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Message-ID: <dcf5d2e506b77e835e6175311054f3be9754fa47.camel@paulk.fr>
Subject: Re: [PATCH] Revert "arm64: Use aarch64elf and aarch64elfb emulation
 mode variants"
From:   Paul Kocialkowski <contact@paulk.fr>
To:     Olof Johansson <olof@lixom.net>, Will Deacon <will.deacon@arm.com>
Cc:     Laura Abbott <labbott@redhat.com>,
        Catalin Marinas <catalin.marinas@arm.com>,
        Linux ARM Mailing List <linux-arm-kernel@lists.infradead.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Michal Marek <michal.lkml@markovi.net>
Date:   Fri, 13 Jul 2018 17:08:09 +0200
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Hi,

On Fri, 2018-07-13 at 08:01 -0700, Olof Johansson wrote:
> On Fri, Jul 13, 2018 at 7:59 AM, Olof Johansson <olof@lixom.net> wrote:
> > On Tue, Jul 10, 2018 at 10:36:16AM +0100, Will Deacon wrote:
> > > On Tue, Jul 10, 2018 at 11:30:39AM +0200, Paul Kocialkowski wrote:
> > > > On Tue, 2018-07-10 at 10:01 +0100, Will Deacon wrote:
> > > > > Thanks, Laura.
> > > > > 
> > > > > I'll take this as a fix, and add a comment to the Makefile to justify
> > > > > why we need the linux target.
> > > > 
> > > > So this comes down to either breaking fedora/debian toolchains (that
> > > > don't support elf emulation mode) or breaking bare-metal toolchains
> > > > (that don't support linux emulation mode).
> > > > 
> > > > Since Linux is a bare-metal project that does not technically require
> > > > the linux target (who said using "Linux" for all things is confusing?),
> > > > I think it should aim for the elf target in the long term.
> > > > 
> > > > But well, breaking Linux build in common distros isn't good either, so I
> > > > guess it makes sense to revert this while distros toolchains are being
> > > > fixed. Hopefully, it won't take too long.
> > > > 
> > > > What do you think?
> > > 
> > > Yes, we need to revert the change since it's a regression otherwise. I think
> > > the best course of action here would be to find a way that we can either
> > > tell the linker that it doesn't need the missing linker scripts because
> > > we're providing our own, or find a way to pass different LD flags depending
> > > on whether or not we have a linux toolchain.
> > > 
> > > For now, I've pushed the revert to for-next/fixes.
> > 
> > Hi Will,
> > 
> > This is regressed in mainline as well. But I think we can just use a (slightly
> > improved) ld-option here? I checked it for x86 regression since it uses the
> > one-argument version. Patch is here, can you pick that up instead and get it in
> > for 4.18-rc?
> > 
> > Thanks,
> > 
> > 
> > -Olof
> > 
> > From 0d73b2d1774d5edce20aac919ba356b61d098646 Mon Sep 17 00:00:00 2001
> > From: Olof Johansson <olof@lixom.net>
> > Date: Fri, 13 Jul 2018 07:56:11 -0700
> > Subject: [PATCH] arm64: Fix build on some toolchains
> > 
> > Not all toolchains have the baremetal elf targets, RedHat/Fedora ones in
> > particular. So, probe for whether it's available and use the previous
> > (linux) targets if it isn't.
> > 
> > Fixes: 38fc42486775 ("arm64: Use aarch64elf and aarch64elfb emulation mode variants")
> > Signed-off-by: Olof Johansson <olof@lixom.net>
> 
> Of course, please add:
> Reported-by: Laura Abbott <labbott@redhat.com>
> 
> or other suitable tag. Sloppy of me to miss.

Thanks for taking care of this patch!

I will definitely try it when I get the chance.

Cheers,

Paul

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