diff options
| author | David Matlack <dmatlack@google.com> | 2023-10-27 20:26:39 +0300 |
|---|---|---|
| committer | Sean Christopherson <seanjc@google.com> | 2023-12-01 18:52:07 +0300 |
| commit | 45a61ebb221117748d3567a86908618f431ac824 (patch) | |
| tree | cf869ad355c985b7ecbd2e881c9ca3c29715bf58 /arch/x86/kvm/mmu | |
| parent | 1aa4bb916808503bf6fedd00f50f2077f91cebaa (diff) | |
| download | linux-45a61ebb221117748d3567a86908618f431ac824.tar.xz | |
KVM: x86/mmu: Check for leaf SPTE when clearing dirty bit in the TDP MMU
Re-check that the given SPTE is still a leaf and present SPTE after a
failed cmpxchg in clear_dirty_gfn_range(). clear_dirty_gfn_range()
intends to only operate on present leaf SPTEs, but that could change
after a failed cmpxchg.
A check for present was added in commit 3354ef5a592d ("KVM: x86/mmu:
Check for present SPTE when clearing dirty bit in TDP MMU") but the
check for leaf is still buried in tdp_root_for_each_leaf_pte() and does
not get rechecked on retry.
Fixes: a6a0b05da9f3 ("kvm: x86/mmu: Support dirty logging for the TDP MMU")
Signed-off-by: David Matlack <dmatlack@google.com>
Link: https://lore.kernel.org/r/20231027172640.2335197-3-dmatlack@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Diffstat (limited to 'arch/x86/kvm/mmu')
| -rw-r--r-- | arch/x86/kvm/mmu/tdp_mmu.c | 7 |
1 files changed, 4 insertions, 3 deletions
diff --git a/arch/x86/kvm/mmu/tdp_mmu.c b/arch/x86/kvm/mmu/tdp_mmu.c index 6cd4dd631a2f..038983b13574 100644 --- a/arch/x86/kvm/mmu/tdp_mmu.c +++ b/arch/x86/kvm/mmu/tdp_mmu.c @@ -1522,12 +1522,13 @@ static bool clear_dirty_gfn_range(struct kvm *kvm, struct kvm_mmu_page *root, rcu_read_lock(); - tdp_root_for_each_leaf_pte(iter, root, start, end) { + tdp_root_for_each_pte(iter, root, start, end) { retry: - if (tdp_mmu_iter_cond_resched(kvm, &iter, false, true)) + if (!is_shadow_present_pte(iter.old_spte) || + !is_last_spte(iter.old_spte, iter.level)) continue; - if (!is_shadow_present_pte(iter.old_spte)) + if (tdp_mmu_iter_cond_resched(kvm, &iter, false, true)) continue; KVM_MMU_WARN_ON(kvm_ad_enabled() && |