Re: [PATCH v3 02/70] RAMBlock: Add support of KVM private guest memfd

[Xiaoyao Li <xiaoyao.li@xxxxxxxxx>]

On 11/20/2023 5:24 PM, David Hildenbrand wrote:
> >   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 fc2b0fee0188..0af2213cbd9c 100644
> > --- a/system/physmem.c
> > +++ b/system/physmem.c
> > @@ -1841,6 +1841,20 @@ static void ram_block_add(RAMBlock *new_block, 
> > Error **errp)
> >           }
> >       }
> > +#ifdef CONFIG_KVM
> > +    if (kvm_enabled() && new_block->flags & RAM_GUEST_MEMFD &&
>
>
> I recall that we prefer to write this as
>
>      if (kvm_enabled() && (new_block->flags & RAM_GUEST_MEMFD) &&

get it.

Thanks!

> > +        new_block->guest_memfd < 0) {
> > +        /* TODO: to decide if KVM_GUEST_MEMFD_ALLOW_HUGEPAGE is 
> > supported */
> > +        uint64_t flags = 0;
> > +        new_block->guest_memfd = 
> > kvm_create_guest_memfd(new_block->max_length,
> > +                                                        flags, errp);
>
> Get rid of "flags" and just pass 0". Whatever code wants to pass flags 
> later can decide how to do that.


How to handle it please see the reply to patch 3.