The patch below does not apply to the 4.19-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-4.19.y git checkout FETCH_HEAD git cherry-pick -x 1cbc11aaa01f80577b67ae02c73ee781112125fd # <resolve conflicts, build, test, etc.> git commit -s git send-email --to 'stable@vger.kernel.org' --in-reply-to '2023082613-lilac-overpower-64a2@gregkh' --subject-prefix 'PATCH 4.19.y' HEAD^..

Possible dependencies:

1cbc11aaa01f ("NFSv4: Fix dropped lock for racing OPEN and delegation return")

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 1cbc11aaa01f80577b67ae02c73ee781112125fd Mon Sep 17 00:00:00 2001 From: Benjamin Coddington bcodding@redhat.com Date: Fri, 30 Jun 2023 09:18:13 -0400 Subject: [PATCH] NFSv4: Fix dropped lock for racing OPEN and delegation return

Commmit f5ea16137a3f ("NFSv4: Retry LOCK on OLD_STATEID during delegation return") attempted to solve this problem by using nfs4's generic async error handling, but introduced a regression where v4.0 lock recovery would hang. The additional complexity introduced by overloading that error handling is not necessary for this case. This patch expects that commit to be reverted.

The problem as originally explained in the above commit is:

There's a small window where a LOCK sent during a delegation return can race with another OPEN on client, but the open stateid has not yet been updated. In this case, the client doesn't handle the OLD_STATEID error from the server and will lose this lock, emitting: "NFS: nfs4_handle_delegation_recall_error: unhandled error -10024".

Fix this by using the old_stateid refresh helpers if the server replies with OLD_STATEID.

Suggested-by: Trond Myklebust trondmy@hammerspace.com Signed-off-by: Benjamin Coddington bcodding@redhat.com Signed-off-by: Trond Myklebust trond.myklebust@hammerspace.com

diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c index e1a886b58354..4604e9f3d1b0 100644 --- a/fs/nfs/nfs4proc.c +++ b/fs/nfs/nfs4proc.c @@ -7181,8 +7181,15 @@ static void nfs4_lock_done(struct rpc_task *task, void *calldata) } else if (!nfs4_update_lock_stateid(lsp, &data->res.stateid)) goto out_restart; break; - case -NFS4ERR_BAD_STATEID: case -NFS4ERR_OLD_STATEID: + if (data->arg.new_lock_owner != 0 && + nfs4_refresh_open_old_stateid(&data->arg.open_stateid, + lsp->ls_state)) + goto out_restart; + if (nfs4_refresh_lock_old_stateid(&data->arg.lock_stateid, lsp)) + goto out_restart; + fallthrough; + case -NFS4ERR_BAD_STATEID: case -NFS4ERR_STALE_STATEID: case -NFS4ERR_EXPIRED: if (data->arg.new_lock_owner != 0) {