 196779b9b4
			
		
	
	
	196779b9b4
	
	
	
		
			
			Both dump_stack() and show_stack() are currently implemented by each architecture. show_stack(NULL, NULL) dumps the backtrace for the current task as does dump_stack(). On some archs, dump_stack() prints extra information - pid, utsname and so on - in addition to the backtrace while the two are identical on other archs. The usages in arch-independent code of the two functions indicate show_stack(NULL, NULL) should print out bare backtrace while dump_stack() is used for debugging purposes when something went wrong, so it does make sense to print additional information on the task which triggered dump_stack(). There's no reason to require archs to implement two separate but mostly identical functions. It leads to unnecessary subtle information. This patch expands the dummy fallback dump_stack() implementation in lib/dump_stack.c such that it prints out debug information (taken from x86) and invokes show_stack(NULL, NULL) and drops arch-specific dump_stack() implementations in all archs except blackfin. Blackfin's dump_stack() does something wonky that I don't understand. Debug information can be printed separately by calling dump_stack_print_info() so that arch-specific dump_stack() implementation can still emit the same debug information. This is used in blackfin. This patch brings the following behavior changes. * On some archs, an extra level in backtrace for show_stack() could be printed. This is because the top frame was determined in dump_stack() on those archs while generic dump_stack() can't do that reliably. It can be compensated by inlining dump_stack() but not sure whether that'd be necessary. * Most archs didn't use to print debug info on dump_stack(). They do now. An example WARN dump follows. WARNING: at kernel/workqueue.c:4841 init_workqueues+0x35/0x505() Hardware name: empty Modules linked in: CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.9.0-rc1-work+ #9 0000000000000009 ffff88007c861e08 ffffffff81c614dc ffff88007c861e48 ffffffff8108f50f ffffffff82228240 0000000000000040 ffffffff8234a03c 0000000000000000 0000000000000000 0000000000000000 ffff88007c861e58 Call Trace: [<ffffffff81c614dc>] dump_stack+0x19/0x1b [<ffffffff8108f50f>] warn_slowpath_common+0x7f/0xc0 [<ffffffff8108f56a>] warn_slowpath_null+0x1a/0x20 [<ffffffff8234a071>] init_workqueues+0x35/0x505 ... v2: CPU number added to the generic debug info as requested by s390 folks and dropped the s390 specific dump_stack(). This loses %ksp from the debug message which the maintainers think isn't important enough to keep the s390-specific dump_stack() implementation. dump_stack_print_info() is moved to kernel/printk.c from lib/dump_stack.c. Because linkage is per objecct file, dump_stack_print_info() living in the same lib file as generic dump_stack() means that archs which implement custom dump_stack() - at this point, only blackfin - can't use dump_stack_print_info() as that will bring in the generic version of dump_stack() too. v1 The v1 patch broke build on blackfin due to this issue. The build breakage was reported by Fengguang Wu. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: David S. Miller <davem@davemloft.net> Acked-by: Vineet Gupta <vgupta@synopsys.com> Acked-by: Jesper Nilsson <jesper.nilsson@axis.com> Acked-by: Vineet Gupta <vgupta@synopsys.com> Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com> [s390 bits] Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Mike Frysinger <vapier@gentoo.org> Cc: Fengguang Wu <fengguang.wu@intel.com> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Sam Ravnborg <sam@ravnborg.org> Acked-by: Richard Kuo <rkuo@codeaurora.org> [hexagon bits] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
		
			
				
	
	
		
			355 lines
		
	
	
	
		
			9.4 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			355 lines
		
	
	
	
		
