The patch below does not apply to the 4.9-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.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From ba851a39c9703f09684a541885ed176f8fb7c868 Mon Sep 17 00:00:00 2001
From: Yihao Wu wuyihao@linux.alibaba.com Date: Mon, 13 May 2019 14:58:22 +0800 Subject: [PATCH] NFSv4.1: Fix bug only first CB_NOTIFY_LOCK is handled
When a waiter is waked by CB_NOTIFY_LOCK, it will retry nfs4_proc_setlk(). The waiter may fail to nfs4_proc_setlk() and sleep again. However, the waiter is already removed from clp->cl_lock_waitq when handling CB_NOTIFY_LOCK in nfs4_wake_lock_waiter(). So any subsequent CB_NOTIFY_LOCK won't wake this waiter anymore. We should put the waiter back to clp->cl_lock_waitq before retrying.
Cc: stable@vger.kernel.org #4.9+ Signed-off-by: Yihao Wu wuyihao@linux.alibaba.com Reviewed-by: Jeff Layton jlayton@kernel.org Signed-off-by: Anna Schumaker Anna.Schumaker@Netapp.com
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c index 5f89bbd177c6..e38f4af20950 100644 --- a/fs/nfs/nfs4proc.c +++ b/fs/nfs/nfs4proc.c @@ -6987,20 +6987,22 @@ nfs4_retry_setlk(struct nfs4_state *state, int cmd, struct file_lock *request) init_wait(&wait); wait.private = &waiter; wait.func = nfs4_wake_lock_waiter; - add_wait_queue(q, &wait);
while(!signalled()) { + add_wait_queue(q, &wait); status = nfs4_proc_setlk(state, cmd, request); - if ((status != -EAGAIN) || IS_SETLK(cmd)) + if ((status != -EAGAIN) || IS_SETLK(cmd)) { + finish_wait(q, &wait); break; + }
status = -ERESTARTSYS; freezer_do_not_count(); wait_woken(&wait, TASK_INTERRUPTIBLE, NFS4_LOCK_MAXTIMEOUT); freezer_count(); + finish_wait(q, &wait); }
- finish_wait(q, &wait); return status; } #else /* !CONFIG_NFS_V4_1 */