Re: [Qemu-devel] [PATCH v4 00/29] vhost-user reconnect fixes

[Marc-André Lureau]

Hi

On Thu, Jul 7, 2016 at 3:00 AM,  <address@hidden> wrote:
> From: Marc-André Lureau <address@hidden>
>
> Hi,
>
> Since 'vhost-user: simple reconnection support' was merged, it is
> possible to disconnect and reconnect a vhost-user backend. However,
> many code paths in qemu may trigger assert() when the backend is
> disconnected.
>
> Some assert() could simply be replaced by error_report() or silently
> fail since they are recoverable cases. Some missing error checks can
> also help prevent later issues. In many cases, the code assumes
> get_vhost_net() will be non-NULL after a succesful connection, so I
> changed it to stay after a disconnect until the new connection comes
> (as suggested by Michael). There are also code paths that are wrong,
> see "don't assume opaque is a fd" patch for an example.
>
> Since there is feature checks on reconnection, qemu should wait for
> the initial connection feature negotiation to complete. The test added
> demonstrates this. Additionally, a regression was found during v2,
> which could have been spotted with a multiqueue test, so add a basic
> one that would have exhibited the issue.
>
> For convenience, the series is also available on:
> https://github.com/elmarco/qemu, branch vhost-user-reconnect

The branch has been rebased fixing conflicts after Jason Wang "busy
polling" got merged.

I also tried to improve the commit log in "vhost: fix calling
vhost_dev_cleanup() after vhost_dev_init()" patch.

thanks

-- 
Marc-André Lureau