From 5e1c1bf53e5f3213d5c74466cefd7cd9bbffbb37 Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Sun, 17 Sep 2023 19:05:50 -0400 Subject: [PATCH] NFSv4: Fix a nfs4_state_manager() race [ Upstream commit ed1cc05aa1f7fe8197d300e914afc28ab9818f89 ] If the NFS4CLNT_RUN_MANAGER flag got set just before we cleared NFS4CLNT_MANAGER_RUNNING, then we might have won the race against nfs4_schedule_state_manager(), and are responsible for handling the recovery situation. Fixes: aeabb3c96186 ("NFSv4: Fix a NFSv4 state manager deadlock") Signed-off-by: Trond Myklebust Signed-off-by: Anna Schumaker Signed-off-by: Sasha Levin --- fs/nfs/nfs4state.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/fs/nfs/nfs4state.c b/fs/nfs/nfs4state.c index 04aa8e34d112..1aacb0aa07f0 100644 --- a/fs/nfs/nfs4state.c +++ b/fs/nfs/nfs4state.c @@ -2623,6 +2623,13 @@ static void nfs4_state_manager(struct nfs_client *clp) nfs4_end_drain_session(clp); nfs4_clear_state_manager_bit(clp); + if (test_bit(NFS4CLNT_RUN_MANAGER, &clp->cl_state) && + !test_and_set_bit(NFS4CLNT_MANAGER_RUNNING, + &clp->cl_state)) { + memflags = memalloc_nofs_save(); + continue; + } + if (!test_and_set_bit(NFS4CLNT_DELEGRETURN_RUNNING, &clp->cl_state)) { if (test_and_clear_bit(NFS4CLNT_DELEGRETURN, &clp->cl_state)) { nfs_client_return_marked_delegations(clp);