[PATCH] target/i386: Raise the highest index value used for any VMCS encoding

[PATCH] target/i386: Raise the highest index value used for any VMCS encoding

[Lei Wang]

Because the index value of the VMCS field encoding of Secondary VM-exit
controls, 0x44, is larger than any existing index value, raise the highest
index value used for any VMCS encoding to 0x44.

Because the index value of the VMCS field encoding of FRED injected-event
data (one of the newly added VMCS fields for FRED transitions), 0x52, is
larger than any existing index value, raise the highest index value used
for any VMCS encoding to 0x52.

Co-developed-by: Xin Li <xin3.li@intel.com>
Signed-off-by: Xin Li <xin3.li@intel.com>
Signed-off-by: Lei Wang <lei4.wang@intel.com>
---
 target/i386/cpu.h     | 1 +
 target/i386/kvm/kvm.c | 9 ++++++++-
 2 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/target/i386/cpu.h b/target/i386/cpu.h
index c6cc035df3..5604cc2994 100644
--- a/target/i386/cpu.h
+++ b/target/i386/cpu.h
@@ -1192,6 +1192,7 @@ uint64_t x86_cpu_get_supported_feature_word(X86CPU *cpu, FeatureWord w);
 #define VMX_VM_EXIT_PT_CONCEAL_PIP                  0x01000000
 #define VMX_VM_EXIT_CLEAR_IA32_RTIT_CTL             0x02000000
 #define VMX_VM_EXIT_LOAD_IA32_PKRS                  0x20000000
+#define VMX_VM_EXIT_ACTIVATE_SECONDARY_CONTROLS     0x80000000
 
 #define VMX_VM_ENTRY_LOAD_DEBUG_CONTROLS            0x00000004
 #define VMX_VM_ENTRY_IA32E_MODE                     0x00000200
diff --git a/target/i386/kvm/kvm.c b/target/i386/kvm/kvm.c
index b4aab9a410..7c8cb16675 100644
--- a/target/i386/kvm/kvm.c
+++ b/target/i386/kvm/kvm.c
@@ -3694,7 +3694,14 @@ static void kvm_msr_entry_add_vmx(X86CPU *cpu, FeatureWordArray f)
     kvm_msr_entry_add(cpu, MSR_IA32_VMX_CR4_FIXED0,
                       CR4_VMXE_MASK);
 
-    if (f[FEAT_VMX_SECONDARY_CTLS] & VMX_SECONDARY_EXEC_TSC_SCALING) {
+    if (f[FEAT_7_1_EAX] & CPUID_7_1_EAX_FRED) {
+        /* FRED injected-event data (0x2052).  */
+        kvm_msr_entry_add(cpu, MSR_IA32_VMX_VMCS_ENUM, 0x52);
+    } else if (f[FEAT_VMX_EXIT_CTLS] &
+               VMX_VM_EXIT_ACTIVATE_SECONDARY_CONTROLS) {
+        /* Secondary VM-exit controls (0x2044).  */
+        kvm_msr_entry_add(cpu, MSR_IA32_VMX_VMCS_ENUM, 0x44);
+    } else if (f[FEAT_VMX_SECONDARY_CTLS] & VMX_SECONDARY_EXEC_TSC_SCALING) {
         /* TSC multiplier (0x2032).  */
         kvm_msr_entry_add(cpu, MSR_IA32_VMX_VMCS_ENUM, 0x32);
     } else {
-- 
2.39.3

Re: [PATCH] target/i386: Raise the highest index value used for any VMCS encoding

[Paolo Bonzini]

On Wed, Jul 24, 2024 at 10:09 AM Lei Wang <lei4.wang@intel.com> wrote:
> Because the index value of the VMCS field encoding of Secondary VM-exit
> controls, 0x44, is larger than any existing index value, raise the highest
> index value used for any VMCS encoding to 0x44.
>
> Because the index value of the VMCS field encoding of FRED injected-event
> data (one of the newly added VMCS fields for FRED transitions), 0x52, is
> larger than any existing index value, raise the highest index value used
> for any VMCS encoding to 0x52.

Hi, can you put together a complete series that includes all that's
needed for nested FRED support?

