From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id F2333C0018C for ; Fri, 11 Dec 2020 00:05:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C8A0B23EB1 for ; Fri, 11 Dec 2020 00:05:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2390339AbgLKAFM (ORCPT ); Thu, 10 Dec 2020 19:05:12 -0500 Received: from Galois.linutronix.de ([193.142.43.55]:59118 "EHLO galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2389478AbgLKAEd (ORCPT ); Thu, 10 Dec 2020 19:04:33 -0500 From: Thomas Gleixner DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1607645028; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=gKnbSWvo8xgTWID+gjefEKKndhjtzYov0drs0ofkV50=; b=UgL/pVRQVx6CwCqI/WGkF/Mp3fuDuGQXlfnEMqs9tAdeD1zA2jL+UNbySvoyUOUhqj391I dvrrru3OXdKZbXN8hnFkG/lPNvuMpVNPmyIC9MRWshE0EmeTJzHmoVLJa4FbStrMSsmRBY TJhUbXPHpTpFRcIBA87MGLlFhyqAYyV65PgpjefcWWAmHsFW8/Ub8FkbYBSI0p4GGfJZsC S/B+8VX1osg6+PJ9KI5x6jCHclWqt8nh6LQIlDnsrImlfUxqItyIiRwsPy0OlBZvQu39jE 9oE/SbkSpKNaiR3oNTwdCQki9hEtB3XrWLgo6gJen0fob30LKEx75cVogkz70A== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1607645028; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=gKnbSWvo8xgTWID+gjefEKKndhjtzYov0drs0ofkV50=; b=hrZAtY96p4hQAVs/6ikH5XoTRunFp/9Y1K0KGacfOMgUsJ3TCVL0dXSGKVDsS8n56160U7 a0S0FM1PUR58cVCA== To: Andy Lutomirski Cc: Andy Lutomirski , Maxim Levitsky , Paolo Bonzini , Marcelo Tosatti , kvm list , "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" Subject: Re: [PATCH v2 1/3] KVM: x86: implement KVM_{GET|SET}_TSC_STATE In-Reply-To: References: <87v9d9i9dt.fsf@nanos.tec.linutronix.de> Date: Fri, 11 Dec 2020 01:03:47 +0100 Message-ID: <87lfe5i4yk.fsf@nanos.tec.linutronix.de> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Dec 10 2020 at 15:19, Andy Lutomirski wrote: >> On Dec 10, 2020, at 2:28 PM, Thomas Gleixner wrote: >> Can we please focus on real problems instead of making up new ones? >>=20 >> Correctness of time is a real problem despite the believe of virt folks >> that it can be ignored or duct taped to death. >>=20 > I=E2=80=99m fine with this as long as it=E2=80=99s intentional. If we say= =E2=80=9Cguest > timekeeping across host suspend is correct because we notify the > guest=E2=80=9D, then we have a hole. But if we say =E2=80=9Cthe host will= try to > notify the guest, and if the guest is out to lunch then the host > reserves the right to suspend without waiting, and the guest should > deal with this=E2=80=9D, then okay. Yes of course this would be intentional and documented behaviour, which is an infinite improvement over the current situation. Thanks, tglx