diff mbox

[RFC,8/8] btrfs: use __GFP_NOFAIL in alloc_btrfs_bio

Message ID 1438768284-30927-9-git-send-email-mhocko@kernel.org (mailing list archive)
State New, archived
Headers show

Commit Message

Michal Hocko Aug. 5, 2015, 9:51 a.m. UTC 
From: Michal Hocko <mhocko@suse.com>

alloc_btrfs_bio is relying on GFP_NOFS to allocate a bio but since "mm:
page_alloc: do not lock up GFP_NOFS allocations upon OOM" this is
allowed to fail which can lead to
[   37.928625] kernel BUG at fs/btrfs/extent_io.c:4045

This is clearly undesirable and the nofail behavior should be explicit
if the allocation failure cannot be tolerated.

Signed-off-by: Michal Hocko <mhocko@suse.com>
---
 fs/btrfs/volumes.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

David Sterba Aug. 5, 2015, 4:32 p.m. UTC | #1 
On Wed, Aug 05, 2015 at 11:51:24AM +0200, mhocko@kernel.org wrote:
> From: Michal Hocko <mhocko@suse.com>
> 
> alloc_btrfs_bio is relying on GFP_NOFS to allocate a bio but since "mm:
> page_alloc: do not lock up GFP_NOFS allocations upon OOM" this is
> allowed to fail which can lead to
> [   37.928625] kernel BUG at fs/btrfs/extent_io.c:4045
> 
> This is clearly undesirable and the nofail behavior should be explicit
> if the allocation failure cannot be tolerated.
> 
> Signed-off-by: Michal Hocko <mhocko@suse.com>

Reviewed-by: David Sterba <dsterba@suse.com>
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diff mbox

Patch

diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 53af23f2c087..57a99d19533d 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -4914,7 +4914,7 @@  static struct btrfs_bio *alloc_btrfs_bio(int total_stripes, int real_stripes)
 		 * and the stripes
 		 */
 		sizeof(u64) * (total_stripes),
-		GFP_NOFS);
+		GFP_NOFS|__GFP_NOFAIL);
 	if (!bbio)
 		return NULL;