Re: [PATCH] vhost: fix vhost_dev_enable_notifiers() error case

[Michael Tokarev]

02.06.2023 19:27, Laurent Vivier wrote:
> in vhost_dev_enable_notifiers(), if virtio_bus_set_host_notifier(true)
> fails, we call vhost_dev_disable_notifiers() that executes
> virtio_bus_set_host_notifier(false) on all queues, even on queues that
> have failed to be initialized.
>
> This triggers a core dump in memory_region_del_eventfd():
>
>   virtio_bus_set_host_notifier: unable to init event notifier: Too many open 
> files (-24)
>   vhost VQ 1 notifier binding failed: 24
>   .../softmmu/memory.c:2611: memory_region_del_eventfd: Assertion `i != 
> mr->ioeventfd_nb' failed.
>
> Fix the problem by providing to vhost_dev_disable_notifiers() the
> number of queues to disable.
>
> Fixes: 8771589b6f81 ("vhost: simplify vhost_dev_enable_notifiers")
> Cc: longpeng2@huawei.com
> Signed-off-by: Laurent Vivier <lvivier@redhat.com>
> ---
>   hw/virtio/vhost.c | 65 ++++++++++++++++++++++++++---------------------
>   1 file changed, 36 insertions(+), 29 deletions(-)

Is this one a candidate for -stable?

The diffstat is somewhat large but it is just moving bit of code around.

Thanks,

/mjt