[linux-2.6-block.git] / arch / s390 / kernel / dumpstack.c

/*
 * Stack dumping functions
 *
 *  Copyright IBM Corp. 1999, 2013
 */

#include <linux/kallsyms.h>
#include <linux/hardirq.h>
#include <linux/kprobes.h>
#include <linux/utsname.h>
#include <linux/export.h>
#include <linux/kdebug.h>
#include <linux/ptrace.h>
#include <linux/module.h>
#include <linux/sched.h>
#include <asm/processor.h>
#include <asm/debug.h>
#include <asm/dis.h>
#include <asm/ipl.h>

/*
 * For show_trace we have tree different stack to consider:
 *   - the panic stack which is used if the kernel stack has overflown
 *   - the asynchronous interrupt stack (cpu related)
 *   - the synchronous kernel stack (process related)
 * The stack trace can start at any of the three stack and can potentially
 * touch all of them. The order is: panic stack, async stack, sync stack.
 */
static unsigned long
__show_trace(unsigned long sp, unsigned long low, unsigned long high)
{
	struct stack_frame *sf;
	struct pt_regs *regs;
	unsigned long addr;

	while (1) {
		sp = sp & PSW_ADDR_INSN;
		if (sp < low || sp > high - sizeof(*sf))
			return sp;
		sf = (struct stack_frame *) sp;
		addr = sf->gprs[8] & PSW_ADDR_INSN;
		printk("([<%016lx>] %pSR)\n", addr, (void *)addr);
		/* Follow the backchain. */
		while (1) {
			low = sp;
			sp = sf->back_chain & PSW_ADDR_INSN;
			if (!sp)
				break;
			if (sp <= low || sp > high - sizeof(*sf))
				return sp;
			sf = (struct stack_frame *) sp;
			addr = sf->gprs[8] & PSW_ADDR_INSN;
			printk(" [<%016lx>] %pSR\n", addr, (void *)addr);
		}
		/* Zero backchain detected, check for interrupt frame. */
		sp = (unsigned long) (sf + 1);
		if (sp <= low || sp > high - sizeof(*regs))
			return sp;
		regs = (struct pt_regs *) sp;
		addr = regs->psw.addr & PSW_ADDR_INSN;
		printk(" [<%016lx>] %pSR\n", addr, (void *)addr);
		low = sp;
		sp = regs->gprs[15];
	}
}

static void show_trace(struct task_struct *task, unsigned long *stack)
{
	const unsigned long frame_size =
		STACK_FRAME_OVERHEAD + sizeof(struct pt_regs);
	register unsigned long __r15 asm ("15");
	unsigned long sp;

	sp = (unsigned long) stack;
	if (!sp)
		sp = task ? task->thread.ksp : __r15;
	printk("Call Trace:\n");
#ifdef CONFIG_CHECK_STACK
	sp = __show_trace(sp,
			  S390_lowcore.panic_stack + frame_size - 4096,
			  S390_lowcore.panic_stack + frame_size);
#endif
	sp = __show_trace(sp,
			  S390_lowcore.async_stack + frame_size - ASYNC_SIZE,
			  S390_lowcore.async_stack + frame_size);
	if (task)
		__show_trace(sp, (unsigned long) task_stack_page(task),
			     (unsigned long) task_stack_page(task) + THREAD_SIZE);
	else
		__show_trace(sp, S390_lowcore.thread_info,
			     S390_lowcore.thread_info + THREAD_SIZE);
	if (!task)
		task = current;
	debug_show_held_locks(task);
}

void show_stack(struct task_struct *task, unsigned long *sp)
{
	register unsigned long *__r15 asm ("15");
	unsigned long *stack;
	int i;

	if (!sp)
		stack = task ? (unsigned long *) task->thread.ksp : __r15;
	else
		stack = sp;

	for (i = 0; i < 20; i++) {
		if (((addr_t) stack & (THREAD_SIZE-1)) == 0)
			break;
		if ((i * sizeof(long) % 32) == 0)
			printk("%s       ", i == 0 ? "" : "\n");
		printk("%016lx ", *stack++);
	}
	printk("\n");
	show_trace(task, sp);
}

static void show_last_breaking_event(struct pt_regs *regs)
{
	printk("Last Breaking-Event-Address:\n");
	printk(" [<%016lx>] %pSR\n", regs->args[0], (void *)regs->args[0]);
}

static inline int mask_bits(struct pt_regs *regs, unsigned long bits)
{
	return (regs->psw.mask & bits) / ((~bits + 1) & bits);
}

void show_registers(struct pt_regs *regs)
{
	char *mode;

