This is a note to let you know that I've just added the patch titled NFSv4: Fix a nfs4_state_manager() race to the 5.15-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: nfsv4-fix-a-nfs4_state_manager-race.patch and it can be found in the queue-5.15 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 23ab5907b1fefd631ebcc5c892fb08a2b9242a64 Author: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx> Date: Sun Sep 17 19:05:50 2023 -0400 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 <trond.myklebust@xxxxxxxxxxxxxxx> Signed-off-by: Anna Schumaker <Anna.Schumaker@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/fs/nfs/nfs4state.c b/fs/nfs/nfs4state.c index 7590d059eb78e..258e6b167285c 100644 --- a/fs/nfs/nfs4state.c +++ b/fs/nfs/nfs4state.c @@ -2699,6 +2699,13 @@ 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_RECALL_RUNNING, &clp->cl_state)) { if (test_and_clear_bit(NFS4CLNT_DELEGRETURN, &clp->cl_state)) { nfs_client_return_marked_delegations(clp);