These patches are based on top of: https://git.kernel.org/pub/scm/virt/kvm/kvm.git/log/?h=kvm-coco-queue and are also available from: https://github.com/AMDESE/linux/commits/kvm-gmem-common-v1/ Overview -------- This is a small collection of patches that addresses some review comments from Paolo's series: [PATCH 00/21] TDX/SNP part 1 of n, for 6.9 https://lore.kernel.org/lkml/20240227232100.478238-1-pbonzini@xxxxxxxxxx/ and also introduces some flags and interfaces that might also be relevant to the scope of that series. I'm posting these together initially as they comprise what may be the last batch of SNP dependencies that are potentially relevant to TDX and a common CoCo tree, but can split out or move back into SNP series, whatever is deemed preferable. Patch Layout ------------ 1-3: These are smaller fix-ups to address various review comments pertaining to the gmem hooks that were originally part of the SNP hypervisor postings. In each case they can be potentially squashed into the corresponding patches in kvm-coco-queue if that's preferable. 4-5: This introduces an AS_INACCESSIBLE flag that prevents unexpected accesses to hole-punched gmem pages before invalidation hooks have had a chance to make them safely accessible to the host again. 6: This implements an interface that was proposed by Sean during this[1] discussion regarding SNP_LAUNCH_UPDATE and discussed in more detail during the PUCK session "Finalizing internal guest_memfd APIs for SNP/TDX". It is not verbatim what was discussed, but is hopefully a reasonable starting point to handle use-cases like SNP_LAUNCH_UPDATE. It may also avoid the need to export kvm_gmem_get_uninit_pfn() as an external interface if SNP_LAUNCH_UPDATE is still the only known/planned user. Thanks! [1] https://lore.kernel.org/lkml/Zb1yv67h6gkYqqv9@xxxxxxxxxx/ ---------------------------------------------------------------- Michael Roth (6): KVM: guest_memfd: Fix stub for kvm_gmem_get_uninit_pfn() KVM: guest_memfd: Only call kvm_arch_gmem_prepare hook if necessary KVM: x86: Pass private/shared fault indicator to gmem_validate_fault mm: Introduce AS_INACCESSIBLE for encrypted/confidential memory KVM: guest_memfd: Use AS_INACCESSIBLE when creating guest_memfd inode KVM: guest_memfd: Add interface for populating gmem pages with user data arch/x86/include/asm/kvm_host.h | 3 ++- arch/x86/kvm/mmu/mmu.c | 3 ++- include/linux/kvm_host.h | 45 +++++++++++++++++++++++++++++++++++- include/linux/pagemap.h | 1 + mm/truncate.c | 3 ++- virt/kvm/guest_memfd.c | 51 +++++++++++++++++++++++++++++++++++++++++ 6 files changed, 102 insertions(+), 4 deletions(-)
