On 9/16/21 12:55 PM, Bruce Fields wrote:
On Thu, Sep 16, 2021 at 07:00:20PM +0000, Chuck Lever III wrote:
Bruce, Dai -
On Sep 16, 2021, at 2:22 PM, Dai Ngo <dai.ngo@xxxxxxxxxx> wrote:
When the back channel enters SEQ4_STATUS_CB_PATH_DOWN state, the client
recovers by sending BIND_CONN_TO_SESSION but the server fails to recover
the back channel and leaves it as NFSD4_CB_DOWN.
Fix by enhancing nfsd4_bind_conn_to_session to probe the back channel
by calling nfsd4_probe_callback.
Signed-off-by: Dai Ngo <dai.ngo@xxxxxxxxxx>
I'm wondering if this one is appropriate to pull into v5.15-rc.
I think so.
Dai, do you have a pynfs test for this case?
I don't, but I can create a pynfs test for reproduce the problem.
-Dai
--b.
---
fs/nfsd/nfs4state.c | 16 +++++++++++++---
1 file changed, 13 insertions(+), 3 deletions(-)
diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index 54e5317f00f1..63b4d0e6fc29 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -3580,7 +3580,7 @@ static struct nfsd4_conn *__nfsd4_find_conn(struct svc_xprt *xpt, struct nfsd4_s
}
static __be32 nfsd4_match_existing_connection(struct svc_rqst *rqst,
- struct nfsd4_session *session, u32 req)
+ struct nfsd4_session *session, u32 req, struct nfsd4_conn **conn)
{
struct nfs4_client *clp = session->se_client;
struct svc_xprt *xpt = rqst->rq_xprt;
@@ -3603,6 +3603,8 @@ static __be32 nfsd4_match_existing_connection(struct svc_rqst *rqst,
else
status = nfserr_inval;
spin_unlock(&clp->cl_lock);
+ if (status == nfs_ok && conn)
+ *conn = c;
return status;
}
@@ -3627,8 +3629,16 @@ __be32 nfsd4_bind_conn_to_session(struct svc_rqst *rqstp,
status = nfserr_wrong_cred;
if (!nfsd4_mach_creds_match(session->se_client, rqstp))
goto out;
- status = nfsd4_match_existing_connection(rqstp, session, bcts->dir);
- if (status == nfs_ok || status == nfserr_inval)
+ status = nfsd4_match_existing_connection(rqstp, session,
+ bcts->dir, &conn);
+ if (status == nfs_ok) {
+ if (bcts->dir == NFS4_CDFC4_FORE_OR_BOTH ||
+ bcts->dir == NFS4_CDFC4_BACK)
+ conn->cn_flags |= NFS4_CDFC4_BACK;
+ nfsd4_probe_callback(session->se_client);
+ goto out;
+ }
+ if (status == nfserr_inval)
goto out;
status = nfsd4_map_bcts_dir(&bcts->dir);
if (status)
--
2.9.5
--
Chuck Lever
