From 20dafeefac97d1a690b113f2a954dc84fdf8f290 Mon Sep 17 00:00:00 2001 From: Byoungyoung Lee Date: Wed, 25 Mar 2015 14:57:53 +1100 Subject: [PATCH] xfs: xfs_mru_cache_insert() should use GFP_NOFS xfs_mru_cache_insert() can be called from within transaction context during block allocation like so: write(2) .... xfs_get_blocks xfs_iomap_write_direct start transaction xfs_bmapi_write xfs_bmapi_allocate xfs_bmap_btalloc xfs_bmap_btalloc_filestreams xfs_filestream_new_ag xfs_filestream_pick_ag xfs_mru_cache_insert radix_tree_preload(GFP_KERNEL) In this case, GFP_KERNEL is incorrect and can potentially lead to deadlocks in memory reclaim. It should use GFP_NOFS allocations to avoid lock recursion problems. [dchinner: rewrote commit message] Signed-off-by: Byoungyoung Lee Signed-off-by: Sanidhya Kashyap Reviewed-by: Dave Chinner Signed-off-by: Dave Chinner --- fs/xfs/xfs_mru_cache.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/xfs/xfs_mru_cache.c b/fs/xfs/xfs_mru_cache.c index 30ecca3037e3..f8a674d7f092 100644 --- a/fs/xfs/xfs_mru_cache.c +++ b/fs/xfs/xfs_mru_cache.c @@ -437,7 +437,7 @@ xfs_mru_cache_insert( if (!mru || !mru->lists) return -EINVAL; - if (radix_tree_preload(GFP_KERNEL)) + if (radix_tree_preload(GFP_NOFS)) return -ENOMEM; INIT_LIST_HEAD(&elem->list_node); -- 2.39.5