From 5b484a513149f53613d376a9d1cd0391de099fb4 Mon Sep 17 00:00:00 2001 From: Jeff Layton Date: Fri, 1 Jul 2016 09:39:20 -0400 Subject: [PATCH] ceph: clear d_fsinfo pointer under d_lock To check for a valid dentry lease, we need to get at the ceph_dentry_info. Under rcuwalk though, we may end up with a dentry that is on its way to destruction. Since we need to take the d_lock in dentry_lease_is_valid already, we can just ensure that we clear the d_fsinfo pointer out under the same lock before destroying it. Signed-off-by: Jeff Layton Reviewed-by: Yan, Zheng --- fs/ceph/dir.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/fs/ceph/dir.c b/fs/ceph/dir.c index 8ff7bcc7fc88..904dc671580f 100644 --- a/fs/ceph/dir.c +++ b/fs/ceph/dir.c @@ -1286,10 +1286,14 @@ static void ceph_d_release(struct dentry *dentry) dout("d_release %p\n", dentry); ceph_dentry_lru_del(dentry); + + spin_lock(&dentry->d_lock); + dentry->d_fsdata = NULL; + spin_unlock(&dentry->d_lock); + if (di->lease_session) ceph_put_mds_session(di->lease_session); kmem_cache_free(ceph_dentry_cachep, di); - dentry->d_fsdata = NULL; } static int ceph_snapdir_d_revalidate(struct dentry *dentry,