* [PATCH] KVM: nVMX: Add support for rdtscp
@ 2015-03-23 15:01 Jan Kiszka
2015-03-23 15:18 ` [PATCH v2] " Jan Kiszka
0 siblings, 1 reply; 7+ messages in thread
From: Jan Kiszka @ 2015-03-23 15:01 UTC (permalink / raw)
To: kvm, Marcelo Tosatti, Paolo Bonzini
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From: Jan Kiszka <jan.kiszka@siemens.com>
If the guest CPU is supposed to support rdtscp and the host has rdtscp
enabled in the secondary execution controls, we can also expose this
feature to L1. Just extend nested_vmx_exit_handled to properly route
EXIT_REASON_RDTSCP.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
---
arch/x86/include/uapi/asm/vmx.h | 1 +
arch/x86/kvm/vmx.c | 6 +++++-
2 files changed, 6 insertions(+), 1 deletion(-)
diff --git a/arch/x86/include/uapi/asm/vmx.h b/arch/x86/include/uapi/asm/vmx.h
index c5f1a1d..1fe9218 100644
--- a/arch/x86/include/uapi/asm/vmx.h
+++ b/arch/x86/include/uapi/asm/vmx.h
@@ -67,6 +67,7 @@
#define EXIT_REASON_EPT_VIOLATION 48
#define EXIT_REASON_EPT_MISCONFIG 49
#define EXIT_REASON_INVEPT 50
+#define EXIT_REASON_RDTSCP 51
#define EXIT_REASON_PREEMPTION_TIMER 52
#define EXIT_REASON_INVVPID 53
#define EXIT_REASON_WBINVD 54
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 50c675b..7875e9b 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -2467,6 +2467,7 @@ static void nested_vmx_setup_ctls_msrs(struct vcpu_vmx *vmx)
vmx->nested.nested_vmx_secondary_ctls_low = 0;
vmx->nested.nested_vmx_secondary_ctls_high &=
SECONDARY_EXEC_VIRTUALIZE_APIC_ACCESSES |
+ SECONDARY_EXEC_RDTSCP |
SECONDARY_EXEC_VIRTUALIZE_X2APIC_MODE |
SECONDARY_EXEC_APIC_REGISTER_VIRT |
SECONDARY_EXEC_VIRTUAL_INTR_DELIVERY |
@@ -7510,7 +7511,7 @@ static bool nested_vmx_exit_handled(struct kvm_vcpu *vcpu)
return nested_cpu_has(vmcs12, CPU_BASED_INVLPG_EXITING);
case EXIT_REASON_RDPMC:
return nested_cpu_has(vmcs12, CPU_BASED_RDPMC_EXITING);
- case EXIT_REASON_RDTSC:
+ case EXIT_REASON_RDTSC: case EXIT_REASON_RDTSCP:
return nested_cpu_has(vmcs12, CPU_BASED_RDTSC_EXITING);
case EXIT_REASON_VMCALL: case EXIT_REASON_VMCLEAR:
case EXIT_REASON_VMLAUNCH: case EXIT_REASON_VMPTRLD:
@@ -8517,6 +8518,9 @@ static void vmx_cpuid_update(struct kvm_vcpu *vcpu)
exec_control);
}
}
+ if (!vmx->rdtscp_enabled)
+ vmx->nested.nested_vmx_secondary_ctls_high &=
+ ~SECONDARY_EXEC_RDTSCP;
}
/* Exposing INVPCID only when PCID is exposed */
--
2.1.4
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^ permalink raw reply related [flat|nested] 7+ messages in thread
* [PATCH v2] KVM: nVMX: Add support for rdtscp
2015-03-23 15:01 [PATCH] KVM: nVMX: Add support for rdtscp Jan Kiszka
@ 2015-03-23 15:18 ` Jan Kiszka
2015-03-23 17:01 ` Bandan Das
0 siblings, 1 reply; 7+ messages in thread
From: Jan Kiszka @ 2015-03-23 15:18 UTC (permalink / raw)
To: kvm, Marcelo Tosatti, Paolo Bonzini
[-- Attachment #1: Type: text/plain, Size: 2982 bytes --]
From: Jan Kiszka <jan.kiszka@siemens.com>
If the guest CPU is supposed to support rdtscp and the host has rdtscp
