This moves the common NMI entry and exit code into the interrupt handler wrappers.
This changes the behaviour of soft-NMI (watchdog) and HMI interrupts, and also MCE interrupts on 64e, by adding missing parts of the NMI entry to them. Signed-off-by: Nicholas Piggin <npig...@gmail.com> --- arch/powerpc/include/asm/interrupt.h | 26 +++++++++++++++++++ arch/powerpc/kernel/mce.c | 12 --------- arch/powerpc/kernel/traps.c | 38 +++++----------------------- arch/powerpc/kernel/watchdog.c | 10 +++----- 4 files changed, 37 insertions(+), 49 deletions(-) diff --git a/arch/powerpc/include/asm/interrupt.h b/arch/powerpc/include/asm/interrupt.h index 83fe1d64cf23..69eb8a432984 100644 --- a/arch/powerpc/include/asm/interrupt.h +++ b/arch/powerpc/include/asm/interrupt.h @@ -31,6 +31,27 @@ static inline void interrupt_enter_prepare(struct pt_regs *regs) } #endif /* CONFIG_PPC_BOOK3S_64 */ +struct interrupt_nmi_state { +#ifdef CONFIG_PPC64 + u8 ftrace_enabled; +#endif +}; + +static inline void interrupt_nmi_enter_prepare(struct pt_regs *regs, struct interrupt_nmi_state *state) +{ + this_cpu_set_ftrace_enabled(0); + + nmi_enter(); +} + +static inline void interrupt_nmi_exit_prepare(struct pt_regs *regs, struct interrupt_nmi_state *state) +{ + nmi_exit(); + + this_cpu_set_ftrace_enabled(state->ftrace_enabled); +} + + /** * DECLARE_INTERRUPT_HANDLER_RAW - Declare raw interrupt handler function * @func: Function name of the entry point @@ -177,10 +198,15 @@ static __always_inline long ___##func(struct pt_regs *regs); \ \ __visible noinstr long func(struct pt_regs *regs) \ { \ + struct interrupt_nmi_state state; \ long ret; \ \ + interrupt_nmi_enter_prepare(regs, &state); \ + \ ret = ___##func (regs); \ \ + interrupt_nmi_exit_prepare(regs, &state); \ + \ return ret; \ } \ \ diff --git a/arch/powerpc/kernel/mce.c b/arch/powerpc/kernel/mce.c index d0bbcc4fe13c..9f39deed4fca 100644 --- a/arch/powerpc/kernel/mce.c +++ b/arch/powerpc/kernel/mce.c @@ -592,13 +592,6 @@ EXPORT_SYMBOL_GPL(machine_check_print_event_info); DEFINE_INTERRUPT_HANDLER_NMI(machine_check_early) { long handled = 0; - bool nested = in_nmi(); - u8 ftrace_enabled = this_cpu_get_ftrace_enabled(); - - this_cpu_set_ftrace_enabled(0); - - if (!nested) - nmi_enter(); hv_nmi_check_nonrecoverable(regs); @@ -608,11 +601,6 @@ DEFINE_INTERRUPT_HANDLER_NMI(machine_check_early) if (ppc_md.machine_check_early) handled = ppc_md.machine_check_early(regs); - if (!nested) - nmi_exit(); - - this_cpu_set_ftrace_enabled(ftrace_enabled); - return handled; } diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c index 3784578db630..01ddbe5ed5a4 100644 --- a/arch/powerpc/kernel/traps.c +++ b/arch/powerpc/kernel/traps.c @@ -443,11 +443,6 @@ DEFINE_INTERRUPT_HANDLER_NMI(system_reset_exception) { unsigned long hsrr0, hsrr1; bool saved_hsrrs = false; - u8 ftrace_enabled = this_cpu_get_ftrace_enabled(); - - this_cpu_set_ftrace_enabled(0); - - nmi_enter(); /* * System reset can interrupt code where HSRRs are live and MSR[RI]=1. @@ -519,10 +514,6 @@ DEFINE_INTERRUPT_HANDLER_NMI(system_reset_exception) mtspr(SPRN_HSRR1, hsrr1); } - nmi_exit(); - - this_cpu_set_ftrace_enabled(ftrace_enabled); - /* What should we do here? We could issue a shutdown or hard reset. */ return 0; @@ -828,6 +819,12 @@ int machine_check_generic(struct pt_regs *regs) #endif /* everything else */ +/* + * BOOK3S_64 does not call this handler as a non-maskable interrupt + * (it uses its own early real-mode handler to handle the MCE proper + * and then raises irq_work to call this handler when interrupts are + * enabled). + */ #ifdef CONFIG_PPC_BOOK3S_64 DEFINE_INTERRUPT_HANDLER_ASYNC(machine_check_exception) #else @@ -836,20 +833,6 @@ DEFINE_INTERRUPT_HANDLER_NMI(machine_check_exception) { int recover = 0; - /* - * BOOK3S_64 does not call this handler as a non-maskable interrupt - * (it uses its own early real-mode handler to handle the MCE proper - * and then raises irq_work to call this handler when interrupts are - * enabled). - * - * This is silly. The BOOK3S_64 should just call a different function - * rather than expecting semantics to magically change. Something - * like 'non_nmi_machine_check_exception()', perhaps? - */ - const bool nmi = !IS_ENABLED(CONFIG_PPC_BOOK3S_64); - - if (nmi) nmi_enter(); - __this_cpu_inc(irq_stat.mce_exceptions); add_taint(TAINT_MACHINE_CHECK, LOCKDEP_NOW_UNRELIABLE); @@ -874,24 +857,17 @@ DEFINE_INTERRUPT_HANDLER_NMI(machine_check_exception) if (check_io_access(regs)) goto bail; - if (nmi) nmi_exit(); - die("Machine check", regs, SIGBUS); /* Must die if the interrupt is not recoverable */ if (!(regs->msr & MSR_RI)) die("Unrecoverable Machine check", regs, SIGBUS); -#ifdef CONFIG_PPC_BOOK3S_64 bail: +#ifdef CONFIG_PPC_BOOK3S_64 return; #else return 0; - -bail: - if (nmi) nmi_exit(); - - return 0; #endif } diff --git a/arch/powerpc/kernel/watchdog.c b/arch/powerpc/kernel/watchdog.c index 824b9376ac35..dc39534836a3 100644 --- a/arch/powerpc/kernel/watchdog.c +++ b/arch/powerpc/kernel/watchdog.c @@ -254,11 +254,12 @@ DEFINE_INTERRUPT_HANDLER_NMI(soft_nmi_interrupt) int cpu = raw_smp_processor_id(); u64 tb; + /* should only arrive from kernel, with irqs disabled */ + WARN_ON_ONCE(!arch_irq_disabled_regs(regs)); + if (!cpumask_test_cpu(cpu, &wd_cpus_enabled)) return 0; - nmi_enter(); - __this_cpu_inc(irq_stat.soft_nmi_irqs); tb = get_tb(); @@ -266,7 +267,7 @@ DEFINE_INTERRUPT_HANDLER_NMI(soft_nmi_interrupt) wd_smp_lock(&flags); if (cpumask_test_cpu(cpu, &wd_smp_cpus_stuck)) { wd_smp_unlock(&flags); - goto out; + return 0; } set_cpu_stuck(cpu, tb); @@ -290,9 +291,6 @@ DEFINE_INTERRUPT_HANDLER_NMI(soft_nmi_interrupt) if (wd_panic_timeout_tb < 0x7fffffff) mtspr(SPRN_DEC, wd_panic_timeout_tb); -out: - nmi_exit(); - return 0; } -- 2.23.0