Excerpts from Christophe Leroy's message of January 14, 2021 12:45 am:
>
>
> Le 13/01/2021 à 08:32, Nicholas Piggin a écrit :
>> Add wrapper functions (derived from x86 macros) for interrupt handler
>> functions. This allows interrupt entry code to be written in C.
>
> Looks like you are doing more than just that is this patch. WOuld be worth
> splitting in several
> patches I think,
>
> I'd suggest:
> - Other patches for unrelated changes, see below for details
> - One patch that brings the wrapper macros
> - One patch that uses those macros
>
>>
>> Signed-off-by: Nicholas Piggin <npig...@gmail.com>
>> ---
>> arch/powerpc/include/asm/asm-prototypes.h | 29 ---
>> arch/powerpc/include/asm/book3s/64/mmu-hash.h | 1 -
>> arch/powerpc/include/asm/hw_irq.h | 9 -
>> arch/powerpc/include/asm/interrupt.h | 218 ++++++++++++++++++
>> arch/powerpc/include/asm/time.h | 2 +
>> arch/powerpc/kernel/dbell.c | 12 +-
>> arch/powerpc/kernel/exceptions-64s.S | 7 +-
>> arch/powerpc/kernel/head_book3s_32.S | 6 +-
>> arch/powerpc/kernel/irq.c | 3 +-
>> arch/powerpc/kernel/mce.c | 5 +-
>> arch/powerpc/kernel/syscall_64.c | 1 +
>> arch/powerpc/kernel/tau_6xx.c | 2 +-
>> arch/powerpc/kernel/time.c | 3 +-
>> arch/powerpc/kernel/traps.c | 90 +++++---
>> arch/powerpc/kernel/watchdog.c | 7 +-
>> arch/powerpc/kvm/book3s_hv.c | 1 +
>> arch/powerpc/kvm/book3s_hv_builtin.c | 1 +
>> arch/powerpc/kvm/booke.c | 1 +
>> arch/powerpc/mm/book3s64/hash_utils.c | 57 +++--
>> arch/powerpc/mm/book3s64/slb.c | 29 +--
>> arch/powerpc/mm/fault.c | 15 +-
>> arch/powerpc/platforms/powernv/idle.c | 1 +
>> 22 files changed, 374 insertions(+), 126 deletions(-)
>> create mode 100644 arch/powerpc/include/asm/interrupt.h
>>
>
> ...
>
>> diff --git a/arch/powerpc/include/asm/interrupt.h
>> b/arch/powerpc/include/asm/interrupt.h
>> new file mode 100644
>> index 000000000000..60363e5eeffa
>> --- /dev/null
>> +++ b/arch/powerpc/include/asm/interrupt.h
>
> ...
>
>> +/* Interrupt handlers */
>> +DECLARE_INTERRUPT_HANDLER_NMI(machine_check_early);
>> +DECLARE_INTERRUPT_HANDLER_NMI(hmi_exception_realmode);
>> +DECLARE_INTERRUPT_HANDLER(SMIException);
>> +DECLARE_INTERRUPT_HANDLER(handle_hmi_exception);
>> +DECLARE_INTERRUPT_HANDLER(instruction_breakpoint_exception);
>> +DECLARE_INTERRUPT_HANDLER(RunModeException);
>> +DECLARE_INTERRUPT_HANDLER(single_step_exception);
>> +DECLARE_INTERRUPT_HANDLER(program_check_exception);
>> +DECLARE_INTERRUPT_HANDLER(alignment_exception);
>> +DECLARE_INTERRUPT_HANDLER(StackOverflow);
>> +DECLARE_INTERRUPT_HANDLER(stack_overflow_exception);
>> +DECLARE_INTERRUPT_HANDLER(kernel_fp_unavailable_exception);
>> +DECLARE_INTERRUPT_HANDLER(altivec_unavailable_exception);
>> +DECLARE_INTERRUPT_HANDLER(vsx_unavailable_exception);
>> +DECLARE_INTERRUPT_HANDLER(fp_unavailable_tm);
>> +DECLARE_INTERRUPT_HANDLER(altivec_unavailable_tm);
>> +DECLARE_INTERRUPT_HANDLER(vsx_unavailable_tm);
>> +DECLARE_INTERRUPT_HANDLER(facility_unavailable_exception);
>> +DECLARE_INTERRUPT_HANDLER_ASYNC(TAUException);
>> +DECLARE_INTERRUPT_HANDLER(altivec_assist_exception);
>> +DECLARE_INTERRUPT_HANDLER(unrecoverable_exception);
>> +DECLARE_INTERRUPT_HANDLER(kernel_bad_stack);
>> +DECLARE_INTERRUPT_HANDLER_NMI(system_reset_exception);
>> +#ifdef CONFIG_PPC_BOOK3S_64
>> +DECLARE_INTERRUPT_HANDLER_ASYNC(machine_check_exception);
>> +#else
>> +DECLARE_INTERRUPT_HANDLER_NMI(machine_check_exception);
>> +#endif
>> +DECLARE_INTERRUPT_HANDLER(emulation_assist_interrupt);
>> +DECLARE_INTERRUPT_HANDLER_RAW(do_slb_fault);
>> +DECLARE_INTERRUPT_HANDLER(do_bad_slb_fault);