enabled in the secondary execution controls, we can also expose this
feature to L1. Just extend nested_vmx_exit_handled to properly route
EXIT_REASON_RDTSCP.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
---
Changes in v2 (thinko in test scenario...):
- respect L1's setting of SECONDARY_EXEC_RDTSCP
arch/x86/include/uapi/asm/vmx.h | 1 +
arch/x86/kvm/vmx.c | 9 +++++++--
2 files changed, 8 insertions(+), 2 deletions(-)
diff --git a/arch/x86/include/uapi/asm/vmx.h b/arch/x86/include/uapi/asm/vmx.h
index c5f1a1d..1fe9218 100644
--- a/arch/x86/include/uapi/asm/vmx.h
+++ b/arch/x86/include/uapi/asm/vmx.h
@@ -67,6 +67,7 @@
#define EXIT_REASON_EPT_VIOLATION 48
#define EXIT_REASON_EPT_MISCONFIG 49
#define EXIT_REASON_INVEPT 50
+#define EXIT_REASON_RDTSCP 51
#define EXIT_REASON_PREEMPTION_TIMER 52
#define EXIT_REASON_INVVPID 53
#define EXIT_REASON_WBINVD 54
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 50c675b..45e0a6b 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -2467,6 +2467,7 @@ static void nested_vmx_setup_ctls_msrs(struct vcpu_vmx *vmx)
vmx->nested.nested_vmx_secondary_ctls_low = 0;
vmx->nested.nested_vmx_secondary_ctls_high &=
SECONDARY_EXEC_VIRTUALIZE_APIC_ACCESSES |
+ SECONDARY_EXEC_RDTSCP |
SECONDARY_EXEC_VIRTUALIZE_X2APIC_MODE |
SECONDARY_EXEC_APIC_REGISTER_VIRT |
SECONDARY_EXEC_VIRTUAL_INTR_DELIVERY |
@@ -7510,7 +7511,7 @@ static bool nested_vmx_exit_handled(struct kvm_vcpu *vcpu)
return nested_cpu_has(vmcs12, CPU_BASED_INVLPG_EXITING);
case EXIT_REASON_RDPMC:
return nested_cpu_has(vmcs12, CPU_BASED_RDPMC_EXITING);
- case EXIT_REASON_RDTSC:
+ case EXIT_REASON_RDTSC: case EXIT_REASON_RDTSCP:
return nested_cpu_has(vmcs12, CPU_BASED_RDTSC_EXITING);
case EXIT_REASON_VMCALL: case EXIT_REASON_VMCLEAR:
case EXIT_REASON_VMLAUNCH: case EXIT_REASON_VMPTRLD:
@@ -8517,6 +8518,9 @@ static void vmx_cpuid_update(struct kvm_vcpu *vcpu)
exec_control);
}
}
+ if (!vmx->rdtscp_enabled)
+ vmx->nested.nested_vmx_secondary_ctls_high &=
+ ~SECONDARY_EXEC_RDTSCP;
}
/* Exposing INVPCID only when PCID is exposed */
@@ -9146,8 +9150,9 @@ static void prepare_vmcs02(struct kvm_vcpu *vcpu, struct vmcs12 *vmcs12)
exec_control &= ~SECONDARY_EXEC_RDTSCP;
/* Take the following fields only from vmcs12 */
exec_control &= ~(SECONDARY_EXEC_VIRTUALIZE_APIC_ACCESSES |
+ SECONDARY_EXEC_RDTSCP |
SECONDARY_EXEC_VIRTUAL_INTR_DELIVERY |
- SECONDARY_EXEC_APIC_REGISTER_VIRT);
+ SECONDARY_EXEC_APIC_REGISTER_VIRT);
if (nested_cpu_has(vmcs12,
CPU_BASED_ACTIVATE_SECONDARY_CONTROLS))
exec_control |= vmcs12->secondary_vm_exec_control;
--
2.1.4
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^ permalink raw reply related [flat|nested] 7+ messages in thread
* Re: [PATCH v2] KVM: nVMX: Add support for rdtscp
2015-03-23 15:18 ` [PATCH v2] " Jan Kiszka
@ 2015-03-23 17:01 ` Bandan Das
2015-03-23 18:11 ` Jan Kiszka
0 siblings, 1 reply; 7+ messages in thread
From: Bandan Das @ 2015-03-23 17:01 UTC (permalink / raw)
To: Jan Kiszka; +Cc: kvm, Marcelo Tosatti, Paolo Bonzini
Jan Kiszka <jan.kiszka@web.de> writes:
...
