Re: [PATCH] net/virtio-net: reverse unregistering on exit

["Michael S. Tsirkin" <mst@redhat.com>]

On Tue, Aug 22, 2017 at 04:59:51PM +0200, Pierre Morel wrote:
> Hi,
> 
> I got a problem with virtio-net in a QEMU guest.
> 
> When virtio-net is used as a module in a guest and the network is
> activated, removing the virtio-net modules produces a kernel error:
> 
> [ 2375.624949] Last Breaking-Event-Address:
> [ 2375.624954]  [<00000000001453d4>] __cpuhp_remove_state+0x84/0x1a8
> [ 2375.624959] ---[ end trace cc9fd68b89f5235a ]---
> [ 2375.624966] Error: Removing state 163 which has instances left.
> [ 2375.624985] ------------[ cut here ]------------

Which kernel do you use?


> The problem is produced by an inversion in the order of unregistering
> the driver and the hotplug state machine callbacks in virtio_net_driver_exit.
> 
> This patch solves the problem by first unregistering the virtio_net_driver
> before unregistering the hotplug state machine callbacks.
> 
> Best regards,
> 
> Pierre Morel
> 
> Pierre Morel (1):
>   net/virtio-net: reverse unregistering on exit
> 
>  drivers/net/virtio_net.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> -- 
> 2.7.4