>> +DECLARE_INTERRUPT_HANDLER_RAW(do_hash_fault);
>> +DECLARE_INTERRUPT_HANDLER_RET(do_page_fault);
>> +DECLARE_INTERRUPT_HANDLER(__do_bad_page_fault);
>> +DECLARE_INTERRUPT_HANDLER(do_bad_page_fault);
>
> Missing DECLARE_INTERRUPT_HANDLER(do_break)
>
>> +
>> +DECLARE_INTERRUPT_HANDLER_ASYNC(timer_interrupt);
>> +DECLARE_INTERRUPT_HANDLER_NMI(performance_monitor_exception_nmi);
>> +DECLARE_INTERRUPT_HANDLER_ASYNC(performance_monitor_exception_async);
>> +DECLARE_INTERRUPT_HANDLER_RAW(performance_monitor_exception);
>> +DECLARE_INTERRUPT_HANDLER(WatchdogException);
>> +DECLARE_INTERRUPT_HANDLER(unknown_exception);
>> +DECLARE_INTERRUPT_HANDLER_ASYNC(unknown_async_exception);
>> +
>> +void replay_system_reset(void);
>> +void replay_soft_interrupts(void);
>> +
>> +#endif /* _ASM_POWERPC_INTERRUPT_H */
>> diff --git a/arch/powerpc/include/asm/time.h
>> b/arch/powerpc/include/asm/time.h
>> index 8f789b597bae..8dd3cdb25338 100644
>> --- a/arch/powerpc/include/asm/time.h
>> +++ b/arch/powerpc/include/asm/time.h
>> @@ -102,6 +102,8 @@ DECLARE_PER_CPU(u64, decrementers_next_tb);
>> /* Convert timebase ticks to nanoseconds */
>> unsigned long long tb_to_ns(unsigned long long tb_ticks);
>>
>> +void timer_broadcast_interrupt(void);
>
> This seems unrelated. I think a separate patch woud be better for moving
> prototypes without making
> them wrappers.
Yeah this might have just slipped in, thanks.
>> +
>> /* SPLPAR */
>> void accumulate_stolen_time(void);
>>
>> diff --git a/arch/powerpc/kernel/dbell.c b/arch/powerpc/kernel/dbell.c
>> index 52680cf07c9d..c0f99f8ffa7d 100644
>> --- a/arch/powerpc/kernel/dbell.c
>> +++ b/arch/powerpc/kernel/dbell.c
>> @@ -12,14 +12,14 @@
>> #include <linux/hardirq.h>
>>
>> #include <asm/dbell.h>
>> +#include <asm/interrupt.h>
>> #include <asm/irq_regs.h>
>> #include <asm/kvm_ppc.h>
>> #include <asm/trace.h>
>>
>> -#ifdef CONFIG_SMP
>> -
>
> This seems unrelated, is that needed ? What's the problem with having to full
> versions of
> doorbell_exception() ?
No real problem I think, it might have been from some earlier work in
progress. I can adjust it.
>
>> -void doorbell_exception(struct pt_regs *regs)
>> +DEFINE_INTERRUPT_HANDLER_ASYNC(doorbell_exception)
>> {
>> +#ifdef CONFIG_SMP
>> struct pt_regs *old_regs = set_irq_regs(regs);
>>
>> irq_enter();
>> @@ -37,11 +37,7 @@ void doorbell_exception(struct pt_regs *regs)
>> trace_doorbell_exit(regs);
>> irq_exit();
>> set_irq_regs(old_regs);
>> -}
>> #else /* CONFIG_SMP */
>> -void doorbell_exception(struct pt_regs *regs)
>> -{
>> printk(KERN_WARNING "Received doorbell on non-smp system\n");
>> -}
>> #endif /* CONFIG_SMP */
>> -
>> +}
>> diff --git a/arch/powerpc/kernel/exceptions-64s.S
>> b/arch/powerpc/kernel/exceptions-64s.S
>> index 36dea2020ec5..8b0db807974c 100644
>> --- a/arch/powerpc/kernel/exceptions-64s.S
>> +++ b/arch/powerpc/kernel/exceptions-64s.S
>> @@ -1923,7 +1923,7 @@ EXC_COMMON_BEGIN(doorbell_super_common)
>> #ifdef CONFIG_PPC_DOORBELL
>> bl doorbell_exception
>> #else
>> - bl unknown_exception
>> + bl unknown_async_exception
>
> Unrelated to wrappers ?
Well there's now a difference between sync and async exceptions, but it
could be introduced in a different patch.
>> #endif
>> b interrupt_return
>>
>> @@ -2136,8 +2136,7 @@ EXC_COMMON_BEGIN(h_data_storage_common)
>> GEN_COMMON h_data_storage
>> addi r3,r1,STACK_FRAME_OVERHEAD
>> BEGIN_MMU_FTR_SECTION
>> - li r4,SIGSEGV
>> - bl bad_page_fault
>> + bl do_bad_page_fault
>
> Is this name change related ?
The do_ variant is a "handler", the other can be called from C.
