diff --git a/arch/powerpc/include/asm/rtas.h b/arch/powerpc/include/asm/rtas.h index 01c12339b304..0af42d20b692 100644 --- a/arch/powerpc/include/asm/rtas.h +++ b/arch/powerpc/include/asm/rtas.h @@ -58,7 +58,7 @@ struct rtas_t { unsigned long entry; /* physical address pointer */ unsigned long base; /* physical address pointer */ unsigned long size; - spinlock_t lock; + raw_spinlock_t lock; struct rtas_args args; struct device_node *dev; /* virtual address pointer */ }; diff --git a/arch/powerpc/kernel/rtas.c b/arch/powerpc/kernel/rtas.c index ee4c7609b649..d9a9974c6938 100644 --- a/arch/powerpc/kernel/rtas.c +++ b/arch/powerpc/kernel/rtas.c @@ -40,7 +40,7 @@ #include struct rtas_t rtas = { - .lock = SPIN_LOCK_UNLOCKED + .lock = __RAW_SPIN_LOCK_UNLOCKED }; EXPORT_SYMBOL(rtas); @@ -67,6 +67,28 @@ unsigned long rtas_rmo_buf; void (*rtas_flash_term_hook)(int); EXPORT_SYMBOL(rtas_flash_term_hook); +/* RTAS use home made raw locking instead of spin_lock_irqsave + * because those can be called from within really nasty contexts + * such as having the timebase stopped which would lockup with + * normal locks and spinlock debugging enabled + */ +static unsigned long lock_rtas(void) +{ + unsigned long flags; + + local_irq_save(flags); + preempt_disable(); + __raw_spin_lock_flags(&rtas.lock, flags); + return flags; +} + +static void unlock_rtas(unsigned long flags) +{ + __raw_spin_unlock(&rtas.lock); + local_irq_restore(flags); + preempt_enable(); +} + /* * call_rtas_display_status and call_rtas_display_status_delay * are designed only for very early low-level debugging, which @@ -79,7 +101,7 @@ static void call_rtas_display_status(char c) if (!rtas.base) return; - spin_lock_irqsave(&rtas.lock, s); + s = lock_rtas(); args->token = 10; args->nargs = 1; @@ -89,7 +111,7 @@ static void call_rtas_display_status(char c) enter_rtas(__pa(args)); - spin_unlock_irqrestore(&rtas.lock, s); + unlock_rtas(s); } static void call_rtas_display_status_delay(char c) @@ -411,8 +433,7 @@ int rtas_call(int token, int nargs, int nret, int *outputs, ...) if (!rtas.entry || token == RTAS_UNKNOWN_SERVICE) return -1; - /* Gotta do something different here, use global lock for now... */ - spin_lock_irqsave(&rtas.lock, s); + s = lock_rtas(); rtas_args = &rtas.args; rtas_args->token = token; @@ -439,8 +460,7 @@ int rtas_call(int token, int nargs, int nret, int *outputs, ...) outputs[i] = rtas_args->rets[i+1]; ret = (nret > 0)? rtas_args->rets[0]: 0; - /* Gotta do something different here, use global lock for now... */ - spin_unlock_irqrestore(&rtas.lock, s); + unlock_rtas(s); if (buff_copy) { log_error(buff_copy, ERR_TYPE_RTAS_LOG, 0); @@ -837,7 +857,7 @@ asmlinkage int ppc_rtas(struct rtas_args __user *uargs) buff_copy = get_errorlog_buffer(); - spin_lock_irqsave(&rtas.lock, flags); + flags = lock_rtas(); rtas.args = args; enter_rtas(__pa(&rtas.args)); @@ -848,7 +868,7 @@ asmlinkage int ppc_rtas(struct rtas_args __user *uargs) if (args.rets[0] == -1) errbuf = __fetch_rtas_last_error(buff_copy); - spin_unlock_irqrestore(&rtas.lock, flags); + unlock_rtas(flags); if (buff_copy) { if (errbuf)