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Date:   Thu, 12 May 2022 21:04:17 +0200
From:   Heiko Carstens <hca@linux.ibm.com>
To:     Nick Desaulniers <ndesaulniers@google.com>
Cc:     Vasily Gorbik <gor@linux.ibm.com>,
        Alexander Gordeev <agordeev@linux.ibm.com>,
        Jonas Paulsson <paulsson@linux.vnet.ibm.com>,
        Ulrich Weigand <ulrich.weigand@de.ibm.com>,
        Masahiro Yamada <masahiroy@kernel.org>,
        Alexander Egorenkov <egorenar@linux.ibm.com>,
        Sven Schnelle <svens@linux.ibm.com>,
        Andreas Krebbel <krebbel@linux.ibm.com>,
        Nathan Chancellor <natechancellor@gmail.com>,
        linux-kernel@vger.kernel.org, linux-s390@vger.kernel.org
Subject: Re: [PATCH 0/8] s390: allow to build with llvm's integrated assembler
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References: <20220511120532.2228616-1-hca@linux.ibm.com>
 <CAKwvOdkXy0nhS-S+dOAsSO+mpj2dCuZ4aUTe=upPV8epfTA7Aw@mail.gmail.com>
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On Wed, May 11, 2022 at 12:48:34PM -0700, Nick Desaulniers wrote:
> On Wed, May 11, 2022 at 5:05 AM Heiko Carstens <hca@linux.ibm.com> wrote:
> >
> > A couple of patches which in result make it finally possible to build the
> > kernel for s390 with llvm's integrated assembler. Several configs build
> > without errors or warnings, and the kernel also works as expected.
> >
> > Note that patch 6 ("s390/boot: workaround llvm IAS bug") reveals a
> > miscompile. This looks like a bug in the instruction definitions of the mvc
> > and clc instructions(?). I'd like to ask people to look into this, since
> > this silently generated broken code.
> >
> > This patch series is based on linux-next, which contains two additional
> > required s390 specific patches to make llvm's IAS work.
> 
> I did a quick test of just a defconfig via:
> $ ARCH=s390 CROSS_COMPILE=s390x-linux-gnu- make CC=clang -j72 defconfig all
> and this assembled then booted in qemu for me. Thanks for the work
> that went into this!
> 
> Tested-by: Nick Desaulniers <ndesaulniers@google.com>

Will add this too. Thank you!