>> MMU_FTR_SECTION_ELSE
>> bl unknown_exception
>> ALT_MMU_FTR_SECTION_END_IFSET(MMU_FTR_TYPE_RADIX)
>> @@ -2310,7 +2309,7 @@ EXC_COMMON_BEGIN(h_doorbell_common)
>> #ifdef CONFIG_PPC_DOORBELL
>> bl doorbell_exception
>> #else
>> - bl unknown_exception
>> + bl unknown_async_exception
>> #endif
>> b interrupt_return
>>
>> diff --git a/arch/powerpc/kernel/head_book3s_32.S
>> b/arch/powerpc/kernel/head_book3s_32.S
>> index 94ad1372c490..9b4d5432e2db 100644
>> --- a/arch/powerpc/kernel/head_book3s_32.S
>> +++ b/arch/powerpc/kernel/head_book3s_32.S
>> @@ -238,8 +238,8 @@ __secondary_hold_acknowledge:
>>
>> /* System reset */
>> /* core99 pmac starts the seconary here by changing the vector, and
>> - putting it back to what it was (unknown_exception) when done. */
>> - EXCEPTION(0x100, Reset, unknown_exception, EXC_XFER_STD)
>> + putting it back to what it was (unknown_async_exception) when done. */
>> + EXCEPTION(0x100, Reset, unknown_async_exception, EXC_XFER_STD)
>>
>> /* Machine check */
>> /*
>> @@ -631,7 +631,7 @@ END_MMU_FTR_SECTION_IFSET(MMU_FTR_NEED_DTLB_SW_LRU)
>> #endif
>>
>> #ifndef CONFIG_TAU_INT
>> -#define TAUException unknown_exception
>> +#define TAUException unknown_async_exception
>> #endif
>>
>> EXCEPTION(0x1300, Trap_13, instruction_breakpoint_exception,
>> EXC_XFER_STD)
>> diff --git a/arch/powerpc/kernel/irq.c b/arch/powerpc/kernel/irq.c
>> index 6b1eca53e36c..2055d204d08e 100644
>> --- a/arch/powerpc/kernel/irq.c
>> +++ b/arch/powerpc/kernel/irq.c
>> @@ -54,6 +54,7 @@
>> #include <linux/pgtable.h>
>>
>> #include <linux/uaccess.h>
>> +#include <asm/interrupt.h>
>> #include <asm/io.h>
>> #include <asm/irq.h>
>> #include <asm/cache.h>
>> @@ -665,7 +666,7 @@ void __do_irq(struct pt_regs *regs)
>> irq_exit();
>> }
>>
>> -void do_IRQ(struct pt_regs *regs)
>> +DEFINE_INTERRUPT_HANDLER_ASYNC(do_IRQ)
>> {
>> struct pt_regs *old_regs = set_irq_regs(regs);
>> void *cursp, *irqsp, *sirqsp;
>> diff --git a/arch/powerpc/kernel/mce.c b/arch/powerpc/kernel/mce.c
>> index 9f3e133b57b7..54269947113d 100644
>> --- a/arch/powerpc/kernel/mce.c
>> +++ b/arch/powerpc/kernel/mce.c
>> @@ -18,6 +18,7 @@
>> #include <linux/extable.h>
>> #include <linux/ftrace.h>
>>
>> +#include <asm/interrupt.h>
>> #include <asm/machdep.h>
>> #include <asm/mce.h>
>> #include <asm/nmi.h>
>> @@ -588,7 +589,7 @@ EXPORT_SYMBOL_GPL(machine_check_print_event_info);
>> *
>> * regs->nip and regs->msr contains srr0 and ssr1.
>> */
>> -long notrace machine_check_early(struct pt_regs *regs)
>> +DEFINE_INTERRUPT_HANDLER_NMI(machine_check_early)
>> {
>> long handled = 0;
>> u8 ftrace_enabled = this_cpu_get_ftrace_enabled();
>> @@ -722,7 +723,7 @@ long hmi_handle_debugtrig(struct pt_regs *regs)
>> /*
>> * Return values:
>> */
>> -long hmi_exception_realmode(struct pt_regs *regs)
>> +DEFINE_INTERRUPT_HANDLER_NMI(hmi_exception_realmode)
>> {
>> int ret;
>>
>> diff --git a/arch/powerpc/kernel/syscall_64.c
>> b/arch/powerpc/kernel/syscall_64.c
>> index 7c85ed04a164..dd87b2118620 100644
>> --- a/arch/powerpc/kernel/syscall_64.c
>> +++ b/arch/powerpc/kernel/syscall_64.c
>> @@ -5,6 +5,7 @@
>> #include <asm/kup.h>
>> #include <asm/cputime.h>
>> #include <asm/hw_irq.h>
>> +#include <asm/interrupt.h>
>> #include <asm/kprobes.h>
>> #include <asm/paca.h>
>> #include <asm/ptrace.h>
>> diff --git a/arch/powerpc/kernel/tau_6xx.c b/arch/powerpc/kernel/tau_6xx.c
>> index 0b4694b8d248..46b2e5de4ef5 100644
>> --- a/arch/powerpc/kernel/tau_6xx.c
>> +++ b/arch/powerpc/kernel/tau_6xx.c
>> @@ -100,7 +100,7 @@ static void TAUupdate(int cpu)
>> * with interrupts disabled
>> */
>>
>> -void TAUException(struct pt_regs * regs)
>> +DEFINE_INTERRUPT_HANDLER_ASYNC(TAUException)
>> {
>> int cpu = smp_processor_id();
>>
>> diff --git a/arch/powerpc/kernel/time.c b/arch/powerpc/kernel/time.c
>> index 67feb3524460..435a251247ed 100644
>> --- a/arch/powerpc/kernel/time.c
>> +++ b/arch/powerpc/kernel/time.c
>> @@ -56,6 +56,7 @@
>> #include <linux/processor.h>
>> #include <asm/trace.h>
>>
>> +#include <asm/interrupt.h>
>> #include <asm/io.h>
>> #include <asm/nvram.h>
>> #include <asm/cache.h>
>> @@ -570,7 +571,7 @@ void arch_irq_work_raise(void)
>> * timer_interrupt - gets called when the decrementer overflows,
>> * with interrupts disabled.
