 zfs receive -Fv zzzz/203
> root   5001  0.0  0.0  3920  1208   0  D+   10:45AM   0:00.00 zfs list -t snapshot
> root   5477  0.0  0.0  3920  1240   3  D+   11:08AM   0:00.00 zfs list
> 
> also the sync command I tried to execute hangs forever:
> 
> root   5457  0.0  0.0  1528   492   2- D+   11:05AM   0:00.04 sync
> 
> Other parts of the system which do not have something todo with zfs
> are still working well.   I will leave the machine running in this
> state, is there something I can do to retrieve other usefull information
> for you?

If you can break into debugger and send me 'show alltrace' for starters.

-- 
Pawel Jakub Dawidek                       http://www.wheel.pl
pjd_at_FreeBSD.org                           http://www.FreeBSD.org
FreeBSD committer                         Am I Evil? Yes, I Am!