			9.4 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * OpenRISC traps.c
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|  *
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|  * Linux architectural port borrowing liberally from similar works of
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|  * others.  All original copyrights apply as per the original source
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|  * declaration.
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|  *
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|  * Modifications for the OpenRISC architecture:
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|  * Copyright (C) 2003 Matjaz Breskvar <phoenix@bsemi.com>
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|  * Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se>
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|  *
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|  *      This program is free software; you can redistribute it and/or
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|  *      modify it under the terms of the GNU General Public License
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|  *      as published by the Free Software Foundation; either version
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|  *      2 of the License, or (at your option) any later version.
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|  *
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|  *  Here we handle the break vectors not used by the system call
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|  *  mechanism, as well as some general stack/register dumping
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|  *  things.
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|  *
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|  */
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| 
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| #include <linux/init.h>
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| #include <linux/sched.h>
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| #include <linux/kernel.h>
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| #include <linux/module.h>
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| #include <linux/kmod.h>
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| #include <linux/string.h>
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| #include <linux/errno.h>
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| #include <linux/ptrace.h>
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| #include <linux/timer.h>
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| #include <linux/mm.h>
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| #include <linux/kallsyms.h>
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| #include <asm/uaccess.h>
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| 
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| #include <asm/segment.h>
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| #include <asm/io.h>
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| #include <asm/pgtable.h>
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| 
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| extern char _etext, _stext;
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| 
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| int kstack_depth_to_print = 0x180;
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| 
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| static inline int valid_stack_ptr(struct thread_info *tinfo, void *p)
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| {
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| 	return p > (void *)tinfo && p < (void *)tinfo + THREAD_SIZE - 3;
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| }
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| 
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| void show_trace(struct task_struct *task, unsigned long *stack)
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| {
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| 	struct thread_info *context;
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| 	unsigned long addr;
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| 
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| 	context = (struct thread_info *)
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| 	    ((unsigned long)stack & (~(THREAD_SIZE - 1)));
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| 
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| 	while (valid_stack_ptr(context, stack)) {
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| 		addr = *stack++;
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| 		if (__kernel_text_address(addr)) {
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| 			printk(" [<%08lx>]", addr);
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| 			print_symbol(" %s", addr);
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| 			printk("\n");
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| 		}
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| 	}
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| 	printk(" =======================\n");
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| }
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| 
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| /* displays a short stack trace */
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| void show_stack(struct task_struct *task, unsigned long *esp)
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| {
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| 	unsigned long addr, *stack;
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| 	int i;
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| 
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| 	if (esp == NULL)
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| 		esp = (unsigned long *)&esp;
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| 
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| 	stack = esp;
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| 
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| 	printk("Stack dump [0x%08lx]:\n", (unsigned long)esp);
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| 	for (i = 0; i < kstack_depth_to_print; i++) {
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| 		if (kstack_end(stack))
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| 			break;
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| 		if (__get_user(addr, stack)) {
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| 			/* This message matches "failing address" marked
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| 			   s390 in ksymoops, so lines containing it will
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| 			   not be filtered out by ksymoops.  */
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| 			printk("Failing address 0x%lx\n", (unsigned long)stack);
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| 			break;
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| 		}
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| 		stack++;
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| 
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| 		printk("sp + %02d: 0x%08lx\n", i * 4, addr);
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| 	}
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| 	printk("\n");
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| 
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| 	show_trace(task, esp);
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| 
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| 	return;
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| }
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| 
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| void show_trace_task(struct task_struct *tsk)
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| {
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| 	/*
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| 	 * TODO: SysRq-T trace dump...
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| 	 */
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| }
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| 
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| void show_registers(struct pt_regs *regs)
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| {
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| 	int i;
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| 	int in_kernel = 1;
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| 	unsigned long esp;
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| 
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| 	esp = (unsigned long)(®s->sp);
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| 	if (user_mode(regs))
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| 		in_kernel = 0;
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| 
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| 	printk("CPU #: %d\n"
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| 	       "   PC: %08lx    SR: %08lx    SP: %08lx\n",
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| 	       smp_processor_id(), regs->pc, regs->sr, regs->sp);
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| 	printk("GPR00: %08lx GPR01: %08lx GPR02: %08lx GPR03: %08lx\n",
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| 	       0L, regs->gpr[1], regs->gpr[2], regs->gpr[3]);
