Re: [PATCH 2/2] Revert "KVM: x86: zero kvmclock_offset when vcpu0 initializes kvmclock system MSR"

2015-09-23 Thread Marcelo Tosatti 
On Tue, Sep 22, 2015 at 09:52:49PM +0200, Paolo Bonzini wrote:
> 
> 
> On 22/09/2015 21:01, Marcelo Tosatti wrote:
> > On Fri, Sep 18, 2015 at 05:54:30PM +0200, Radim Krčmář wrote:
> >> Shifting pvclock_vcpu_time_info.system_time on write to KVM system time
> >> MSR is a change of ABI.  Probably only 2.6.16 based SLES 10 breaks due
> >> to its custom enhancements to kvmclock, but KVM never declared the MSR
> >> only for one-shot initialization.  (Doc says that only one write is
> >> needed.)
> >>
> >> This reverts commit b7e60c5aedd2b63f16ef06fde4f81ca032211bc5.
> >> And adds a note to the definition of PVCLOCK_COUNTS_FROM_ZERO.
> >>
> >> Signed-off-by: Radim Krčmář 
> >> ---
> >>  arch/x86/include/asm/pvclock-abi.h | 1 +
> >>  arch/x86/kvm/x86.c | 4 
> >>  2 files changed, 1 insertion(+), 4 deletions(-)
> >>
> >> diff --git a/arch/x86/include/asm/pvclock-abi.h 
> >> b/arch/x86/include/asm/pvclock-abi.h
> >> index 655e07a48f6c..67f08230103a 100644
> >> --- a/arch/x86/include/asm/pvclock-abi.h
> >> +++ b/arch/x86/include/asm/pvclock-abi.h
> >> @@ -41,6 +41,7 @@ struct pvclock_wall_clock {
> >>  
> >>  #define PVCLOCK_TSC_STABLE_BIT(1 << 0)
> >>  #define PVCLOCK_GUEST_STOPPED (1 << 1)
> >> +/* PVCLOCK_COUNTS_FROM_ZERO broke ABI and can't be used anymore. */
> >>  #define PVCLOCK_COUNTS_FROM_ZERO (1 << 2)
> >>  #endif /* __ASSEMBLY__ */
> >>  #endif /* _ASM_X86_PVCLOCK_ABI_H */
> >> diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
> >> index 18d59b584dee..34d33f4757d2 100644
> >> --- a/arch/x86/kvm/x86.c
> >> +++ b/arch/x86/kvm/x86.c
> >> @@ -1707,8 +1707,6 @@ static int kvm_guest_time_update(struct kvm_vcpu *v)
> >>vcpu->pvclock_set_guest_stopped_request = false;
> >>}
> >>  
> >> -  pvclock_flags |= PVCLOCK_COUNTS_FROM_ZERO;
> >> -
> >>/* If the host uses TSC clocksource, then it is stable */
> >>if (use_master_clock)
> >>pvclock_flags |= PVCLOCK_TSC_STABLE_BIT;
> >> @@ -2006,8 +2004,6 @@ int kvm_set_msr_common(struct kvm_vcpu *vcpu, struct 
> >> msr_data *msr_info)
> >>>requests);
> >>  
> >>ka->boot_vcpu_runs_old_kvmclock = tmp;
> >> -
> >> -  ka->kvmclock_offset = -get_kernel_ns();
> >>}
> >>  
> >>vcpu->arch.time = data;
> >> -- 
> >> 2.5.2
> > 
> > ACK
> 
> So I suppose you changed your mind :) but can you explain the reasoning?
> 
> Paolo

The patch is correct. Overflow (issue raised) is only an issue 
without PVCLOCK_TSC_STABLE_BIT.