> --- a/arch/x86/kvm/vmx.c
> +++ b/arch/x86/kvm/vmx.c
> @@ -2467,6 +2467,7 @@ static void nested_vmx_setup_ctls_msrs(struct vcpu_vmx *vmx)
> vmx->nested.nested_vmx_secondary_ctls_low = 0;
> vmx->nested.nested_vmx_secondary_ctls_high &=
> SECONDARY_EXEC_VIRTUALIZE_APIC_ACCESSES |
> + SECONDARY_EXEC_RDTSCP |
> SECONDARY_EXEC_VIRTUALIZE_X2APIC_MODE |
> SECONDARY_EXEC_APIC_REGISTER_VIRT |
> SECONDARY_EXEC_VIRTUAL_INTR_DELIVERY |
> @@ -7510,7 +7511,7 @@ static bool nested_vmx_exit_handled(struct kvm_vcpu *vcpu)
> return nested_cpu_has(vmcs12, CPU_BASED_INVLPG_EXITING);
> case EXIT_REASON_RDPMC:
> return nested_cpu_has(vmcs12, CPU_BASED_RDPMC_EXITING);
> - case EXIT_REASON_RDTSC:
> + case EXIT_REASON_RDTSC: case EXIT_REASON_RDTSCP:
> return nested_cpu_has(vmcs12, CPU_BASED_RDTSC_EXITING);
> case EXIT_REASON_VMCALL: case EXIT_REASON_VMCLEAR:
> case EXIT_REASON_VMLAUNCH: case EXIT_REASON_VMPTRLD:
> @@ -8517,6 +8518,9 @@ static void vmx_cpuid_update(struct kvm_vcpu *vcpu)
> exec_control);
> }
> }
> + if (!vmx->rdtscp_enabled)
> + vmx->nested.nested_vmx_secondary_ctls_high &=
> + ~SECONDARY_EXEC_RDTSCP;
No need to do this if nested is not enabled ? Or just
a "if (nested)" in the prior if else loop should be enough I think.
Bandan
> }
>
> /* Exposing INVPCID only when PCID is exposed */
> @@ -9146,8 +9150,9 @@ static void prepare_vmcs02(struct kvm_vcpu *vcpu, struct vmcs12 *vmcs12)
> exec_control &= ~SECONDARY_EXEC_RDTSCP;
> /* Take the following fields only from vmcs12 */
> exec_control &= ~(SECONDARY_EXEC_VIRTUALIZE_APIC_ACCESSES |
> + SECONDARY_EXEC_RDTSCP |
> SECONDARY_EXEC_VIRTUAL_INTR_DELIVERY |
> - SECONDARY_EXEC_APIC_REGISTER_VIRT);
> + SECONDARY_EXEC_APIC_REGISTER_VIRT);
> if (nested_cpu_has(vmcs12,
> CPU_BASED_ACTIVATE_SECONDARY_CONTROLS))
> exec_control |= vmcs12->secondary_vm_exec_control;
^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [PATCH v2] KVM: nVMX: Add support for rdtscp
2015-03-23 17:01 ` Bandan Das
@ 2015-03-23 18:11 ` Jan Kiszka
2015-03-23 18:18 ` Bandan Das
0 siblings, 1 reply; 7+ messages in thread
From: Jan Kiszka @ 2015-03-23 18:11 UTC (permalink / raw)
To: Bandan Das; +Cc: kvm, Marcelo Tosatti, Paolo Bonzini
[-- Attachment #1: Type: text/plain, Size: 1543 bytes --]
On 2015-03-23 18:01, Bandan Das wrote:
> Jan Kiszka <jan.kiszka@web.de> writes:
> ...
