[PATCH 0/2] Some KVM fixes

[PATCH 0/2] Some KVM fixes

[Joerg Roedel]

Hi,

these two patches fix one issue introduced with the recent
emulator-intercept code (the issue was there before too, but
hidden by other workaround code which was removed in the
mentioned patch-set).
The second patch fixes a problem introduced with the tsc-scaling
patch-set where the TSC was not usable anymore after a
guest-reboot.
All-in-all, these fixes are no -stable material.

Regards,

	Joerg

Diffstat:

 arch/x86/include/asm/kvm_host.h |    1 -
 arch/x86/kvm/svm.c              |    3 +++
 arch/x86/kvm/x86.c              |    2 +-
 3 files changed, 4 insertions(+), 2 deletions(-)

Shortlog:

Joerg Roedel (2):
      KVM: SVM: Fix nested sel_cr0 intercept path with decode-assists
      KVM: X86: Update last_guest_tsc in vcpu_put

[PATCH 1/2] KVM: SVM: Fix nested sel_cr0 intercept path with decode-assists

[Joerg Roedel]

This patch fixes a bug in the nested-svm path when
decode-assists is available on the machine. After a
selective-cr0 intercept is detected the rip is advanced
unconditionally. This causes the l1-guest to continue
running with an l2-rip.
This bug was with the sel_cr0 unit-test on decode-assists
capable hardware.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
---
 arch/x86/kvm/svm.c |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)

diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index a6bf2ad..de4bba9 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -2799,6 +2799,9 @@ static int cr_interception(struct vcpu_svm *svm)
 		case 0:
 			if (!check_selective_cr0_intercepted(svm, val))
 				err = kvm_set_cr0(&svm->vcpu, val);
+			else
+				return 1;
+
 			break;
 		case 3:
 			err = kvm_set_cr3(&svm->vcpu, val);
-- 
1.7.1

[PATCH 2/2] KVM: X86: Update last_guest_tsc in vcpu_put

[Joerg Roedel]

The last_guest_tsc is used in vcpu_load to adjust the
tsc_offset since tsc-scaling is merged. So the
last_guest_tsc needs to be updated in vcpu_put instead of
the the last_host_tsc. This is fixed with this patch.

Reported-by: Jan Kiszka <jan.kiszka@web.de>
Tested-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
---
 arch/x86/include/asm/kvm_host.h |    1 -
 arch/x86/kvm/x86.c              |    2 +-
 2 files changed, 1 insertions(+), 2 deletions(-)

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index bd57639..d7282ef 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -391,7 +391,6 @@ struct kvm_vcpu_arch {
 	unsigned int hw_tsc_khz;
 	unsigned int time_offset;
 	struct page *time_page;
-	u64 last_host_tsc;
 	u64 last_guest_tsc;
 	u64 last_kernel_ns;
 	u64 last_tsc_nsec;
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 1d5a7f4..d8277aa 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -2146,7 +2146,7 @@ void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
 {
 	kvm_x86_ops->vcpu_put(vcpu);
 	kvm_put_guest_fpu(vcpu);
-	vcpu->arch.last_host_tsc = native_read_tsc();
+	kvm_get_msr(vcpu, MSR_IA32_TSC, &vcpu->arch.last_guest_tsc);
 }
 
 static int is_efer_nx(void)
-- 
1.7.1

Re: [PATCH 0/2] Some KVM fixes

[Avi Kivity]

On 04/18/2011 12:42 PM, Joerg Roedel wrote:
> Hi,
>
> these two patches fix one issue introduced with the recent
> emulator-intercept code (the issue was there before too, but
> hidden by other workaround code which was removed in the
> mentioned patch-set).
> The second patch fixes a problem introduced with the tsc-scaling
> patch-set where the TSC was not usable anymore after a
> guest-reboot.
> All-in-all, these fixes are no -stable material.

Applied, thanks.

-- 
error compiling committee.c: too many arguments to function