[PATCH v2 25/28] KVM: VMX: Store required-1 VMX controls in vmcs_config

From: Vitaly Kuznetsov
Date: Wed Jun 29 2022 - 11:09:01 EST


While constructing nested VMX MSRs values, nested_vmx_setup_ctls_msrs()
has to re-read host VMX control MSRs to get required-1 bits which are not
stored anywhre. Add this missing information to vmcs_config.

No functional change intended.

Signed-off-by: Vitaly Kuznetsov <vkuznets@xxxxxxxxxx>
---
arch/x86/kvm/vmx/capabilities.h | 5 +++++
arch/x86/kvm/vmx/vmx.c | 28 +++++++++++++++++++++-------
2 files changed, 26 insertions(+), 7 deletions(-)

diff --git a/arch/x86/kvm/vmx/capabilities.h b/arch/x86/kvm/vmx/capabilities.h
index 069d8d298e1d..2e223440e7ed 100644
--- a/arch/x86/kvm/vmx/capabilities.h
+++ b/arch/x86/kvm/vmx/capabilities.h
@@ -60,11 +60,16 @@ struct vmcs_config {
u32 basic_cap;
u32 revision_id;
u32 pin_based_exec_ctrl;
+ u32 pin_based_exec_ctrl_req1;
u32 cpu_based_exec_ctrl;
+ u32 cpu_based_exec_ctrl_req1;
u32 cpu_based_2nd_exec_ctrl;
+ u32 cpu_based_2nd_exec_ctrl_req1;
u64 cpu_based_3rd_exec_ctrl;
u32 vmexit_ctrl;
+ u32 vmexit_ctrl_req1;
u32 vmentry_ctrl;
+ u32 vmentry_ctrl_req1;
struct nested_vmx_msrs nested;
};
extern struct vmcs_config vmcs_config;
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 5d4158b7421c..c195c159738d 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -2442,7 +2442,7 @@ static bool cpu_has_perf_global_ctrl_bug(void)


static __init int adjust_vmx_controls(u32 ctl_min, u32 ctl_opt,
- u32 msr, u32 *result)
+ u32 msr, u32 *result_high, u32 *result_low)
{
u32 vmx_msr_low, vmx_msr_high;
u32 ctl = ctl_min | ctl_opt;
@@ -2456,7 +2456,8 @@ static __init int adjust_vmx_controls(u32 ctl_min, u32 ctl_opt,
if (ctl_min & ~ctl)
return -EIO;

- *result = ctl;
+ *result_high = ctl;
+ *result_low = vmx_msr_low;
return 0;
}

@@ -2479,6 +2480,11 @@ static __init int setup_vmcs_config(struct vmcs_config *vmcs_conf,
u64 _cpu_based_3rd_exec_control = 0;
u32 _vmexit_control = 0;
u32 _vmentry_control = 0;
+ u32 _pin_based_exec_control_low = 0;
+ u32 _cpu_based_exec_control_low = 0;
+ u32 _cpu_based_2nd_exec_control_low = 0;
+ u32 _vmexit_control_low = 0;
+ u32 _vmentry_control_low = 0;
int i;

/*
@@ -2502,13 +2508,15 @@ static __init int setup_vmcs_config(struct vmcs_config *vmcs_conf,
if (adjust_vmx_controls(KVM_REQ_VMX_CPU_BASED_VM_EXEC_CONTROL,
KVM_OPT_VMX_CPU_BASED_VM_EXEC_CONTROL,
MSR_IA32_VMX_PROCBASED_CTLS,
- &_cpu_based_exec_control) < 0)
+ &_cpu_based_exec_control,
+ &_cpu_based_exec_control_low) < 0)
return -EIO;
if (_cpu_based_exec_control & CPU_BASED_ACTIVATE_SECONDARY_CONTROLS) {
if (adjust_vmx_controls(KVM_REQ_VMX_SECONDARY_VM_EXEC_CONTROL,
KVM_OPT_VMX_SECONDARY_VM_EXEC_CONTROL,
MSR_IA32_VMX_PROCBASED_CTLS2,
- &_cpu_based_2nd_exec_control) < 0)
+ &_cpu_based_2nd_exec_control,
+ &_cpu_based_2nd_exec_control_low) < 0)
return -EIO;
}
#ifndef CONFIG_X86_64
@@ -2559,13 +2567,14 @@ static __init int setup_vmcs_config(struct vmcs_config *vmcs_conf,
if (adjust_vmx_controls(KVM_REQ_VMX_VM_EXIT_CONTROLS,
KVM_OPT_VMX_VM_EXIT_CONTROLS,
MSR_IA32_VMX_EXIT_CTLS,
- &_vmexit_control) < 0)
+ &_vmexit_control, &_vmexit_control_low) < 0)
return -EIO;

if (adjust_vmx_controls(KVM_REQ_VMX_PIN_BASED_VM_EXEC_CONTROL,
KVM_OPT_VMX_PIN_BASED_VM_EXEC_CONTROL,
MSR_IA32_VMX_PINBASED_CTLS,
- &_pin_based_exec_control) < 0)
+ &_pin_based_exec_control,
+ &_pin_based_exec_control_low) < 0)
return -EIO;

if (cpu_has_broken_vmx_preemption_timer())
@@ -2577,7 +2586,7 @@ static __init int setup_vmcs_config(struct vmcs_config *vmcs_conf,
if (adjust_vmx_controls(KVM_REQ_VMX_VM_ENTRY_CONTROLS,
KVM_OPT_VMX_VM_ENTRY_CONTROLS,
MSR_IA32_VMX_ENTRY_CTLS,
- &_vmentry_control) < 0)
+ &_vmentry_control, &_vmentry_control_low) < 0)
return -EIO;

for (i = 0; i < ARRAY_SIZE(vmcs_entry_exit_pairs); i++) {
@@ -2619,11 +2628,16 @@ static __init int setup_vmcs_config(struct vmcs_config *vmcs_conf,
vmcs_conf->revision_id = vmx_msr_low;

vmcs_conf->pin_based_exec_ctrl = _pin_based_exec_control;
+ vmcs_conf->pin_based_exec_ctrl_req1 = _pin_based_exec_control_low;
vmcs_conf->cpu_based_exec_ctrl = _cpu_based_exec_control;
+ vmcs_conf->cpu_based_exec_ctrl_req1 = _cpu_based_exec_control_low;
vmcs_conf->cpu_based_2nd_exec_ctrl = _cpu_based_2nd_exec_control;
+ vmcs_conf->cpu_based_2nd_exec_ctrl_req1 = _cpu_based_2nd_exec_control_low;
vmcs_conf->cpu_based_3rd_exec_ctrl = _cpu_based_3rd_exec_control;
vmcs_conf->vmexit_ctrl = _vmexit_control;
+ vmcs_conf->vmexit_ctrl_req1 = _vmexit_control_low;
vmcs_conf->vmentry_ctrl = _vmentry_control;
+ vmcs_conf->vmentry_ctrl_req1 = _vmentry_control_low;

return 0;
}
--
2.35.3