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KVM: nVMX: Use sanitized allowed-1 bits for VMX control MSRs

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Using raw host MSR values for setting up nested VMX control MSRs is
incorrect as some features need to disabled, e.g. when KVM runs as
a nested hypervisor on Hyper-V and uses Enlightened VMCS or when a
workaround for IA32_PERF_GLOBAL_CTRL is applied. For non-nested VMX, this
is done in setup_vmcs_config() and the result is stored in vmcs_config.
Use it for setting up allowed-1 bits in nested VMX MSRs too.

Suggested-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20220830133737.1539624-32-vkuznets@redhat.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Vitaly Kuznetsov 2022-08-30 15:37:35 +02:00 committed by Paolo Bonzini
parent 66a329be4b
commit bcdf201f8a
3 changed files with 15 additions and 22 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

30
arch/x86/kvm/vmx/nested.c
View File

@ -6568,8 +6568,10 @@ static u64 nested_vmx_calc_vmcs_enum_msr(void)
* bit in the high half is on if the corresponding bit in the control field
* may be on. See also vmx_control_verify().
*/
void nested_vmx_setup_ctls_msrs(struct nested_vmx_msrs *msrs, u32 ept_caps)
void nested_vmx_setup_ctls_msrs(struct vmcs_config *vmcs_conf, u32 ept_caps)
{
struct nested_vmx_msrs *msrs = &vmcs_conf->nested;
/*
* Note that as a general rule, the high half of the MSRs (bits in
* the control fields which may be 1) should be initialized by the
@ -6586,11 +6588,10 @@ void nested_vmx_setup_ctls_msrs(struct nested_vmx_msrs *msrs, u32 ept_caps)
*/
/* pin-based controls */
rdmsr(MSR_IA32_VMX_PINBASED_CTLS,
msrs->pinbased_ctls_low,
msrs->pinbased_ctls_high);
msrs->pinbased_ctls_low =
PIN_BASED_ALWAYSON_WITHOUT_TRUE_MSR;
msrs->pinbased_ctls_high = vmcs_conf->pin_based_exec_ctrl;
msrs->pinbased_ctls_high &=
PIN_BASED_EXT_INTR_MASK |
PIN_BASED_NMI_EXITING |
@ -6601,12 +6602,10 @@ void nested_vmx_setup_ctls_msrs(struct nested_vmx_msrs *msrs, u32 ept_caps)
PIN_BASED_VMX_PREEMPTION_TIMER;
/* exit controls */
rdmsr(MSR_IA32_VMX_EXIT_CTLS,
msrs->exit_ctls_low,
msrs->exit_ctls_high);
msrs->exit_ctls_low =
VM_EXIT_ALWAYSON_WITHOUT_TRUE_MSR;
msrs->exit_ctls_high = vmcs_conf->vmexit_ctrl;
msrs->exit_ctls_high &=
#ifdef CONFIG_X86_64
VM_EXIT_HOST_ADDR_SPACE_SIZE |
@ -6623,11 +6622,10 @@ void nested_vmx_setup_ctls_msrs(struct nested_vmx_msrs *msrs, u32 ept_caps)
msrs->exit_ctls_low &= ~VM_EXIT_SAVE_DEBUG_CONTROLS;
/* entry controls */
rdmsr(MSR_IA32_VMX_ENTRY_CTLS,
msrs->entry_ctls_low,
msrs->entry_ctls_high);
msrs->entry_ctls_low =
VM_ENTRY_ALWAYSON_WITHOUT_TRUE_MSR;
msrs->entry_ctls_high = vmcs_conf->vmentry_ctrl;
msrs->entry_ctls_high &=
#ifdef CONFIG_X86_64
VM_ENTRY_IA32E_MODE |
@ -6641,11 +6639,10 @@ void nested_vmx_setup_ctls_msrs(struct nested_vmx_msrs *msrs, u32 ept_caps)
msrs->entry_ctls_low &= ~VM_ENTRY_LOAD_DEBUG_CONTROLS;
/* cpu-based controls */
rdmsr(MSR_IA32_VMX_PROCBASED_CTLS,
msrs->procbased_ctls_low,
msrs->procbased_ctls_high);
msrs->procbased_ctls_low =
CPU_BASED_ALWAYSON_WITHOUT_TRUE_MSR;
msrs->procbased_ctls_high = vmcs_conf->cpu_based_exec_ctrl;
msrs->procbased_ctls_high &=
CPU_BASED_INTR_WINDOW_EXITING |
CPU_BASED_NMI_WINDOW_EXITING | CPU_BASED_USE_TSC_OFFSETTING |
@ -6679,12 +6676,9 @@ void nested_vmx_setup_ctls_msrs(struct nested_vmx_msrs *msrs, u32 ept_caps)
* depend on CPUID bits, they are added later by
* vmx_vcpu_after_set_cpuid.
*/
if (msrs->procbased_ctls_high & CPU_BASED_ACTIVATE_SECONDARY_CONTROLS)
rdmsr(MSR_IA32_VMX_PROCBASED_CTLS2,
msrs->secondary_ctls_low,
msrs->secondary_ctls_high);
msrs->secondary_ctls_low = 0;
msrs->secondary_ctls_high = vmcs_conf->cpu_based_2nd_exec_ctrl;
msrs->secondary_ctls_high &=
SECONDARY_EXEC_DESC |
SECONDARY_EXEC_ENABLE_RDTSCP |

2
arch/x86/kvm/vmx/nested.h
View File

@ -17,7 +17,7 @@ enum nvmx_vmentry_status {
};
void vmx_leave_nested(struct kvm_vcpu *vcpu);
void nested_vmx_setup_ctls_msrs(struct nested_vmx_msrs *msrs, u32 ept_caps);
void nested_vmx_setup_ctls_msrs(struct vmcs_config *vmcs_conf, u32 ept_caps);
void nested_vmx_hardware_unsetup(void);
__init int nested_vmx_hardware_setup(int (*exit_handlers[])(struct kvm_vcpu *));
void nested_vmx_set_vmcs_shadowing_bitmap(void);

5
arch/x86/kvm/vmx/vmx.c
View File

@ -7400,7 +7400,7 @@ static int __init vmx_check_processor_compat(void)
if (setup_vmcs_config(&vmcs_conf, &vmx_cap) < 0)
return -EIO;
if (nested)
nested_vmx_setup_ctls_msrs(&vmcs_conf.nested, vmx_cap.ept);
nested_vmx_setup_ctls_msrs(&vmcs_conf, vmx_cap.ept);
if (memcmp(&vmcs_config, &vmcs_conf, sizeof(struct vmcs_config)) != 0) {
printk(KERN_ERR "kvm: CPU %d feature inconsistency!\n",
smp_processor_id());
@ -8355,8 +8355,7 @@ static __init int hardware_setup(void)
setup_default_sgx_lepubkeyhash();
if (nested) {
nested_vmx_setup_ctls_msrs(&vmcs_config.nested,
vmx_capability.ept);
nested_vmx_setup_ctls_msrs(&vmcs_config, vmx_capability.ept);
r = nested_vmx_hardware_setup(kvm_vmx_exit_handlers);
if (r)