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Subject: Re: [PATCH v2 1/3] KVM: x86: implement KVM_{GET|SET}_TSC_STATE
To:     Marcelo Tosatti <mtosatti@redhat.com>,
        Thomas Gleixner <tglx@linutronix.de>
Cc:     Maxim Levitsky <mlevitsk@redhat.com>, kvm@vger.kernel.org,
        "H. Peter Anvin" <hpa@zytor.com>, Jonathan Corbet <corbet@lwn.net>,
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        Wanpeng Li <wanpengli@tencent.com>,
        "open list:KERNEL SELFTEST FRAMEWORK" 
        <linux-kselftest@vger.kernel.org>,
        Vitaly Kuznetsov <vkuznets@redhat.com>,
        Sean Christopherson <sean.j.christopherson@intel.com>,
        open list <linux-kernel@vger.kernel.org>,
        Ingo Molnar <mingo@redhat.com>,
        "maintainer:X86 ARCHITECTURE (32-BIT AND 64-BIT)" <x86@kernel.org>,
        Joerg Roedel <joro@8bytes.org>, Borislav Petkov <bp@alien8.de>,
        Shuah Khan <shuah@kernel.org>,
        Andrew Jones <drjones@redhat.com>,
        Oliver Upton <oupton@google.com>,
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From:   Paolo Bonzini <pbonzini@redhat.com>
Message-ID: <ec926c2c-985a-2e3d-1ba0-b35ce55a19c4@redhat.com>
Date:   Fri, 11 Dec 2020 14:37:27 +0100
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On 11/12/20 01:27, Marcelo Tosatti wrote:
> This features first, correctness later frenzy is insane and it better
> stops now before you pile even more crap on the existing steaming pile
> of insanities.

FWIW I agree, in fact I wish I knew exactly where to start simplifying 
it; the timekeeping code in KVM is perhaps the last remaining bastion 
where I'm afraid just to look at it.

At least I know there's a couple of features that IMHO are completely 
useless, and that's even before you reach the ones that might "only" be 
obsolete.  So perhaps that's where to start, together with the messiest 
userspace interfaces.

Paolo