Return-Path: Message-Id: <20130813155824.616111637@goodmis.org> Date: Tue, 13 Aug 2013 11:57:00 -0400 From: Steven Rostedt To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Zhang Haoyu , Paolo Bonzini Subject: [06/88] KVM: x86: remove vcpus CPL check in host-invoked XCR set References: <20130813155654.069291373@goodmis.org> Content-Disposition: inline; filename=0006-KVM-x86-remove-vcpu-s-CPL-check-in-host-invoked-XCR-.patch Sender: linux-kernel-owner@vger.kernel.org List-ID: 3.6.11.7-rc1 stable review patch. If anyone has any objections, please let me know. ------------------ From: "Zhanghaoyu (A)" [ Upstream commit 764bcbc5a6d7a2f3e75c9f0e4caa984e2926e346 ] __kvm_set_xcr function does the CPL check when set xcr. __kvm_set_xcr is called in two flows, one is invoked by guest, call stack shown as below, handle_xsetbv(or xsetbv_interception) kvm_set_xcr __kvm_set_xcr the other one is invoked by host, for example during system reset: kvm_arch_vcpu_ioctl kvm_vcpu_ioctl_x86_set_xcrs __kvm_set_xcr The former does need the CPL check, but the latter does not. Cc: stable@vger.kernel.org Signed-off-by: Zhang Haoyu Signed-off-by: Steven Rostedt [Tweaks to commit message. - Paolo] Signed-off-by: Paolo Bonzini --- arch/x86/kvm/x86.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index f7a361f..2dcd250 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -558,8 +558,6 @@ int __kvm_set_xcr(struct kvm_vcpu *vcpu, u32 index, u64 xcr) if (index != XCR_XFEATURE_ENABLED_MASK) return 1; xcr0 = xcr; - if (kvm_x86_ops->get_cpl(vcpu) != 0) - return 1; if (!(xcr0 & XSTATE_FP)) return 1; if ((xcr0 & XSTATE_YMM) && !(xcr0 & XSTATE_SSE)) @@ -573,7 +571,8 @@ int __kvm_set_xcr(struct kvm_vcpu *vcpu, u32 index, u64 xcr) int kvm_set_xcr(struct kvm_vcpu *vcpu, u32 index, u64 xcr) { - if (__kvm_set_xcr(vcpu, index, xcr)) { + if (kvm_x86_ops->get_cpl(vcpu) != 0 || + __kvm_set_xcr(vcpu, index, xcr)) { kvm_inject_gp(vcpu, 0); return 1; } -- 1.7.10.4