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Date:   Thu, 12 Oct 2023 20:23:29 -0400
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Subject: Re: [PATCH v1] svcrdma: Drop connection after an RDMA Read error
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To:     Chuck Lever <cel@kernel.org>, linux-nfs@vger.kernel.org
Cc:     stable@vger.kernel.org, Chuck Lever <chuck.lever@oracle.com>
References: <169695862158.5083.6004887085023503434.stgit@oracle-102.nfsv4bat.org>
From:   Tom Talpey <tom@talpey.com>
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On 10/10/2023 1:23 PM, Chuck Lever wrote:
> From: Chuck Lever <chuck.lever@oracle.com>
> 
> When an RPC Call message cannot be pulled from the client, that
> is a message loss, by definition. Close the connection to trigger
> the client to resend.

This looks correct, but it seems there are actually two changes here,
it's initiating the close but it's also unconditionally returning
-ENOTCONN. Other similar code paths do this so it's ok but the
altered return value is a bit mysterious.

Reviewed-by: Tom Talpey <tom@talpey.com>

> 
> Cc: <stable@vger.kernel.org>
> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
> ---
>   net/sunrpc/xprtrdma/svc_rdma_recvfrom.c |    3 ++-
>   1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c b/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c
> index 85c8bcaebb80..3b05f90a3e50 100644
> --- a/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c
> +++ b/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c
> @@ -852,7 +852,8 @@ int svc_rdma_recvfrom(struct svc_rqst *rqstp)
>   	if (ret == -EINVAL)
>   		svc_rdma_send_error(rdma_xprt, ctxt, ret);
>   	svc_rdma_recv_ctxt_put(rdma_xprt, ctxt);
> -	return ret;
> +	svc_xprt_deferred_close(xprt);
> +	return -ENOTCONN;
>   
>   out_backchannel:
>   	svc_rdma_handle_bc_reply(rqstp, ctxt);
> 
> 
>