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=-0.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS 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 2E81CC43331 for ; Wed, 25 Mar 2020 14:28:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 052DE208E4 for ; Wed, 25 Mar 2020 14:28:55 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="eCJzh0B+" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727729AbgCYO2y (ORCPT ); Wed, 25 Mar 2020 10:28:54 -0400 Received: from us-smtp-delivery-74.mimecast.com ([216.205.24.74]:41916 "EHLO us-smtp-delivery-74.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727566AbgCYO2x (ORCPT ); Wed, 25 Mar 2020 10:28:53 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1585146532; 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: in-reply-to:in-reply-to:references:references; bh=JqpwltFL/SwS1UhlcIi0MOoODF8Cpbq1cMt7ik4CiTE=; b=eCJzh0B+mr7vKWlmwWwcLSOEXGOTZJf9mYzK6cdKHKCllG4l9Ec4FaU3u60DDtJfszD+41 SJn7MzXpw6J+olXnt1sxu0qY8yueTRGm709MPfBNyPsq/ZZ2mDEGJ7eLkvU8eQN53zsTKL /rOuwAH/HsStfKcvSLAAn4HMy8eOaCo= Received: from mail-wm1-f72.google.com (mail-wm1-f72.google.com [209.85.128.72]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-61-Xh-tGqPVPomG34DhCv4tFA-1; Wed, 25 Mar 2020 10:28:49 -0400 X-MC-Unique: Xh-tGqPVPomG34DhCv4tFA-1 Received: by mail-wm1-f72.google.com with SMTP id m4so949449wmi.5 for ; Wed, 25 Mar 2020 07:28:48 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:in-reply-to:references:date :message-id:mime-version; bh=JqpwltFL/SwS1UhlcIi0MOoODF8Cpbq1cMt7ik4CiTE=; b=nIUCL8d7n94+/6fC5aaHSyIYjqKQdiviEWqSbGXg2xAOiuIPbhrd52zQolk7sUXY7Z 6lLfut2q9wooN5n0MJmdNxGwBwrtV7K1BgZ52pUeE0Sk5rO138EQsiESOlyI2tPMOl27 W7+G+XIl9+eGzNt57YxpA3uaiBn4PBsTlVwknyGTqZu3W1c67RBijkazHEzOL219MLvI A/BiWLHaH6ORnvunyJ0Vgqhmpm9nFqBbxxMGYWbDnaPD5CLPiHxKmgcHHC8zNcF2vW04 +wTsjJNfrfuN4CTvxN8NwEvpIgSQfVplGGe3HcnTrTWgl03TvxYvhcJjdCPfCujePfqB U+sA== X-Gm-Message-State: ANhLgQ0WC4n3MyHFi1P7MK/JtONiFpHMgAq4hBEtWdIrq8pincm64PYZ kv2WOGY6WSMcXpxZ6ymnV+uzTbsqhbjIr+2T47RhzcfX9NiOp6uVfs6TRqNUMC76MjMoEacGgrf 2AzrOglQUiCTKb9mZ X-Received: by 2002:a7b:c050:: with SMTP id u16mr4024617wmc.68.1585146527996; Wed, 25 Mar 2020 07:28:47 -0700 (PDT) X-Google-Smtp-Source: ADFU+vtps1lqlEjeVqhmoxqx06a7QnIYlVTNWJazZkk/ssQW3dTzHNkG7M+s2wksPvvsb7XCMHkt2A== X-Received: by 2002:a7b:c050:: with SMTP id u16mr4024590wmc.68.1585146527811; Wed, 25 Mar 2020 07:28:47 -0700 (PDT) Received: from vitty.brq.redhat.com (g-server-2.ign.cz. [91.219.240.2]) by smtp.gmail.com with ESMTPSA id v7sm9590018wml.18.2020.03.25.07.28.46 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 25 Mar 2020 07:28:47 -0700 (PDT) From: Vitaly Kuznetsov To: Tianyu Lan Cc: Yubo Xie , linux-hyperv@vger.kernel.org, linux-kernel@vger.kernel.org, stable@vger.kernel.org, Tianyu Lan , kys@microsoft.com, haiyangz@microsoft.com, sthemmin@microsoft.com, liuwe@microsoft.com, daniel.lezcano@linaro.org, tglx@linutronix.de, michael.h.kelley@microsoft.com Subject: Re: [PATCH] x86/Hyper-V: Fix hv sched clock function return wrong time unit In-Reply-To: <039e126f-f00d-d7e1-aa92-c049c9e3333b@gmail.com> References: <20200324151935.15814-1-yuboxie@microsoft.com> <87ftdx7nxv.fsf@vitty.brq.redhat.com> <039e126f-f00d-d7e1-aa92-c049c9e3333b@gmail.com> Date: Wed, 25 Mar 2020 15:28:45 +0100 Message-ID: <87lfno5x0i.fsf@vitty.brq.redhat.com> MIME-Version: 1.0 Content-Type: text/plain Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org Tianyu Lan writes: >>> @@ -398,7 +399,8 @@ static u64 notrace read_hv_clock_msr_cs(struct clocksource *arg) >>> >>> static u64 read_hv_sched_clock_msr(void) >>> { >>> - return read_hv_clock_msr() - hv_sched_clock_offset; >>> + return (read_hv_clock_msr() - hv_sched_clock_offset) >>> + * (NSEC_PER_SEC / HV_CLOCK_HZ); >>> } >> >> kvmclock seems to have the same (pre-patch) code ... > > > kvm sched clock gets time from pvclock_clocksource_read() and > the time unit is nanosecond. So there is such issue in KVM code. > Ah, true, kvmclock is always 1Ghz so it's reading 'naturally' converts to ns. -- Vitaly