Re: [PATCH] powerpc: Fix sstep compile on powerpcspe

[Lennart Sorensen]

On Thu, May 05, 2016 at 04:44:44PM -0400, Lennart Sorensen wrote:
> powerpc: Fix sstep compile on powerpcspe
> 
> Commit be96f63375a14ee8e690856ac77e579c75bd0bae introduced ldarx and stdcx
> into the instructions in sstep.c, which are not accepted by the assembler
> on powerpcspe, but does seem to be accepted by the normal powerpc assembler
> even in 32 bit mode.
> 
> Wrap these two instructions in a __powerpc64__ check like it is everywhere
> else in the file.
> 
> Fixes: be96f63375a1 ("powerpc: Split out instruction analysis part of emulate_step()")
> Signed-off-by: Len Sorensen <lsorense@xxxxxxxxxxxxxxxxxxx>
> ---
>  arch/powerpc/lib/sstep.c |    4 ++++
>  1 file changed, 4 insertions(+)
> 
> diff --git a/arch/powerpc/lib/sstep.c b/arch/powerpc/lib/sstep.c
> index dc885b3..6d34310 100644
> --- a/arch/powerpc/lib/sstep.c
> +++ b/arch/powerpc/lib/sstep.c
> @@ -1818,9 +1818,11 @@ int __kprobes emulate_step(struct pt_regs *regs, unsigned int instr)
>  		case 4:
>  			__get_user_asmx(val, op.ea, err, "lwarx");
>  			break;
> +#ifdef __powerpc64__
>  		case 8:
>  			__get_user_asmx(val, op.ea, err, "ldarx");
>  			break;
> +#endif
>  		default:
>  			return 0;
>  		}
> @@ -1841,9 +1843,11 @@ int __kprobes emulate_step(struct pt_regs *regs, unsigned int instr)
>  		case 4:
>  			__put_user_asmx(op.val, op.ea, err, "stwcx.", cr);
>  			break;
> +#ifdef __powerpc64__
>  		case 8:
>  			__put_user_asmx(op.val, op.ea, err, "stdcx.", cr);
>  			break;
> +#endif
>  		default:
>  			return 0;
>  		}
> -- 
> 1.7.10.4

Perhaps this should be considered for -stable as well since it is fixing
a regression for powerpcspe.

-- 
Len Sorensen