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Date:   Fri, 13 May 2022 11:18:08 +0200
From:   Vasily Gorbik <gor@linux.ibm.com>
To:     Heiko Carstens <hca@linux.ibm.com>
Cc:     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>,
        Nick Desaulniers <ndesaulniers@google.com>,
        linux-kernel@vger.kernel.org, linux-s390@vger.kernel.org
Subject: Re: [PATCH 2/8] s390/alternatives: remove padding generation code
Message-ID: <your-ad-here.call-01652433488-ext-2779@work.hours>
References: <20220511120532.2228616-1-hca@linux.ibm.com>
 <20220511120532.2228616-3-hca@linux.ibm.com>
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On Wed, May 11, 2022 at 02:05:26PM +0200, Heiko Carstens wrote:
> clang fails to handle ".if" statements in inline assembly which are heavily
> used in the alternatives code.
> 
> To work around this remove this code, and enforce that users of
> alternatives must specify original and alternative instruction sequences
> which have identical sizes. Add a compile time check with two ".org"
> statements similar to arm64.
> 
> In result not only clang can handle this, but also quite a lot of code can
> be removed.
> 
> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
> ---
>  arch/s390/include/asm/alternative-asm.h | 76 +++-----------------
>  arch/s390/include/asm/alternative.h     | 93 ++++++-------------------
>  arch/s390/kernel/alternative.c          | 61 +---------------
>  3 files changed, 31 insertions(+), 199 deletions(-)

Acked-by: Vasily Gorbik <gor@linux.ibm.com>