Re: [PATCH V1] net: qrtr: ns: Ignore ENODEV failures in ns

From: Simon Horman <horms@kernel.org>
To: Sarannya S <quic_sarannya@quicinc.com>
Cc: quic_bjorande@quicinc.com, andersson@kernel.org,
	quic_clew@quicinc.com, mathieu.poirier@linaro.org,
	linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org,
	linux-remoteproc@vger.kernel.org,
	Manivannan Sadhasivam <mani@kernel.org>,
	"David S. Miller" <davem@davemloft.net>,
	Eric Dumazet <edumazet@google.com>,
	Jakub Kicinski <kuba@kernel.org>, Paolo Abeni <pabeni@redhat.com>,
	"open list:NETWORKING [GENERAL]" <netdev@vger.kernel.org>
Subject: Re: [PATCH V1] net: qrtr: ns: Ignore ENODEV failures in ns
Date: Sat, 23 Dec 2023 13:56:08 +0000	[thread overview]
Message-ID: <20231223135333.GA201037@kernel.org> (raw)
In-Reply-To: <1703153211-3717-1-git-send-email-quic_sarannya@quicinc.com>

[Dropped bjorn.andersson@kernel.org, as the correct address seems
 to be andersson@kernel.org, which is already in the CC list.
 kernel.org rejected sending this email without that update.]

On Thu, Dec 21, 2023 at 03:36:50PM +0530, Sarannya S wrote:
> From: Chris Lew <quic_clew@quicinc.com>
> 
> Ignore the ENODEV failures returned by kernel_sendmsg(). These errors
> indicate that either the local port has been closed or the remote has
> gone down. Neither of these scenarios are fatal and will eventually be
> handled through packets that are later queued on the control port.
> 
> Signed-off-by: Chris Lew <quic_clew@quicinc.com>
> Signed-off-by: Sarannya Sasikumar <quic_sarannya@quicinc.com>
> ---
>  net/qrtr/ns.c | 11 +++++++----
>  1 file changed, 7 insertions(+), 4 deletions(-)
> 
> diff --git a/net/qrtr/ns.c b/net/qrtr/ns.c
> index abb0c70..8234339 100644
> --- a/net/qrtr/ns.c
> +++ b/net/qrtr/ns.c
> @@ -157,7 +157,7 @@ static int service_announce_del(struct sockaddr_qrtr *dest,
>  	msg.msg_namelen = sizeof(*dest);
>  
>  	ret = kernel_sendmsg(qrtr_ns.sock, &msg, &iv, 1, sizeof(pkt));
> -	if (ret < 0)
> +	if (ret < 0 && ret != -ENODEV)
>  		pr_err("failed to announce del service\n");
>  
>  	return ret;

Hi,

The caller of service_announce_del() ignores it's return value.
So the only action on error is the pr_err() call above, and so
with this patch -ENODEV is indeed ignored.

However, I wonder if it would make things clearer to the reader (me?)
if the return type of service_announce_del was updated void. Because
as things stand -ENODEV may be returned, which implies something might
handle that, even though it doe not.

The above notwithstanding, this change looks good to me.

Reviewed-by: Simon Horman <horms@kernel.org>

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