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=-2.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 6D447C2BA19 for ; Wed, 22 Apr 2020 00:42:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 417E520706 for ; Wed, 22 Apr 2020 00:42:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726437AbgDVAmP (ORCPT ); Tue, 21 Apr 2020 20:42:15 -0400 Received: from mga11.intel.com ([192.55.52.93]:2830 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726012AbgDVAmO (ORCPT ); Tue, 21 Apr 2020 20:42:14 -0400 IronPort-SDR: +Twdksnq26JzTYJDmHUisDqyVktSVfsisxAnB3NUiMOPTIkRm6yXgrdB0BnyUECdNe8qr22isH lZ8thfOuKfdg== X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga004.jf.intel.com ([10.7.209.38]) by fmsmga102.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 21 Apr 2020 17:42:13 -0700 IronPort-SDR: SiSuhn44bcVmf+oXXggLxCXgVmew1IaBu6Dm3ZQp34xgCpHFLtjWqwxG5u5Xus/DDQtAE1glEx fCSYhjuUrshA== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.72,412,1580803200"; d="scan'208";a="402363527" Received: from sjchrist-coffee.jf.intel.com (HELO linux.intel.com) ([10.54.74.202]) by orsmga004.jf.intel.com with ESMTP; 21 Apr 2020 17:42:13 -0700 Date: Tue, 21 Apr 2020 17:42:13 -0700 From: Sean Christopherson To: Thomas Gleixner Cc: Christoph Hellwig , LKML , x86@kernel.org, Kees Cook , Paolo Bonzini , Thomas Lendacky , Juergen Gross , Boris Ostrovsky Subject: Re: [patch 00/15] x86/tlb: Unexport per-CPU tlbstate Message-ID: <20200422004213.GC17836@linux.intel.com> References: <20200419203137.214111265@linutronix.de> <20200420092045.GC24518@infradead.org> <87sggyax05.fsf@nanos.tec.linutronix.de> <20200421080905.GF11134@linux.intel.com> <87tv1durws.fsf@nanos.tec.linutronix.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <87tv1durws.fsf@nanos.tec.linutronix.de> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Apr 21, 2020 at 11:09:07AM +0200, Thomas Gleixner wrote: > Sean Christopherson writes: > > > On Mon, Apr 20, 2020 at 07:27:06PM +0200, Thomas Gleixner wrote: > >> Christoph Hellwig writes: > >> > Just looking over some exports at the end of the series (and thus > >> > ignoring bisection issues): > >> > > >> > - Is there any good reason to keep __flush_tlb_all inline vs moving it > >> > out of line and kill the flush_tlb_local and flush_tlb_global exports. > >> > Also there is just a single modular users in SVM, I wonder if there is > >> > any way to get rid of that one as well. > >> > >> I'll have a look again. > > > > Regarding the SVM case, the only usage is for a TLB errata. At a glance, > > svm_init_erratum_383() and is_erratum_383() don't use any KVM hooks, i.e. I > > don't see anything that would prevent moving those to .../kernel/cpu/amd.c. > > Right, but that would trade one export vs. two SVM errata specific > exports. Not really a win. True. I was thinking the svm_init_erratum_383() call could be moved to init_amd(), assuming the MSR's magic bit 47 is "safe" outside of SVM enabled, but that's probably not worth risking the potential for breakage unless you really want to hide __flush_tlb_all().