[PATCH 0/4] KVM: x86/mmu: Fix TDP MMU dirty logging bug L2 running with EPT disabled

[David Matlack <dmatlack@google.com>]

Fix a bug in the TDP MMU caught by syzkaller and CONFIG_KVM_PROVE_MMU
that causes writes made by L2 to no be reflected in the dirty log when
L1 has disabled EPT.

Patch 1 contains the fix. Patch 2 and 3 fix comments related to clearing
dirty bits in the TDP MMU. Patch 4 adds selftests coverage of dirty
logging of L2 when L1 has disabled EPT. i.e.  a regression test for this
bug.

David Matlack (4):
  KVM: x86/mmu: Check kvm_mmu_page_ad_need_write_protect() when clearing
    TDP MMU dirty bits
  KVM: x86/mmu: Remove function comments above
    clear_dirty_{gfn_range,pt_masked}()
  KVM: x86/mmu: Fix and clarify comments about clearing D-bit vs.
    write-protecting
  KVM: selftests: Add coverage of EPT-disabled to vmx_dirty_log_test

 arch/x86/kvm/mmu/tdp_mmu.c                    | 51 +++++++---------
 .../selftests/kvm/x86_64/vmx_dirty_log_test.c | 60 ++++++++++++++-----
 2 files changed, 68 insertions(+), 43 deletions(-)


base-commit: 687d8f4c3dea0758afd748968d91288220bbe7e3
-- 
2.44.0.291.gc1ea87d7ee-goog