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From:   Olof Johansson <olof@lixom.net>
Date:   Fri, 13 Jul 2018 08:01:34 -0700
Message-ID: <CAOesGMguQk_buucvNyKD6NmtdE0Re5_98Af+PME-HzZGHmeQGQ@mail.gmail.com>
Subject: Re: [PATCH] Revert "arm64: Use aarch64elf and aarch64elfb emulation
 mode variants"
To:     Will Deacon <will.deacon@arm.com>
Cc:     Paul Kocialkowski <contact@paulk.fr>,
        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>
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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.


-Olof