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| 	printk("GPR04: %08lx GPR05: %08lx GPR06: %08lx GPR07: %08lx\n",
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| 	       regs->gpr[4], regs->gpr[5], regs->gpr[6], regs->gpr[7]);
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| 	printk("GPR08: %08lx GPR09: %08lx GPR10: %08lx GPR11: %08lx\n",
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| 	       regs->gpr[8], regs->gpr[9], regs->gpr[10], regs->gpr[11]);
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| 	printk("GPR12: %08lx GPR13: %08lx GPR14: %08lx GPR15: %08lx\n",
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| 	       regs->gpr[12], regs->gpr[13], regs->gpr[14], regs->gpr[15]);
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| 	printk("GPR16: %08lx GPR17: %08lx GPR18: %08lx GPR19: %08lx\n",
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| 	       regs->gpr[16], regs->gpr[17], regs->gpr[18], regs->gpr[19]);
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| 	printk("GPR20: %08lx GPR21: %08lx GPR22: %08lx GPR23: %08lx\n",
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| 	       regs->gpr[20], regs->gpr[21], regs->gpr[22], regs->gpr[23]);
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| 	printk("GPR24: %08lx GPR25: %08lx GPR26: %08lx GPR27: %08lx\n",
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| 	       regs->gpr[24], regs->gpr[25], regs->gpr[26], regs->gpr[27]);
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| 	printk("GPR28: %08lx GPR29: %08lx GPR30: %08lx GPR31: %08lx\n",
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| 	       regs->gpr[28], regs->gpr[29], regs->gpr[30], regs->gpr[31]);
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| 	printk("  RES: %08lx oGPR11: %08lx\n",
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| 	       regs->gpr[11], regs->orig_gpr11);
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| 
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| 	printk("Process %s (pid: %d, stackpage=%08lx)\n",
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| 	       current->comm, current->pid, (unsigned long)current);
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| 	/*
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| 	 * When in-kernel, we also print out the stack and code at the
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| 	 * time of the fault..
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| 	 */
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| 	if (in_kernel) {
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| 
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| 		printk("\nStack: ");
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| 		show_stack(NULL, (unsigned long *)esp);
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| 
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| 		printk("\nCode: ");
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| 		if (regs->pc < PAGE_OFFSET)
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| 			goto bad;
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| 
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| 		for (i = -24; i < 24; i++) {
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| 			unsigned char c;
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| 			if (__get_user(c, &((unsigned char *)regs->pc)[i])) {
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| bad:
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| 				printk(" Bad PC value.");
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| 				break;
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| 			}
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| 
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| 			if (i == 0)
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| 				printk("(%02x) ", c);
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| 			else
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| 				printk("%02x ", c);
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| 		}
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| 	}
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| 	printk("\n");
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| }
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| 
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| void nommu_dump_state(struct pt_regs *regs,
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| 		      unsigned long ea, unsigned long vector)
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| {
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| 	int i;
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| 	unsigned long addr, stack = regs->sp;
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| 
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| 	printk("\n\r[nommu_dump_state] :: ea %lx, vector %lx\n\r", ea, vector);
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| 
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| 	printk("CPU #: %d\n"
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| 	       "   PC: %08lx    SR: %08lx    SP: %08lx\n",
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| 	       0, regs->pc, regs->sr, regs->sp);
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| 	printk("GPR00: %08lx GPR01: %08lx GPR02: %08lx GPR03: %08lx\n",
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| 	       0L, regs->gpr[1], regs->gpr[2], regs->gpr[3]);
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| 	printk("GPR04: %08lx GPR05: %08lx GPR06: %08lx GPR07: %08lx\n",
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| 	       regs->gpr[4], regs->gpr[5], regs->gpr[6], regs->gpr[7]);
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| 	printk("GPR08: %08lx GPR09: %08lx GPR10: %08lx GPR11: %08lx\n",
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| 	       regs->gpr[8], regs->gpr[9], regs->gpr[10], regs->gpr[11]);
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| 	printk("GPR12: %08lx GPR13: %08lx GPR14: %08lx GPR15: %08lx\n",
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| 	       regs->gpr[12], regs->gpr[13], regs->gpr[14], regs->gpr[15]);
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| 	printk("GPR16: %08lx GPR17: %08lx GPR18: %08lx GPR19: %08lx\n",
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| 	       regs->gpr[16], regs->gpr[17], regs->gpr[18], regs->gpr[19]);
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| 	printk("GPR20: %08lx GPR21: %08lx GPR22: %08lx GPR23: %08lx\n",
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| 	       regs->gpr[20], regs->gpr[21], regs->gpr[22], regs->gpr[23]);
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| 	printk("GPR24: %08lx GPR25: %08lx GPR26: %08lx GPR27: %08lx\n",
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| 	       regs->gpr[24], regs->gpr[25], regs->gpr[26], regs->gpr[27]);
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| 	printk("GPR28: %08lx GPR29: %08lx GPR30: %08lx GPR31: %08lx\n",
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| 	       regs->gpr[28], regs->gpr[29], regs->gpr[30], regs->gpr[31]);
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| 	printk("  RES: %08lx oGPR11: %08lx\n",
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| 	       regs->gpr[11], regs->orig_gpr11);
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| 
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| 	printk("Process %s (pid: %d, stackpage=%08lx)\n",
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| 	       ((struct task_struct *)(__pa(current)))->comm,
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| 	       ((struct task_struct *)(__pa(current)))->pid,
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| 	       (unsigned long)current);
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| 
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| 	printk("\nStack: ");
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| 	printk("Stack dump [0x%08lx]:\n", (unsigned long)stack);
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| 	for (i = 0; i < kstack_depth_to_print; i++) {
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| 		if (((long)stack & (THREAD_SIZE - 1)) == 0)
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| 			break;
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| 		stack++;
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| 
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| 		printk("%lx :: sp + %02d: 0x%08lx\n", stack, i * 4,
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| 		       *((unsigned long *)(__pa(stack))));
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| 	}
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| 	printk("\n");
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| 
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| 	printk("Call Trace:   ");
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| 	i = 1;
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| 	while (((long)stack & (THREAD_SIZE - 1)) != 0) {
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| 		addr = *((unsigned long *)__pa(stack));
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| 		stack++;
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| 
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| 		if (kernel_text_address(addr)) {
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| 			if (i && ((i % 6) == 0))
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| 				printk("\n ");
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| 			printk(" [<%08lx>]", addr);
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| 			i++;