>> --- a/arch/x86/kvm/vmx.c
>> +++ b/arch/x86/kvm/vmx.c
>> @@ -2467,6 +2467,7 @@ static void nested_vmx_setup_ctls_msrs(struct vcpu_vmx *vmx)
>> vmx->nested.nested_vmx_secondary_ctls_low = 0;
>> vmx->nested.nested_vmx_secondary_ctls_high &=
>> SECONDARY_EXEC_VIRTUALIZE_APIC_ACCESSES |
>> + SECONDARY_EXEC_RDTSCP |
>> SECONDARY_EXEC_VIRTUALIZE_X2APIC_MODE |
>> SECONDARY_EXEC_APIC_REGISTER_VIRT |
>> SECONDARY_EXEC_VIRTUAL_INTR_DELIVERY |
>> @@ -7510,7 +7511,7 @@ static bool nested_vmx_exit_handled(struct kvm_vcpu *vcpu)
>> return nested_cpu_has(vmcs12, CPU_BASED_INVLPG_EXITING);
>> case EXIT_REASON_RDPMC:
>> return nested_cpu_has(vmcs12, CPU_BASED_RDPMC_EXITING);
>> - case EXIT_REASON_RDTSC:
>> + case EXIT_REASON_RDTSC: case EXIT_REASON_RDTSCP:
>> return nested_cpu_has(vmcs12, CPU_BASED_RDTSC_EXITING);
>> case EXIT_REASON_VMCALL: case EXIT_REASON_VMCLEAR:
>> case EXIT_REASON_VMLAUNCH: case EXIT_REASON_VMPTRLD:
>> @@ -8517,6 +8518,9 @@ static void vmx_cpuid_update(struct kvm_vcpu *vcpu)
>> exec_control);
>> }
>> }
>> + if (!vmx->rdtscp_enabled)
>> + vmx->nested.nested_vmx_secondary_ctls_high &=
>> + ~SECONDARY_EXEC_RDTSCP;
> No need to do this if nested is not enabled ? Or just
> a "if (nested)" in the prior if else loop should be enough I think.
I can add this - but this is far away from being a hotpath. What would
be the benefit?
Thanks,
Jan
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^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [PATCH v2] KVM: nVMX: Add support for rdtscp
2015-03-23 18:11 ` Jan Kiszka
@ 2015-03-23 18:18 ` Bandan Das
2015-03-23 18:27 ` [PATCH v3] " Jan Kiszka
0 siblings, 1 reply; 7+ messages in thread
From: Bandan Das @ 2015-03-23 18:18 UTC (permalink / raw)
To: Jan Kiszka; +Cc: kvm, Marcelo Tosatti, Paolo Bonzini
Jan Kiszka <jan.kiszka@web.de> writes:
> On 2015-03-23 18:01, Bandan Das wrote:
>> Jan Kiszka <jan.kiszka@web.de> writes:
>> ...
