From 4db72b40fdbc706f8957e9773ae73b1574b8c694 Mon Sep 17 00:00:00 2001 From: Jeff Layton Date: Tue, 28 Jan 2014 13:47:46 -0500 Subject: nfs: add memory barriers around NFS_INO_INVALID_DATA and NFS_INO_INVALIDATING If the setting of NFS_INO_INVALIDATING gets reordered to before the clearing of NFS_INO_INVALID_DATA, then another task may hit a race window where both appear to be clear, even though the inode's pages are still in need of invalidation. Fix this by adding the appropriate memory barriers. Signed-off-by: Jeff Layton Signed-off-by: Trond Myklebust --- fs/nfs/inode.c | 1 + 1 file changed, 1 insertion(+) (limited to 'fs/nfs/inode.c') diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c index e5070aa5f175..02e185168602 100644 --- a/fs/nfs/inode.c +++ b/fs/nfs/inode.c @@ -1050,6 +1050,7 @@ int nfs_revalidate_mapping(struct inode *inode, struct address_space *mapping) } set_bit(NFS_INO_INVALIDATING, bitlock); + smp_wmb(); nfsi->cache_validity &= ~NFS_INO_INVALID_DATA; spin_unlock(&inode->i_lock); trace_nfs_invalidate_mapping_enter(inode); -- cgit v1.2.3