Re: [PATCH 1/3] powerpc/vdso: augment VDSO32 functions to support 64 bits build

From: Segher Boessenkool
Date: Tue Dec 21 2021 - 14:41:58 EST


On Tue, Dec 21, 2021 at 05:49:33PM +0000, Christophe Leroy wrote:
> diff --git a/arch/powerpc/kernel/vdso32/datapage.S b/arch/powerpc/kernel/vdso32/datapage.S
> index 65244416ab94..db8e167f0166 100644
> --- a/arch/powerpc/kernel/vdso32/datapage.S
> +++ b/arch/powerpc/kernel/vdso32/datapage.S
> @@ -30,11 +30,15 @@ V_FUNCTION_BEGIN(__kernel_get_syscall_map)
> mr. r4,r3
> get_datapage r3
> mtlr r12
> +#ifdef __powerpc64__
> + addi r3,r3,CFG_SYSCALL_MAP64
> +#else
> addi r3,r3,CFG_SYSCALL_MAP32
> +#endif
> + crclr cr0*4+so
> beqlr
> li r0,NR_syscalls
> stw r0,0(r4)
> - crclr cr0*4+so
> blr

This now clears cr0.3 if r3 is zero on entry. Is that on purpose?

Rest looks good.

Reviewed-by: Segher Boessenkool <segher@xxxxxxxxxxxxxxxxxxx>


Segher