linux-kernel - Re: [PATCH 18/61] KVM: x86: Use common loop iterator when handling CPUID 0xD.N

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Date:   Fri, 21 Feb 2020 16:04:54 +0100
From:   Vitaly Kuznetsov <vkuznets@...hat.com>
To:     Sean Christopherson <sean.j.christopherson@...el.com>
Cc:     Paolo Bonzini <pbonzini@...hat.com>,
        Wanpeng Li <wanpengli@...cent.com>,
        Jim Mattson <jmattson@...gle.com>,
        Joerg Roedel <joro@...tes.org>, kvm@...r.kernel.org,
        linux-kernel@...r.kernel.org
Subject: Re: [PATCH 18/61] KVM: x86: Use common loop iterator when handling CPUID 0xD.N

Sean Christopherson <sean.j.christopherson@...el.com> writes:

> Use __do_cpuid_func()'s common loop iterator, "i", when enumerating the
> sub-leafs for CPUID 0xD now that the CPUID 0xD loop doesn't need to
> manual maintain separate counts for the entries index and CPUID index.
>
> No functional changed intended.
>
> Signed-off-by: Sean Christopherson <sean.j.christopherson@...el.com>
> ---
>  arch/x86/kvm/cpuid.c | 7 +++----
>  1 file changed, 3 insertions(+), 4 deletions(-)
>
> diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
> index 6516fec361c1..bfd8304a8437 100644
> --- a/arch/x86/kvm/cpuid.c
> +++ b/arch/x86/kvm/cpuid.c
> @@ -634,7 +634,6 @@ static inline int __do_cpuid_func(struct kvm_cpuid_array *array, u32 function)
>  		}
>  		break;
>  	case 0xd: {
> -		int idx;
>  		u64 supported = kvm_supported_xcr0();
>  
>  		entry->eax &= supported;
> @@ -658,11 +657,11 @@ static inline int __do_cpuid_func(struct kvm_cpuid_array *array, u32 function)
>  		entry->ecx = 0;
>  		entry->edx = 0;
>  
> -		for (idx = 2; idx < 64; ++idx) {
> -			if (!(supported & BIT_ULL(idx)))
> +		for (i = 2; i < 64; ++i) {
> +			if (!(supported & BIT_ULL(i)))
>  				continue;
>  
> -			entry = do_host_cpuid(array, function, idx);
> +			entry = do_host_cpuid(array, function, i);
>  			if (!entry)
>  				goto out;

Reviewed-by: Vitaly Kuznetsov <vkuznets@...hat.com>

-- 
Vitaly