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([2001:b07:6468:f312:c8dd:75d4:99ab:290a]) by smtp.gmail.com with ESMTPSA id z64sm13966730wme.10.2020.12.11.05.37.28 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 11 Dec 2020 05:37:28 -0800 (PST) Subject: Re: [PATCH v2 1/3] KVM: x86: implement KVM_{GET|SET}_TSC_STATE To: Marcelo Tosatti , Thomas Gleixner Cc: Maxim Levitsky , kvm@vger.kernel.org, "H. Peter Anvin" , Jonathan Corbet , Jim Mattson , Wanpeng Li , "open list:KERNEL SELFTEST FRAMEWORK" , Vitaly Kuznetsov , Sean Christopherson , open list , Ingo Molnar , "maintainer:X86 ARCHITECTURE (32-BIT AND 64-BIT)" , Joerg Roedel , Borislav Petkov , Shuah Khan , Andrew Jones , Oliver Upton , "open list:DOCUMENTATION" References: <20201203171118.372391-2-mlevitsk@redhat.com> <20201207232920.GD27492@fuller.cnet> <05aaabedd4aac7d3bce81d338988108885a19d29.camel@redhat.com> <87sg8g2sn4.fsf@nanos.tec.linutronix.de> <20201208181107.GA31442@fuller.cnet> <875z5c2db8.fsf@nanos.tec.linutronix.de> <20201209163434.GA22851@fuller.cnet> <87r1nyzogg.fsf@nanos.tec.linutronix.de> <20201210152618.GB23951@fuller.cnet> <87zh2lib8l.fsf@nanos.tec.linutronix.de> <20201211002703.GA47016@fuller.cnet> From: Paolo Bonzini Message-ID: Date: Fri, 11 Dec 2020 14:37:27 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.4.0 MIME-Version: 1.0 In-Reply-To: <20201211002703.GA47016@fuller.cnet> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-doc@vger.kernel.org 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