[patch 73/88] KVM: x86: disable kvmclock on non constant TSC hosts

Greg KH
2009-04-30T17:41:19Z

[-- Attachment #1: kvm-x86-disable-kvmclock-on-non-constant-tsc-hosts.patch --]
[-- Type: text/plain, Size: 1122 bytes --]

2.6.28-stable review patch. If anyone has any objections, please let us know.

------------------

(cherry picked from abe6655dd699069b53bcccbc65b2717f60203b12)

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>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---
arch/x86/kvm/x86.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -906,7 +906,6 @@ int kvm_dev_ioctl_check_extension(long e
case KVM_CAP_USER_MEMORY:
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:
@@ -931,6 +930,9 @@ int kvm_dev_ioctl_check_extension(long e
case KVM_CAP_IOMMU:
r = intel_iommu_found();
break;
+ case KVM_CAP_CLOCKSOURCE:
+ r = boot_cpu_has(X86_FEATURE_CONSTANT_TSC);
+ break;
default:
r = 0;
break;