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Re: [PATCH 2/2] Revert "KVM: x86: zero kvmclock_offset when vcpu0 initializes kvmclock system MSR"

2015-09-23 Thread Marcelo Tosatti 
On Tue, Sep 22, 2015 at 09:52:49PM +0200, Paolo Bonzini wrote:
> 
> 
> On 22/09/2015 21:01, Marcelo Tosatti wrote:
> > On Fri, Sep 18, 2015 at 05:54:30PM +0200, Radim Krčmář wrote:
> >> Shifting pvclock_vcpu_time_info.system_time on write to KVM system time
> >> MSR is a change of ABI.  Probably only 2.6.16 based SLES 10 breaks due
> >> to its custom enhancements to kvmclock, but KVM never declared the MSR
> >> only for one-shot initialization.  (Doc says that only one write is
> >> needed.)
> >>
> >> This reverts commit b7e60c5aedd2b63f16ef06fde4f81ca032211bc5.
> >> And adds a note to the definition of PVCLOCK_COUNTS_FROM_ZERO.
> >>
> >> Signed-off-by: Radim Krčmář 
> >> ---
> >>  arch/x86/include/asm/pvclock-abi.h | 1 +
> >>  arch/x86/kvm/x86.c | 4 
> >>  2 files changed, 1 insertion(+), 4 deletions(-)
> >>
> >> diff --git a/arch/x86/include/asm/pvclock-abi.h 
> >> b/arch/x86/include/asm/pvclock-abi.h
> >> index 655e07a48f6c..67f08230103a 100644
> >> --- a/arch/x86/include/asm/pvclock-abi.h
> >> +++ b/arch/x86/include/asm/pvclock-abi.h
> >> @@ -41,6 +41,7 @@ struct pvclock_wall_clock {
> >>  
> >>  #define PVCLOCK_TSC_STABLE_BIT(1 << 0)
> >>  #define PVCLOCK_GUEST_STOPPED (1 << 1)
> >> +/* PVCLOCK_COUNTS_FROM_ZERO broke ABI and can't be used anymore. */
> >>  #define PVCLOCK_COUNTS_FROM_ZERO (1 << 2)
> >>  #endif /* __ASSEMBLY__ */
> >>  #endif /* _ASM_X86_PVCLOCK_ABI_H */
> >> diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
> >> index 18d59b584dee..34d33f4757d2 100644
> >> --- a/arch/x86/kvm/x86.c
> >> +++ b/arch/x86/kvm/x86.c
> >> @@ -1707,8 +1707,6 @@ static int kvm_guest_time_update(struct kvm_vcpu *v)
> >>vcpu->pvclock_set_guest_stopped_request = false;
> >>}
> >>  
> >> -  pvclock_flags |= PVCLOCK_COUNTS_FROM_ZERO;
> >> -
> >>/* If the host uses TSC clocksource, then it is stable */
> >>if (use_master_clock)
> >>pvclock_flags |= PVCLOCK_TSC_STABLE_BIT;
> >> @@ -2006,8 +2004,6 @@ int kvm_set_msr_common(struct kvm_vcpu *vcpu, struct 
> >> msr_data *msr_info)
> >>>requests);
> >>  
> >>ka->boot_vcpu_runs_old_kvmclock = tmp;
> >> -
> >> -  ka->kvmclock_offset = -get_kernel_ns();
> >>}
> >>  
> >>vcpu->arch.time = data;
> >> -- 
> >> 2.5.2
> > 
> > ACK
> 
> So I suppose you changed your mind :) but can you explain the reasoning?
> 
> Paolo

The patch is correct. Overflow (issue raised) is only an issue 
without PVCLOCK_TSC_STABLE_BIT.

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Re: [PATCH 2/2] Revert "KVM: x86: zero kvmclock_offset when vcpu0 initializes kvmclock system MSR"

