Re: BTRFS hang with 3.16-rc5 (and also with 3.16-rc4)

[Martin Steigerwald <Martin@lichtvoll.de>]

Am Donnerstag, 24. Juli 2014, 10:58:51 schrieb Chris Mason:
> On 07/23/2014 06:47 PM, Martin Steigerwald wrote:
> > Am Dienstag, 15. Juli 2014, 17:08:27 schrieb Martin Steigerwald:
> >> Am Dienstag, 15. Juli 2014, 09:21:40 schrieb Chris Mason:
> >>> On 07/14/2014 05:58 PM, Martin Steigerwald wrote:
> >>>> Am Montag, 14. Juli 2014, 16:12:22 schrieb Chris Mason:
> >>>>> On 07/14/2014 11:10 AM, Martin Steigerwald wrote:
> >>>>>> Am Montag, 14. Juli 2014, 17:04:22 schrieben Sie:
> >>>>>>> Hi!
> >>>>>>> 
> >>>>>>> While with 3.16-rc3 and rc4 I didn´t have a BTRFS hang in several
> >>>>>>> days
> >>>>>>> of
> >>>>>>> usage, with 3-16-rc5 I had a hang again. Less than a hour since
> >>>>>>> booting
> >>>>>>> it.
> >>>>>>> 
> >>>>>>> Since the hang bug I and others had with 3.15 and upto 3.16-rc2
> >>>>>>> usually
> >>>>>>> didn´t happen that quickly after boot and since backtrace looks a
> >>>>>>> bit
> >>>>>>> different from what I have in memory, I post this in a new thread.
> >>>>>>> See thread "Blocked tasks on 3.15.1" for a discussion of previous
> >>>>>>> hang
> >>>>>>> issues.
> >>>>>> 
> >>>>>> Probably good to add some basic information on the filesystem:
> >>>>> Do you have compression enabled?  I wasn't able to nail down the
> >>>>> 3.15.1
> >>>>> hang before vacation attacked me, but I'm hoping to track it down
> >>>>> today.
> >>>> 
> >>>> Yes. I have.
> >>>> 
> >>>> It just hung again while I was playing PlaneShift.
> >>>> 
> >>>> Back to 3.16-rc4 as rc5 seems to be broke here.
> >>> 
> >>> The btrfs hang you're hitting goes back to 3.15.  So 3.16-rc4 vs rc5
> >>> shouldn't be a factor.  Are you hitting other problems with 3.16?
> >> 
> >> So far for this day 3.16-rc4 behaves nicely. With 3.16-rc5 I had a BTRFS
> >> hang twice yesterday. 3.16-rc4 before also behaved nicely for several
> >> days
> >> or well about a week here.
> > 
> > 3.16-rc4 now hung as well…
> 
> Liu Bo has a promising patch:
> 
> https://patchwork.kernel.org/patch/4618421/
> 
> Please give it a shot.  There's a second deadlock reading the free space
> cache, I'm still working on that one too.

Okay, I reverted your printk patch and applied this on on git linus git.

Lets see how this works.

-- 
Martin 'Helios' Steigerwald - http://www.Lichtvoll.de
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