From: Christoph Hellwig <hch@infradead.org>
Date: Sat, 18 Jul 2009 22:14:54 +0000 (-0400)
Subject: xfs: switch to NOFS allocation under i_lock in xfs_getbmap
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=ca35dcd6cae7d4a780c484c53f45548c4719f82c;p=GitHub%2FLineageOS%2FG12%2Fandroid_kernel_amlogic_linux-4.9.git

xfs: switch to NOFS allocation under i_lock in xfs_getbmap

xfs_getbmap allocates memory with i_lock held, but i_lock is taken in
reclaim context so all allocations under it must avoid recursions into
the filesystem.

Reported by the new reclaim context tracing in lockdep.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Felix Blyakher <felixb@sgi.com>
Signed-off-by: Felix Blyakher <felixb@sgi.com>
---

diff --git a/fs/xfs/xfs_bmap.c b/fs/xfs/xfs_bmap.c
index 7928b9983c1d..8ee5b5a76a2a 100644
--- a/fs/xfs/xfs_bmap.c
+++ b/fs/xfs/xfs_bmap.c
@@ -6009,7 +6009,7 @@ xfs_getbmap(
 	 */
 	error = ENOMEM;
 	subnex = 16;
-	map = kmem_alloc(subnex * sizeof(*map), KM_MAYFAIL);
+	map = kmem_alloc(subnex * sizeof(*map), KM_MAYFAIL | KM_NOFS);
 	if (!map)
 		goto out_unlock_ilock;