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| 		}
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| 	}
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| 	printk("\n");
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| 
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| 	printk("\nCode: ");
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| 
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| 	for (i = -24; i < 24; i++) {
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| 		unsigned char c;
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| 		c = ((unsigned char *)(__pa(regs->pc)))[i];
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| 
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| 		if (i == 0)
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| 			printk("(%02x) ", c);
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| 		else
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| 			printk("%02x ", c);
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| 	}
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| 	printk("\n");
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| }
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| 
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| /* This is normally the 'Oops' routine */
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| void die(const char *str, struct pt_regs *regs, long err)
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| {
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| 
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| 	console_verbose();
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| 	printk("\n%s#: %04lx\n", str, err & 0xffff);
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| 	show_registers(regs);
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| #ifdef CONFIG_JUMP_UPON_UNHANDLED_EXCEPTION
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| 	printk("\n\nUNHANDLED_EXCEPTION: entering infinite loop\n");
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| 
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| 	/* shut down interrupts */
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| 	local_irq_disable();
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| 
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| 	__asm__ __volatile__("l.nop   1");
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| 	do {} while (1);
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| #endif
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| 	do_exit(SIGSEGV);
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| }
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| 
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| /* This is normally the 'Oops' routine */
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| void die_if_kernel(const char *str, struct pt_regs *regs, long err)
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| {
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| 	if (user_mode(regs))
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| 		return;
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| 
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| 	die(str, regs, err);
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| }
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| 
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| void unhandled_exception(struct pt_regs *regs, int ea, int vector)
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| {
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| 	printk("Unable to handle exception at EA =0x%x, vector 0x%x",
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| 	       ea, vector);
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| 	die("Oops", regs, 9);
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| }
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| 
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| void __init trap_init(void)
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| {
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| 	/* Nothing needs to be done */
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| }
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| 
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| asmlinkage void do_trap(struct pt_regs *regs, unsigned long address)
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| {
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| 	siginfo_t info;
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| 	memset(&info, 0, sizeof(info));
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| 	info.si_signo = SIGTRAP;
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| 	info.si_code = TRAP_TRACE;
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| 	info.si_addr = (void *)address;
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| 	force_sig_info(SIGTRAP, &info, current);
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| 
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| 	regs->pc += 4;
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| }
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| 
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| asmlinkage void do_unaligned_access(struct pt_regs *regs, unsigned long address)
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| {
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| 	siginfo_t info;
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| 
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| 	if (user_mode(regs)) {
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| 		/* Send a SIGSEGV */
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| 		info.si_signo = SIGSEGV;
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| 		info.si_errno = 0;
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| 		/* info.si_code has been set above */
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| 		info.si_addr = (void *)address;
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| 		force_sig_info(SIGSEGV, &info, current);
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| 	} else {
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| 		printk("KERNEL: Unaligned Access 0x%.8lx\n", address);
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| 		show_registers(regs);
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| 		die("Die:", regs, address);
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| 	}
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| 
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| }
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| 
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| asmlinkage void do_bus_fault(struct pt_regs *regs, unsigned long address)
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| {
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| 	siginfo_t info;
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| 
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| 	if (user_mode(regs)) {
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| 		/* Send a SIGBUS */
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| 		info.si_signo = SIGBUS;
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| 		info.si_errno = 0;
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| 		info.si_code = BUS_ADRERR;
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| 		info.si_addr = (void *)address;
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| 		force_sig_info(SIGBUS, &info, current);
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| 	} else {		/* Kernel mode */
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| 		printk("KERNEL: Bus error (SIGBUS) 0x%.8lx\n", address);
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| 		show_registers(regs);
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| 		die("Die:", regs, address);
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| 	}
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| }
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| 
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| asmlinkage void do_illegal_instruction(struct pt_regs *regs,
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| 				       unsigned long address)
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| {
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| 	siginfo_t info;
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| 
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| 	if (user_mode(regs)) {
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| 		/* Send a SIGILL */
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| 		info.si_signo = SIGILL;
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| 		info.si_errno = 0;
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| 		info.si_code = ILL_ILLOPC;
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| 		info.si_addr = (void *)address;
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| 		force_sig_info(SIGBUS, &info, current);
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| 	} else {		/* Kernel mode */
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| 		printk("KERNEL: Illegal instruction (SIGILL) 0x%.8lx\n",
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| 		       address);
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| 		show_registers(regs);
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| 		die("Die:", regs, address);
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| 	}
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| }
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