rte_vhost: do not treat empty socket message as error

Message ID 20200130080540.7616-1-vitaliy.mysak@intel.com (mailing list archive)
State Accepted, archived
Delegated to: Maxime Coquelin
Headers
Series rte_vhost: do not treat empty socket message as error |

Checks

Context Check Description
ci/checkpatch success coding style OK
ci/iol-mellanox-Performance success Performance Testing PASS
ci/iol-nxp-Performance success Performance Testing PASS
ci/iol-testing success Testing PASS
ci/Intel-compilation fail apply issues

Commit Message

Vitaliy Mysak Jan. 30, 2020, 8:05 a.m. UTC
  According to recvmsg() specification, 0 is a valid
return code when client is disconnecting.
Therefore, it should not be reported as error, unless there
are other dependencies that require message to not be empty.
But there are none, since the next immediate caller of recvmsg()
reports "vhost peer closed" info (not error) when message is empty.

This patch changes return code check for recvmsg() so that
misleading error message is not printed when the code is 0.

Signed-off-by: Vitaliy Mysak <vitaliy.mysak@intel.com>
---
 lib/librte_vhost/socket.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)
  

Comments

Tiwei Bie Feb. 5, 2020, 5:08 a.m. UTC | #1
[PATCH] rte_vhost: do not treat empty socket message as error

s/rte_vhost:/vhost:/

On Thu, Jan 30, 2020 at 09:05:39AM +0100, Vitaliy Mysak wrote:
> According to recvmsg() specification, 0 is a valid
> return code when client is disconnecting.
> Therefore, it should not be reported as error, unless there
> are other dependencies that require message to not be empty.
> But there are none, since the next immediate caller of recvmsg()
> reports "vhost peer closed" info (not error) when message is empty.
> 
> This patch changes return code check for recvmsg() so that
> misleading error message is not printed when the code is 0.

Fixes: 8f972312b8f4 ("vhost: support vhost-user")
Cc: stable@dpdk.org

> 
> Signed-off-by: Vitaliy Mysak <vitaliy.mysak@intel.com>
> ---
>  lib/librte_vhost/socket.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)

Reviewed-by: Tiwei Bie <tiwei.bie@intel.com>

Thanks,
Tiwei
  
Maxime Coquelin Feb. 5, 2020, 9:47 a.m. UTC | #2
On 1/30/20 9:05 AM, Vitaliy Mysak wrote:
> According to recvmsg() specification, 0 is a valid
> return code when client is disconnecting.
> Therefore, it should not be reported as error, unless there
> are other dependencies that require message to not be empty.
> But there are none, since the next immediate caller of recvmsg()
> reports "vhost peer closed" info (not error) when message is empty.
> 
> This patch changes return code check for recvmsg() so that
> misleading error message is not printed when the code is 0.
> 
> Signed-off-by: Vitaliy Mysak <vitaliy.mysak@intel.com>
> ---
>  lib/librte_vhost/socket.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)

Applied to dpdk-next-virtio tree.

Thanks,
Maxime
  

Patch

diff --git a/lib/librte_vhost/socket.c b/lib/librte_vhost/socket.c
index 9740fb340..0cac3ce8e 100644
--- a/lib/librte_vhost/socket.c
+++ b/lib/librte_vhost/socket.c
@@ -127,7 +127,8 @@  read_fd_message(int sockfd, char *buf, int buflen, int *fds, int max_fds,
 
 	ret = recvmsg(sockfd, &msgh, 0);
 	if (ret <= 0) {
-		VHOST_LOG_CONFIG(ERR, "recvmsg failed\n");
+		if (ret)
+			VHOST_LOG_CONFIG(ERR, "recvmsg failed\n");
 		return ret;
 	}