>>> --- a/arch/x86/kvm/vmx.c
>>> +++ b/arch/x86/kvm/vmx.c
>>> @@ -2467,6 +2467,7 @@ static void nested_vmx_setup_ctls_msrs(struct vcpu_vmx *vmx)
>>> vmx->nested.nested_vmx_secondary_ctls_low = 0;
>>> vmx->nested.nested_vmx_secondary_ctls_high &=
>>> SECONDARY_EXEC_VIRTUALIZE_APIC_ACCESSES |
>>> + SECONDARY_EXEC_RDTSCP |
>>> SECONDARY_EXEC_VIRTUALIZE_X2APIC_MODE |
>>> SECONDARY_EXEC_APIC_REGISTER_VIRT |
>>> SECONDARY_EXEC_VIRTUAL_INTR_DELIVERY |
>>> @@ -7510,7 +7511,7 @@ static bool nested_vmx_exit_handled(struct kvm_vcpu *vcpu)
>>> return nested_cpu_has(vmcs12, CPU_BASED_INVLPG_EXITING);
>>> case EXIT_REASON_RDPMC:
>>> return nested_cpu_has(vmcs12, CPU_BASED_RDPMC_EXITING);
>>> - case EXIT_REASON_RDTSC:
>>> + case EXIT_REASON_RDTSC: case EXIT_REASON_RDTSCP:
>>> return nested_cpu_has(vmcs12, CPU_BASED_RDTSC_EXITING);
>>> case EXIT_REASON_VMCALL: case EXIT_REASON_VMCLEAR:
>>> case EXIT_REASON_VMLAUNCH: case EXIT_REASON_VMPTRLD:
>>> @@ -8517,6 +8518,9 @@ static void vmx_cpuid_update(struct kvm_vcpu *vcpu)
>>> exec_control);
>>> }
>>> }
>>> + if (!vmx->rdtscp_enabled)
>>> + vmx->nested.nested_vmx_secondary_ctls_high &=
>>> + ~SECONDARY_EXEC_RDTSCP;
>> No need to do this if nested is not enabled ? Or just
>> a "if (nested)" in the prior if else loop should be enough I think.
>
> I can add this - but this is far away from being a hotpath. What would
> be the benefit?
Right, definitely not a hotpath, just seems unnecessary if nested is not enabled.
Bandan
> Thanks,
> Jan
^ permalink raw reply [flat|nested] 7+ messages in thread
* [PATCH v3] KVM: nVMX: Add support for rdtscp
2015-03-23 18:18 ` Bandan Das
@ 2015-03-23 18:27 ` Jan Kiszka
2015-03-27 1:34 ` Marcelo Tosatti
0 siblings, 1 reply; 7+ messages in thread
From: Jan Kiszka @ 2015-03-23 18:27 UTC (permalink / raw)
To: kvm, Marcelo Tosatti, Paolo Bonzini; +Cc: Bandan Das
[-- Attachment #1: Type: text/plain, Size: 2972 bytes --]
From: Jan Kiszka <jan.kiszka@siemens.com>
If the guest CPU is supposed to support rdtscp and the host has rdtscp
enabled in the secondary execution controls, we can also expose this
feature to L1. Just extend nested_vmx_exit_handled to properly route
EXIT_REASON_RDTSCP.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
---
Changes in v3:
- avoid needlessly touching vmx->nested if nested is off
arch/x86/include/uapi/asm/vmx.h | 1 +
arch/x86/kvm/vmx.c | 9 +++++++--
2 files changed, 8 insertions(+), 2 deletions(-)
diff --git a/arch/x86/include/uapi/asm/vmx.h b/arch/x86/include/uapi/asm/vmx.h
index c5f1a1d..1fe9218 100644
--- a/arch/x86/include/uapi/asm/vmx.h
+++ b/arch/x86/include/uapi/asm/vmx.h
@@ -67,6 +67,7 @@
#define EXIT_REASON_EPT_VIOLATION 48
#define EXIT_REASON_EPT_MISCONFIG 49
#define EXIT_REASON_INVEPT 50
+#define EXIT_REASON_RDTSCP 51
#define EXIT_REASON_PREEMPTION_TIMER 52
#define EXIT_REASON_INVVPID 53
#define EXIT_REASON_WBINVD 54
