Merge branch 'master' into for-linus

1 files changed, 15 insertions, 0 deletions

diff --git a/fs/xfs/linux-2.6/xfs_aops.c b/fs/xfs/linux-2.6/xfs_aops.c
index 089eaca860b4..a0fa3bf0d1bb 100644
--- a/fs/xfs/linux-2.6/xfs_aops.c
+++ b/fs/xfs/linux-2.6/xfs_aops.c
@@ -1333,6 +1333,21 @@ xfs_vm_writepage(
         trace_xfs_writepage(inode, page, 0);
 
         /*
+         * Refuse to write the page out if we are called from reclaim context.
+         *
+         * This is primarily to avoid stack overflows when called from deep
+         * used stacks in random callers for direct reclaim, but disabling
+         * reclaim for kswap is a nice side-effect as kswapd causes rather
+         * suboptimal I/O patters, too.
+         *
+         * This should really be done by the core VM, but until that happens
+         * filesystems like XFS, btrfs and ext4 have to take care of this
+         * by themselves.
+         */
+        if (current->flags & PF_MEMALLOC)
+                goto out_fail;
+
+        /*
          * We need a transaction if:
          *  1. There are delalloc buffers on the page
          *  2. The page is uptodate and we have unmapped buffers