From 265cc29f0df45f7ddb6432eaa35cfd5410a78e2c Mon Sep 17 00:00:00 2001 From: Hao Xiang Date: Fri, 15 Oct 2021 19:59:21 +0800 Subject: [PATCH] KVM: VMX: Remove redundant handling of bus lock vmexit mainline inclusion from mainline-v5.15-rc7 commit d61863c66f9b443192997613cd6aeca3f65cc313 category: feature feature: KVM Bus Lock VM Exit bugzilla: https://gitee.com/openeuler/intel-kernel/issues/I5RJCB CVE: N/A Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/ commit/?id=d61863c66f9b443192997613cd6aeca3f65cc313 Intel-SIG: commit d61863c66f9b ("KVM: VMX: Remove redundant handling of bus lock vmexit") ------------------------------------- KVM: VMX: Remove redundant handling of bus lock vmexit Hardware may or may not set exit_reason.bus_lock_detected on BUS_LOCK VM-Exits. Dealing with KVM_RUN_X86_BUS_LOCK in handle_bus_lock_vmexit could be redundant when exit_reason.basic is EXIT_REASON_BUS_LOCK. We can remove redundant handling of bus lock vmexit. Unconditionally Set exit_reason.bus_lock_detected in handle_bus_lock_vmexit(), and deal with KVM_RUN_X86_BUS_LOCK only in vmx_handle_exit(). Signed-off-by: Hao Xiang Message-Id: <1634299161-30101-1-git-send-email-hao.xiang@linux.alibaba.com> Signed-off-by: Paolo Bonzini Signed-off-by: Aichun Shi --- arch/x86/kvm/vmx/vmx.c | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-) diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index 2feb986114b7..2c79f617e296 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -5949,9 +5949,13 @@ static int handle_encls(struct kvm_vcpu *vcpu) static int handle_bus_lock_vmexit(struct kvm_vcpu *vcpu) { - vcpu->run->exit_reason = KVM_EXIT_X86_BUS_LOCK; - vcpu->run->flags |= KVM_RUN_X86_BUS_LOCK; - return 0; + /* + * Hardware may or may not set the BUS_LOCK_DETECTED flag on BUS_LOCK + * VM-Exits. Unconditionally set the flag here and leave the handling to + * vmx_handle_exit(). + */ + to_vmx(vcpu)->exit_reason.bus_lock_detected = true; + return 1; } /* @@ -6427,9 +6431,8 @@ static int vmx_handle_exit(struct kvm_vcpu *vcpu, fastpath_t exit_fastpath) int ret = __vmx_handle_exit(vcpu, exit_fastpath); /* - * Even when current exit reason is handled by KVM internally, we - * still need to exit to user space when bus lock detected to inform - * that there is a bus lock in guest. + * Exit to user space when bus lock detected to inform that there is + * a bus lock in guest. */ if (to_vmx(vcpu)->exit_reason.bus_lock_detected) { if (ret > 0) -- GitLab