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 50c675b..fdd9f8b 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -2467,6 +2467,7 @@ static void nested_vmx_setup_ctls_msrs(struct vcpu_vmx *vmx)
vmx->nested.nested_vmx_secondary_ctls_low = 0;
vmx->nested.nested_vmx_secondary_ctls_high &=
SECONDARY_EXEC_VIRTUALIZE_APIC_ACCESSES |
+ SECONDARY_EXEC_RDTSCP |
SECONDARY_EXEC_VIRTUALIZE_X2APIC_MODE |
SECONDARY_EXEC_APIC_REGISTER_VIRT |
SECONDARY_EXEC_VIRTUAL_INTR_DELIVERY |
@@ -7510,7 +7511,7 @@ static bool nested_vmx_exit_handled(struct kvm_vcpu *vcpu)
return nested_cpu_has(vmcs12, CPU_BASED_INVLPG_EXITING);
case EXIT_REASON_RDPMC:
return nested_cpu_has(vmcs12, CPU_BASED_RDPMC_EXITING);
- case EXIT_REASON_RDTSC:
+ case EXIT_REASON_RDTSC: case EXIT_REASON_RDTSCP:
return nested_cpu_has(vmcs12, CPU_BASED_RDTSC_EXITING);
case EXIT_REASON_VMCALL: case EXIT_REASON_VMCLEAR:
case EXIT_REASON_VMLAUNCH: case EXIT_REASON_VMPTRLD:
@@ -8517,6 +8518,9 @@ static void vmx_cpuid_update(struct kvm_vcpu *vcpu)
exec_control);
}
}
+ if (nested && !vmx->rdtscp_enabled)
+ vmx->nested.nested_vmx_secondary_ctls_high &=
+ ~SECONDARY_EXEC_RDTSCP;
}
/* Exposing INVPCID only when PCID is exposed */
@@ -9146,8 +9150,9 @@ static void prepare_vmcs02(struct kvm_vcpu *vcpu, struct vmcs12 *vmcs12)
exec_control &= ~SECONDARY_EXEC_RDTSCP;
/* Take the following fields only from vmcs12 */
exec_control &= ~(SECONDARY_EXEC_VIRTUALIZE_APIC_ACCESSES |
+ SECONDARY_EXEC_RDTSCP |
SECONDARY_EXEC_VIRTUAL_INTR_DELIVERY |
- SECONDARY_EXEC_APIC_REGISTER_VIRT);
+ SECONDARY_EXEC_APIC_REGISTER_VIRT);
if (nested_cpu_has(vmcs12,
CPU_BASED_ACTIVATE_SECONDARY_CONTROLS))
exec_control |= vmcs12->secondary_vm_exec_control;
--
2.1.4
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^ permalink raw reply related [flat|nested] 7+ messages in thread
* Re: [PATCH v3] KVM: nVMX: Add support for rdtscp
2015-03-23 18:27 ` [PATCH v3] " Jan Kiszka
@ 2015-03-27 1:34 ` Marcelo Tosatti
0 siblings, 0 replies; 7+ messages in thread
From: Marcelo Tosatti @ 2015-03-27 1:34 UTC (permalink / raw)
To: Jan Kiszka; +Cc: kvm, Paolo Bonzini, Bandan Das
On Mon, Mar 23, 2015 at 07:27:19PM +0100, Jan Kiszka wrote:
> From: Jan Kiszka <jan.kiszka@siemens.com>
>
> If the guest CPU is supposed to support rdtscp and the host has rdtscp
> enabled in the secondary execution controls, we can also expose this
> feature to L1. Just extend nested_vmx_exit_handled to properly route
> EXIT_REASON_RDTSCP.
>
> Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Applied, thanks.
^ permalink raw reply [flat|nested] 7+ messages in thread
end of thread, other threads:[~2015-03-27 1:34 UTC | newest]
Thread overview: 7+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2015-03-23 15:01 [PATCH] KVM: nVMX: Add support for rdtscp Jan Kiszka
2015-03-23 15:18 ` [PATCH v2] " Jan Kiszka
2015-03-23 17:01 ` Bandan Das
2015-03-23 18:11 ` Jan Kiszka
2015-03-23 18:18 ` Bandan Das
2015-03-23 18:27 ` [PATCH v3] " Jan Kiszka
2015-03-27 1:34 ` Marcelo Tosatti
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