KVM: x86: disable kvmclock on non constant TSC hosts

This is better.

Currently, this code path is posing us big troubles,
and we won't have a decent patch in time. So, temporarily
disable it.

Signed-off-by: Glauber Costa <glommer@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index fc3e329..758b7a1 100644 (file)
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -967,7 +967,6 @@ int kvm_dev_ioctl_check_extension(long ext)
        case KVM_CAP_MMU_SHADOW_CACHE_CONTROL:
        case KVM_CAP_SET_TSS_ADDR:
        case KVM_CAP_EXT_CPUID:
-       case KVM_CAP_CLOCKSOURCE:
        case KVM_CAP_PIT:
        case KVM_CAP_NOP_IO_DELAY:
        case KVM_CAP_MP_STATE:
@@ -992,6 +991,9 @@ int kvm_dev_ioctl_check_extension(long ext)
        case KVM_CAP_IOMMU:
                r = iommu_found();
                break;
+       case KVM_CAP_CLOCKSOURCE:
+               r = boot_cpu_has(X86_FEATURE_CONSTANT_TSC);
+               break;
        default:
                r = 0;
                break;