2015-09-22 Thread Paolo Bonzini 


On 22/09/2015 21:01, Marcelo Tosatti wrote:
> On Fri, Sep 18, 2015 at 05:54:30PM +0200, Radim Krčmář wrote:
>> Shifting pvclock_vcpu_time_info.system_time on write to KVM system time
>> MSR is a change of ABI.  Probably only 2.6.16 based SLES 10 breaks due
>> to its custom enhancements to kvmclock, but KVM never declared the MSR
>> only for one-shot initialization.  (Doc says that only one write is
>> needed.)
>>
>> This reverts commit b7e60c5aedd2b63f16ef06fde4f81ca032211bc5.
>> And adds a note to the definition of PVCLOCK_COUNTS_FROM_ZERO.
>>
>> Signed-off-by: Radim Krčmář 
>> ---
>>  arch/x86/include/asm/pvclock-abi.h | 1 +
>>  arch/x86/kvm/x86.c | 4 
>>  2 files changed, 1 insertion(+), 4 deletions(-)
>>
>> diff --git a/arch/x86/include/asm/pvclock-abi.h 
>> b/arch/x86/include/asm/pvclock-abi.h
>> index 655e07a48f6c..67f08230103a 100644
>> --- a/arch/x86/include/asm/pvclock-abi.h
>> +++ b/arch/x86/include/asm/pvclock-abi.h
>> @@ -41,6 +41,7 @@ struct pvclock_wall_clock {
>>  
>>  #define PVCLOCK_TSC_STABLE_BIT  (1 << 0)
>>  #define PVCLOCK_GUEST_STOPPED   (1 << 1)
>> +/* PVCLOCK_COUNTS_FROM_ZERO broke ABI and can't be used anymore. */
>>  #define PVCLOCK_COUNTS_FROM_ZERO (1 << 2)
>>  #endif /* __ASSEMBLY__ */
>>  #endif /* _ASM_X86_PVCLOCK_ABI_H */
>> diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
>> index 18d59b584dee..34d33f4757d2 100644
>> --- a/arch/x86/kvm/x86.c
>> +++ b/arch/x86/kvm/x86.c
>> @@ -1707,8 +1707,6 @@ static int kvm_guest_time_update(struct kvm_vcpu *v)
>>  vcpu->pvclock_set_guest_stopped_request = false;
>>  }
>>  
>> -pvclock_flags |= PVCLOCK_COUNTS_FROM_ZERO;
>> -
>>  /* If the host uses TSC clocksource, then it is stable */
>>  if (use_master_clock)
>>  pvclock_flags |= PVCLOCK_TSC_STABLE_BIT;
>> @@ -2006,8 +2004,6 @@ int kvm_set_msr_common(struct kvm_vcpu *vcpu, struct 
>> msr_data *msr_info)
>>  >requests);
>>  
>>  ka->boot_vcpu_runs_old_kvmclock = tmp;
>> -
>> -ka->kvmclock_offset = -get_kernel_ns();
>>  }
>>  
>>  vcpu->arch.time = data;
>> -- 
>> 2.5.2
> 
> ACK

So I suppose you changed your mind :) but can you explain the reasoning?

Paolo
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Re: [PATCH 2/2] Revert "KVM: x86: zero kvmclock_offset when vcpu0 initializes kvmclock system MSR"

2015-09-22 Thread Marcelo Tosatti 
On Fri, Sep 18, 2015 at 05:54:30PM +0200, Radim Krčmář wrote:
> Shifting pvclock_vcpu_time_info.system_time on write to KVM system time
> MSR is a change of ABI.  Probably only 2.6.16 based SLES 10 breaks due
> to its custom enhancements to kvmclock, but KVM never declared the MSR
> only for one-shot initialization.  (Doc says that only one write is
> needed.)
> 
> This reverts commit b7e60c5aedd2b63f16ef06fde4f81ca032211bc5.
> And adds a note to the definition of PVCLOCK_COUNTS_FROM_ZERO.
> 
> Signed-off-by: Radim Krčmář 
> ---
>  arch/x86/include/asm/pvclock-abi.h | 1 +
>  arch/x86/kvm/x86.c | 4 
>  2 files changed, 1 insertion(+), 4 deletions(-)
> 
> diff --git a/arch/x86/include/asm/pvclock-abi.h 
> b/arch/x86/include/asm/pvclock-abi.h
> index 655e07a48f6c..67f08230103a 100644
> --- a/arch/x86/include/asm/pvclock-abi.h
> +++ b/arch/x86/include/asm/pvclock-abi.h
> @@ -41,6 +41,7 @@ struct pvclock_wall_clock {
>  
>  #define PVCLOCK_TSC_STABLE_BIT   (1 << 0)
>  #define PVCLOCK_GUEST_STOPPED(1 << 1)
> +/* PVCLOCK_COUNTS_FROM_ZERO broke ABI and can't be used anymore. */
>  #define PVCLOCK_COUNTS_FROM_ZERO (1 << 2)
>  #endif /* __ASSEMBLY__ */
>  #endif /* _ASM_X86_PVCLOCK_ABI_H */
> diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
> index 18d59b584dee..34d33f4757d2 100644
> --- a/arch/x86/kvm/x86.c
> +++ b/arch/x86/kvm/x86.c
> @@ -1707,8 +1707,6 @@ static int kvm_guest_time_update(struct kvm_vcpu *v)
>   vcpu->pvclock_set_guest_stopped_request = false;
>   }
>  
> - pvclock_flags |= PVCLOCK_COUNTS_FROM_ZERO;
> -
>   /* If the host uses TSC clocksource, then it is stable */
>   if (use_master_clock)
>   pvclock_flags |= PVCLOCK_TSC_STABLE_BIT;
> @@ -2006,8 +2004,6 @@ int kvm_set_msr_common(struct kvm_vcpu *vcpu, struct 
> msr_data *msr_info)
>   >requests);
>  
>   ka->boot_vcpu_runs_old_kvmclock = tmp;
> -
> - ka->kvmclock_offset = -get_kernel_ns();
>   }
>  
>   vcpu->arch.time = data;
> -- 
> 2.5.2

