From 798f90e005767407a97f68cf5b95168fb44a46b4 Mon Sep 17 00:00:00 2001 From: Jan Beulich Date: Mon, 20 Aug 2012 08:40:01 +0200 Subject: [PATCH] x86: don't expose SYSENTER on unknown CPUs So far we only ever set up the respective MSRs on Intel CPUs, yet we hide the feature only on a 32-bit hypervisor. That prevents booting of PV guests on top of a 64-bit hypervisor making use of the instruction on unknown CPUs (VIA in this case). Signed-off-by: Jan Beulich Acked-by: Keir Fraser --- xen/arch/x86/cpu/common.c | 1 + 1 file changed, 1 insertion(+) diff --git a/xen/arch/x86/cpu/common.c b/xen/arch/x86/cpu/common.c index 186863d131..d066ebbcec 100644 --- a/xen/arch/x86/cpu/common.c +++ b/xen/arch/x86/cpu/common.c @@ -55,6 +55,7 @@ static void default_init(struct cpuinfo_x86 * c) /* Not much we can do here... */ /* Check if at least it has cpuid */ BUG_ON(c->cpuid_level == -1); + __clear_bit(X86_FEATURE_SEP, c->x86_capability); } static struct cpu_dev default_cpu = { -- 2.30.2