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From:   trondmy@kernel.org
To:     Anna Schumaker <anna.schumaker@netapp.com>
Cc:     linux-nfs@vger.kernel.org
Subject: [PATCH 5/5] NFSv4: Don't hold the layoutget locks across multiple RPC calls
Date:   Sat, 14 May 2022 10:08:14 -0400
Message-Id: <20220514140814.3655-5-trondmy@kernel.org>
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From: Trond Myklebust <trond.myklebust@hammerspace.com>

When doing layoutget as part of the open() compound, we have to be
careful to release the layout locks before we can call any further RPC
calls, such as setattr(). The reason is that those calls could trigger
a recall, which could deadlock.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
---
 fs/nfs/nfs4proc.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index a79f66432bd3..bf3ba541b9fb 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -3098,6 +3098,10 @@ static int _nfs4_open_and_get_state(struct nfs4_opendata *opendata,
 	}
 
 out:
+	if (opendata->lgp) {
+		nfs4_lgopen_release(opendata->lgp);
+		opendata->lgp = NULL;
+	}
 	if (!opendata->cancelled)
 		nfs4_sequence_free_slot(&opendata->o_res.seq_res);
 	return ret;
-- 
2.36.1