Re: [PATCH v3 26/28] KVM: selftests: Split out helper to allocate guest mem via memfd

[Paolo Bonzini]

On 3/1/22 00:36, David Woodhouse wrote:
> On Sat, 2022-02-26 at 00:15 +0000, Sean Christopherson wrote:
> > Extract the code for allocating guest memory via memfd out of
> > vm_userspace_mem_region_add() and into a new helper, kvm_memfd_alloc().
> > A future selftest to populate a guest with the maximum amount of guest
> > memory will abuse KVM's memslots to alias guest memory regions to a
> > single memfd-backed host region, i.e. needs to back a guest with memfd
> > memory without a 1:1 association between a memslot and a memfd instance.
> >
> > No functional change intended.
> >
> > Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>
>
> While we're at it, please can we make the whole thing go away and just
> return failure #ifndef MFD_CLOEXEC, instead of breaking the build on
> older userspace?

We can just use old school F_SETFD if that's helpful for you.

Paolo