Patch "NFSv4.1: Fix a deadlock in layoutget" has been added to the 4.9-stable tree

This is a note to let you know that I've just added the patch titled

NFSv4.1: Fix a deadlock in layoutget

to the 4.9-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:
nfsv4.1-fix-a-deadlock-in-layoutget.patch
and it can be found in the queue-4.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Trond Myklebust <[email protected]>
Date: Mon, 23 Jan 2017 22:44:12 -0500
Subject: NFSv4.1: Fix a deadlock in layoutget

From: Trond Myklebust <[email protected]>

commit 8ac092519ad91931c96d306c4bfae2c6587c325f upstream.

We cannot call nfs4_handle_exception() without first ensuring that the slot has been freed. If not, we end up deadlocking with the process waiting for recovery to complete, and recovery waiting for the slot table to drain.

---
 fs/nfs/nfs4proc.c |    1 +
 1 file changed, 1 insertion(+)

@@ -8371,6 +8371,7 @@ nfs4_layoutget_handle_exception(struct r
 		goto out;
 	}
 
+	nfs4_sequence_free_slot(&lgp->res.seq_res);
 	err = nfs4_handle_exception(server, nfs4err, exception);
 	if (!status) {
 		if (exception->retry)

Patches currently in stable-queue which might be from [email protected] are

queue-4.9/nfsv4.0-always-send-mode-in-setattr-after-exclusive4.patch queue-4.9/sunrpc-cleanup-ida-information-when-removing-sunrpc-module.patch queue-4.9/nfsv4.1-fix-a-deadlock-in-layoutget.patch queue-4.9/nfs-don-t-increment-lock-sequence-id-after-nfs4err_moved.patch