Re: [PATCH 19/52] migration/rdma: Fix qemu_get_cm_event_timeout() to always set error

[Zhijian Li (Fujitsu)]

On 18/09/2023 22:41, Markus Armbruster wrote:
> qemu_get_cm_event_timeout() neglects to set an error when it fails
> because rdma_get_cm_event() fails.  Harmless, as its caller
> qemu_rdma_connect() substitutes a generic error then.  Fix it anyway.
> 
> qemu_rdma_connect() also sets the generic error when its own call of
> rdma_get_cm_event() fails.  Make the error handling more obvious: set
> a specific error right after rdma_get_cm_event() fails.  Delete the
> generic error.
> 
> Signed-off-by: Markus Armbruster <armbru@redhat.com>


Reviewed-by: Li Zhijian <lizhijian@fujitsu.com>



> ---
>   migration/rdma.c | 10 ++++++++--
>   1 file changed, 8 insertions(+), 2 deletions(-)
> 
> diff --git a/migration/rdma.c b/migration/rdma.c
> index 08cd186385..d3dc162363 100644
> --- a/migration/rdma.c
> +++ b/migration/rdma.c
> @@ -2509,7 +2509,11 @@ static int qemu_get_cm_event_timeout(RDMAContext *rdma,
>           ERROR(errp, "failed to poll cm event, errno=%i", errno);
>           return -1;
>       } else if (poll_fd.revents & POLLIN) {
> -        return rdma_get_cm_event(rdma->channel, cm_event);
> +        if (rdma_get_cm_event(rdma->channel, cm_event) < 0) {
> +            ERROR(errp, "failed to get cm event");
> +            return -1;
> +        }
> +        return 0;
>       } else {
>           ERROR(errp, "no POLLIN event, revent=%x", poll_fd.revents);
>           return -1;
> @@ -2559,10 +2563,12 @@ static int qemu_rdma_connect(RDMAContext *rdma, bool 
> return_path,
>           ret = qemu_get_cm_event_timeout(rdma, &cm_event, 5000, errp);
>       } else {
>           ret = rdma_get_cm_event(rdma->channel, &cm_event);
> +        if (ret < 0) {
> +            ERROR(errp, "failed to get cm event");
> +        }
>       }
>       if (ret) {
>           perror("rdma_get_cm_event after rdma_connect");
> -        ERROR(errp, "connecting to destination!");
>           goto err_rdma_source_connect;
>       }
>