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=2.4 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,HTML_MESSAGE,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 79362C83001 for ; Thu, 30 Apr 2020 08:17:07 +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 4A0582073E for ; Thu, 30 Apr 2020 08:17:07 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="ouKJPbiX" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 4A0582073E 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 1jU4NK-0002uR-SD; Thu, 30 Apr 2020 08:16:54 +0000 Received: from us1-rack-iad1.inumbo.com ([172.99.69.81]) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1jU4NJ-0002uM-4S for xen-devel@lists.xen.org; Thu, 30 Apr 2020 08:16:53 +0000 X-Inumbo-ID: f2042468-8aba-11ea-ae69-bc764e2007e4 Received: from mail-oi1-x234.google.com (unknown [2607:f8b0:4864:20::234]) by us1-rack-iad1.inumbo.com (Halon) with ESMTPS id f2042468-8aba-11ea-ae69-bc764e2007e4; Thu, 30 Apr 2020 08:16:51 +0000 (UTC) Received: by mail-oi1-x234.google.com with SMTP id a2so4481227oia.11 for ; Thu, 30 Apr 2020 01:16:51 -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=PSbV9BzdXx84MTWhjheATmsVhCcessEhtCWJHTsqRdY=; b=ouKJPbiXN4f5LLaS3L0cX5S+saFHmpCa7ITYX/xngYnkKNA53qTyPEnzuTp9mzxFSF ZgD/FpHyfdPXqsY/WmBOR4SQ1uUQ5TTrQTY9LEac9YGpQJnmyPtI5CGtWmrAlHi+gGsa Q6SsF8C3DX8+EBbHqVCYz7tSzt6FVeTy6JZVCZLJC+FLwO/jbUcABw1THZkRZS9u3/tG qgnvmbpYk2tU/zD7YiUfH9R4V4AWmHJABKjMViqkCbRF0616M9GLrshkk2GmagEhjmjU WEoG3w/SRlTj5nuUk96fm3l9N0Di7RXB0be7+HJWNZQUkLnkLat8KUh0PFYcaqqaDVrr yzbw== 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=PSbV9BzdXx84MTWhjheATmsVhCcessEhtCWJHTsqRdY=; b=iOEgGLPdxLgPV9dyayHz64gtCqpggTr367Dz03pgCRsOQPEhtILVypwcdYNxOx0gy9 rNIBGdopL5kxl2jPxZ0SFbaJdXfNFzpyUT8RTJ1aHGKlsL6yuPeSaSRpkZLoNdI5+t/q zVqfNEa1cLStkjDmuRzWAJwW+tEtfp0govZv4T+ZOceBB0Au8SoaDUSkT1Oj76/hTBRI 1yH+BYS90vIJjiQG6RlcyBg8pecJSn5ms4Fdcu6u3QhbxM7n3eS6QuNBBIqjvz//9lJ8 dUR58k8FZboM4AZDshhrrEpdloM/v6xR3pEZJnk4xhpszEW7kFiC6cXMn/EJkie7NeMl shEA== X-Gm-Message-State: AGi0PuYY6pSAscahzvN0yaEF2Yy4DtyzYRi4buWZE0prJxxDXYNo9o+i p9IE/QSmYSmJGuP56aA3iP3ZVMzWeb8kyVktIQY= X-Google-Smtp-Source: APiQypJLsWzZb5LbKoUVfTM9sohctVRyJ5FJmzybE4/l/fHoVNbNPe++FfEma1bfm7pFoqAuCEb+ut9hUuVqW06XofM= X-Received: by 2002:aca:c78d:: with SMTP id x135mr894063oif.91.1588234611251; Thu, 30 Apr 2020 01:16:51 -0700 (PDT) MIME-Version: 1.0 References: In-Reply-To: From: Ayush Dosaj Date: Thu, 30 Apr 2020 13:46:39 +0530 Message-ID: Subject: Re: Xen Compilation Error on Ubuntu 20.04 To: Andrew Cooper Content-Type: multipart/alternative; boundary="000000000000d2df0805a47daf94" 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: xen-devel@lists.xen.org Errors-To: xen-devel-bounces@lists.xenproject.org Sender: "Xen-devel" --000000000000d2df0805a47daf94 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Hi Andrew, Xen Development team. I compiled and installed Xen by appending -fcf-protection=3Dnone to CFLAGS = on Ubuntu 20.04 but it still crashes on startup. On Wed, Apr 29, 2020 at 10:58 PM Ayush Dosaj wrote: > Awesome, thanks! > > On Wed, Apr 29, 2020 at 10:55 PM Andrew Cooper > wrote: > >> On 29/04/2020 18:17, Ayush Dosaj wrote: >> > Hi Xen development team, >> > >> > I am Ayush. I compiled Xen Hypervisor from source on Ubuntu 20.04 >> > machine running on an intel-i9 CPU. >> > I am getting compilation error due to the following two flags. >> > Error: error: =E2=80=98-mindirect-branch=E2=80=99 and =E2=80=98-fcf-pr= otection=E2=80=99 are not >> compatible. >> > >> > Complete Error logs can be found at >> https://paste.ubuntu.com/p/xvvyPnhW5c/ >> > >> > And when I compiled Xen commenting the two flags in Rules.mk file, it >> > compiles and installs properly but on boot-up i see a blank black scre= en >> > and i am stuck there. >> >> That is a GCC bug (these options are actually fine in combination). It >> got fixed earlier today in master, and backported for GCC 9.4 >> >> You can work around it by appending -fcf-protection=3Dnone to CFLAGS >> >> I wouldn't try editing the logic around -mindirect-branch, as that is >> related to retpoline safety for Spectre v2, and probably relies on the >> build matching the code. >> >> ~Andrew >> > > > -- > Ayush Dosaj > VIT Vellore > > --=20 Ayush Dosaj --000000000000d2df0805a47daf94 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable
Hi Andrew,= Xen Development team.

I compiled and installed Xen by appending -fcf-protect= ion=3Dnone to CFLAGS on Ubuntu 20.04 but it still crashes on startup.
=

On Wed, Apr 29, 2020 at 10:58 PM Ayush Dosaj <ayushdosaj2313@gmail.com> wrote:
Awesome, thanks!

On Wed, Apr 29, 2020 at 10:55 PM Andrew= Cooper <= andrew.cooper3@citrix.com> wrote:
On 29/04/2020 18:17, Ayush Dosaj wrote:
> Hi Xen development team,
>
> I am Ayush. I compiled Xen Hypervisor from source on Ubuntu 20.04
> machine running on an intel-i9 CPU.
> I am getting compilation error due to the following two flags.
> Error: error: =E2=80=98-mindirect-branch=E2=80=99 and =E2=80=98-fcf-pr= otection=E2=80=99 are not compatible.
>
> Complete Error logs can be found at https://paste.ubuntu.= com/p/xvvyPnhW5c/
>
> And when I compiled Xen commenting the two flags in Rules.mk file, it<= br> > compiles and installs properly but on boot-up i see a blank black scre= en
> and i am stuck there.

That is a GCC bug (these options are actually fine in combination).=C2=A0 I= t
got fixed earlier today in master, and backported for GCC 9.4

You can work around it by appending -fcf-protection=3Dnone to CFLAGS

I wouldn't try editing the logic around -mindirect-branch, as that is related to retpoline safety for Spectre v2, and probably relies on the
build matching the code.

~Andrew


--
Ayush Dosaj
VIT Vellore

=


--
Ayus= h Dosaj

--000000000000d2df0805a47daf94--