>> */
>> -void timer_interrupt(struct pt_regs *regs)
>> +DEFINE_INTERRUPT_HANDLER_ASYNC(timer_interrupt)
>> {
>> struct clock_event_device *evt = this_cpu_ptr(&decrementers);
>> u64 *next_tb = this_cpu_ptr(&decrementers_next_tb);
>> diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c
>> index 9b5298c016c7..f4462b481248 100644
>> --- a/arch/powerpc/kernel/traps.c
>> +++ b/arch/powerpc/kernel/traps.c
>> @@ -41,6 +41,7 @@
>> #include <asm/emulated_ops.h>
>> #include <linux/uaccess.h>
>> #include <asm/debugfs.h>
>> +#include <asm/interrupt.h>
>> #include <asm/io.h>
>> #include <asm/machdep.h>
>> #include <asm/rtas.h>
>> @@ -430,8 +431,7 @@ void hv_nmi_check_nonrecoverable(struct pt_regs *regs)
>> regs->msr &= ~MSR_RI;
>> #endif
>> }
>> -
>> -void system_reset_exception(struct pt_regs *regs)
>> +DEFINE_INTERRUPT_HANDLER_NMI(system_reset_exception)
>> {
>> unsigned long hsrr0, hsrr1;
>> bool saved_hsrrs = false;
>> @@ -516,7 +516,10 @@ void system_reset_exception(struct pt_regs *regs)
>> this_cpu_set_ftrace_enabled(ftrace_enabled);
>>
>> /* What should we do here? We could issue a shutdown or hard reset. */
>> +
>> + return 0;
>> }
>> +NOKPROBE_SYMBOL(system_reset_exception);
>
> Is this NOKPROBE_SYMBOL() related to wrappers or just a bug fix ?
Hmm, I don't remember off the top of my head now, may be bug fix but
I don't know why we haven't seen it already. I have tested MCE with
tracing I thought but maybe not carefully enough.
I will move them to another patch.
>
>>
>> /*
>> * I/O accesses can cause machine checks on powermacs.
>> @@ -788,7 +791,12 @@ int machine_check_generic(struct pt_regs *regs)
>> }
>> #endif /* everything else */
>>
>> -void machine_check_exception(struct pt_regs *regs)
>> +
>> +#ifdef CONFIG_PPC_BOOK3S_64
>> +DEFINE_INTERRUPT_HANDLER_ASYNC(machine_check_exception)
>> +#else
>> +DEFINE_INTERRUPT_HANDLER_NMI(machine_check_exception)
>> +#endif
>> {
>> int recover = 0;
>>
>> @@ -838,13 +846,21 @@ void machine_check_exception(struct pt_regs *regs)
>> if (!(regs->msr & MSR_RI))
>> die("Unrecoverable Machine check", regs, SIGBUS);
>>
>> +#ifdef CONFIG_PPC_BOOK3S_64
>> +bail:
>> return;
>> +#else
>> + return 0;
>>
>> bail:
>> if (nmi) nmi_exit();
>> +
>> + return 0;
>> +#endif
>
> Looks fishy. Can't we have both returning either long or void ?
All handlers could return long, then you would have lots of pointless
`return 0` and `li r3,0`. HMI exception NMI wants to return something.
Arguably HMI should handle local_irq_disable with irq_work, like MCE
does. I have noted that in the HMI interrupt comment and will get to
it eventually, which should unify this.
>
>> }
>> +NOKPROBE_SYMBOL(machine_check_exception);
>
> Is this NOKPROBE_SYMBOL() related to wrappers or just a bug fix ?
>
>>
>> -void SMIException(struct pt_regs *regs)
>> +DEFINE_INTERRUPT_HANDLER(SMIException) /* async? */
>> {
>> die("System Management Interrupt", regs, SIGABRT);
>> }
>> @@ -1030,7 +1046,7 @@ static void p9_hmi_special_emu(struct pt_regs *regs)
>> }
>> #endif /* CONFIG_VSX */
>>
>> -void handle_hmi_exception(struct pt_regs *regs)
>> +DEFINE_INTERRUPT_HANDLER_ASYNC(handle_hmi_exception)
>> {
>> struct pt_regs *old_regs;
>>
>> @@ -1059,7 +1075,7 @@ void handle_hmi_exception(struct pt_regs *regs)
>> set_irq_regs(old_regs);
>> }
>>
>> -void unknown_exception(struct pt_regs *regs)
>> +DEFINE_INTERRUPT_HANDLER(unknown_exception)
>> {
>> enum ctx_state prev_state = exception_enter();
>>
>> @@ -1071,7 +1087,19 @@ void unknown_exception(struct pt_regs *regs)
>> exception_exit(prev_state);
>> }
>>
>> -void instruction_breakpoint_exception(struct pt_regs *regs)
>
> shouldn't unknown_async_exception() be added in a preceeding patch ?
