Commit 3ba31603 authored May 07, 2012 by Peter Watkins Committed by Ben Myers May 21, 2012

xfs: fix memory reclaim deadlock on agi buffer



Note xfs_iget can be called while holding a locked agi buffer. If
it goes into memory reclaim then inode teardown may try to lock the
same buffer. Prevent the deadlock by calling radix_tree_preload
with GFP_NOFS.

Signed-off-by: Peter Watkins <treestem@gmail.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Ben Myers <bpm@sgi.com>

parent ea562ed6

fs/xfs/xfs_iget.c

+3 −2

Original line number	Diff line number	Diff line
		@@ -317,9 +317,10 @@ xfs_iget_cache_miss(
		/*
		* Preload the radix tree so we can insert safely under the
		* write spinlock. Note that we cannot sleep inside the preload
		* region.
		* region. Since we can be called from transaction context, don't
		* recurse into the file system.
		*/
		if (radix_tree_preload(GFP_KERNEL)) {
		if (radix_tree_preload(GFP_NOFS)) {
		error = EAGAIN;
		goto out_destroy;
		}