Re: xfs: possible deadlock warning

From: Dave Chinner
Date: Wed May 28 2014 - 02:01:21 EST


On Wed, May 28, 2014 at 01:19:16PM +0800, Gu Zheng wrote:
> Hi all,
> When running the latest Linus' tree, the following possible deadlock warning occurs.

false positive. There isn't a deadlock between inode locks on
different filesystems. i.e. there is no dependency between shmem
inodes and xfs inodes, nor on their security contexts. Nor can you
take a page fault on a directory inode, which is the XFS inode lock
class it's complaining about.

Fundamentally, the problem here is shmem instantiating a new inode
with the mmap_sem held. That's just plain wrong...


Cheers,

Dave.
--
Dave Chinner
david@xxxxxxxxxxxxx
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/