diff options
| author | Sean Christopherson <seanjc@google.com> | 2021-09-20 17:02:55 -0700 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2021-09-22 10:33:08 -0400 |
| commit | 03a6e84069d1870f5b3d360e64cb330b66f76dee (patch) | |
| tree | 62f084ef70a2ab09013c1d7c6f3abbfae2124103 /arch | |
| parent | 7117003fe4e3c8977744f2ad33bb95fd3e10023f (diff) | |
KVM: x86: Clear KVM's cached guest CR3 at RESET/INIT
Explicitly zero the guest's CR3 and mark it available+dirty at RESET/INIT.
Per Intel's SDM and AMD's APM, CR3 is zeroed at both RESET and INIT. For
RESET, this is a nop as vcpu is zero-allocated. For INIT, the bug has
likely escaped notice because no firmware/kernel puts its page tables root
at PA=0, let alone relies on INIT to get the desired CR3 for such page
tables.
Cc: stable@vger.kernel.org
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20210921000303.400537-3-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/x86/kvm/x86.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 06026f3d7ea2..8a83dd1b882e 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -10895,6 +10895,9 @@ void kvm_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event) kvm_set_rflags(vcpu, X86_EFLAGS_FIXED); kvm_rip_write(vcpu, 0xfff0); + vcpu->arch.cr3 = 0; + kvm_register_mark_dirty(vcpu, VCPU_EXREG_CR3); + /* * CR0.CD/NW are set on RESET, preserved on INIT. Note, some versions * of Intel's SDM list CD/NW as being set on INIT, but they contradict |