[GIT PULL] KVM: GUEST_MEMFD fixes for 6.8

[Sean Christopherson <seanjc@google.com>]

Minor fixes related GUEST_MEMFD.  I _just_ posted these, and they've only
been in -next for one night, but I am sending this now to ensure you see it
asap, as patch 1 in particular affects KVM's ABI, i.e. really should land
in 6.8 before GUEST_MEMFD support is officially released.

The following changes since commit c48617fbbe831d4c80fe84056033f17b70a31136:

  Merge tag 'kvmarm-fixes-6.8-3' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD (2024-02-21 05:18:56 -0500)

are available in the Git repository at:

  https://github.com/kvm-x86/linux.git tags/kvm-x86-guest_memfd_fixes-6.8

for you to fetch changes up to 2dfd2383034421101300a3b7325cf339a182d218:

  KVM: selftests: Add a testcase to verify GUEST_MEMFD and READONLY are exclusive (2024-02-22 17:07:06 -0800)

----------------------------------------------------------------
KVM GUEST_MEMFD fixes for 6.8:

 - Make KVM_MEM_GUEST_MEMFD mutually exclusive with KVM_MEM_READONLY to
   avoid creating ABI that KVM can't sanely support.

 - Update documentation for KVM_SW_PROTECTED_VM to make it abundantly
   clear that such VMs are purely a development and testing vehicle, and
   come with zero guarantees.

 - Limit KVM_SW_PROTECTED_VM guests to the TDP MMU, as the long term plan
   is to support confidential VMs with deterministic private memory (SNP
   and TDX) only in the TDP MMU.

 - Fix a bug in a GUEST_MEMFD negative test that resulted in false passes
   when verifying that KVM_MEM_GUEST_MEMFD memslots can't be dirty logged.

----------------------------------------------------------------
Sean Christopherson (5):
      KVM: Make KVM_MEM_GUEST_MEMFD mutually exclusive with KVM_MEM_READONLY
      KVM: x86: Update KVM_SW_PROTECTED_VM docs to make it clear they're a WIP
      KVM: x86/mmu: Restrict KVM_SW_PROTECTED_VM to the TDP MMU
      KVM: selftests: Create GUEST_MEMFD for relevant invalid flags testcases
      KVM: selftests: Add a testcase to verify GUEST_MEMFD and READONLY are exclusive

 Documentation/virt/kvm/api.rst                       |  5 +++++
 arch/x86/kvm/Kconfig                                 |  7 ++++---
 arch/x86/kvm/x86.c                                   |  2 +-
 tools/testing/selftests/kvm/set_memory_region_test.c | 12 +++++++++++-
 virt/kvm/kvm_main.c                                  |  8 +++++++-
 5 files changed, 28 insertions(+), 6 deletions(-)