netdev - Re: [PATCH 2/3] arm: include: asm: unified: mask .syntax unified for clang

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Tue, 27 Jul 2021 10:55:26 -0700
From:   Nick Desaulniers <ndesaulniers@...gle.com>
To:     Pavo Banicevic <pavo.banicevic@...tura.hr>
Cc:     linux@...linux.org.uk, ast@...nel.org, daniel@...earbox.net,
        andrii@...nel.org, kafai@...com, songliubraving@...com, yhs@...com,
        john.fastabend@...il.com, kpsingh@...nel.org, nathan@...nel.org,
        ivan.khoronzhuk@...aro.org, linux-arm-kernel@...ts.infradead.org,
        linux-kernel@...r.kernel.org, netdev@...r.kernel.org,
        bpf@...r.kernel.org, clang-built-linux@...glegroups.com,
        matt.redfearn@...s.com, mingo@...nel.org, dvlasenk@...hat.com,
        juraj.vijtiuk@...tura.hr, robert.marko@...tura.hr,
        luka.perkov@...tura.hr, jakov.petrina@...tura.hr
Subject: Re: [PATCH 2/3] arm: include: asm: unified: mask .syntax unified for clang

On Tue, Jul 27, 2021 at 7:12 AM Pavo Banicevic
<pavo.banicevic@...tura.hr> wrote:
>
> From: Ivan Khoronzhuk <ivan.khoronzhuk@...aro.org>
>
> The samples/bpf reuses linux headers, with clang -emit-llvm,
> so this w/a is only for samples/bpf (samples/bpf/Makefile CLANG-bpf).
>
> It allows to build samples/bpf for arm on target board.
> In another way clang -emit-llvm generates errors like:
>
> <inline asm>:1:1: error: unknown directive
> .syntax unified
>
> I have verified it on clang 5, 6, 7, 8, 9, 10
> as on native platform as for cross-compiling. This decision is
> arguable, but it doesn't have impact on samples/bpf so it's easier
> just ignore it for clang, at least for now...

Did you test ARCH=arm kernel builds with Clang with this series applied?

>
> Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk@...aro.org>
> ---
>  arch/arm/include/asm/unified.h | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/arch/arm/include/asm/unified.h b/arch/arm/include/asm/unified.h
> index 1e2c3eb04353..8718f313e7c4 100644
> --- a/arch/arm/include/asm/unified.h
> +++ b/arch/arm/include/asm/unified.h
> @@ -11,7 +11,9 @@
>  #if defined(__ASSEMBLY__)
>         .syntax unified
>  #else
> -__asm__(".syntax unified");
> +
> +#ifndef __clang__
> +       __asm__(".syntax unified");
>  #endif
>
>  #ifdef CONFIG_CPU_V7M
> --
> 2.32.0
>


-- 
Thanks,
~Nick Desaulniers