Re: KUEP broken on FSP2?

[Eddie James <eajames@linux.ibm.com>]

On 10/9/23 08:14, Michael Ellerman wrote:
> Eddie James <eajames@linux.ibm.com> writes:
>> Hi,
>>
>> I'm attempting to run linux 6.1 on my FSP2, but my kernel crashes
>> attempting to get into userspace. The init script works, but the first
>> binary (mount) I run results in oops. Can anyone help me to debug this
>> further or suggest anything?
> Hi Eddie,
>
> It looks like breakage in syscall_exit_finish.
> Can you test this? Patch is against v6.1.


That worked! Perfect. Thank you very much! Will you send it upstream?


Thanks,

Eddie


>
> cheers
>
>
> diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S
> index 3fc7c9886bb7..decd2594fb9c 100644
> --- a/arch/powerpc/kernel/entry_32.S
> +++ b/arch/powerpc/kernel/entry_32.S
> @@ -135,7 +135,8 @@ ret_from_syscall:
>   	lis	r4,icache_44x_need_flush@ha
>   	lwz	r5,icache_44x_need_flush@l(r4)
>   	cmplwi	cr0,r5,0
> -	bne-	2f
> +	bne-	.L44x_icache_flush
> +.L44x_icache_flush_return:
>   #endif /* CONFIG_PPC_47x */
>   	kuep_unlock
>   	lwz	r4,_LINK(r1)
> @@ -170,10 +171,11 @@ syscall_exit_finish:
>   	b	1b
>   
>   #ifdef CONFIG_44x
> -2:	li	r7,0
> +.L44x_icache_flush:
> +	li	r7,0
>   	iccci	r0,r0
>   	stw	r7,icache_44x_need_flush@l(r4)
> -	b	1b
> +	b	.L44x_icache_flush_return
>   #endif  /* CONFIG_44x */
>   
>   	.globl	ret_from_fork