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

Christophe Leroy
2021-02-09T06:03:26Z

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.

>
> Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
>