	mode = user_mode(regs) ? "User" : "Krnl";
	printk("%s PSW : %p %p", mode, (void *)regs->psw.mask, (void *)regs->psw.addr);
	if (!user_mode(regs))
		printk(" (%pSR)", (void *)regs->psw.addr);
	printk("\n");
	printk("           R:%x T:%x IO:%x EX:%x Key:%x M:%x W:%x "
	       "P:%x AS:%x CC:%x PM:%x", mask_bits(regs, PSW_MASK_PER),
	       mask_bits(regs, PSW_MASK_DAT), mask_bits(regs, PSW_MASK_IO),
	       mask_bits(regs, PSW_MASK_EXT), mask_bits(regs, PSW_MASK_KEY),
	       mask_bits(regs, PSW_MASK_MCHECK), mask_bits(regs, PSW_MASK_WAIT),
	       mask_bits(regs, PSW_MASK_PSTATE), mask_bits(regs, PSW_MASK_ASC),
	       mask_bits(regs, PSW_MASK_CC), mask_bits(regs, PSW_MASK_PM));
	printk(" EA:%x", mask_bits(regs, PSW_MASK_EA | PSW_MASK_BA));
	printk("\n%s GPRS: %016lx %016lx %016lx %016lx\n", mode,
	       regs->gprs[0], regs->gprs[1], regs->gprs[2], regs->gprs[3]);
	printk("           %016lx %016lx %016lx %016lx\n",
	       regs->gprs[4], regs->gprs[5], regs->gprs[6], regs->gprs[7]);
	printk("           %016lx %016lx %016lx %016lx\n",
	       regs->gprs[8], regs->gprs[9], regs->gprs[10], regs->gprs[11]);
	printk("           %016lx %016lx %016lx %016lx\n",
	       regs->gprs[12], regs->gprs[13], regs->gprs[14], regs->gprs[15]);
	show_code(regs);
}

void show_regs(struct pt_regs *regs)
{
	show_regs_print_info(KERN_DEFAULT);
	show_registers(regs);
	/* Show stack backtrace if pt_regs is from kernel mode */
	if (!user_mode(regs))
		show_trace(NULL, (unsigned long *) regs->gprs[15]);
	show_last_breaking_event(regs);
}

static DEFINE_SPINLOCK(die_lock);

void die(struct pt_regs *regs, const char *str)
{
	static int die_counter;

