From 427c76aed29ec12a57f11546a5036df3cc52855e Mon Sep 17 00:00:00 2001 From: Sean Christopherson Date: Fri, 28 Jul 2023 18:35:32 -0700 Subject: [PATCH] KVM: x86/mmu: Bug the VM if write-tracking is used but not enabled Bug the VM if something attempts to write-track a gfn, but write-tracking isn't enabled. The VM is doomed (and KVM has an egregious bug) if KVM or KVMGT wants to shadow guest page tables but can't because write-tracking isn't enabled. Tested-by: Yongwei Ma Link: https://lore.kernel.org/r/20230729013535.1070024-27-seanjc@google.com Signed-off-by: Sean Christopherson Signed-off-by: Paolo Bonzini --- arch/x86/kvm/mmu/page_track.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/x86/kvm/mmu/page_track.c b/arch/x86/kvm/mmu/page_track.c index 2c6b912..9bf0131 100644 --- a/arch/x86/kvm/mmu/page_track.c +++ b/arch/x86/kvm/mmu/page_track.c @@ -90,7 +90,7 @@ void kvm_write_track_add_gfn(struct kvm *kvm, struct kvm_memory_slot *slot, lockdep_assert_once(lockdep_is_held(&kvm->slots_lock) || srcu_read_lock_held(&kvm->srcu)); - if (WARN_ON_ONCE(!kvm_page_track_write_tracking_enabled(kvm))) + if (KVM_BUG_ON(!kvm_page_track_write_tracking_enabled(kvm), kvm)) return; update_gfn_write_track(slot, gfn, 1); @@ -122,7 +122,7 @@ void kvm_write_track_remove_gfn(struct kvm *kvm, lockdep_assert_once(lockdep_is_held(&kvm->slots_lock) || srcu_read_lock_held(&kvm->srcu)); - if (WARN_ON_ONCE(!kvm_page_track_write_tracking_enabled(kvm))) + if (KVM_BUG_ON(!kvm_page_track_write_tracking_enabled(kvm), kvm)) return; update_gfn_write_track(slot, gfn, -1); -- 2.7.4