Re: [PATCH] xen-netfront: Improve error handling during initialization

[Ross Lagerwall]

On 02/01/2017 06:54 PM, Boris Ostrovsky wrote:
> On 02/01/2017 10:50 AM, Ross Lagerwall wrote:
> > Improve error handling during initialization. This fixes a crash when
> > running out of grant refs when creating many queues across many netdevs.
> >
> > * Delay timer creation so that if initializing a queue fails, the timer
> > has not been setup yet.
> > * If creating queues fails (i.e. there are no grant refs available),
> > call xenbus_dev_fatal() to ensure that the xenbus device is set to the
> > closed state.
> > * If no queues are created, don't call xennet_disconnect_backend as
> > netdev->real_num_tx_queues will not have been set correctly.
> > * If setup_netfront() fails, ensure that all the queues created are
> > cleaned up, not just those that have been set up.
> > * If any queues were set up and an error occurs, call
> > xennet_destroy_queues() to stop the timer and clean up the napi context.
>
> We need to stop the timer in xennet_disconnect_backend(). I sent a patch
> a couple of day ago
>
> https://lists.xenproject.org/archives/html/xen-devel/2017-01/msg03269.html
>
> but was about to resend it with del_timer_sync() moved after
> napi_synchronize().

OK, but the patch is still relevant since I believe we still need to 
clean up the napi context in this case (plus the patch fixes a lot of 
other issues).

But I will respin it on top of your patch(es) and re-test it before 
resending.

--
Ross Lagerwall