Re: [PATCH v5 mips-next 5/9] MIPS: vmlinux.lds.S: explicitly catch .rel.dyn symbols

From: Nathan Chancellor <natechancellor@gmail.com>
To: Alexander Lobakin <alobakin@pm.me>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>,
	Arnd Bergmann <arnd@arndb.de>,
	Nick Desaulniers <ndesaulniers@google.com>,
	Huacai Chen <chenhuacai@kernel.org>,
	Pei Huang <huangpei@loongson.cn>,
	Kees Cook <keescook@chromium.org>,
	Fangrui Song <maskray@google.com>,
	Jiaxun Yang <jiaxun.yang@flygoat.com>,
	Ralf Baechle <ralf@linux-mips.org>,
	Corey Minyard <cminyard@mvista.com>,
	linux-mips@vger.kernel.org, linux-kernel@vger.kernel.org,
	linux-arch@vger.kernel.org, stable@vger.kernel.org,
	clang-built-linux@googlegroups.com
Subject: Re: [PATCH v5 mips-next 5/9] MIPS: vmlinux.lds.S: explicitly catch .rel.dyn symbols
Date: Sun, 10 Jan 2021 18:28:09 -0700	[thread overview]
Message-ID: <20210111012809.GA2918900@ubuntu-m3-large-x86> (raw)
In-Reply-To: <20210110115546.30970-5-alobakin@pm.me>

On Sun, Jan 10, 2021 at 11:56:34AM +0000, Alexander Lobakin wrote:
> According to linker warnings, both GCC and LLVM generate '.rel.dyn'
> symbols:
> 
> mips-alpine-linux-musl-ld: warning: orphan section `.rel.dyn'
> from `init/main.o' being placed in section `.rel.dyn'
> 
> Link-time assertion shows that this section is sometimes empty,
> sometimes not, depending on machine bitness and the compiler [0]:
> 
>   LD      .tmp_vmlinux.kallsyms1
> mips64-linux-gnu-ld: Unexpected run-time relocations (.rel) detected!
> 
> Just use the ARM64 approach and declare it in vmlinux.lds.S closer
> to __init_end.
> 
> [0] https://lore.kernel.org/linux-mips/20210109111259.GA4213@alpha.franken.de
> 
> Reported-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
> Signed-off-by: Alexander Lobakin <alobakin@pm.me>

Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>

> ---
>  arch/mips/kernel/vmlinux.lds.S | 5 +++++
>  1 file changed, 5 insertions(+)
> 
> diff --git a/arch/mips/kernel/vmlinux.lds.S b/arch/mips/kernel/vmlinux.lds.S
> index 10d8f0dcb76b..70bba1ff08da 100644
> --- a/arch/mips/kernel/vmlinux.lds.S
> +++ b/arch/mips/kernel/vmlinux.lds.S
> @@ -137,6 +137,11 @@ SECTIONS
>  	PERCPU_SECTION(1 << CONFIG_MIPS_L1_CACHE_SHIFT)
>  #endif
>  
> +	.rel.dyn : ALIGN(8) {
> +		*(.rel)
> +		*(.rel*)
> +	}
> +
>  #ifdef CONFIG_MIPS_ELF_APPENDED_DTB
>  	.appended_dtb : AT(ADDR(.appended_dtb) - LOAD_OFFSET) {
>  		*(.appended_dtb)
> -- 
> 2.30.0
> 
>