Re: XFS assertion from truncate. (3.10-rc2)

[Dave Chinner <david@fromorbit.com>]

On Tue, May 21, 2013 at 07:40:16PM -0400, Dave Jones wrote:
> On Wed, May 22, 2013 at 09:34:29AM +1000, Dave Chinner wrote:
>  > On Tue, May 21, 2013 at 06:52:57PM -0400, Dave Jones wrote:
>  > > [  464.210598] XFS: Assertion failed: (mask & (ATTR_MODE|ATTR_UID|ATTR_GID|ATTR_ATIME|ATTR_ATIME_SET| ATTR_MTIME_SET|ATTR_KILL_SUID|ATTR_KILL_SGID| ATTR_KILL_PRIV|ATTR_TIMES_SET)) == 0, file: fs/xfs/xfs_iops.c, line: 719
>  > 
>  > Never seen that fire before, but this is why we have ASSERT()s like
>  > this - we're being handed something by the VFS we don't expect...
>  > 
>  > Can you give me some context of the file permissions before the
>  > syscall and what the syscall parameters are? i.e. is this likely to
>  > be trying to strip SUID/SGID during the truncate operation?
> 
> no idea tbh. Is there something I can add to that assert to dump
> which file it was triggered by ?

Convert the assert to a if (), and then in the body do something
like:

	if (mask & (...) {
		char buf[MAX_PATHLEN];

		d_path(VFS_I(ip)->i_dentry, buf, MAXPATHLEN);
		xfs_warn(mp, "%s: mask 0x%x mismatch on file %s\n",
			 __func__, mask, buf);
		ASSERT(0);
	}

Cheers,

Dave.
-- 
Dave Chinner
david@fromorbit.com