From: Razvan Cojocaru Date: Mon, 2 Jul 2018 11:08:27 +0000 (+0200) Subject: svm: don't clear interception for MSRs required for introspection X-Git-Tag: archive/raspbian/4.14.0+80-gd101b417b7-1+rpi1^2~63^2~3714 X-Git-Url: https://dgit.raspbian.org/%22http://www.example.com/cgi/%22/%22http:/www.example.com/cgi/%22?a=commitdiff_plain;h=2746088d9cb403470639508cbedbc9b952f7abc4;p=xen.git svm: don't clear interception for MSRs required for introspection This patch mirrors the VMX code that doesn't allow vmx_clear_msr_intercept() to clear interception of MSRs that an introspection agent is trying to monitor. Signed-off-by: Razvan Cojocaru Reviewed-by: Boris Ostrovsky --- diff --git a/xen/arch/x86/hvm/svm/svm.c b/xen/arch/x86/hvm/svm/svm.c index 165500e3f2..bb47f59e4a 100644 --- a/xen/arch/x86/hvm/svm/svm.c +++ b/xen/arch/x86/hvm/svm/svm.c @@ -148,6 +148,7 @@ svm_msrbit(unsigned long *msr_bitmap, uint32_t msr) void svm_intercept_msr(struct vcpu *v, uint32_t msr, int flags) { unsigned long *msr_bit; + const struct domain *d = v->domain; msr_bit = svm_msrbit(v->arch.hvm_svm.msrpm, msr); BUG_ON(msr_bit == NULL); @@ -155,12 +156,12 @@ void svm_intercept_msr(struct vcpu *v, uint32_t msr, int flags) if ( flags & MSR_INTERCEPT_READ ) __set_bit(msr * 2, msr_bit); - else + else if ( !monitored_msr(d, msr) ) __clear_bit(msr * 2, msr_bit); if ( flags & MSR_INTERCEPT_WRITE ) __set_bit(msr * 2 + 1, msr_bit); - else + else if ( !monitored_msr(d, msr) ) __clear_bit(msr * 2 + 1, msr_bit); }