From 849cc9ac56eff8a8d575ed9f484aad72f383862c Mon Sep 17 00:00:00 2001 From: Jan Beulich Date: Tue, 22 May 2018 05:40:02 -0600 Subject: [PATCH] libxc/x86/PV: don't hand through CPUID leaf 0x80000008 as is Just like for HVM the feature set should be used for EBX output, while EAX should be restricted to the low 16 bits and ECX/EDX should be zero. Signed-off-by: Jan Beulich Reviewed-by: Andrew Cooper --- tools/libxc/xc_cpuid_x86.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/tools/libxc/xc_cpuid_x86.c b/tools/libxc/xc_cpuid_x86.c index 9fa2f7c360..21537f06f1 100644 --- a/tools/libxc/xc_cpuid_x86.c +++ b/tools/libxc/xc_cpuid_x86.c @@ -575,6 +575,12 @@ static void xc_cpuid_pv_policy(xc_interface *xch, break; } + case 0x80000008: + regs[0] &= 0x0000ffffu; + regs[1] = info->featureset[featureword_of(X86_FEATURE_CLZERO)]; + regs[2] = regs[3] = 0; + break; + case 0x00000005: /* MONITOR/MWAIT */ case 0x0000000b: /* Extended Topology Enumeration */ case 0x8000000a: /* SVM revision and features */ -- 2.39.5