Re: [RFC] Badness in __mutex_unlock_slowpath with XFS stress tests

[Nathan Scott <nathans@xxxxxxx>]

On Thu, Mar 09, 2006 at 10:42:19PM +0000, Christoph Hellwig wrote:
> On Fri, Mar 10, 2006 at 09:30:42AM +1100, Nathan Scott wrote:
> > Not for reads AFAICT - __generic_file_aio_read + own-locking
> > should always have released i_mutex at the end of the direct
> > read - are you thinking of writes or have I missed something?
> 
> if an error occurs before a_ops->direct_IO is called __generic_file_aio_read
> will return with i_mutex still locked.  Note that checking for negative
> return values is not enough as __blockdev_direct_IO can return errors
> aswell.

*groan* - right you are.  Another option may be to have the
generic dio+own-locking case reacquire i_mutex if it drops
it, before returning... thoughts?  Seems alot less invasive
than the filemap.c code dup'ing thing.

cheers.

-- 
Nathan