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

[Xiaoyao Li]

On 11/18/2023 4:35 AM, Isaku Yamahata wrote:
> On Wed, Nov 15, 2023 at 02:14:11AM -0500,
> Xiaoyao Li <xiaoyao.li@intel.com> wrote:
>
> > 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 &&
> > +        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);
> > +        if (new_block->guest_memfd < 0) {
> > +            qemu_mutex_unlock_ramlist();
> > +            return;
> > +        }
> > +    }
> > +#endif
> > +
>
> We should define kvm_create_guest_memfd() stub in accel/stub/kvm-stub.c.
> We can remove this #ifdef.

Nice suggestion! Will use stub.