[PATCH 3.12 81/88] KVM: x86: expose invariant tsc cpuid bit (v2)

[Jiri Slaby]

From: Marcelo Tosatti <mtosa...@redhat.com>

3.12-stable review patch.  If anyone has any objections, please let me know.

===============

commit e4c9a5a17567f8ea975bdcfdd1bf9d63965de6c9 upstream.

Invariant TSC is a property of TSC, no additional
support code necessary.

Signed-off-by: Marcelo Tosatti <mtosa...@redhat.com>
Signed-off-by: Paolo Bonzini <pbonz...@redhat.com>
Signed-off-by: Jiri Slaby <jsl...@suse.cz>
---
 arch/x86/kvm/cpuid.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
index b132551528e5..6620ac307215 100644
--- a/arch/x86/kvm/cpuid.c
+++ b/arch/x86/kvm/cpuid.c
@@ -437,6 +437,13 @@ static int do_cpuid_ent(struct kvm_cpuid_entry2 *entry, 
u32 function,
                entry->ecx &= kvm_supported_word6_x86_features;
                cpuid_mask(&entry->ecx, 6);
                break;
+       case 0x80000007: /* Advanced power management */
+               /* invariant TSC is CPUID.80000007H:EDX[8] */
+               entry->edx &= (1 << 8);
+               /* mask against host */
+               entry->edx &= boot_cpu_data.x86_power;
+               entry->eax = entry->ebx = entry->ecx = 0;
+               break;
        case 0x80000008: {
                unsigned g_phys_as = (entry->eax >> 16) & 0xff;
                unsigned virt_as = max((entry->eax >> 8) & 0xff, 48U);
@@ -467,7 +474,6 @@ static int do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 
function,
        case 3: /* Processor serial number */
        case 5: /* MONITOR/MWAIT */
        case 6: /* Thermal management */
-       case 0x80000007: /* Advanced power management */
        case 0xC0000002:
        case 0xC0000003:
        case 0xC0000004:
-- 
2.9.1