/* *  arch/s390/kernel/traps.c * *  S390 version *    Copyright (C) 1999,2000 IBM Deutschland Entwicklung GmbH, IBM Corporation *    Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com), *               Denis Joseph Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com), * *  Derived from "arch/i386/kernel/traps.c" *    Copyright (C) 1991, 1992 Linus Torvalds *//* * 'Traps.c' handles hardware traps and faults after we have saved some * state in 'asm.s'. */#include <linux/config.h>#include <linux/sched.h>#include <linux/kernel.h>#include <linux/string.h>#include <linux/errno.h>#include <linux/ptrace.h>#include <linux/timer.h>#include <linux/mm.h>#include <linux/smp.h>#include <linux/smp_lock.h>#include <linux/init.h>#include <linux/delay.h>#include <linux/module.h>#include <asm/system.h>#include <asm/uaccess.h>#include <asm/io.h>#include <asm/atomic.h>#include <asm/mathemu.h>#include <asm/cpcmd.h>#include <asm/s390_ext.h>/* Called from entry.S only */extern void handle_per_exception(struct pt_regs *regs);typedef void pgm_check_handler_t(struct pt_regs *, long);pgm_check_handler_t *pgm_check_table[128];#ifdef CONFIG_SYSCTL#ifdef CONFIG_PROCESS_DEBUGint sysctl_userprocess_debug = 1;#elseint sysctl_userprocess_debug = 0;#endif#endifextern pgm_check_handler_t do_protection_exception;extern pgm_check_handler_t do_segment_exception;extern pgm_check_handler_t do_page_exception;extern pgm_check_handler_t do_pseudo_page_fault;#ifdef CONFIG_PFAULTextern int pfault_init(void);extern void pfault_fini(void);extern void pfault_interrupt(struct pt_regs *regs, __u16 error_code);static ext_int_info_t ext_int_pfault;#endifint kstack_depth_to_print = 12;/* * If the address is either in the .text section of the * kernel, or in the vmalloc'ed module regions, it *may*  * be the address of a calling routine */extern char _stext, _etext;#ifdef CONFIG_MODULESextern struct module *module_list;extern struct module kernel_module;static inline int kernel_text_address(unsigned long addr){	int retval = 0;	struct module *mod;	if (addr >= (unsigned long) &_stext &&	    addr <= (unsigned long) &_etext)		return 1;	for (mod = module_list; mod != &kernel_module; mod = mod->next) {		/* mod_bound tests for addr being inside the vmalloc'ed		 * module area. Of course it'd be better to test only		 * for the .text subset... */		if (mod_bound(addr, 0, mod)) {			retval = 1;			break;		}	}	return retval;}#elsestatic inline int kernel_text_address(unsigned long addr){	return (addr >= (unsigned long) &_stext &&		addr <= (unsigned long) &_etext);}#endifvoid show_trace(unsigned long * stack){	unsigned long backchain, low_addr, high_addr, ret_addr;	int i;	if (!stack)		stack = (unsigned long*)&stack;	printk("Call Trace: ");	low_addr = ((unsigned long) stack) & PSW_ADDR_MASK;	high_addr = (low_addr & (-THREAD_SIZE)) + THREAD_SIZE;	/* Skip the first frame (biased stack) */	backchain = *((unsigned long *) low_addr) & PSW_ADDR_MASK;	/* Print up to 8 lines */	for (i = 0; i < 8; i++) {		if (backchain < low_addr || backchain >= high_addr)			break;		ret_addr = *((unsigned long *) (backchain+56)) & PSW_ADDR_MASK;		if (!kernel_text_address(ret_addr))			break;		if (i && ((i % 6) == 0))			printk("\n   ");		printk("[<%08lx>] ", ret_addr);		low_addr = backchain;		backchain = *((unsigned long *) backchain) & PSW_ADDR_MASK;	}	printk("\n");}void show_trace_task(struct task_struct *tsk){	/*	 * We can't print the backtrace of a running process. It is	 * unreliable at best and can cause kernel oopses.	 */	if (task_has_cpu(tsk))		return;	show_trace((unsigned long *) tsk->thread.ksp);}void show_stack(unsigned long *sp){	unsigned long *stack;	int i;	// debugging aid: "show_stack(NULL);" prints the	// back trace for this cpu.	if(sp == NULL)		sp = (unsigned long*) &sp;	stack = sp;	for (i = 0; i < kstack_depth_to_print; i++) {		if (((addr_t) stack & (THREAD_SIZE-1)) == 0)			break;		if (i && ((i % 8) == 0))			printk("\n       ");		printk("%08lx ", *stack++);	}	printk("\n");	show_trace(sp);}void show_registers(struct pt_regs *regs){	mm_segment_t old_fs;	char *mode;	int i;	mode = (regs->psw.mask & PSW_PROBLEM_STATE) ? "User" : "Krnl";	printk("%s PSW : %08lx %08lx\n",	       mode, (unsigned long) regs->psw.mask,	       (unsigned long) regs->psw.addr);	printk("%s GPRS: %08x %08x %08x %08x\n", mode,	       regs->gprs[0], regs->gprs[1], regs->gprs[2], regs->gprs[3]);	printk("           %08x %08x %08x %08x\n",	       regs->gprs[4], regs->gprs[5], regs->gprs[6], regs->gprs[7]);	printk("           %08x %08x %08x %08x\n",	       regs->gprs[8], regs->gprs[9], regs->gprs[10], regs->gprs[11]);	printk("           %08x %08x %08x %08x\n",	       regs->gprs[12], regs->gprs[13], regs->gprs[14], regs->gprs[15]);	printk("%s ACRS: %08x %08x %08x %08x\n", mode,	       regs->acrs[0], regs->acrs[1], regs->acrs[2], regs->acrs[3]);	printk("           %08x %08x %08x %08x\n",	       regs->acrs[4], regs->acrs[5], regs->acrs[6], regs->acrs[7]);	printk("           %08x %08x %08x %08x\n",	       regs->acrs[8], regs->acrs[9], regs->acrs[10], regs->acrs[11]);	printk("           %08x %08x %08x %08x\n",	       regs->acrs[12], regs->acrs[13], regs->acrs[14], regs->acrs[15]);	/*	 * Print the first 20 byte of the instruction stream at the	 * time of the fault.	 */	old_fs = get_fs();	if (regs->psw.mask & PSW_PROBLEM_STATE)		set_fs(USER_DS);	else		set_fs(KERNEL_DS);	printk("%s Code: ", mode);	for (i = 0; i < 20; i++) {		unsigned char c;		if (__get_user(c, (char *)(regs->psw.addr + i))) {			printk(" Bad PSW.");			break;		}		printk("%02x ", c);	}	set_fs(old_fs);	printk("\n");}	/* This is called from fs/proc/array.c */char *task_show_regs(struct task_struct *task, char *buffer){	struct pt_regs *regs;	regs = __KSTK_PTREGS(task);	buffer += sprintf(buffer, "task: %08lx, ksp: %08x\n",			  (unsigned long) task, task->thread.ksp);	buffer += sprintf(buffer, "User PSW : %08lx %08lx\n",			  (unsigned long) regs->psw.mask, 			  (unsigned long) regs->psw.addr);	buffer += sprintf(buffer, "User GPRS: %08x %08x %08x %08x\n",			  regs->gprs[0], regs->gprs[1],			  regs->gprs[2], regs->gprs[3]);	buffer += sprintf(buffer, "           %08x %08x %08x %08x\n",			  regs->gprs[4], regs->gprs[5],			  regs->gprs[6], regs->gprs[7]);	buffer += sprintf(buffer, "           %08x %08x %08x %08x\n",			  regs->gprs[8], regs->gprs[9],			  regs->gprs[10], regs->gprs[11]);	buffer += sprintf(buffer, "           %08x %08x %08x %08x\n",			  regs->gprs[12], regs->gprs[13],			  regs->gprs[14], regs->gprs[15]);	buffer += sprintf(buffer, "User ACRS: %08x %08x %08x %08x\n",			  regs->acrs[0], regs->acrs[1],			  regs->acrs[2], regs->acrs[3]);	buffer += sprintf(buffer, "           %08x %08x %08x %08x\n",			  regs->acrs[4], regs->acrs[5],			  regs->acrs[6], regs->acrs[7]);	buffer += sprintf(buffer, "           %08x %08x %08x %08x\n",			  regs->acrs[8], regs->acrs[9],			  regs->acrs[10], regs->acrs[11]);	buffer += sprintf(buffer, "           %08x %08x %08x %08x\n",			  regs->acrs[12], regs->acrs[13],			  regs->acrs[14], regs->acrs[15]);	return buffer;}spinlock_t die_lock = SPIN_LOCK_UNLOCKED;void die(const char * str, struct pt_regs * regs, long err){        console_verbose();        spin_lock_irq(&die_lock);	bust_spinlocks(1);        printk("%s: %04lx\n", str, err & 0xffff);        show_regs(regs);	bust_spinlocks(0);        spin_unlock_irq(&die_lock);        do_exit(SIGSEGV);}static void inline do_trap(long interruption_code, int signr, char *str,                           struct pt_regs *regs, siginfo_t *info){	/*	 * We got all needed information from the lowcore and can	 * now safely switch on interrupts.	 */        if (regs->psw.mask & PSW_PROBLEM_STATE)		__sti();        if (regs->psw.mask & PSW_PROBLEM_STATE) {                struct task_struct *tsk = current;                tsk->thread.trap_no = interruption_code & 0xffff;		if (info)			force_sig_info(signr, info, tsk);		else                	force_sig(signr, tsk);#ifndef CONFIG_SYSCTL#ifdef CONFIG_PROCESS_DEBUG                printk("User process fault: interruption code 0x%lX\n",                       interruption_code);                show_regs(regs);#endif#else		if (sysctl_userprocess_debug) {			printk("User process fault: interruption code 0x%lX\n",			       interruption_code);			show_regs(regs);		}#endif        } else {                unsigned long fixup = search_exception_table(regs->psw.addr);                if (fixup)                        regs->psw.addr = fixup;                else                        die(str, regs, interruption_code);        }}static inline void *get_check_address(struct pt_regs *regs){	return (void *) ADDR_BITS_REMOVE(regs->psw.addr-S390_lowcore.pgm_ilc);}int do_debugger_trap(struct pt_regs *regs,int signal){	if(regs->psw.mask&PSW_PROBLEM_STATE)	{		if(current->ptrace & PT_PTRACED)			force_sig(signal,current);		else			return 1;	}	else	{#if CONFIG_REMOTE_DEBUG		if(gdb_stub_initialised)		{			gdb_stub_handle_exception(regs, signal);			return 0;		}#endif		return 1;	}	return 0;}#define DO_ERROR(signr, str, name) \asmlinkage void name(struct pt_regs * regs, long interruption_code) \{ \	do_trap(interruption_code, signr, str, regs, NULL); \