/* * 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> #ifndef CONFIG_64BIT#define LONG "%08lx "#define FOURLONG "%08lx %08lx %08lx %08lx\n"static int kstack_depth_to_print = 12;#else /* CONFIG_64BIT */#define LONG "%016lx "#define FOURLONG "%016lx %016lx %016lx %016lx\n"static int kstack_depth_to_print = 20;#endif /* CONFIG_64BIT */ /* * 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 < kstack_depth_to_print; i++) {		if (((addr_t) stack & (THREAD_SIZE-1)) == 0)			break;		if ((i * sizeof(long) % 32) == 0)			printk("%s       ", i == 0 ? "" : "\n");		printk(LONG, *stack++);	}	printk("\n");	show_trace(task, sp);} static void show_last_breaking_event(struct pt_regs *regs){#ifdef CONFIG_64BIT	printk("Last Breaking-Event-Address:\n");	printk(" [<%016lx>] %pSR\n", regs->args[0], (void *)regs->args[0]);#endif} 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 (%pSR)\n",	       mode, (void *) regs->psw.mask,	       (void *) regs->psw.addr,	       (void *) regs->psw.addr);	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));#ifdef CONFIG_64BIT	printk(" EA:%x", mask_bits(regs, PSW_MASK_EA | PSW_MASK_BA));#endif	printk("\n%s GPRS: " FOURLONG, mode,	       regs->gprs[0], regs->gprs[1], regs->gprs[2], regs->gprs[3]);	printk("           " FOURLONG,	       regs->gprs[4], regs->gprs[5], regs->gprs[6], regs->gprs[7]);	printk("           " FOURLONG,	       regs->gprs[8], regs->gprs[9], regs->gprs[10], regs->gprs[11]);	printk("           " FOURLONG,	       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 [#%d] ", str, regs->int_code & 0xffff, ++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);}