Re: [PATCH v5 09/22] powerpc/syscall: Make interrupt.c buildable on PPC32

Nicholas Piggin
2021-02-09T07:52:04Z

Excerpts from Christophe Leroy's message of February 9, 2021 4:02 pm:
>
>
> Le 09/02/2021 à 02:27, Nicholas Piggin a écrit :
>> Excerpts from Christophe Leroy's message of February 9, 2021 1:10 am:
>>> To allow building interrupt.c on PPC32, ifdef out specific PPC64
>>> code or use helpers which are available on both PP32 and PPC64
>>>
>>> Modify Makefile to always build interrupt.o
>>>
>>> Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
>>> ---
>>> v5:
>>> - Also for interrupt exit preparation
>>> - Opted out kuap related code, ppc32 keeps it in ASM for the time being
>>> ---
>>> arch/powerpc/kernel/Makefile | 4 ++--
>>> arch/powerpc/kernel/interrupt.c | 31 ++++++++++++++++++++++++-------
>>> 2 files changed, 26 insertions(+), 9 deletions(-)
>>>
>
>>> diff --git a/arch/powerpc/kernel/interrupt.c b/arch/powerpc/kernel/interrupt.c
>>> index d6be4f9a67e5..2dac4d2bb1cf 100644
>>> --- a/arch/powerpc/kernel/interrupt.c
>>> +++ b/arch/powerpc/kernel/interrupt.c
>>> @@ -39,7 +39,7 @@ notrace long system_call_exception(long r3, long r4, long r5,
>>> BUG_ON(!(regs->msr & MSR_RI));
>>> BUG_ON(!(regs->msr & MSR_PR));
>>> BUG_ON(!FULL_REGS(regs));
>>> - BUG_ON(regs->softe != IRQS_ENABLED);
>>> + BUG_ON(arch_irq_disabled_regs(regs));
>>>
>>> #ifdef CONFIG_PPC_PKEY
>>> if (mmu_has_feature(MMU_FTR_PKEY)) {
>>> @@ -65,7 +65,9 @@ notrace long system_call_exception(long r3, long r4, long r5,
>>> isync();
>>> } else
>>> #endif
>>> +#ifdef CONFIG_PPC64
>>> kuap_check_amr();
>>> +#endif
>>
>> Wouldn't mind trying to get rid of these ifdefs at some point, but
>> there's some kuap / keys changes going on recently so I'm happy enough
>> to let this settle then look at whether we can refactor.
>
> I have a follow up series that implements interrupts entries/exits in C and that removes all kuap
> assembly, I will likely release it as RFC later today.
>
>>
>>>
>>> account_cpu_user_entry();
>>>
>>> @@ -318,7 +323,7 @@ notrace unsigned long syscall_exit_prepare(unsigned long r3,
>>> return ret;
>>> }
>>>
>>> -#ifdef CONFIG_PPC_BOOK3S /* BOOK3E not yet using this */
>>> +#ifndef CONFIG_PPC_BOOK3E_64 /* BOOK3E not yet using this */
>>> notrace unsigned long interrupt_exit_user_prepare(struct pt_regs *regs, unsigned long msr)
>>> {
>>> #ifdef CONFIG_PPC_BOOK3E
>>
>> Why are you building this for 32? I don't mind if it's just to keep
>> things similar and make it build for now, but you're not using it yet,
>> right?
>
> The series using that will follow, I thought it would be worth doing this at once.

Yeah that's fine by me then.

Thanks,
Nick