Re: [PATCH v2 16/16] virtio-mem: Mark memslot alias memory regions unmergeable

Philippe Mathieu-Daudé
2023-08-28T22:45:25Z

On 25/8/23 15:21, David Hildenbrand wrote:
> Let's mark the memslot alias memory regions as unmergable, such that
> flatview and vhost won't merge adjacent memory region aliases and we can
> atomically map/unmap individual aliases without affecting adjacent
> alias memory regions.
>
> This handles vhost and vfio in multiple-memslot mode correctly (which do
> not support atomic memslot updates) and avoids the temporary removal of
> large memslots, which can be an expensive operation. For example, vfio
> might have to unpin + repin a lot of memory, which is undesired.
>
> Signed-off-by: David Hildenbrand <david@redhat.com>
> ---
> hw/virtio/virtio-mem.c | 6 ++++++
> 1 file changed, 6 insertions(+)

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>