Re: [PATCH RFC 4/5] KVM: add new members to the memory slot for double buffering of bitmaps

Avi Kivity
2010-04-12T09:19:47Z

On 04/12/2010 05:15 AM, Takuya Yoshikawa wrote:
>
> OK, but we have one problem: ia64. I checked all architectures' dirty
> bitmap
> implementations and thought generalizing this work is not so hard
> except for
> ia64. It's already too different from other parts.
>
> #ifdef CONFIG_IA64
> unsigned long *dirty_bitmap;
> #else
> ...
> #endif
>
> is acceptable?

I think you can keep the bitmap in userspace, but replace the vmalloc()
with get_user_pages() and vmap() (in arch/ia64). 'dirty_bitmap' can
then be in kvm->arch.

Note: this will likely break ia64 without testing. Please copy the
patches to kvm-ia64@vger.kernel.org so they can test and fix them if
they want to.

The patches should at least build, though. If you don't have an ia64
machine, I can build-test them for you.

--
I have a truly marvellous patch that fixes the bug which this
signature is too narrow to contain.