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Message-ID: <1ae25437-b190-418d-a4e0-aa17d6de59bf@huawei.com>
Date: Thu, 22 Feb 2024 19:32:03 +0800
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Subject: Re: [PATCH -next] arm32: enable HAVE_LD_DEAD_CODE_DATA_ELIMINATION
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To: Arnd Bergmann <arnd@arndb.de>, <linux-arm-kernel@lists.infradead.org>,
	<linux-kernel@vger.kernel.org>
CC: Russell King <linux@armlinux.org.uk>, Andrew Davis <afd@ti.com>, Andrew
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	<kirill.shutemov@linux.intel.com>, Geert Uytterhoeven
	<geert+renesas@glider.be>, Jonathan Corbet <corbet@lwn.net>, Mike Rapoport
	<rppt@kernel.org>, Eric DeVolder <eric.devolder@oracle.com>, Rob Herring
	<robh@kernel.org>, Thomas Gleixner <tglx@linutronix.de>, Linus Walleij
	<linus.walleij@linaro.org>
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From: "liuyuntao (F)" <liuyuntao12@huawei.com>
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On 2024/2/22 17:52, Arnd Bergmann wrote:
> On Wed, Feb 21, 2024, at 16:51, Arnd Bergmann wrote:
>> I have given your patch some build testing with random
>> configurations in my build setup and it seems to work
>> fine with gcc/binutils, but unfortunately I came across
>> a link failure using clang/lld:
> 
> I ran into another bug now, this time with CONFIG_XIP_KERNEL=y:
> 
> no __ex_table in file: vmlinux
> Failed to sort kernel tables
> make[4]: *** [scripts/Makefile.vmlinux:37: vmlinux] Error 1
> 
> Essentially you have to modify arch/arm/kernel/vmlinux-xip.lds.S
> the same way as vmlinux.lds.S:
>
Thanks a lot. I didn't consider this situation. I will take your advice. 
Thanks again.

> --- a/arch/arm/kernel/vmlinux-xip.lds.S
> +++ b/arch/arm/kernel/vmlinux-xip.lds.S
> @@ -63,7 +63,7 @@ SECTIONS
>          . = ALIGN(4);
>          __ex_table : AT(ADDR(__ex_table) - LOAD_OFFSET) {
>                  __start___ex_table = .;
> -               ARM_MMU_KEEP(*(__ex_table))
> +               ARM_MMU_KEEP(KEEP(*(__ex_table)))
>                  __stop___ex_table = .;
>          }
>   
> @@ -83,7 +83,7 @@ SECTIONS
>          }
>          .init.arch.info : {
>                  __arch_info_begin = .;
> -               *(.arch.info.init)
> +               KEEP(*(.arch.info.init))
>                  __arch_info_end = .;
>          }
>          .init.tagtable : {
> 
> 
> The pv_table is not needed for XIP_KERNEL=y because that
> requires not patching the kernel.
> 
>      Arnd