5.4-stable review patch. If anyone has any objections, please let me know.
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From: Chuck Lever chuck.lever@oracle.com
commit 961b4b5e86bf56a2e4b567f81682defa5cba957e upstream.
I noticed that once an NFSv4.1 callback operation gets a NFS4ERR_DELAY status on CB_SEQUENCE and then the connection is lost, the callback client loops, resending it indefinitely.
The switch arm in nfsd4_cb_sequence_done() that handles NFS4ERR_DELAY uses rpc_restart_call() to rearm the RPC state machine for the retransmit, but that path does not call the rpc_prepare_call callback again. Thus cb_seq_status is set to -10008 by the first NFS4ERR_DELAY result, but is never set back to 1 for the retransmits.
nfsd4_cb_sequence_done() thinks it's getting nothing but a long series of CB_SEQUENCE NFS4ERR_DELAY replies.
Fixes: 7ba6cad6c88f ("nfsd: New helper nfsd4_cb_sequence_done() for processing more cb errors") Reviewed-by: Jeff Layton jlayton@kernel.org Reviewed-by: Benjamin Coddington bcodding@redhat.com Signed-off-by: Chuck Lever chuck.lever@oracle.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- fs/nfsd/nfs4callback.c | 1 + 1 file changed, 1 insertion(+)
--- a/fs/nfsd/nfs4callback.c +++ b/fs/nfsd/nfs4callback.c @@ -1060,6 +1060,7 @@ static bool nfsd4_cb_sequence_done(struc ret = false; break; case -NFS4ERR_DELAY: + cb->cb_seq_status = 1; if (!rpc_restart_call(task)) goto out;