+1
>> +DEFINE_INTERRUPT_HANDLER_ASYNC(unknown_async_exception)
>> +{
>> + enum ctx_state prev_state = exception_enter();
>> +
>> + printk("Bad trap at PC: %lx, SR: %lx, vector=%lx\n",
>> + regs->nip, regs->msr, regs->trap);
>> +
>> + _exception(SIGTRAP, regs, TRAP_UNK, 0);
>> +
>> + exception_exit(prev_state);
>> +}
>> +
>> +DEFINE_INTERRUPT_HANDLER(instruction_breakpoint_exception)
>> {
>> enum ctx_state prev_state = exception_enter();
>>
>> @@ -1086,12 +1114,12 @@ void instruction_breakpoint_exception(struct pt_regs
>> *regs)
>> exception_exit(prev_state);
>> }
>>
>> -void RunModeException(struct pt_regs *regs)
>> +DEFINE_INTERRUPT_HANDLER(RunModeException)
>> {
>> _exception(SIGTRAP, regs, TRAP_UNK, 0);
>> }
>>
>> -void single_step_exception(struct pt_regs *regs)
>> +DEFINE_INTERRUPT_HANDLER(single_step_exception)
>> {
>> enum ctx_state prev_state = exception_enter();
>>
>> @@ -1436,7 +1464,7 @@ static int emulate_math(struct pt_regs *regs)
>> static inline int emulate_math(struct pt_regs *regs) { return -1; }
>> #endif
>>
>> -void program_check_exception(struct pt_regs *regs)
>> +DEFINE_INTERRUPT_HANDLER(program_check_exception)
>> {
>> enum ctx_state prev_state = exception_enter();
>> unsigned int reason = get_reason(regs);
>> @@ -1561,14 +1589,14 @@ NOKPROBE_SYMBOL(program_check_exception);
>> * This occurs when running in hypervisor mode on POWER6 or later
>> * and an illegal instruction is encountered.
>> */
>> -void emulation_assist_interrupt(struct pt_regs *regs)
>> +DEFINE_INTERRUPT_HANDLER(emulation_assist_interrupt)
>> {
>> regs->msr |= REASON_ILLEGAL;
>> program_check_exception(regs);
>> }
>> NOKPROBE_SYMBOL(emulation_assist_interrupt);
>>
>> -void alignment_exception(struct pt_regs *regs)
>> +DEFINE_INTERRUPT_HANDLER(alignment_exception)
>> {
>> enum ctx_state prev_state = exception_enter();
>> int sig, code, fixed = 0;
>> @@ -1618,7 +1646,7 @@ void alignment_exception(struct pt_regs *regs)
>> exception_exit(prev_state);
>> }
>>
>> -void StackOverflow(struct pt_regs *regs)
>> +DEFINE_INTERRUPT_HANDLER(StackOverflow)
>> {
>> pr_crit("Kernel stack overflow in process %s[%d], r1=%lx\n",
>> current->comm, task_pid_nr(current), regs->gpr[1]);
>> @@ -1627,7 +1655,7 @@ void StackOverflow(struct pt_regs *regs)
>> panic("kernel stack overflow");
>> }
>>
>> -void stack_overflow_exception(struct pt_regs *regs)
>> +DEFINE_INTERRUPT_HANDLER(stack_overflow_exception)
>> {
>> enum ctx_state prev_state = exception_enter();
>>
>> @@ -1636,7 +1664,7 @@ void stack_overflow_exception(struct pt_regs *regs)
>> exception_exit(prev_state);
>> }
>>
>> -void kernel_fp_unavailable_exception(struct pt_regs *regs)
>> +DEFINE_INTERRUPT_HANDLER(kernel_fp_unavailable_exception)
>> {
>> enum ctx_state prev_state = exception_enter();
>>
>> @@ -1647,7 +1675,7 @@ void kernel_fp_unavailable_exception(struct pt_regs
>> *regs)
>> exception_exit(prev_state);
>> }
>>
>> -void altivec_unavailable_exception(struct pt_regs *regs)
>> +DEFINE_INTERRUPT_HANDLER(altivec_unavailable_exception)
>> {
>> enum ctx_state prev_state = exception_enter();
>>
>> @@ -1666,7 +1694,7 @@ void altivec_unavailable_exception(struct pt_regs
>> *regs)
>> exception_exit(prev_state);
>> }
>>
>> -void vsx_unavailable_exception(struct pt_regs *regs)
>> +DEFINE_INTERRUPT_HANDLER(vsx_unavailable_exception)
>> {
>> if (user_mode(regs)) {
>> /* A user program has executed an vsx instruction,
>> @@ -1697,7 +1725,7 @@ static void tm_unavailable(struct pt_regs *regs)
>> die("Unrecoverable TM Unavailable Exception", regs, SIGABRT);
>> }
>>
>> -void facility_unavailable_exception(struct pt_regs *regs)
>> +DEFINE_INTERRUPT_HANDLER(facility_unavailable_exception)
>> {
>> static char *facility_strings[] = {
>> [FSCR_FP_LG] = "FPU",
>> @@ -1817,7 +1845,7 @@ void facility_unavailable_exception(struct pt_regs
>> *regs)
>>
>> #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
>>
>> -void fp_unavailable_tm(struct pt_regs *regs)
>> +DEFINE_INTERRUPT_HANDLER(fp_unavailable_tm)
>> {
>> /* Note: This does not handle any kind of FP laziness. */
>>
>> @@ -1850,7 +1878,7 @@ void fp_unavailable_tm(struct pt_regs *regs)
>> tm_recheckpoint(¤t->thread);
>> }
>>
>> -void altivec_unavailable_tm(struct pt_regs *regs)
>> +DEFINE_INTERRUPT_HANDLER(altivec_unavailable_tm)
>> {
>> /* See the comments in fp_unavailable_tm(). This function operates
>> * the same way.
