Re: [RFC PATCH 0/5] KVM: guest_memfd: support for uffd missing

[Peter Xu]

On Fri, Mar 14, 2025 at 05:12:35PM +0000, Nikita Kalyazin wrote:
> Yes, I was thinking about MADV_POPULATE_WRITE as well, but AFAIK it isn't
> available in guest_memfd, at least with direct map removed due to [1] being
> updated in [2]:

I see, so GUP is no-go.  IIUC the userapp can also prefault by writing
zeros in a loop after mmap().

Thanks,

-- 
Peter Xu