	oops_enter();
	lgr_info_log();
	debug_stop_all();
	console_verbose();
	spin_lock_irq(&die_lock);
	bust_spinlocks(1);
	printk("%s: %04x ilc:%d [#%d] ", str, regs->int_code & 0xffff,
	       regs->int_code >> 17, ++die_counter);
#ifdef CONFIG_PREEMPT
	printk("PREEMPT ");
#endif
#ifdef CONFIG_SMP
	printk("SMP ");
#endif
#ifdef CONFIG_DEBUG_PAGEALLOC
	printk("DEBUG_PAGEALLOC");
#endif
	printk("\n");
	notify_die(DIE_OOPS, str, regs, 0, regs->int_code & 0xffff, SIGSEGV);
	print_modules();
	show_regs(regs);
	bust_spinlocks(0);
	add_taint(TAINT_DIE, LOCKDEP_NOW_UNRELIABLE);
	spin_unlock_irq(&die_lock);
	if (in_interrupt())
		panic("Fatal exception in interrupt");
	if (panic_on_oops)
		panic("Fatal exception: panic_on_oops");
	oops_exit();
	do_exit(SIGSEGV);
}
Commit	Line	Data
1bca09f7 HC	1	/*
	2	* Stack dumping functions
	3	*
	4	* Copyright IBM Corp. 1999, 2013
	5	*/
	6
	7	#include <linux/kallsyms.h>
	8	#include <linux/hardirq.h>
	9	#include <linux/kprobes.h>
	10	#include <linux/utsname.h>
	11	#include <linux/export.h>
	12	#include <linux/kdebug.h>
	13	#include <linux/ptrace.h>
	14	#include <linux/module.h>
	15	#include <linux/sched.h>
	16	#include <asm/processor.h>
	17	#include <asm/debug.h>
0f20822a	18	#include <asm/dis.h>
1bca09f7 HC	19	#include <asm/ipl.h>
1bca09f7 HC	20
1bca09f7 HC	21	/*
	22	* For show_trace we have tree different stack to consider:
	23	* - the panic stack which is used if the kernel stack has overflown
	24	* - the asynchronous interrupt stack (cpu related)
	25	* - the synchronous kernel stack (process related)
	26	* The stack trace can start at any of the three stack and can potentially
	27	* touch all of them. The order is: panic stack, async stack, sync stack.
	28	*/
	29	static unsigned long
	30	__show_trace(unsigned long sp, unsigned long low, unsigned long high)
	31	{
	32	struct stack_frame *sf;
	33	struct pt_regs *regs;
8237ac3c	34	unsigned long addr;
1bca09f7 HC	35
	36	while (1) {
	37	sp = sp & PSW_ADDR_INSN;
	38	if (sp < low \|\| sp > high - sizeof(*sf))
	39	return sp;
	40	sf = (struct stack_frame *) sp;
8237ac3c HC	41	addr = sf->gprs[8] & PSW_ADDR_INSN;
8237ac3c HC	42	printk("([<%016lx>] %pSR)\n", addr, (void *)addr);
1bca09f7 HC	43	/* Follow the backchain. */
	44	while (1) {
	45	low = sp;
	46	sp = sf->back_chain & PSW_ADDR_INSN;
	47	if (!sp)
	48	break;
	49	if (sp <= low \|\| sp > high - sizeof(*sf))
	50	return sp;
	51	sf = (struct stack_frame *) sp;
8237ac3c HC	52	addr = sf->gprs[8] & PSW_ADDR_INSN;
8237ac3c HC	53	printk(" [<%016lx>] %pSR\n", addr, (void *)addr);
1bca09f7 HC	54	}
	55	/* Zero backchain detected, check for interrupt frame. */
	56	sp = (unsigned long) (sf + 1);
	57	if (sp <= low \|\| sp > high - sizeof(*regs))
	58	return sp;
	59	regs = (struct pt_regs *) sp;
8237ac3c HC	60	addr = regs->psw.addr & PSW_ADDR_INSN;
8237ac3c HC	61	printk(" [<%016lx>] %pSR\n", addr, (void *)addr);
1bca09f7 HC	62	low = sp;
	63	sp = regs->gprs[15];
	64	}
	65	}
	66
	67	static void show_trace(struct task_struct task, unsigned long stack)
	68	{
9cc5c206 MS	69	const unsigned long frame_size =
9cc5c206 MS	70	STACK_FRAME_OVERHEAD + sizeof(struct pt_regs);
1bca09f7 HC	71	register unsigned long __r15 asm ("15");
	72	unsigned long sp;
	73
	74	sp = (unsigned long) stack;
	75	if (!sp)
	76	sp = task ? task->thread.ksp : __r15;
	77	printk("Call Trace:\n");
	78	#ifdef CONFIG_CHECK_STACK
9cc5c206 MS	79	sp = __show_trace(sp,
	80	S390_lowcore.panic_stack + frame_size - 4096,
	81	S390_lowcore.panic_stack + frame_size);
1bca09f7	82	#endif
9cc5c206 MS	83	sp = __show_trace(sp,
	84	S390_lowcore.async_stack + frame_size - ASYNC_SIZE,
	85	S390_lowcore.async_stack + frame_size);
1bca09f7 HC	86	if (task)
	87	__show_trace(sp, (unsigned long) task_stack_page(task),
	88	(unsigned long) task_stack_page(task) + THREAD_SIZE);
	89	else
	90	__show_trace(sp, S390_lowcore.thread_info,
	91	S390_lowcore.thread_info + THREAD_SIZE);
