No need to use MAX_POSSIBLE_PASSTHROUGH_MSRS in the definition of array vmx_possible_passthrough_msrs, as the macro name indicates the _possible_ maximum size of passthrough MSRs. Use ARRAY_SIZE instead of MAX_POSSIBLE_PASSTHROUGH_MSRS when the size of the array is needed and add a BUILD_BUG_ON to make sure the actual array size does not exceed the possible maximum size of passthrough MSRs. Signed-off-by: Xin Li (Intel) <xin@xxxxxxxxx> Tested-by: Shan Kang <shan.kang@xxxxxxxxx> --- arch/x86/kvm/vmx/vmx.c | 8 +++++--- arch/x86/kvm/vmx/vmx.h | 2 +- 2 files changed, 6 insertions(+), 4 deletions(-) diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index 9acc9661fdb2..28cf89c97bda 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -167,7 +167,7 @@ module_param(allow_smaller_maxphyaddr, bool, S_IRUGO); * List of MSRs that can be directly passed to the guest. * In addition to these x2apic, PT and LBR MSRs are handled specially. */ -static u32 vmx_possible_passthrough_msrs[MAX_POSSIBLE_PASSTHROUGH_MSRS] = { +static u32 vmx_possible_passthrough_msrs[] = { MSR_IA32_SPEC_CTRL, MSR_IA32_PRED_CMD, MSR_IA32_FLUSH_CMD, @@ -4182,6 +4182,8 @@ void vmx_msr_filter_changed(struct kvm_vcpu *vcpu) if (!cpu_has_vmx_msr_bitmap()) return; + BUILD_BUG_ON(ARRAY_SIZE(vmx_possible_passthrough_msrs) > MAX_POSSIBLE_PASSTHROUGH_MSRS); + /* * Redo intercept permissions for MSRs that KVM is passing through to * the guest. Disabling interception will check the new MSR filter and @@ -7626,8 +7628,8 @@ int vmx_vcpu_create(struct kvm_vcpu *vcpu) } /* The MSR bitmap starts with all ones */ - bitmap_fill(vmx->shadow_msr_intercept.read, MAX_POSSIBLE_PASSTHROUGH_MSRS); - bitmap_fill(vmx->shadow_msr_intercept.write, MAX_POSSIBLE_PASSTHROUGH_MSRS); + bitmap_fill(vmx->shadow_msr_intercept.read, ARRAY_SIZE(vmx_possible_passthrough_msrs)); + bitmap_fill(vmx->shadow_msr_intercept.write, ARRAY_SIZE(vmx_possible_passthrough_msrs)); vmx_disable_intercept_for_msr(vcpu, MSR_IA32_TSC, MSR_TYPE_R); #ifdef CONFIG_X86_64 diff --git a/arch/x86/kvm/vmx/vmx.h b/arch/x86/kvm/vmx/vmx.h index e0d76d2460ef..e7409f8f28b1 100644 --- a/arch/x86/kvm/vmx/vmx.h +++ b/arch/x86/kvm/vmx/vmx.h @@ -356,7 +356,7 @@ struct vcpu_vmx { struct lbr_desc lbr_desc; /* Save desired MSR intercept (read: pass-through) state */ -#define MAX_POSSIBLE_PASSTHROUGH_MSRS 16 +#define MAX_POSSIBLE_PASSTHROUGH_MSRS 64 struct { DECLARE_BITMAP(read, MAX_POSSIBLE_PASSTHROUGH_MSRS); DECLARE_BITMAP(write, MAX_POSSIBLE_PASSTHROUGH_MSRS); -- 2.46.2