ACK

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Re: [PATCH 2/2] Revert "KVM: x86: zero kvmclock_offset when vcpu0 initializes kvmclock system MSR"

2015-09-22 Thread Paolo Bonzini 


On 22/09/2015 21:01, Marcelo Tosatti wrote:
> On Fri, Sep 18, 2015 at 05:54:30PM +0200, Radim Krčmář wrote:
>> Shifting pvclock_vcpu_time_info.system_time on write to KVM system time
>> MSR is a change of ABI.  Probably only 2.6.16 based SLES 10 breaks due
>> to its custom enhancements to kvmclock, but KVM never declared the MSR
>> only for one-shot initialization.  (Doc says that only one write is
>> needed.)
>>
>> This reverts commit b7e60c5aedd2b63f16ef06fde4f81ca032211bc5.
>> And adds a note to the definition of PVCLOCK_COUNTS_FROM_ZERO.
>>
>> Signed-off-by: Radim Krčmář 
>> ---
>>  arch/x86/include/asm/pvclock-abi.h | 1 +
>>  arch/x86/kvm/x86.c | 4 
>>  2 files changed, 1 insertion(+), 4 deletions(-)
>>
>> diff --git a/arch/x86/include/asm/pvclock-abi.h 
>> b/arch/x86/include/asm/pvclock-abi.h
>> index 655e07a48f6c..67f08230103a 100644
>> --- a/arch/x86/include/asm/pvclock-abi.h
>> +++ b/arch/x86/include/asm/pvclock-abi.h
>> @@ -41,6 +41,7 @@ struct pvclock_wall_clock {
>>  
>>  #define PVCLOCK_TSC_STABLE_BIT  (1 << 0)
>>  #define PVCLOCK_GUEST_STOPPED   (1 << 1)
>> +/* PVCLOCK_COUNTS_FROM_ZERO broke ABI and can't be used anymore. */
>>  #define PVCLOCK_COUNTS_FROM_ZERO (1 << 2)
>>  #endif /* __ASSEMBLY__ */
>>  #endif /* _ASM_X86_PVCLOCK_ABI_H */
>> diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
>> index 18d59b584dee..34d33f4757d2 100644
>> --- a/arch/x86/kvm/x86.c
>> +++ b/arch/x86/kvm/x86.c
>> @@ -1707,8 +1707,6 @@ static int kvm_guest_time_update(struct kvm_vcpu *v)
>>  vcpu->pvclock_set_guest_stopped_request = false;
>>  }
>>  
>> -pvclock_flags |= PVCLOCK_COUNTS_FROM_ZERO;
>> -
>>  /* If the host uses TSC clocksource, then it is stable */
>>  if (use_master_clock)
>>  pvclock_flags |= PVCLOCK_TSC_STABLE_BIT;
>> @@ -2006,8 +2004,6 @@ int kvm_set_msr_common(struct kvm_vcpu *vcpu, struct 
>> msr_data *msr_info)
>>  >requests);
>>  
>>  ka->boot_vcpu_runs_old_kvmclock = tmp;
>> -
>> -ka->kvmclock_offset = -get_kernel_ns();
>>  }
>>  
>>  vcpu->arch.time = data;
>> -- 
>> 2.5.2
> 
> ACK

So I suppose you changed your mind :) but can you explain the reasoning?

