linux-kernel - Re: [PATCH] KVM: x86: Remove duplicated calls of reverse_cpuid

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Message-ID: <Y/TpLMRiNwGt2dhY@google.com>
Date:   Tue, 21 Feb 2023 07:54:20 -0800
From:   Sean Christopherson <seanjc@...gle.com>
To:     Binbin Wu <binbin.wu@...ux.intel.com>
Cc:     linux-kernel@...r.kernel.org, kvm@...r.kernel.org,
        pbonzini@...hat.com
Subject: Re: [PATCH] KVM: x86: Remove duplicated calls of reverse_cpuid_check()

On Tue, Feb 21, 2023, Binbin Wu wrote:
> Remove duplicated calls of reverse_cpuid_check() in __kvm_cpu_cap_mask()
> and kvm_cpu_cap_{clear, set, get}().

I want to keep the checks even though they are redundant.  There is no runtime
cost, and the intent of the direct calls in the "upper" helpers is as much to
document their usage constraints (input feature must be a compile-time constant)
as it is to enforce correctness.