diff options
| author | Sean Christopherson <seanjc@google.com> | 2026-06-18 11:56:41 -0700 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2026-06-24 11:33:04 +0200 |
| commit | 8e5d793fc7173587cfdc075d2bb4a8d016fa050f (patch) | |
| tree | 4fbee971a946880d0a76f35285b57ed5137c3abb | |
| parent | 39e9c35e447b8ab49ddbc826c40ca31a425e76b2 (diff) | |
KVM: x86/mmu: Bug the VM, not the host kernel, if KVM write-protects upper SPTEs
Instead of bugging the host kernel, WARN and terminate the VM if KVM
attempts to write-protect at a level that cannot use leaf SPTEs.
There is no reason to bring down the entire host; even termininating
the VM is likely overkill, but in theory a missed write could corrupt
guest memory, so play it safe.
Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Kai Huang <kai.huang@intel.com>
Message-ID: <20260618185641.2022368-1-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| -rw-r--r-- | arch/x86/kvm/mmu/tdp_mmu.c | 8 |
1 files changed, 5 insertions, 3 deletions
diff --git a/arch/x86/kvm/mmu/tdp_mmu.c b/arch/x86/kvm/mmu/tdp_mmu.c index 5b3041138301..c1cbae65d239 100644 --- a/arch/x86/kvm/mmu/tdp_mmu.c +++ b/arch/x86/kvm/mmu/tdp_mmu.c @@ -1410,9 +1410,10 @@ static bool wrprot_gfn_range(struct kvm *kvm, struct kvm_mmu_page *root, u64 new_spte; bool spte_set = false; - rcu_read_lock(); + if (KVM_BUG_ON(min_level > KVM_MAX_HUGEPAGE_LEVEL, kvm)) + return false; - BUG_ON(min_level > KVM_MAX_HUGEPAGE_LEVEL); + rcu_read_lock(); for_each_tdp_pte_min_level(iter, kvm, root, min_level, start, end) { retry: @@ -1844,7 +1845,8 @@ static bool write_protect_gfn(struct kvm *kvm, struct kvm_mmu_page *root, u64 new_spte; bool spte_set = false; - BUG_ON(min_level > KVM_MAX_HUGEPAGE_LEVEL); + if (KVM_BUG_ON(min_level > KVM_MAX_HUGEPAGE_LEVEL, kvm)) + return false; rcu_read_lock(); |