Paolo
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Re: [PATCH 2/2] Revert "KVM: x86: zero kvmclock_offset when vcpu0 initializes kvmclock system MSR"

2015-09-22 Thread Marcelo Tosatti 
On Fri, Sep 18, 2015 at 05:54:30PM +0200, Radim Krčmář wrote:
> Shifting pvclock_vcpu_time_info.system_time on write to KVM system time
> MSR is a change of ABI.  Probably only 2.6.16 based SLES 10 breaks due
> to its custom enhancements to kvmclock, but KVM never declared the MSR
> only for one-shot initialization.  (Doc says that only one write is
> needed.)
> 
> This reverts commit b7e60c5aedd2b63f16ef06fde4f81ca032211bc5.
> And adds a note to the definition of PVCLOCK_COUNTS_FROM_ZERO.
> 
> Signed-off-by: Radim Krčmář 
> ---
>  arch/x86/include/asm/pvclock-abi.h | 1 +
>  arch/x86/kvm/x86.c | 4 
>  2 files changed, 1 insertion(+), 4 deletions(-)
> 
> diff --git a/arch/x86/include/asm/pvclock-abi.h 
> b/arch/x86/include/asm/pvclock-abi.h
> index 655e07a48f6c..67f08230103a 100644
> --- a/arch/x86/include/asm/pvclock-abi.h
> +++ b/arch/x86/include/asm/pvclock-abi.h
> @@ -41,6 +41,7 @@ struct pvclock_wall_clock {
>  
>  #define PVCLOCK_TSC_STABLE_BIT   (1 << 0)
>  #define PVCLOCK_GUEST_STOPPED(1 << 1)
> +/* PVCLOCK_COUNTS_FROM_ZERO broke ABI and can't be used anymore. */
>  #define PVCLOCK_COUNTS_FROM_ZERO (1 << 2)
>  #endif /* __ASSEMBLY__ */
>  #endif /* _ASM_X86_PVCLOCK_ABI_H */
> diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
> index 18d59b584dee..34d33f4757d2 100644
> --- a/arch/x86/kvm/x86.c
> +++ b/arch/x86/kvm/x86.c
> @@ -1707,8 +1707,6 @@ static int kvm_guest_time_update(struct kvm_vcpu *v)
>   vcpu->pvclock_set_guest_stopped_request = false;
>   }
>  
> - pvclock_flags |= PVCLOCK_COUNTS_FROM_ZERO;
> -
>   /* If the host uses TSC clocksource, then it is stable */
>   if (use_master_clock)
>   pvclock_flags |= PVCLOCK_TSC_STABLE_BIT;
> @@ -2006,8 +2004,6 @@ int kvm_set_msr_common(struct kvm_vcpu *vcpu, struct 
> msr_data *msr_info)
>   >requests);
>  
>   ka->boot_vcpu_runs_old_kvmclock = tmp;
> -
> - ka->kvmclock_offset = -get_kernel_ns();
>   }
>  
>   vcpu->arch.time = data;
> -- 
> 2.5.2

ACK

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[PATCH 2/2] Revert "KVM: x86: zero kvmclock_offset when vcpu0 initializes kvmclock system MSR"

2015-09-18 Thread Radim Krčmář 
Shifting pvclock_vcpu_time_info.system_time on write to KVM system time
MSR is a change of ABI.  Probably only 2.6.16 based SLES 10 breaks due
to its custom enhancements to kvmclock, but KVM never declared the MSR
only for one-shot initialization.  (Doc says that only one write is
needed.)

This reverts commit b7e60c5aedd2b63f16ef06fde4f81ca032211bc5.
And adds a note to the definition of PVCLOCK_COUNTS_FROM_ZERO.

