diff options
| author | David Matlack <dmatlack@google.com> | 2022-01-25 23:05:15 +0000 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2022-02-10 13:50:32 -0500 |
| commit | 115111efd97c6c0e86f8b5904c6624fddcfe4f34 (patch) | |
| tree | e56472f8d5376879f8961fabb462c482e4015747 /arch/x86/kvm/mmu/mmu.c | |
| parent | 932859a4e0b9fa12ba315e88e3d29f9d2f638916 (diff) | |
KVM: x86/mmu: Check SPTE writable invariants when setting leaf SPTEs
Check SPTE writable invariants when setting SPTEs rather than in
spte_can_locklessly_be_made_writable(). By the time KVM checks
spte_can_locklessly_be_made_writable(), the SPTE has long been since
corrupted.
Note that these invariants only apply to shadow-present leaf SPTEs (i.e.
not to MMIO SPTEs, non-leaf SPTEs, etc.). Add a comment explaining the
restriction and only instrument the code paths that set shadow-present
leaf SPTEs.
To account for access tracking, also check the SPTE writable invariants
when marking an SPTE as an access track SPTE. This also lets us remove
a redundant WARN from mark_spte_for_access_track().
Suggested-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: David Matlack <dmatlack@google.com>
Message-Id: <20220125230518.1697048-3-dmatlack@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'arch/x86/kvm/mmu/mmu.c')
| -rw-r--r-- | arch/x86/kvm/mmu/mmu.c | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c index 9f1b4711d5ea..0f9e0e95f365 100644 --- a/arch/x86/kvm/mmu/mmu.c +++ b/arch/x86/kvm/mmu/mmu.c @@ -529,6 +529,7 @@ static u64 mmu_spte_update_no_track(u64 *sptep, u64 new_spte) u64 old_spte = *sptep; WARN_ON(!is_shadow_present_pte(new_spte)); + check_spte_writable_invariants(new_spte); if (!is_shadow_present_pte(old_spte)) { mmu_spte_set(sptep, new_spte); |