>> @@ -1865,7 +1893,7 @@ void altivec_unavailable_tm(struct pt_regs *regs)
>> current->thread.used_vr = 1;
>> }
>>
>> -void vsx_unavailable_tm(struct pt_regs *regs)
>> +DEFINE_INTERRUPT_HANDLER(vsx_unavailable_tm)
>> {
>> /* See the comments in fp_unavailable_tm(). This works similarly,
>> * though we're loading both FP and VEC registers in here.
>> @@ -1890,7 +1918,8 @@ void vsx_unavailable_tm(struct pt_regs *regs)
>> }
>> #endif /* CONFIG_PPC_TRANSACTIONAL_MEM */
>>
>> -static void performance_monitor_exception_nmi(struct pt_regs *regs)
>> +#ifdef CONFIG_PPC64
>> +DEFINE_INTERRUPT_HANDLER_NMI(performance_monitor_exception_nmi)
>> {
>> nmi_enter();
>>
>> @@ -1899,9 +1928,12 @@ static void performance_monitor_exception_nmi(struct
>> pt_regs *regs)
>> perf_irq(regs);
>>
>> nmi_exit();
>> +
>> + return 0;
>> }
>> +#endif
>>
>> -static void performance_monitor_exception_async(struct pt_regs *regs)
>> +DEFINE_INTERRUPT_HANDLER_ASYNC(performance_monitor_exception_async)
>> {
>> irq_enter();
>>
>> @@ -1912,7 +1944,7 @@ static void performance_monitor_exception_async(struct
>> pt_regs *regs)
>> irq_exit();
>> }
>>
>> -void performance_monitor_exception(struct pt_regs *regs)
>> +DEFINE_INTERRUPT_HANDLER_RAW(performance_monitor_exception)
>> {
>> /*
>> * On 64-bit, if perf interrupts hit in a local_irq_disable
>> @@ -1924,6 +1956,8 @@ void performance_monitor_exception(struct pt_regs
>> *regs)
>> performance_monitor_exception_nmi(regs);
>> else
>> performance_monitor_exception_async(regs);
>> +
>> + return 0;
>> }
>>
>> #ifdef CONFIG_PPC_ADV_DEBUG_REGS
>> @@ -2057,7 +2091,7 @@ NOKPROBE_SYMBOL(DebugException);
>> #endif /* CONFIG_PPC_ADV_DEBUG_REGS */
>>
>> #ifdef CONFIG_ALTIVEC
>> -void altivec_assist_exception(struct pt_regs *regs)
>> +DEFINE_INTERRUPT_HANDLER(altivec_assist_exception)
>> {
>> int err;
>>
>> @@ -2199,7 +2233,7 @@ void SPEFloatingPointRoundException(struct pt_regs
>> *regs)
>> * in the MSR is 0. This indicates that SRR0/1 are live, and that
>> * we therefore lost state by taking this exception.
>> */
>> -void unrecoverable_exception(struct pt_regs *regs)
>> +DEFINE_INTERRUPT_HANDLER(unrecoverable_exception)
>> {
>> pr_emerg("Unrecoverable exception %lx at %lx (msr=%lx)\n",
>> regs->trap, regs->nip, regs->msr);
>> @@ -2219,7 +2253,7 @@ void __attribute__ ((weak)) WatchdogHandler(struct
>> pt_regs *regs)
>> return;
>> }
>>
>> -void WatchdogException(struct pt_regs *regs)
>> +DEFINE_INTERRUPT_HANDLER(WatchdogException) /* XXX NMI? async? */
>> {
>> printk (KERN_EMERG "PowerPC Book-E Watchdog Exception\n");
>> WatchdogHandler(regs);
>> @@ -2230,7 +2264,7 @@ void WatchdogException(struct pt_regs *regs)
>> * We enter here if we discover during exception entry that we are
>> * running in supervisor mode with a userspace value in the stack pointer.