Signed-off-by: Radim Krčmář 
---
 arch/x86/include/asm/pvclock-abi.h | 1 +
 arch/x86/kvm/x86.c | 4 
 2 files changed, 1 insertion(+), 4 deletions(-)

diff --git a/arch/x86/include/asm/pvclock-abi.h 
b/arch/x86/include/asm/pvclock-abi.h
index 655e07a48f6c..67f08230103a 100644
--- a/arch/x86/include/asm/pvclock-abi.h
+++ b/arch/x86/include/asm/pvclock-abi.h
@@ -41,6 +41,7 @@ struct pvclock_wall_clock {
 
 #define PVCLOCK_TSC_STABLE_BIT (1 << 0)
 #define PVCLOCK_GUEST_STOPPED  (1 << 1)
+/* PVCLOCK_COUNTS_FROM_ZERO broke ABI and can't be used anymore. */
 #define PVCLOCK_COUNTS_FROM_ZERO (1 << 2)
 #endif /* __ASSEMBLY__ */
 #endif /* _ASM_X86_PVCLOCK_ABI_H */
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 18d59b584dee..34d33f4757d2 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -1707,8 +1707,6 @@ static int kvm_guest_time_update(struct kvm_vcpu *v)
vcpu->pvclock_set_guest_stopped_request = false;
}
 
-   pvclock_flags |= PVCLOCK_COUNTS_FROM_ZERO;
-
/* If the host uses TSC clocksource, then it is stable */
if (use_master_clock)
pvclock_flags |= PVCLOCK_TSC_STABLE_BIT;
@@ -2006,8 +2004,6 @@ int kvm_set_msr_common(struct kvm_vcpu *vcpu, struct 
msr_data *msr_info)
>requests);
 
ka->boot_vcpu_runs_old_kvmclock = tmp;
-
-   ka->kvmclock_offset = -get_kernel_ns();
}
 
vcpu->arch.time = data;
-- 
2.5.2

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[PATCH 2/2] Revert "KVM: x86: zero kvmclock_offset when vcpu0 initializes kvmclock system MSR"

2015-09-18 Thread Radim Krčmář 
Shifting pvclock_vcpu_time_info.system_time on write to KVM system time
MSR is a change of ABI.  Probably only 2.6.16 based SLES 10 breaks due
to its custom enhancements to kvmclock, but KVM never declared the MSR
only for one-shot initialization.  (Doc says that only one write is
needed.)

This reverts commit b7e60c5aedd2b63f16ef06fde4f81ca032211bc5.
And adds a note to the definition of PVCLOCK_COUNTS_FROM_ZERO.

Signed-off-by: Radim Krčmář 
---
 arch/x86/include/asm/pvclock-abi.h | 1 +
 arch/x86/kvm/x86.c | 4 
 2 files changed, 1 insertion(+), 4 deletions(-)

diff --git a/arch/x86/include/asm/pvclock-abi.h 
b/arch/x86/include/asm/pvclock-abi.h
index 655e07a48f6c..67f08230103a 100644
--- a/arch/x86/include/asm/pvclock-abi.h
+++ b/arch/x86/include/asm/pvclock-abi.h
@@ -41,6 +41,7 @@ struct pvclock_wall_clock {
 
 #define PVCLOCK_TSC_STABLE_BIT (1 << 0)
 #define PVCLOCK_GUEST_STOPPED  (1 << 1)
+/* PVCLOCK_COUNTS_FROM_ZERO broke ABI and can't be used anymore. */
 #define PVCLOCK_COUNTS_FROM_ZERO (1 << 2)
 #endif /* __ASSEMBLY__ */
 #endif /* _ASM_X86_PVCLOCK_ABI_H */
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 18d59b584dee..34d33f4757d2 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -1707,8 +1707,6 @@ static int kvm_guest_time_update(struct kvm_vcpu *v)
vcpu->pvclock_set_guest_stopped_request = false;
}
 
-   pvclock_flags |= PVCLOCK_COUNTS_FROM_ZERO;
-
/* If the host uses TSC clocksource, then it is stable */
if (use_master_clock)
pvclock_flags |= PVCLOCK_TSC_STABLE_BIT;
@@ -2006,8 +2004,6 @@ int kvm_set_msr_common(struct kvm_vcpu *vcpu, struct 
msr_data *msr_info)
>requests);
 
ka->boot_vcpu_runs_old_kvmclock = tmp;
-
-   ka->kvmclock_offset = -get_kernel_ns();
}
 
vcpu->arch.time = data;
-- 
2.5.2

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