vmm(4): allow reading MSR_TSC on Intel hosts.

Add's MSR_TSC to the read bitmap for msr access. This was added to
AMD/SVM in Feb 2020, but never added to Intel VMX. Some guests use
rdmsr instead of rdtsc, so this prevents a #GP exception.

ok mlarkin@

diff --git a/sys/arch/amd64/amd64/vmm.c b/sys/arch/amd64/amd64/vmm.c
index c3d957c..51378f4 100644 (file)
--- a/sys/arch/amd64/amd64/vmm.c
+++ b/sys/arch/amd64/amd64/vmm.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: vmm.c,v 1.322 2022/09/02 17:46:37 dv Exp $    */
+/*     $OpenBSD: vmm.c,v 1.323 2022/09/07 18:44:09 dv Exp $    */
 /*
  * Copyright (c) 2014 Mike Larkin <mlarkin@openbsd.org>
  *
@@ -3522,7 +3522,9 @@ vcpu_reset_regs_vmx(struct vcpu *vcpu, struct vcpu_reg_state *vrs)
        vmx_setmsrbrw(vcpu, MSR_FSBASE);
        vmx_setmsrbrw(vcpu, MSR_GSBASE);
        vmx_setmsrbrw(vcpu, MSR_KERNELGSBASE);
+       
        vmx_setmsrbr(vcpu, MSR_MISC_ENABLE);
+       vmx_setmsrbr(vcpu, MSR_TSC);
 
        /* XXX CR0 shadow */
        /* XXX CR4 shadow */