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From:   Arnd Bergmann <arnd@kernel.org>
Date:   Thu, 29 Oct 2020 10:51:21 +0100
Message-ID: <CAK8P3a0e0YAkh_9S1ZG5FW3QozZnp1CwXUfWx9VHWkY=h+FVxw@mail.gmail.com>
Subject: Re: [PATCH] [v2] x86: apic: avoid -Wshadow warning in header
To:     Paolo Bonzini <pbonzini@redhat.com>
Cc:     Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        "the arch/x86 maintainers" <x86@kernel.org>,
        Arnd Bergmann <arnd@arndb.de>,
        "K. Y. Srinivasan" <kys@microsoft.com>,
        Haiyang Zhang <haiyangz@microsoft.com>,
        Stephen Hemminger <sthemmin@microsoft.com>,
        "H. Peter Anvin" <hpa@zytor.com>,
        "Rafael J. Wysocki" <rjw@rjwysocki.net>,
        Vitaly Kuznetsov <vkuznets@redhat.com>,
        Wanpeng Li <wanpengli@tencent.com>,
        Jim Mattson <jmattson@google.com>,
        Joerg Roedel <joro@8bytes.org>, linux-hyperv@vger.kernel.org,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        kvm list <kvm@vger.kernel.org>,
        Platform Driver <platform-driver-x86@vger.kernel.org>,
        xen-devel <xen-devel@lists.xenproject.org>,
        "open list:IOMMU DRIVERS" <iommu@lists.linux-foundation.org>
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On Thu, Oct 29, 2020 at 8:04 AM Paolo Bonzini <pbonzini@redhat.com> wrote:
>
> On 28/10/20 22:20, Arnd Bergmann wrote:
> > Avoid this by renaming the global 'apic' variable to the more descriptive
> > 'x86_system_apic'. It was originally called 'genapic', but both that
> > and the current 'apic' seem to be a little overly generic for a global
> > variable.
>
> The 'apic' affects only the current CPU, so one of 'x86_local_apic',
> 'x86_lapic' or 'x86_apic' is probably preferrable.

Ok, I'll change it to x86_local_apic then, unless someone else has
a preference between them.

> I don't have huge objections to renaming 'apic' variables and arguments
> in KVM to 'lapic'.  I do agree with Sean however that it's going to
> break again very soon.

I think ideally there would be no global variable, withall accesses
encapsulated in function calls, possibly using static_call() optimizations
if any of them are performance critical.

It doesn't seem hard to do, but I'd rather leave that change to
an x86 person ;-)

      Arnd