Re: [PATCH v4 02/66] RAMBlock: Add support of KVM private guest memfd

[David Hildenbrand]

>   uint8_t memory_region_get_dirty_log_mask(MemoryRegion *mr)
>   {
>       uint8_t mask = mr->dirty_log_mask;
> diff --git a/system/physmem.c b/system/physmem.c
> index c1b22bac77c2..4735b0462ed9 100644
> --- a/system/physmem.c
> +++ b/system/physmem.c
> @@ -1841,6 +1841,17 @@ static void ram_block_add(RAMBlock *new_block, Error 
> **errp)
>           }
>       }
>   
> +    if (kvm_enabled() && (new_block->flags & RAM_GUEST_MEMFD) &&
> +        new_block->guest_memfd < 0) {

How could we have a guest_memfd already at this point? Smells more like 
an assert(new_block->guest_memfd < 0);

> +        /* TODO: to decide if KVM_GUEST_MEMFD_ALLOW_HUGEPAGE is supported */

I suggest dropping that completely. As long as it's not upstream, not 
even the name of that thing is stable.

> +        new_block->guest_memfd = kvm_create_guest_memfd(new_block->max_length,
> +                                                        0, errp);
> +        if (new_block->guest_memfd < 0) {
> +            qemu_mutex_unlock_ramlist();
> +            return;
> +        }
> +    }
> +


In general, LGTM. With the two nits above:

Reviewed-by: David Hildenbrand <david@redhat.com>


--
Cheers,

David / dhildenb