From 585df9100649b5038250e1c33cf8af019a77844c Mon Sep 17 00:00:00 2001 From: Liran Alon Date: Sun, 5 Nov 2017 16:56:34 +0200 Subject: [PATCH 05/33] KVM: x86: Don't re-execute instruction when not passing CR2 value MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit [ Upstream commit 9b8ae63798cb97e785a667ff27e43fa6220cb734 ] In case of instruction-decode failure or emulation failure, x86_emulate_instruction() will call reexecute_instruction() which will attempt to use the cr2 value passed to x86_emulate_instruction(). However, when x86_emulate_instruction() is called from emulate_instruction(), cr2 is not passed (passed as 0) and therefore it doesn't make sense to execute reexecute_instruction() logic at all. Fixes: 51d8b66199e9 ("KVM: cleanup emulate_instruction") Signed-off-by: Liran Alon Reviewed-by: Nikita Leshenko Reviewed-by: Konrad Rzeszutek Wilk Signed-off-by: Konrad Rzeszutek Wilk Reviewed-by: Wanpeng Li Signed-off-by: Radim Krčmář Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- arch/x86/include/asm/kvm_host.h | 3 ++- arch/x86/kvm/vmx.c | 2 +- 2 files changed, 3 insertions(+), 2 deletions(-) diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index bdde807..6f6ee68 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -1113,7 +1113,8 @@ int x86_emulate_instruction(struct kvm_vcpu *vcpu, unsigned long cr2, static inline int emulate_instruction(struct kvm_vcpu *vcpu, int emulation_type) { - return x86_emulate_instruction(vcpu, 0, emulation_type, NULL, 0); + return x86_emulate_instruction(vcpu, 0, + emulation_type | EMULTYPE_NO_REEXECUTE, NULL, 0); } void kvm_enable_efer_bits(u64); diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index ee766c2..8e5001d 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -6232,7 +6232,7 @@ static int handle_invalid_guest_state(struct kvm_vcpu *vcpu) if (test_bit(KVM_REQ_EVENT, &vcpu->requests)) return 1; - err = emulate_instruction(vcpu, EMULTYPE_NO_REEXECUTE); + err = emulate_instruction(vcpu, 0); if (err == EMULATE_USER_EXIT) { ++vcpu->stat.mmio_exits; -- 2.7.4