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=-0.6 required=3.0 tests=DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS,T_DKIM_INVALID autolearn=ham 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 DCB95C433EF for ; Tue, 19 Jun 2018 20:01:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 91C772075E for ; Tue, 19 Jun 2018 20:01:46 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="o5vIjI4S" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 91C772075E Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030635AbeFSUBn (ORCPT ); Tue, 19 Jun 2018 16:01:43 -0400 Received: from bombadil.infradead.org ([198.137.202.133]:50250 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1030407AbeFSUBm (ORCPT ); Tue, 19 Jun 2018 16:01:42 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=In-Reply-To:Content-Type:MIME-Version :References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=o5e71xF0DP1UwbQ0MedHn5Xi66q63qmw7BloKGBmJvI=; b=o5vIjI4S/fUhsWO0ZqJNlz8k4 CfE/385M9W8r+o1A86lUeWtEia8/TMEnlT0M2Dv01jIXcWOqPlchd+d0a49Ill2V0SicjAGPvUgfb QeVhiI+2rTt+O3bi6uU5YO/cVgFsS6OMYiu7vju6UWj4PPJtVW4KLa8ObzaEQunL7xhz6XH8NTLN2 tjIiCeF+23Ew00vMnXjafqP4mF7jShigiySNlAd5IE1k/xsyj0TMxDKcM7rEpBjsQtLaOjbDGdNug MyTvzzfYdakBbloDW88KCUrIO8sIqrLJIVKVzS9CIK8lwE3qyD0FTPHx325W7koFIazlyHSbaCzDW Vjcp3ZfuA==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=hirez.programming.kicks-ass.net) by bombadil.infradead.org with esmtpsa (Exim 4.90_1 #2 (Red Hat Linux)) id 1fVMoX-0002WQ-LG; Tue, 19 Jun 2018 20:01:17 +0000 Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id 41F82202A607E; Tue, 19 Jun 2018 22:01:15 +0200 (CEST) Date: Tue, 19 Jun 2018 22:01:15 +0200 From: Peter Zijlstra To: Thomas Gleixner Cc: Pavel Tatashin , steven.sistare@oracle.com, daniel.m.jordan@oracle.com, linux@armlinux.org.uk, schwidefsky@de.ibm.com, heiko.carstens@de.ibm.com, john.stultz@linaro.org, sboyd@codeaurora.org, x86@kernel.org, linux-kernel@vger.kernel.org, mingo@redhat.com, hpa@zytor.com, douly.fnst@cn.fujitsu.com, prarit@redhat.com, feng.tang@intel.com, pmladek@suse.com, gnomes@lxorguk.ukuu.org.uk Subject: Re: [PATCH v10 1/7] x86/tsc: remove tsc_disabled flag Message-ID: <20180619200115.GH2494@hirez.programming.kicks-ass.net> References: <20180615174204.30581-1-pasha.tatashin@oracle.com> <20180615174204.30581-2-pasha.tatashin@oracle.com> <20180619184654.GG2494@hirez.programming.kicks-ass.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.0 (2018-05-17) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Jun 19, 2018 at 09:12:45PM +0200, Thomas Gleixner wrote: > On Tue, 19 Jun 2018, Peter Zijlstra wrote: > > It does not; there is TSC usage even if you boot with notsc on. See how > > it does not clear X86_FEATURE_TSC for instance. > > Well, kinda. There is some stuff in the apic calibration which uses TSC > independent of tsc_disabled, but that's about it. Still, that precludes booting on hardware without TSC, so what's the point of having notsc? I'm all for killing the thing.