Re: [PATCH 1/7] powerpc/build: put sys_call_table in .data.rel.ro if RELOCATABLE

[Christophe Leroy <christophe.leroy@csgroup.eu>]

Le 14/09/2022 à 17:47, Nicholas Piggin a écrit :
> Const function pointers live in .data.rel.ro rather than .rodata because
> they must be relocated. This change prevents powerpc/32 from generating
> R_PPC_UADDR32 relocations (which are not handled). The sys_call_table is
> moved to writeable memory, but a later change will move it back.

Aren't you missing commit c7acee3d2f12 ("powerpc: align syscall table 
for ppc32") ?

I can't see any R_PPC_UADDR32 relocations generated by ppc4xx_defconfig 
+ CONFIG_RELOCATABLE unless I revert that commit.



> 
> After this patch, 44x_defconfig + CONFIG_RELOCATABLE boots to busybox.
> 
> Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
> ---
>   arch/powerpc/kernel/systbl.S | 4 ++++
>   1 file changed, 4 insertions(+)
> 
> diff --git a/arch/powerpc/kernel/systbl.S b/arch/powerpc/kernel/systbl.S
> index cb3358886203..0bec33e86f50 100644
> --- a/arch/powerpc/kernel/systbl.S
> +++ b/arch/powerpc/kernel/systbl.S
> @@ -12,7 +12,11 @@
>   
>   #include <asm/ppc_asm.h>
>   
> +#ifdef CONFIG_RELOCATABLE
> +.section .data.rel.ro,"aw"
> +#else
>   .section .rodata,"a"
> +#endif
>   
>   #ifdef CONFIG_PPC64
>   	.p2align	3