Re: bio linked list corruption.

[Josef Bacik]

On 10/21/2016 04:38 PM, Chris Mason wrote:
> On 10/21/2016 04:23 PM, Dave Jones wrote:
> > On Fri, Oct 21, 2016 at 04:17:48PM -0400, Chris Mason wrote:
> >
> >  > > BTRFS warning (device sda3): csum failed ino 130654 off 0 csum 2566472073
> > expected csum 3008371513
> >  > > BTRFS warning (device sda3): csum failed ino 131057 off 4096 csum
> > 3563910319 expected csum 738595262
> >  > > BTRFS warning (device sda3): csum failed ino 131176 off 4096 csum
> > 1344477721 expected csum 441864825
> >  > > BTRFS warning (device sda3): csum failed ino 131241 off 245760 csum
> > 3576232181 expected csum 2566472073
> >  > > BTRFS warning (device sda3): csum failed ino 131429 off 0 csum 1494450239
> > expected csum 2646577722
> >  > > BTRFS warning (device sda3): csum failed ino 131471 off 0 csum 3949539320
> > expected csum 3828807800
> >  > > BTRFS warning (device sda3): csum failed ino 131471 off 4096 csum
> > 3475108475 expected csum 2566472073
> >  > > BTRFS warning (device sda3): csum failed ino 131471 off 958464 csum
> > 142982740 expected csum 2566472073
> >  > > BTRFS warning (device sda3): csum failed ino 131471 off 0 csum 3949539320
> > expected csum 3828807800
> >  > > BTRFS warning (device sda3): csum failed ino 131532 off 270336 csum
> > 3138898528 expected csum 2566472073
> >  > > BTRFS warning (device sda3): csum failed ino 131532 off 1249280 csum
> > 2169165042 expected csum 2566472073
> >  > > BTRFS warning (device sda3): csum failed ino 131649 off 16384 csum
> > 2914965650 expected csum 1425742005
> >  > >
> >  > >
> >  > > A curious thing: the expected csum 2566472073 turns up a number of times
> > for different inodes, and gets
> >  > > differing actual csums each time.  I suppose this could be something like
> > a block of all zeros in multiple files,
> >  > > but it struck me as surprising.
> >  > >
> >  > > btrfs people: is there an easy way to map those inodes to a filename ?
> > I'm betting those are the
> >  > > test files that trinity generates. If so, it might point to a race
> > somewhere.
> >  >
> >  > btrfs inspect inode 130654 mntpoint
> >
> > Interesting, they all return
> >
> > ERROR: ino paths ioctl: No such file or directory
> >
> > So these files got deleted perhaps ?
> Yeah, they must have.

So one thing that will cause spurious csum errors is if you do things like 
change the memory while it is in flight during O_DIRECT.  Does trinity do that? 
If so then that would explain it.  If not we should probably dig into it.  Thanks,

Josef