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=-1.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,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 3EEAAC433DF for ; Wed, 24 Jun 2020 23:54:21 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 065C820672 for ; Wed, 24 Jun 2020 23:54:21 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="jySJuhmC" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 065C820672 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.intel.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References:Message-ID: Subject:To:From:Date:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=lE6DxCAfbbU0fdjTGyfhrOyATBjptdtJG+QF9bm12sI=; b=jySJuhmCZwq7z7wJaAE7ykGz7 a7wcu53sYfGFKwMQ4zKOJ5MKNDQ670f0YSyF6xwzN26pEHdGD0ifWcXubQ7z1vFVKFoTH/gNhz/lO vEzAOJR5z3XhP/elRwoRMuhdXY8b997b2O6HdUDArIzbsuwVU/UrKRnBNhON3AxEEUMeIt8hRVK5K c0BraJsMx/TRCAt7qxwzd40Gd6QyGpYSYL3Nfr5Q4OXGWIZozJmCFB44etSdFZu4B0rqPWUXEWprb hiOedYRCTe1RqVofgusTLA9UjZilSlyU94clnliFOtS6Sya785AMSKtMZ+Iyj+lS2qbMPfdCD8c0S Vfcd7AVOA==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1joFBI-0008Mw-3z; Wed, 24 Jun 2020 23:51:52 +0000 Received: from mga09.intel.com ([134.134.136.24]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1joFBC-0008Jt-MI for linux-arm-kernel@lists.infradead.org; Wed, 24 Jun 2020 23:51:47 +0000 IronPort-SDR: WqVK8tj24iu9ef2+UCxc5MiKmqKYFjvl8QygyxWIR+F6moxl0bDUe80Ufey45ixNWOvrpm6z7X b7nWFVHrPezQ== X-IronPort-AV: E=McAfee;i="6000,8403,9662"; a="146176291" X-IronPort-AV: E=Sophos;i="5.75,277,1589266800"; d="scan'208";a="146176291" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga004.jf.intel.com ([10.7.209.38]) by orsmga102.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 24 Jun 2020 16:51:44 -0700 IronPort-SDR: aIRwRfjfYOdQKt3phW/InEgXxtOGI/IQstcHLZdz056+zuNv6rXZAztOwLlpT5Cd5ScDQD9lHH /YX4kqyPmgHA== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.75,277,1589266800"; d="scan'208";a="423544015" Received: from tassilo.jf.intel.com (HELO tassilo.localdomain) ([10.7.201.21]) by orsmga004.jf.intel.com with ESMTP; 24 Jun 2020 16:51:44 -0700 Received: by tassilo.localdomain (Postfix, from userid 1000) id 463F2301BA1; Wed, 24 Jun 2020 16:51:44 -0700 (PDT) Date: Wed, 24 Jun 2020 16:51:44 -0700 From: Andi Kleen To: Nick Desaulniers Subject: Re: [PATCH 17/22] arm64: vdso: disable LTO Message-ID: <20200624235144.GD818054@tassilo.jf.intel.com> References: <20200624203200.78870-1-samitolvanen@google.com> <20200624203200.78870-18-samitolvanen@google.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-arch , "maintainer:X86 ARCHITECTURE \(32-BIT AND 64-BIT\)" , Kees Cook , "Paul E. McKenney" , Kernel Hardening , Greg Kroah-Hartman , Masahiro Yamada , Linux Kbuild mailing list , LKML , clang-built-linux , Sami Tolvanen , linux-pci@vger.kernel.org, Will Deacon , Linux ARM Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Wed, Jun 24, 2020 at 02:09:40PM -0700, Nick Desaulniers wrote: > On Wed, Jun 24, 2020 at 1:58 PM Nick Desaulniers > wrote: > > > > On Wed, Jun 24, 2020 at 1:33 PM Sami Tolvanen wrote: > > > > > > Filter out CC_FLAGS_LTO for the vDSO. > > > > Just curious about this patch (and the following one for x86's vdso), > > do you happen to recall specifically what the issues with the vdso's > > are? > > + Andi (tangential, I actually have a bunch of tabs open with slides > from http://halobates.de/ right now) > 58edae3aac9f2 > 67424d5a22124 > $ git log -S DISABLE_LTO I think I did it originally because the vDSO linker step didn't do all the magic needed for gcc LTO. But it also doesn't seem to be very useful for just a few functions that don't have complex interactions, and somewhat risky for violating some assumptions. -Andi _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel