Re: [Qemu-devel] vhost-user: fix crash when chardev-remove

[Marc-André Lureau]

Hi

On Wed, Jan 11, 2017 at 3:32 PM 黄淮 <address@hidden> wrote:

> From: Huai Huang<address@hidden>
>
>
>
Could you describe a bit more the crash and provide a backtrace?


> diff --git a/hw/net/vhost_net.c b/hw/net/vhost_net.c
> index f2d49ad..4037cf4 100644
> --- a/hw/net/vhost_net.c
> +++ b/hw/net/vhost_net.c
> @@ -412,7 +412,6 @@ VHostNetState *get_vhost_net(NetClientState *nc)
>          break;
>      case NET_CLIENT_DRIVER_VHOST_USER:
>          vhost_net = vhost_user_get_vhost_net(nc);
> -        assert(vhost_net);
>

This was recently added, in commit
1a5b68cee8a2b165ffd61b2e0641a4da3990f242.

How is it related?

I remember the rest of the vhost-user code expected get_vhost_net() to be
non-null, did that change?

         break;
>      default:
>          break;
> diff --git a/net/vhost-user.c b/net/vhost-user.c
> index b0595f8..4e54478 100644
> --- a/net/vhost-user.c
> +++ b/net/vhost-user.c
> @@ -160,7 +160,10 @@ static void vhost_user_cleanup(NetClientState *nc)
>          qemu_chr_fe_release(s->chr);
>          s->chr = NULL;
>      }
> -
> +    if (s->watch) {
> +        g_source_remove(s->watch);
> +        s->watch = 0;
> +    }
>

Hmm, the socket didn't send a CLOSED event on remove?


>      qemu_purge_queued_packets(nc);
>  }
>
>
> @@ -192,7 +195,8 @@ static gboolean net_vhost_user_watch(GIOChannel *chan,
> GIOCondition cond,
>  {
>      VhostUserState *s = opaque;
>
>
> -    qemu_chr_disconnect(s->chr);
> +    if (s->chr)
> +        qemu_chr_disconnect(s->chr);
>

that looks outdated,

which version of qemu did you tested and patched?

thanks

>
>
>      return FALSE;
>  }

-- 
Marc-André Lureau