From: brynet <brynet@openbsd.org>
Date: Thu, 20 Sep 2018 14:32:59 +0000 (+0000)
Subject: vmm(4): Clear the guest MWAITX/MONITORX extended CPUID feature bit,
X-Git-Url: http://artulab.com/gitweb/?a=commitdiff_plain;h=927beb9ef36d476c345f2bc76ff4380453aa6c03;p=openbsd

vmm(4): Clear the guest MWAITX/MONITORX extended CPUID feature bit,
like we already do for MWAIT/MONITOR. Also match Intel here by not
exposing the SVM capability to AMD guests.

Allows Linux guests to boot in vmd(8) on Ryzen CPUs.

ok mlarkin@
---

diff --git a/sys/arch/amd64/amd64/vmm.c b/sys/arch/amd64/amd64/vmm.c
index 34c5651a021..266a5333e56 100644
--- a/sys/arch/amd64/amd64/vmm.c
+++ b/sys/arch/amd64/amd64/vmm.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: vmm.c,v 1.219 2018/08/21 19:04:38 deraadt Exp $	*/
+/*	$OpenBSD: vmm.c,v 1.220 2018/09/20 14:32:59 brynet Exp $	*/
 /*
  * Copyright (c) 2014 Mike Larkin <mlarkin@openbsd.org>
  *
@@ -6146,7 +6146,7 @@ vmm_handle_cpuid(struct vcpu *vcpu)
 	case 0x80000001: 	/* Extended function info */
 		*rax = curcpu()->ci_efeature_eax;
 		*rbx = 0;	/* Reserved */
-		*rcx = curcpu()->ci_efeature_ecx;
+		*rcx = curcpu()->ci_efeature_ecx & VMM_ECPUIDECX_MASK;
 		*rdx = curcpu()->ci_feature_eflags & VMM_FEAT_EFLAGS_MASK;
 		break;
 	case 0x80000002:	/* Brand string */
diff --git a/sys/arch/amd64/include/vmmvar.h b/sys/arch/amd64/include/vmmvar.h
index fcbbb987cd6..812e660f5f2 100644
--- a/sys/arch/amd64/include/vmmvar.h
+++ b/sys/arch/amd64/include/vmmvar.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: vmmvar.h,v 1.58 2018/08/21 19:04:40 deraadt Exp $	*/
+/*	$OpenBSD: vmmvar.h,v 1.59 2018/09/20 14:32:59 brynet Exp $	*/
 /*
  * Copyright (c) 2014 Mike Larkin <mlarkin@openbsd.org>
  *
@@ -548,8 +548,8 @@ struct vm_rwregs_params {
 /*
  * clone host capabilities minus:
  *  debug store (CPUIDECX_DTES64, CPUIDECX_DSCPL, CPUID_DS)
- *  monitor/mwait (CPUIDECX_MWAIT)
- *  vmx (CPUIDECX_VMX)
+ *  monitor/mwait (CPUIDECX_MWAIT, CPUIDECX_MWAITX)
+ *  vmx/svm (CPUIDECX_VMX, CPUIDECX_SVM)
  *  smx (CPUIDECX_SMX)
  *  speedstep (CPUIDECX_EST)
  *  thermal (CPUIDECX_TM2, CPUID_ACPI, CPUID_TM)
@@ -573,6 +573,7 @@ struct vm_rwregs_params {
     CPUIDECX_DSCPL | CPUIDECX_SMX | CPUIDECX_CNXTID | \
     CPUIDECX_SDBG | CPUIDECX_XTPR | CPUIDECX_PCID | \
     CPUIDECX_DCA | CPUIDECX_X2APIC | CPUIDECX_DEADLINE)
+#define VMM_ECPUIDECX_MASK ~(CPUIDECX_SVM | CPUIDECX_MWAITX)
 #define VMM_CPUIDEDX_MASK ~(CPUID_ACPI | CPUID_TM | \
     CPUID_HTT | CPUID_DS | CPUID_APIC | \
     CPUID_PSN | CPUID_SS | CPUID_PBE | \