>> */
>> -void kernel_bad_stack(struct pt_regs *regs)
>> +DEFINE_INTERRUPT_HANDLER(kernel_bad_stack)
>> {
>> printk(KERN_EMERG "Bad kernel stack pointer %lx at %lx\n",
>> regs->gpr[1], regs->nip);
>> diff --git a/arch/powerpc/kernel/watchdog.c b/arch/powerpc/kernel/watchdog.c
>> index af3c15a1d41e..824b9376ac35 100644
>> --- a/arch/powerpc/kernel/watchdog.c
>> +++ b/arch/powerpc/kernel/watchdog.c
>> @@ -26,6 +26,7 @@
>> #include <linux/delay.h>
>> #include <linux/smp.h>
>>
>> +#include <asm/interrupt.h>
>> #include <asm/paca.h>
>>
>> /*
>> @@ -247,14 +248,14 @@ static void watchdog_timer_interrupt(int cpu)
>> watchdog_smp_panic(cpu, tb);
>> }
>>
>> -void soft_nmi_interrupt(struct pt_regs *regs)
>> +DEFINE_INTERRUPT_HANDLER_NMI(soft_nmi_interrupt)
>> {
>> unsigned long flags;
>> int cpu = raw_smp_processor_id();
>> u64 tb;
>>
>> if (!cpumask_test_cpu(cpu, &wd_cpus_enabled))
>> - return;
>> + return 0;
>>
>> nmi_enter();
>>
>> @@ -291,6 +292,8 @@ void soft_nmi_interrupt(struct pt_regs *regs)
>>
>> out:
>> nmi_exit();
>> +
>> + return 0;
>> }
>>
>> static enum hrtimer_restart watchdog_timer_fn(struct hrtimer *hrtimer)
>> diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
>> index 6f612d240392..3f9a229f82a2 100644
>> --- a/arch/powerpc/kvm/book3s_hv.c
>> +++ b/arch/powerpc/kvm/book3s_hv.c
>> @@ -53,6 +53,7 @@
>> #include <asm/cputable.h>
>> #include <asm/cacheflush.h>
>> #include <linux/uaccess.h>
>> +#include <asm/interrupt.h>
>> #include <asm/io.h>
>> #include <asm/kvm_ppc.h>
>> #include <asm/kvm_book3s.h>
>> diff --git a/arch/powerpc/kvm/book3s_hv_builtin.c
>> b/arch/powerpc/kvm/book3s_hv_builtin.c
>> index 8053efdf7ea7..10fc274bea65 100644
>> --- a/arch/powerpc/kvm/book3s_hv_builtin.c
>> +++ b/arch/powerpc/kvm/book3s_hv_builtin.c
>> @@ -17,6 +17,7 @@
>>
>> #include <asm/asm-prototypes.h>
>> #include <asm/cputable.h>
>> +#include <asm/interrupt.h>
>> #include <asm/kvm_ppc.h>
>> #include <asm/kvm_book3s.h>
>> #include <asm/archrandom.h>
>> diff --git a/arch/powerpc/kvm/booke.c b/arch/powerpc/kvm/booke.c
>> index 288a9820ec01..bd2bb73021d8 100644
>> --- a/arch/powerpc/kvm/booke.c
>> +++ b/arch/powerpc/kvm/booke.c
>> @@ -20,6 +20,7 @@
>>
>> #include <asm/cputable.h>
>> #include <linux/uaccess.h>
>> +#include <asm/interrupt.h>
>> #include <asm/kvm_ppc.h>
>> #include <asm/cacheflush.h>
>> #include <asm/dbell.h>
>> diff --git a/arch/powerpc/mm/book3s64/hash_utils.c
>> b/arch/powerpc/mm/book3s64/hash_utils.c
>> index 77073a256cff..453afb9ae9b4 100644
>> --- a/arch/powerpc/mm/book3s64/hash_utils.c
>> +++ b/arch/powerpc/mm/book3s64/hash_utils.c
>> @@ -38,6 +38,7 @@
>> #include <linux/pgtable.h>
>>
>> #include <asm/debugfs.h>
>> +#include <asm/interrupt.h>
>> #include <asm/processor.h>
>> #include <asm/mmu.h>
>> #include <asm/mmu_context.h>
>> @@ -1512,7 +1513,7 @@ int hash_page(unsigned long ea, unsigned long access,
>> unsigned long trap,
>> }
>> EXPORT_SYMBOL_GPL(hash_page);
>>
>> -long do_hash_fault(struct pt_regs *regs)
>> +DEFINE_INTERRUPT_HANDLER_RET(__do_hash_fault)
>> {
>> unsigned long ea = regs->dar;
>> unsigned long dsisr = regs->dsisr;
>> @@ -1522,27 +1523,6 @@ long do_hash_fault(struct pt_regs *regs)
>> unsigned int region_id;
>> long err;
>>
>> - if (unlikely(dsisr & (DSISR_BAD_FAULT_64S | DSISR_DABRMATCH |
>> DSISR_KEYFAULT)))
>> - goto page_fault;
>> -
>> - /*
>> - * If we are in an "NMI" (e.g., an interrupt when soft-disabled), then
>> - * don't call hash_page, just fail the fault. This is required to
>> - * prevent re-entrancy problems in the hash code, namely perf
>> - * interrupts hitting while something holds H_PAGE_BUSY, and taking a
>> - * hash fault. See the comment in hash_preload().
