Re: Assertion failed: RB_EMPTY_NODE(&bp->b_rbnode)

Dave Chinner
2012-04-30T23:12:27Z

On Mon, Apr 30, 2012 at 09:32:00AM -0500, Ben Myers wrote:
> While testing this patchset without Jan's freeze work, I hit this assert. I
> believe I have not seen this one before.
>
> -Ben
>
> [36850.416217] XFS: Assertion failed: RB_EMPTY_NODE(&bp->b_rbnode), file: /work/xfs/fs/xfs/xfs_buf.c, line: 838
> [36850.445669] BUG: unable to handle kernel NULL pointer dereference at 0000000000000038

Two problems - the BUG seems to be one that you have reported
before, while the assert failure tends to indicate a use after free
situation on a buffer (i.e. a log buffer has been torn down while
IO is still in progress). That smells like different symptoms of the
same problem....

I think you are going to have to debug this one, Ben, because I have
not seen anything at all like these problems on any of my test or
stress workloads. I don't even know what test you are running at the
time these failures are occurring, so I can't even start looking...

Cheers,

Dave.
--
Dave Chinner
david@fromorbit.com