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=-2.2 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 23030C432C1 for ; Tue, 24 Sep 2019 00:35:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0377D207FD for ; Tue, 24 Sep 2019 00:35:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2503640AbfIXAfB (ORCPT ); Mon, 23 Sep 2019 20:35:01 -0400 Received: from mga04.intel.com ([192.55.52.120]:18647 "EHLO mga04.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388800AbfIXAfA (ORCPT ); Mon, 23 Sep 2019 20:35:00 -0400 X-Amp-Result: UNKNOWN X-Amp-Original-Verdict: FILE UNKNOWN X-Amp-File-Uploaded: False Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by fmsmga104.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 23 Sep 2019 17:35:00 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.64,542,1559545200"; d="scan'208";a="203247391" Received: from sjchrist-coffee.jf.intel.com (HELO linux.intel.com) ([10.54.74.41]) by fmsmga001.fm.intel.com with ESMTP; 23 Sep 2019 17:35:00 -0700 Date: Mon, 23 Sep 2019 17:35:00 -0700 From: Sean Christopherson To: Paolo Bonzini Cc: Andrea Arcangeli , Vitaly Kuznetsov , "Dr. David Alan Gilbert" , Marcelo Tosatti , Peter Xu , kvm@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 15/17] KVM: retpolines: x86: eliminate retpoline from vmx.c exit handlers Message-ID: <20190924003459.GA13147@linux.intel.com> References: <20190920212509.2578-1-aarcange@redhat.com> <20190920212509.2578-16-aarcange@redhat.com> <87o8zb8ik1.fsf@vitty.brq.redhat.com> <7329012d-0b3b-ce86-f58d-3d2d5dc5a790@redhat.com> <20190923190514.GB19996@redhat.com> <20190923202349.GL18195@linux.intel.com> <20190923210838.GA23063@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: 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, Sep 24, 2019 at 02:16:36AM +0200, Paolo Bonzini wrote: > On 23/09/19 23:08, Andrea Arcangeli wrote: > > The two most attractive options to me remains what I already have > > implemented under #ifdef CONFIG_RETPOLINE with direct calls > > (optionally replacing the "if" with a small "switch" still under > > CONFIG_RETPOLINE if we give up the prioritization of the checks), or > > the replacement of kvm_vmx_exit_handlers with a switch() as suggested > > by Vitaly which would cleanup some code. > > > > The intermediate solution that makes "const" work, has the cons of > > forcing to parse EXIT_REASON_VMCLEAR and the other vmx exit reasons > > twice, first through a pointer to function (or another if or switch > > statement) then with a second switch() statement. > > I agree. I think the way Andrea did it in his patch may not the nicest > but is (a bit surprisingly) the easiest and most maintainable. Heh, which patch? The original patch of special casing the high priority exits?