From d5681f59ee3d4a2e60b9234e94c163cbbf559d0a Mon Sep 17 00:00:00 2001 From: Anna Schumaker Date: Thu, 14 Jun 2018 09:39:17 -0400 Subject: NFS: Fix an rcu deadlock in nfs_delegation_find_inode() I was able to reproduce this pretty regularily using xfstests generic/013 on NFS v4.0. Reported-by: Ross Zwisler Fixes: 6c342655022d (NFSv4: Return NFS4ERR_DELAY when a delegation recall fails due to igrab()) Signed-off-by: Anna Schumaker Signed-off-by: Trond Myklebust --- fs/nfs/delegation.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'fs/nfs') diff --git a/fs/nfs/delegation.c b/fs/nfs/delegation.c index bbd0465535eb..f033f3a69a3b 100644 --- a/fs/nfs/delegation.c +++ b/fs/nfs/delegation.c @@ -883,8 +883,10 @@ struct inode *nfs_delegation_find_inode(struct nfs_client *clp, rcu_read_lock(); list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) { res = nfs_delegation_find_inode_server(server, fhandle); - if (res != ERR_PTR(-ENOENT)) + if (res != ERR_PTR(-ENOENT)) { + rcu_read_unlock(); return res; + } } rcu_read_unlock(); return ERR_PTR(-ENOENT); -- cgit v1.2.3-59-g8ed1b