>> - *
>> - * We come here as a result of a DSI at a point where we don't want
>> - * to call hash_page, such as when we are accessing memory (possibly
>> - * user memory) inside a PMU interrupt that occurred while interrupts
>> - * were soft-disabled. We want to invoke the exception handler for
>> - * the access, or panic if there isn't a handler.
>> - */
>> - if (unlikely(in_nmi())) {
>> - bad_page_fault(regs, SIGSEGV);
>> - return 0;
>> - }
>> -
>> region_id = get_region_id(ea);
>> if ((region_id == VMALLOC_REGION_ID) || (region_id == IO_REGION_ID))
>> mm = &init_mm;
>> @@ -1583,13 +1563,44 @@ long do_hash_fault(struct pt_regs *regs)
>> err = 0;
>>
>> } else if (err) {
>> -page_fault:
>> err = do_page_fault(regs);
>> }
>>
>> return err;
>> }
>>
>> +/*
>> + * The _RAW interrupt entry checks for the in_nmi() case before
>> + * running the full handler.
>> + */
>> +DEFINE_INTERRUPT_HANDLER_RAW(do_hash_fault)
>
> Could we do that split into __do_hash_fault() / do_hash_fault() in a
> preceeding patch ?
Yeah sure.
>> +{
>> + unsigned long dsisr = regs->dsisr;
>> +
>> + if (unlikely(dsisr & (DSISR_BAD_FAULT_64S | DSISR_DABRMATCH |
>> DSISR_KEYFAULT)))
>> + return do_page_fault(regs);
>> +
>> + /*
>> + * If we are in an "NMI" (e.g., an interrupt when soft-disabled), then
>> + * don't call hash_page, just fail the fault. This is required to
>> + * prevent re-entrancy problems in the hash code, namely perf
>> + * interrupts hitting while something holds H_PAGE_BUSY, and taking a
>> + * hash fault. See the comment in hash_preload().
>> + *
>> + * We come here as a result of a DSI at a point where we don't want
>> + * to call hash_page, such as when we are accessing memory (possibly
>> + * user memory) inside a PMU interrupt that occurred while interrupts
>> + * were soft-disabled. We want to invoke the exception handler for
>> + * the access, or panic if there isn't a handler.
>> + */
>> + if (unlikely(in_nmi())) {
>> + do_bad_page_fault(regs);
>> + return 0;
>> + }
>> +
>> + return __do_hash_fault(regs);
>> +}
>> +
>> #ifdef CONFIG_PPC_MM_SLICES
>> static bool should_hash_preload(struct mm_struct *mm, unsigned long ea)
>> {
>> diff --git a/arch/powerpc/mm/book3s64/slb.c b/arch/powerpc/mm/book3s64/slb.c
>> index c581548b533f..0ae10adae203 100644
>> --- a/arch/powerpc/mm/book3s64/slb.c
>> +++ b/arch/powerpc/mm/book3s64/slb.c
>> @@ -10,6 +10,7 @@
>> */
>>
>> #include <asm/asm-prototypes.h>
>> +#include <asm/interrupt.h>
>> #include <asm/mmu.h>
>> #include <asm/mmu_context.h>
>> #include <asm/paca.h>
>> @@ -813,7 +814,7 @@ static long slb_allocate_user(struct mm_struct *mm,
>> unsigned long ea)
>> return slb_insert_entry(ea, context, flags, ssize, false);
>> }
>>
>> -long do_slb_fault(struct pt_regs *regs)
>> +DEFINE_INTERRUPT_HANDLER_RAW(do_slb_fault)
>> {
>> unsigned long ea = regs->dar;
>> unsigned long id = get_region_id(ea);
>> @@ -827,17 +828,19 @@ long do_slb_fault(struct pt_regs *regs)
>> /*
>> * SLB kernel faults must be very careful not to touch anything
>> * that is not bolted. E.g., PACA and global variables are okay,
>> - * mm->context stuff is not.
>> - *
>> - * SLB user faults can access all of kernel memory, but must be
>> - * careful not to touch things like IRQ state because it is not
>> - * "reconciled" here. The difficulty is that we must use
>> - * fast_exception_return to return from kernel SLB faults without
>> - * looking at possible non-bolted memory. We could test user vs
>> - * kernel faults in the interrupt handler asm and do a full fault,
>> - * reconcile, ret_from_except for user faults which would make them
>> - * first class kernel code. But for performance it's probably nicer
>> - * if they go via fast_exception_return too.
>> + * mm->context stuff is not. SLB user faults may access all of
>> + * memory (and induce one recursive SLB kernel fault), so the
>> + * kernel fault must not trample on the user fault state at those
>> + * points.
>> + */
>> +
>> + /*
>> + * This is a _RAW interrupt handler, so it must not touch local
>> + * irq state, or schedule. We could test for usermode and upgrade
>> + * to a normal process context (synchronous) interrupt for those,
>> + * which would make them first-class kernel code and able to be
>> + * traced and instrumented, although performance would suffer a
>> + * bit, it would probably be a good tradeoff.
>
> Is the comment change really related to the wrapper macros ?
You're right. Aneesh wanted comments for _RAW so I added them but
pointed out that the restriction already exists, it's just that it
may not have been obvious before.
Thanks for the good review.
Thanks,
Nick
