Commit 760ca4dc authored by Anton Blanchard's avatar Anton Blanchard Committed by Benjamin Herrenschmidt
Browse files

powerpc: Rework die() 



Our die() code was based off a very old x86 version. Update it to
mirror the current x86 code.

Signed-off-by: default avatarAnton Blanchard <anton@samba.org>
Signed-off-by: default avatarBenjamin Herrenschmidt <benh@kernel.crashing.org>
parent 8c27474a

arch/powerpc/include/asm/system.h

+1 −1
Original line number Diff line number Diff line
@@ -193,8 +193,8 @@ extern void cacheable_memzero(void *p, unsigned int nb); 
extern void *cacheable_memcpy(void *, const void *, unsigned int);

extern int do_page_fault(struct pt_regs *, unsigned long, unsigned long);

extern void bad_page_fault(struct pt_regs *, unsigned long, int);

extern int die(const char *, struct pt_regs *, long);

extern void _exception(int, struct pt_regs *, int, unsigned long);

extern void die(const char *, struct pt_regs *, long);

extern void _nmask_and_or_msr(unsigned long nmask, unsigned long or_val);



#ifdef CONFIG_BOOKE_WDT

arch/powerpc/kernel/traps.c

+73 −55
Original line number Diff line number Diff line
@@ -98,18 +98,14 @@ static void pmac_backlight_unblank(void) 
static inline void pmac_backlight_unblank(void) { }

#endif



int die(const char *str, struct pt_regs *regs, long err)

{

	static struct {

		raw_spinlock_t lock;

		u32 lock_owner;

		int lock_owner_depth;

	} die = {

		.lock =			__RAW_SPIN_LOCK_UNLOCKED(die.lock),

		.lock_owner =		-1,

		.lock_owner_depth =	0

	};

static arch_spinlock_t die_lock = __ARCH_SPIN_LOCK_UNLOCKED;

static int die_owner = -1;

static unsigned int die_nest_count;

static int die_counter;



static unsigned __kprobes long oops_begin(struct pt_regs *regs)

{

	int cpu;

	unsigned long flags;



	if (debugger(regs))
@@ -117,50 +113,37 @@ int die(const char *str, struct pt_regs *regs, long err) 


	oops_enter();



	if (die.lock_owner != raw_smp_processor_id()) {

	/* racy, but better than risking deadlock. */

	raw_local_irq_save(flags);

	cpu = smp_processor_id();

	if (!arch_spin_trylock(&die_lock)) {

		if (cpu == die_owner)

			/* nested oops. should stop eventually */;

		else

			arch_spin_lock(&die_lock);

	}

	die_nest_count++;

	die_owner = cpu;

	console_verbose();

		raw_spin_lock_irqsave(&die.lock, flags);

		die.lock_owner = smp_processor_id();

		die.lock_owner_depth = 0;

	bust_spinlocks(1);

	if (machine_is(powermac))

		pmac_backlight_unblank();

	} else {

		local_save_flags(flags);

	}



	if (++die.lock_owner_depth < 3) {

		printk("Oops: %s, sig: %ld [#%d]\n", str, err, ++die_counter);

#ifdef CONFIG_PREEMPT

		printk("PREEMPT ");

#endif

#ifdef CONFIG_SMP

		printk("SMP NR_CPUS=%d ", NR_CPUS);

#endif

#ifdef CONFIG_DEBUG_PAGEALLOC

		printk("DEBUG_PAGEALLOC ");

#endif

#ifdef CONFIG_NUMA

		printk("NUMA ");

#endif

		printk("%s\n", ppc_md.name ? ppc_md.name : "");



		if (notify_die(DIE_OOPS, str, regs, err, 255,

			       SIGSEGV) == NOTIFY_STOP)

			return 1;



		print_modules();

		show_regs(regs);

	} else {

		printk("Recursive die() failure, output suppressed\n");

	return flags;

}



static void __kprobes oops_end(unsigned long flags, struct pt_regs *regs,

			       int signr)

{

	bust_spinlocks(0);

	die.lock_owner = -1;

	die_owner = -1;

	add_taint(TAINT_DIE);

	die_nest_count--;

	oops_exit();

	printk("\n");

	raw_spin_unlock_irqrestore(&die.lock, flags);

	if (!die_nest_count)

		/* Nest count reaches zero, release the lock. */

		arch_spin_unlock(&die_lock);

	raw_local_irq_restore(flags);



	/*

	 * A system reset (0x100) is a request to dump, so we always send
@@ -177,6 +160,9 @@ int die(const char *str, struct pt_regs *regs, long err) 
		crash_kexec_secondary(regs);

	}



	if (!signr)

		return;



	/*

	 * While our oops output is serialised by a spinlock, output

	 * from panic() called below can race and corrupt it. If we
@@ -190,15 +176,46 @@ int die(const char *str, struct pt_regs *regs, long err) 


	if (in_interrupt())

		panic("Fatal exception in interrupt");



	if (panic_on_oops)

		panic("Fatal exception");

	do_exit(signr);

}



static int __kprobes __die(const char *str, struct pt_regs *regs, long err)

{

	printk("Oops: %s, sig: %ld [#%d]\n", str, err, ++die_counter);

#ifdef CONFIG_PREEMPT

	printk("PREEMPT ");

#endif

#ifdef CONFIG_SMP

	printk("SMP NR_CPUS=%d ", NR_CPUS);

#endif

#ifdef CONFIG_DEBUG_PAGEALLOC

	printk("DEBUG_PAGEALLOC ");

#endif

#ifdef CONFIG_NUMA

	printk("NUMA ");

#endif

	printk("%s\n", ppc_md.name ? ppc_md.name : "");



	do_exit(err);

	if (notify_die(DIE_OOPS, str, regs, err, 255, SIGSEGV) == NOTIFY_STOP)

		return 1;



	print_modules();

	show_regs(regs);



	return 0;

}



void die(const char *str, struct pt_regs *regs, long err)

{

	unsigned long flags = oops_begin(regs);



	if (__die(str, regs, err))

		err = 0;

	oops_end(flags, regs, err);

}



void user_single_step_siginfo(struct task_struct *tsk,

				struct pt_regs *regs, siginfo_t *info)

{
@@ -217,10 +234,11 @@ void _exception(int signr, struct pt_regs *regs, int code, unsigned long addr) 
			"at %016lx nip %016lx lr %016lx code %x\n";



	if (!user_mode(regs)) {

		if (die("Exception in kernel mode", regs, signr))

		die("Exception in kernel mode", regs, signr);

		return;

	} else if (show_unhandled_signals &&

		   unhandled_signal(current, signr)) {

	}



	if (show_unhandled_signals && unhandled_signal(current, signr)) {

		printk_ratelimited(regs->msr & MSR_64BIT ? fmt64 : fmt32,

				   current->comm, current->pid, signr,

				   addr, regs->nip, regs->link, code);