From 404e0a19e155e2303a081109f3ae5e625ac8030a Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Thu, 4 Dec 2014 15:11:11 +0100 Subject: KVM: cpuid: mask more bits in leaf 0xd and subleaves MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit - EAX=0Dh, ECX=1: output registers EBX/ECX/EDX are reserved. - EAX=0Dh, ECX>1: output register ECX bit 0 is clear for all the CPUID leaves we support, because variable "supported" comes from XCR0 and not XSS. Bits above 0 are reserved, so ECX is overall zero. Output register EDX is reserved. Source: Intel Architecture Instruction Set Extensions Programming Reference, ref. number 319433-022 Reviewed-by: Radim Krčmář Tested-by: Wanpeng Li Signed-off-by: Paolo Bonzini --- arch/x86/kvm/cpuid.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) (limited to 'arch/x86/kvm') diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c index 2f7bc2de9915..644bfe828ce1 100644 --- a/arch/x86/kvm/cpuid.c +++ b/arch/x86/kvm/cpuid.c @@ -482,8 +482,14 @@ static inline int __do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function, entry[i].ebx = xstate_required_size(supported, true); - } else if (entry[i].eax == 0 || !(supported & mask)) - continue; + } else { + if (entry[i].eax == 0 || !(supported & mask)) + continue; + if (WARN_ON_ONCE(entry[i].ecx & 1)) + continue; + } + entry[i].ecx = 0; + entry[i].edx = 0; entry[i].flags |= KVM_CPUID_FLAG_SIGNIFCANT_INDEX; ++*nent; -- cgit v1.2.3-59-g8ed1b