	92	if (!task)
	93	task = current;
	94	debug_show_held_locks(task);
	95	}
	96
	97	void show_stack(struct task_struct task, unsigned long sp)
	98	{
	99	register unsigned long *__r15 asm ("15");
	100	unsigned long *stack;
	101	int i;
	102
	103	if (!sp)
	104	stack = task ? (unsigned long *) task->thread.ksp : __r15;
	105	else
	106	stack = sp;
	107
5a79859a	108	for (i = 0; i < 20; i++) {
1bca09f7 HC	109	if (((addr_t) stack & (THREAD_SIZE-1)) == 0)
	110	break;
	111	if ((i * sizeof(long) % 32) == 0)
	112	printk("%s ", i == 0 ? "" : "\n");
5a79859a	113	printk("%016lx ", *stack++);
1bca09f7 HC	114	}
	115	printk("\n");
	116	show_trace(task, sp);
	117	}
	118
	119	static void show_last_breaking_event(struct pt_regs *regs)
	120	{
1bca09f7	121	printk("Last Breaking-Event-Address:\n");
8237ac3c	122	printk(" [<%016lx>] %pSR\n", regs->args[0], (void *)regs->args[0]);
1bca09f7 HC	123	}
1bca09f7 HC	124
1bca09f7 HC	125	static inline int mask_bits(struct pt_regs *regs, unsigned long bits)
	126	{
	127	return (regs->psw.mask & bits) / ((~bits + 1) & bits);
	128	}
	129
	130	void show_registers(struct pt_regs *regs)
	131	{
	132	char *mode;
	133
	134	mode = user_mode(regs) ? "User" : "Krnl";
9ea80662 HC	135	printk("%s PSW : %p %p", mode, (void )regs->psw.mask, (void )regs->psw.addr);
	136	if (!user_mode(regs))
	137	printk(" (%pSR)", (void *)regs->psw.addr);
	138	printk("\n");
1bca09f7 HC	139	printk(" R:%x T:%x IO:%x EX:%x Key:%x M:%x W:%x "
	140	"P:%x AS:%x CC:%x PM:%x", mask_bits(regs, PSW_MASK_PER),
	141	mask_bits(regs, PSW_MASK_DAT), mask_bits(regs, PSW_MASK_IO),
	142	mask_bits(regs, PSW_MASK_EXT), mask_bits(regs, PSW_MASK_KEY),
	143	mask_bits(regs, PSW_MASK_MCHECK), mask_bits(regs, PSW_MASK_WAIT),
	144	mask_bits(regs, PSW_MASK_PSTATE), mask_bits(regs, PSW_MASK_ASC),
	145	mask_bits(regs, PSW_MASK_CC), mask_bits(regs, PSW_MASK_PM));
1bca09f7	146	printk(" EA:%x", mask_bits(regs, PSW_MASK_EA \| PSW_MASK_BA));
5a79859a	147	printk("\n%s GPRS: %016lx %016lx %016lx %016lx\n", mode,
1bca09f7	148	regs->gprs[0], regs->gprs[1], regs->gprs[2], regs->gprs[3]);
5a79859a	149	printk(" %016lx %016lx %016lx %016lx\n",
1bca09f7	150	regs->gprs[4], regs->gprs[5], regs->gprs[6], regs->gprs[7]);
5a79859a	151	printk(" %016lx %016lx %016lx %016lx\n",
1bca09f7	152	regs->gprs[8], regs->gprs[9], regs->gprs[10], regs->gprs[11]);
5a79859a	153	printk(" %016lx %016lx %016lx %016lx\n",
1bca09f7 HC	154	regs->gprs[12], regs->gprs[13], regs->gprs[14], regs->gprs[15]);
	155	show_code(regs);
	156	}
	157
	158	void show_regs(struct pt_regs *regs)
	159	{
a43cb95d	160	show_regs_print_info(KERN_DEFAULT);
1bca09f7 HC	161	show_registers(regs);
	162	/* Show stack backtrace if pt_regs is from kernel mode */
	163	if (!user_mode(regs))
	164	show_trace(NULL, (unsigned long *) regs->gprs[15]);
	165	show_last_breaking_event(regs);
	166	}
	167
	168	static DEFINE_SPINLOCK(die_lock);
	169
	170	void die(struct pt_regs regs, const char str)
	171	{
	172	static int die_counter;
	173
	174	oops_enter();
	175	lgr_info_log();
	176	debug_stop_all();
	177	console_verbose();
	178	spin_lock_irq(&die_lock);
	179	bust_spinlocks(1);
413d4047 HC	180	printk("%s: %04x ilc:%d [#%d] ", str, regs->int_code & 0xffff,
413d4047 HC	181	regs->int_code >> 17, ++die_counter);
1bca09f7 HC	182	#ifdef CONFIG_PREEMPT
	183	printk("PREEMPT ");
	184	#endif
	185	#ifdef CONFIG_SMP
	186	printk("SMP ");
	187	#endif
	188	#ifdef CONFIG_DEBUG_PAGEALLOC
	189	printk("DEBUG_PAGEALLOC");
	190	#endif
	191	printk("\n");
	192	notify_die(DIE_OOPS, str, regs, 0, regs->int_code & 0xffff, SIGSEGV);
	193	print_modules();
	194	show_regs(regs);
	195	bust_spinlocks(0);
	196	add_taint(TAINT_DIE, LOCKDEP_NOW_UNRELIABLE);
	197	spin_unlock_irq(&die_lock);
	198	if (in_interrupt())
	199	panic("Fatal exception in interrupt");
	200	if (panic_on_oops)
	201	panic("Fatal exception: panic_on_oops");
	202	oops_exit();
	203	do_exit(SIGSEGV);
	204	}