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Date: Wed, 9 Mar 2022 18:45:13 +0000
From: Catalin Marinas <catalin.marinas@arm.com>
To: Nathan Chancellor <nathan@kernel.org>
Cc: Marc Zyngier <maz@kernel.org>, linux-arm-kernel@lists.infradead.org,
	kernel-team@android.com, James Morse <james.morse@arm.com>,
	Nick Desaulniers <ndesaulniers@google.com>,
	Will Deacon <will@kernel.org>, llvm@lists.linux.dev
Subject: Re: [PATCH] arm64: Paper over ARM_SMCCC_ARCH_WORKAROUND_3 Clang issue
Message-ID: <Yij1uUwvnsxjbvR+@arm.com>
References: <20220309155716.3988480-1-maz@kernel.org>
 <YijftpaApSJWuZ3m@dev-arch.thelio-3990X>
 <Yijo7Nmt3AiP1uLH@dev-arch.thelio-3990X>
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In-Reply-To: <Yijo7Nmt3AiP1uLH@dev-arch.thelio-3990X>

On Wed, Mar 09, 2022 at 10:50:36AM -0700, Nathan Chancellor wrote:
> This diff seems like a somewhat proper solution, as __READ_ONCE() cannot
> be used in assembly, but I am open to other suggestions.
> 
> diff --git a/arch/arm64/include/asm/rwonce.h b/arch/arm64/include/asm/rwonce.h
> index 1bce62fa908a..56f7b1d4d54b 100644
> --- a/arch/arm64/include/asm/rwonce.h
> +++ b/arch/arm64/include/asm/rwonce.h
> @@ -5,7 +5,7 @@
>  #ifndef __ASM_RWONCE_H
>  #define __ASM_RWONCE_H
>  
> -#ifdef CONFIG_LTO
> +#if defined(CONFIG_LTO) && !defined(__ASSEMBLY__)
>  
>  #include <linux/compiler_types.h>
>  #include <asm/alternative-macros.h>
> @@ -66,7 +66,7 @@
>  })
>  
>  #endif	/* !BUILD_VDSO */
> -#endif	/* CONFIG_LTO */
> +#endif	/* CONFIG_LTO && !__ASSEMBLY__ */

Thanks Nathan. Would you please send a proper patch for this? I'd go
with your proposal as it seems more related to LTO than Marc's patch ;).

-- 
Catalin