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=-6.3 required=3.0 tests=DKIM_ADSP_CUSTOM_MED, DKIM_INVALID,DKIM_SIGNED,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 93794C2D0F6 for ; Wed, 13 May 2020 02:36:10 +0000 (UTC) Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (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 63794206F5 for ; Wed, 13 May 2020 02:36:10 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="Ifk0J4Xm" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 63794206F5 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=gmail.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=xen-devel-bounces@lists.xenproject.org Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1jYhFQ-0007ho-Lu; Wed, 13 May 2020 02:35:52 +0000 Received: from us1-rack-iad1.inumbo.com ([172.99.69.81]) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1jYhFO-0007hj-TV for xen-devel@lists.xenproject.org; Wed, 13 May 2020 02:35:50 +0000 X-Inumbo-ID: 75035d46-94c2-11ea-ae69-bc764e2007e4 Received: from mail-lf1-x142.google.com (unknown [2a00:1450:4864:20::142]) by us1-rack-iad1.inumbo.com (Halon) with ESMTPS id 75035d46-94c2-11ea-ae69-bc764e2007e4; Wed, 13 May 2020 02:35:50 +0000 (UTC) Received: by mail-lf1-x142.google.com with SMTP id a9so12267959lfb.8 for ; Tue, 12 May 2020 19:35:50 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=E9N4W2DwvaFGv1eRMFSJ1p6aZv3XUhtfCnoLChztmVA=; b=Ifk0J4Xmf2rqOyNut+l9VVX80YJg2wQ5sphfC0LxSYuXdTLYlJcoxKdx3Y+hlm/Qoa xVrwuYwUwvG2BZGFyZpR8wSMGB/mHlsCOwBe3mNzYoPf0h/jssE9VLhKEaGhripYcdq6 ZGOACzEDqsNverHqjLhPIsJbhiO0+GrB2mVqB7rtIkGGH4M+F9MOYoy6pTDIpNktjHKk 1457IrfBxMYUtQu+drKkQEf9dWEETSEW+rBGkZdorb8Kjihzrkf8mjKa+vTdnGqJa27X k02lISbThujYMBuBHHsjn/5/aSIFePHF0cbMrCx8DODvw2hvINXs0wKv53uQtYXQUc4B nRMw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=E9N4W2DwvaFGv1eRMFSJ1p6aZv3XUhtfCnoLChztmVA=; b=B4zReaj4kSA9DJYPEyE36fx+dpsyBZuwFqB2dyDq0XLQoExm4Gesuhzr7Ffto/vgRO 6ngxn8uVultBsOoOlGxz/ruK8+1Lw4KBbDYgd9E0TM9v3eKiDDPbi7KL0/pJbd2isDEO tgyuelNpdMU9KXB7aiuSdwS1tT17CU4nSBDCjPVpb8yw8YzWJSk7ZgbrkE7Nh+Uuhp/B NARyLB4rgoTdhJ0L8/KaTSdBBwDrluhXupk26wIjEBhlr1zMm8h6sCR63tilruRIiNZW +MHWq+taFuZp+ZxEDE18ktf/qkmvU7WIHwC0BFQFivb7XBa1EWDz+mXmRT5sV+9J7kOH Sppg== X-Gm-Message-State: AOAM532Tx5XrMftimEvgu/MQh98RKBIrAd/QTUCt01NukyXkClMBhUDa Ptv+tNK3T2zVMg/mtBNahsPkQx7utNIM+JGC6o8= X-Google-Smtp-Source: ABdhPJxs0TdijdGhSlbSI5fXuLNpbmbV92urJRIUVRWarQ8/4SvmZiU6YxqrO2jP1zqhMquADG0OG0qPwdqw7EmtpZ0= X-Received: by 2002:ac2:4c3b:: with SMTP id u27mr16203886lfq.212.1589337349132; Tue, 12 May 2020 19:35:49 -0700 (PDT) MIME-Version: 1.0 References: <20200512191116.6851-1-andrew.cooper3@citrix.com> In-Reply-To: <20200512191116.6851-1-andrew.cooper3@citrix.com> From: Jason Andryuk Date: Tue, 12 May 2020 22:35:38 -0400 Message-ID: Subject: Re: [PATCH] x86/build: Unilaterally disable -fcf-protection To: Andrew Cooper Content-Type: text/plain; charset="UTF-8" X-BeenThere: xen-devel@lists.xenproject.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Cc: Stefan Bader , Xen-devel , Wei Liu , Jan Beulich , =?UTF-8?Q?Roger_Pau_Monn=C3=A9?= Errors-To: xen-devel-bounces@lists.xenproject.org Sender: "Xen-devel" On Tue, May 12, 2020 at 3:11 PM Andrew Cooper wrote: > > See comment for details. Works around a GCC-9 bug which breaks the build on > Ubuntu. > > Reported-by: Jason Andryuk > Signed-off-by: Andrew Cooper Tested-by: Jason Andryuk Reviewed-by: Jason Andryuk > diff --git a/xen/arch/x86/arch.mk b/xen/arch/x86/arch.mk > index 2a51553edb..93e30e4bea 100644 > --- a/xen/arch/x86/arch.mk > +++ b/xen/arch/x86/arch.mk > @@ -67,6 +67,15 @@ CFLAGS-$(CONFIG_INDIRECT_THUNK) += -mindirect-branch=thunk-extern > CFLAGS-$(CONFIG_INDIRECT_THUNK) += -mindirect-branch-register > CFLAGS-$(CONFIG_INDIRECT_THUNK) += -fno-jump-tables > > +# Xen doesn't support CET-IBT yet. At a minimum, logic is required to > +# enable it for supervisor use, but the Livepatch functionality needs > +# to learn not to overwrite ENDBR64 instructions. Is the problem that existing functions start with ENDBR64, but the livepatch overwrites with a "real" instruction? Regards, Jason