[PATCH] powerpc: Wire up clone3 syscall

[Christian Brauner]

On Wed, Jul 24, 2019 at 12:25:14PM +0700, Arseny Solokha wrote:
> Hi,
> 
> may I also ask to provide ppc_clone3 symbol also for 32-bit powerpc? Otherwise
> Michael's patch breaks build for me:

Makes sense. Michael, are you planning on picking this up? :)

Christian

> 
>   powerpc-e500v2-linux-gnuspe-ld: arch/powerpc/kernel/systbl.o: in function `sys_call_table':
>   (.rodata+0x6cc): undefined reference to `ppc_clone3'
>   make: *** [Makefile:1060: vmlinux] Error 1
> 
> The patch was tested using Christian's program on a real e500 machine.
> 
> --- a/arch/powerpc/kernel/entry_32.S
> +++ b/arch/powerpc/kernel/entry_32.S
> @@ -597,6 +597,14 @@ ppc_clone:
>  	stw	r0,_TRAP(r1)		/* register set saved */
>  	b	sys_clone
> 
> +	.globl	ppc_clone3
> +ppc_clone3:
> +	SAVE_NVGPRS(r1)
> +	lwz	r0,_TRAP(r1)
> +	rlwinm	r0,r0,0,0,30		/* clear LSB to indicate full */
> +	stw	r0,_TRAP(r1)		/* register set saved */
> +	b	sys_clone3
> +
>  	.globl	ppc_swapcontext
>  ppc_swapcontext:
>  	SAVE_NVGPRS(r1)
> 
> I don't think this trivial hunk deserves a separate patch submission.
> 
> Thanks,
> Arseny