Re: [Qemu-devel] [PATCH] vhost: fix a migration failed because of vhost region merge

[Igor Mammedov <imammedo@redhat.com>]

On Wed, 19 Jul 2017 23:17:32 +0800
Peng Hao <peng.hao2@zte.com.cn> wrote:

> When a guest that has several hotplugged dimms is migrated, in
> destination host it will fail to resume. Because vhost regions of
> several dimms in source host are merged and in the restore stage
> in destination host it computes whether more than vhost slot limit
> before merging vhost regions of several dimms.
could you provide a bit more detailed description of the problem
including command line+used device_add commands on source and
command line on destination?

> 
> Signed-off-by: Peng Hao <peng.hao2@zte.com.cn>
> Signed-off-by: Wang Yechao <wang.yechao255@zte.com.cn>
> ---
>  hw/mem/pc-dimm.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/hw/mem/pc-dimm.c b/hw/mem/pc-dimm.c
> index ea67b46..bb0fa08 100644
> --- a/hw/mem/pc-dimm.c
> +++ b/hw/mem/pc-dimm.c
> @@ -101,7 +101,7 @@ void pc_dimm_memory_plug(DeviceState *dev, MemoryHotplugState *hpms,
>          goto out;
>      }
>  
> -    if (!vhost_has_free_slot()) {
> +    if (!vhost_has_free_slot() && runstate_is_running()) {
>          error_setg(&local_err, "a used vhost backend has no free"
>                                 " memory slots left");
>          goto out;