NFSv4: Ensure the delegation is pinned in nfs_do_return_delegation()

The call to nfs_do_return_delegation() needs to be taken without
any RCU locks. Add a refcount to make sure the delegation remains
pinned in memory until we're done.

Fixes: ee05f456772d ("NFSv4: Fix races between open and delegreturn")
Signed-off-by: Trond Myklebust <>
Signed-off-by: Anna Schumaker <>
2 files changed