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KVM: VMX: Add instruction rdtscp support for guest

PATCH In review Sheng Yang 2 participants 4 messages Dec 9, 2009 – Dec 10, 2009

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Sheng Yang

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#0 lore raw

PATCH 1/1 KVM: VMX: Add instruction rdtscp support for guest

Before enabling, execution of "rdtscp" in guest would result in #UD.

Signed-off-by Sheng Yang <[email protected]>
---
 arch/x86/include/asm/vmx.h |    1 +
 arch/x86/kvm/vmx.c         |    3 ++-
 2 files changed, 3 insertions(+), 1 deletions(-)
arch/x86/include/asm/vmx.h +1 -0
index 2b49454..8c39320 100644
@@ -53,6 +53,7 @@
  */
 #define SECONDARY_EXEC_VIRTUALIZE_APIC_ACCESSES 0x00000001
 #define SECONDARY_EXEC_ENABLE_EPT               0x00000002
+#define SECONDARY_EXEC_RDTSCP			0x00000008
 #define SECONDARY_EXEC_ENABLE_VPID              0x00000020
 #define SECONDARY_EXEC_WBINVD_EXITING		0x00000040
 #define SECONDARY_EXEC_UNRESTRICTED_GUEST	0x00000080
arch/x86/kvm/vmx.c +2 -1
index 9a0a2cf..e1a2ed2 100644
@@ -1243,7 +1243,8 @@ static __init int setup_vmcs_config(struct vmcs_config *vmcs_conf)
 			SECONDARY_EXEC_ENABLE_VPID |
 			SECONDARY_EXEC_ENABLE_EPT |
 			SECONDARY_EXEC_UNRESTRICTED_GUEST |
-			SECONDARY_EXEC_PAUSE_LOOP_EXITING;
+			SECONDARY_EXEC_PAUSE_LOOP_EXITING |
+			SECONDARY_EXEC_RDTSCP;
 		if (adjust_vmx_controls(min2, opt2,
 					MSR_IA32_VMX_PROCBASED_CTLS2,
 					&_cpu_based_2nd_exec_control) < 0)
Signature · 1 line
1.5.4.5
#1 lore raw
Quoted 26 lines · Sheng Yang

Before enabling, execution of "rdtscp" in guest would result in #UD.

Signed-off-by Sheng Yang<[email protected]>
---
  arch/x86/include/asm/vmx.h |    1 +
  arch/x86/kvm/vmx.c         |    3 ++-
  2 files changed, 3 insertions(+), 1 deletions(-)
arch/x86/include/asm/vmx.h +1 -0
index 2b49454..8c39320 100644
@@ -53,6 +53,7 @@
   */
  #define SECONDARY_EXEC_VIRTUALIZE_APIC_ACCESSES 0x00000001
  #define SECONDARY_EXEC_ENABLE_EPT               0x00000002
+#define SECONDARY_EXEC_RDTSCP			0x00000008
  #define SECONDARY_EXEC_ENABLE_VPID              0x00000020
  #define SECONDARY_EXEC_WBINVD_EXITING		0x00000040
  #define SECONDARY_EXEC_UNRESTRICTED_GUEST	0x00000080
arch/x86/kvm/vmx.c +0 -0
index 9a0a2cf..e1a2ed2 100644

arch/x86/kvm/vmx.c static __init int setup_vmcs_config(struct vmcs_config *vmcs_conf) · line 1250

Quoted 9 lines
arch/x86/kvm/vmx.c +2 -1
@@ -1243,7 +1243,8 @@ static __init int setup_vmcs_config(struct vmcs_config *vmcs_conf)
  			SECONDARY_EXEC_ENABLE_VPID |
  			SECONDARY_EXEC_ENABLE_EPT |
  			SECONDARY_EXEC_UNRESTRICTED_GUEST |
-			SECONDARY_EXEC_PAUSE_LOOP_EXITING;
+			SECONDARY_EXEC_PAUSE_LOOP_EXITING |
+			SECONDARY_EXEC_RDTSCP;
  		if (adjust_vmx_controls(min2, opt2,
  					MSR_IA32_VMX_PROCBASED_CTLS2,
  					&_cpu_based_2nd_exec_control)<  0)

Need to save/restore MSR_TSC_AUX (but only if rdtscp in cpuid), support MSR_TSC_AUX in get/save, and expose via GET_SUPPORTED_CPUID (only on processors which support the feature).

Signature · 1 line
Do not meddle in the internals of kernels, for they are subtle and quick to panic.
author
#2 lore raw
Quoted 31 lines · On Wednesday 09 December 2009 17:54:46 Avi Kivity wrote:
Quoted 30 lines · Sheng Yang

Before enabling, execution of "rdtscp" in guest would result in #UD.

Signed-off-by Sheng Yang<[email protected]>
---
  arch/x86/include/asm/vmx.h |    1 +
  arch/x86/kvm/vmx.c         |    3 ++-
  2 files changed, 3 insertions(+), 1 deletions(-)
arch/x86/include/asm/vmx.h +1 -0
index 2b49454..8c39320 100644
@@ -53,6 +53,7 @@
   */
  #define SECONDARY_EXEC_VIRTUALIZE_APIC_ACCESSES 0x00000001
  #define SECONDARY_EXEC_ENABLE_EPT               0x00000002
+#define SECONDARY_EXEC_RDTSCP			0x00000008
  #define SECONDARY_EXEC_ENABLE_VPID              0x00000020
  #define SECONDARY_EXEC_WBINVD_EXITING		0x00000040
  #define SECONDARY_EXEC_UNRESTRICTED_GUEST	0x00000080
arch/x86/kvm/vmx.c +0 -0
index 9a0a2cf..e1a2ed2 100644
@@ -1243,7 +1243,8 @@ static __init int setup_vmcs_config(struct

vmcs_config *vmcs_conf) SECONDARY_EXEC_ENABLE_VPID |
SECONDARY_EXEC_ENABLE_EPT | SECONDARY_EXEC_UNRESTRICTED_GUEST |

arch/x86/kvm/vmx.c +1 -1
-			SECONDARY_EXEC_PAUSE_LOOP_EXITING;
+			SECONDARY_EXEC_PAUSE_LOOP_EXITING |
Quoted 8 lines

arch/x86/kvm/vmx.c static __init int setup_vmcs_config(struct vmcs_config *vmcs_conf)

Quoted 4 lines
arch/x86/kvm/vmx.c +1 -0
+			SECONDARY_EXEC_RDTSCP;
  		if (adjust_vmx_controls(min2, opt2,
  					MSR_IA32_VMX_PROCBASED_CTLS2,
  					&_cpu_based_2nd_exec_control)<  0)

Need to save/restore MSR_TSC_AUX (but only if rdtscp in cpuid), support MSR_TSC_AUX in get/save, and expose via GET_SUPPORTED_CPUID (only on processors which support the feature).

Yeah, I realize this later last night... Though it passed my testing program.

Would update it soon.

Signature · 2 lines
regards
Yang, Sheng
#3 lore raw
Quoted 1 line · Sheng Yang

Yeah, I realize this later last night... Though it passed my testing program.

Please post the test program as well... it's now easy to extend kvm/user/test since it runs with qemu -kernel.

Signature · 1 line
error compiling committee.c: too many arguments to function