On Thu, Aug 28, 2025, Rick P Edgecombe wrote: > On Wed, 2025-08-27 at 16:33 +0800, Yan Zhao wrote: > > On Tue, Aug 26, 2025 at 05:05:15PM -0700, Sean Christopherson wrote: > > > Don't explicitly pin pages when mapping pages into the S-EPT, guest_memfd > > > doesn't support page migration in any capacity, i.e. there are no migrate > > > callbacks because guest_memfd pages *can't* be migrated. See the WARN in > > > kvm_gmem_migrate_folio(). > > Hmm, we implemented exactly the same patch at [1], where we explained the > > potential problems of not holding page refcount, and the explored various > > approaches, and related considerations. > > > > [1] https://lore.kernel.org/all/20250807094241.4523-1-yan.y.zhao@xxxxxxxxx/ Oh, nice! I'll grab that and massage the changelog to break the hard dependencies on the rest of the hugepage support. > Yea, so the outcome of the huge page related discussion was that we should look > at some sort of emergency page reclaim feature for the TDX module to use in the > case of bugs. But in the meantime to move forward without it, using a solution > like in this patch.