Thanks,

Paolo

> Co-developed-by: Xin Li <xin3.li@intel.com>
> Signed-off-by: Xin Li <xin3.li@intel.com>
> Signed-off-by: Lei Wang <lei4.wang@intel.com>
> ---
>  target/i386/cpu.h     | 1 +
>  target/i386/kvm/kvm.c | 9 ++++++++-
>  2 files changed, 9 insertions(+), 1 deletion(-)
>
> diff --git a/target/i386/cpu.h b/target/i386/cpu.h
> index c6cc035df3..5604cc2994 100644
> --- a/target/i386/cpu.h
> +++ b/target/i386/cpu.h
> @@ -1192,6 +1192,7 @@ uint64_t x86_cpu_get_supported_feature_word(X86CPU *cpu, FeatureWord w);
>  #define VMX_VM_EXIT_PT_CONCEAL_PIP                  0x01000000
>  #define VMX_VM_EXIT_CLEAR_IA32_RTIT_CTL             0x02000000
>  #define VMX_VM_EXIT_LOAD_IA32_PKRS                  0x20000000
> +#define VMX_VM_EXIT_ACTIVATE_SECONDARY_CONTROLS     0x80000000
>
>  #define VMX_VM_ENTRY_LOAD_DEBUG_CONTROLS            0x00000004
>  #define VMX_VM_ENTRY_IA32E_MODE                     0x00000200
> diff --git a/target/i386/kvm/kvm.c b/target/i386/kvm/kvm.c
> index b4aab9a410..7c8cb16675 100644
> --- a/target/i386/kvm/kvm.c
> +++ b/target/i386/kvm/kvm.c
> @@ -3694,7 +3694,14 @@ static void kvm_msr_entry_add_vmx(X86CPU *cpu, FeatureWordArray f)
>      kvm_msr_entry_add(cpu, MSR_IA32_VMX_CR4_FIXED0,
>                        CR4_VMXE_MASK);
>
> -    if (f[FEAT_VMX_SECONDARY_CTLS] & VMX_SECONDARY_EXEC_TSC_SCALING) {
> +    if (f[FEAT_7_1_EAX] & CPUID_7_1_EAX_FRED) {
> +        /* FRED injected-event data (0x2052).  */
> +        kvm_msr_entry_add(cpu, MSR_IA32_VMX_VMCS_ENUM, 0x52);
> +    } else if (f[FEAT_VMX_EXIT_CTLS] &
> +               VMX_VM_EXIT_ACTIVATE_SECONDARY_CONTROLS) {
> +        /* Secondary VM-exit controls (0x2044).  */
> +        kvm_msr_entry_add(cpu, MSR_IA32_VMX_VMCS_ENUM, 0x44);
> +    } else if (f[FEAT_VMX_SECONDARY_CTLS] & VMX_SECONDARY_EXEC_TSC_SCALING) {
>          /* TSC multiplier (0x2032).  */
>          kvm_msr_entry_add(cpu, MSR_IA32_VMX_VMCS_ENUM, 0x32);
>      } else {
> --
> 2.39.3
>

RE: [PATCH] target/i386: Raise the highest index value used for any VMCS encoding

[Li, Xin3]

> On Wed, Jul 24, 2024 at 10:09 AM Lei Wang <lei4.wang@intel.com> wrote:
> > Because the index value of the VMCS field encoding of Secondary
> > VM-exit controls, 0x44, is larger than any existing index value, raise
> > the highest index value used for any VMCS encoding to 0x44.
> >
> > Because the index value of the VMCS field encoding of FRED
> > injected-event data (one of the newly added VMCS fields for FRED
> > transitions), 0x52, is larger than any existing index value, raise the
> > highest index value used for any VMCS encoding to 0x52.
> 
> Hi, can you put together a complete series that includes all that's needed for
> nested FRED support?
> 

We can do it.

Just to be clear, this patch is not needed to enable nested FRED, but to
fix the following vmx test in kvm-unit-tests, otherwise we get:
    FAIL: VMX_VMCS_ENUM.MAX_INDEX expected: 29, actual: 19

Thanks!
    Xin

Re: [PATCH] target/i386: Raise the highest index value used for any VMCS encoding

[Paolo Bonzini]

On Fri, Jul 26, 2024 at 3:12 AM Li, Xin3 <xin3.li@intel.com> wrote:
> > Hi, can you put together a complete series that includes all that's needed for
> > nested FRED support?
>
> We can do it.
>
> Just to be clear, this patch is not needed to enable nested FRED, but to
> fix the following vmx test in kvm-unit-tests, otherwise we get:
>     FAIL: VMX_VMCS_ENUM.MAX_INDEX expected: 29, actual: 19

But neither bit is defined without nested FRED (and failures if you
use -cpu host,migratable=no are expected).

Paolo