When printing the code bytes in show_registers(), the markers around the byte at the fault address could make the printk() format string look like a valid log level and facility code. This would prevent this byte from being printed and result in a spurious newline: [ 7555.765589] Code: 8b 32 e9 94 00 00 00 81 7d 00 ff 00 00 00 0f 87 96 00 00 00 48 8b 83 c0 00 00 00 44 89 e2 44 89 e6 48 89 df 48 8b 80 d8 02 00 00 [ 7555.765683] 8b 48 28 48 89 d0 81 e2 ff 0f 00 00 48 c1 e8 0c 48 c1 e0 04 Add KERN_CONT where needed, and elsewhere in show_registers() for consistency. Signed-off-by: Clemens Ladisch <clemens@ladisch.de> Link: http://lkml.kernel.org/r/4EEFA7AE.9020407@ladisch.de Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
		
			
				
	
	
		
			141 lines
		
	
	
	
		
			3.1 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			141 lines
		
	
	
	
		
			3.1 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
/*
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 *  Copyright (C) 1991, 1992  Linus Torvalds
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 *  Copyright (C) 2000, 2001, 2002 Andi Kleen, SuSE Labs
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 */
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#include <linux/kallsyms.h>
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#include <linux/kprobes.h>
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#include <linux/uaccess.h>
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#include <linux/hardirq.h>
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#include <linux/kdebug.h>
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#include <linux/module.h>
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#include <linux/ptrace.h>
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#include <linux/kexec.h>
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#include <linux/sysfs.h>
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#include <linux/bug.h>
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#include <linux/nmi.h>
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#include <asm/stacktrace.h>
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void dump_trace(struct task_struct *task, struct pt_regs *regs,
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		unsigned long *stack, unsigned long bp,
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		const struct stacktrace_ops *ops, void *data)
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{
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	int graph = 0;
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	if (!task)
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		task = current;
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	if (!stack) {
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		unsigned long dummy;
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		stack = &dummy;
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		if (task && task != current)
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			stack = (unsigned long *)task->thread.sp;
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	}
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	if (!bp)
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		bp = stack_frame(task, regs);
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	for (;;) {
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		struct thread_info *context;
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		context = (struct thread_info *)
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			((unsigned long)stack & (~(THREAD_SIZE - 1)));
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		bp = ops->walk_stack(context, stack, bp, ops, data, NULL, &graph);
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		stack = (unsigned long *)context->previous_esp;
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		if (!stack)
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			break;
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		if (ops->stack(data, "IRQ") < 0)
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			break;
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		touch_nmi_watchdog();
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	}
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}
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EXPORT_SYMBOL(dump_trace);
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void
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show_stack_log_lvl(struct task_struct *task, struct pt_regs *regs,
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		   unsigned long *sp, unsigned long bp, char *log_lvl)
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{
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	unsigned long *stack;
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	int i;
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	if (sp == NULL) {
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		if (task)
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			sp = (unsigned long *)task->thread.sp;
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		else
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			sp = (unsigned long *)&sp;
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	}
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	stack = sp;
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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 (i && ((i % STACKSLOTS_PER_LINE) == 0))
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			printk(KERN_CONT "\n");
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		printk(KERN_CONT " %08lx", *stack++);
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		touch_nmi_watchdog();
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	}
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	printk(KERN_CONT "\n");
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	show_trace_log_lvl(task, regs, sp, bp, log_lvl);
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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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	print_modules();
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	__show_regs(regs, 0);
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	printk(KERN_EMERG "Process %.*s (pid: %d, ti=%p task=%p task.ti=%p)\n",
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		TASK_COMM_LEN, current->comm, task_pid_nr(current),
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		current_thread_info(), current, task_thread_info(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 (!user_mode_vm(regs)) {
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		unsigned int code_prologue = code_bytes * 43 / 64;
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		unsigned int code_len = code_bytes;
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		unsigned char c;
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		u8 *ip;
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		printk(KERN_EMERG "Stack:\n");
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		show_stack_log_lvl(NULL, regs, ®s->sp, 0, KERN_EMERG);
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		printk(KERN_EMERG "Code: ");
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		ip = (u8 *)regs->ip - code_prologue;
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		if (ip < (u8 *)PAGE_OFFSET || probe_kernel_address(ip, c)) {
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			/* try starting at IP */
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			ip = (u8 *)regs->ip;
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			code_len = code_len - code_prologue + 1;
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		}
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		for (i = 0; i < code_len; i++, ip++) {
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			if (ip < (u8 *)PAGE_OFFSET ||
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					probe_kernel_address(ip, c)) {
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				printk(KERN_CONT " Bad EIP value.");
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				break;
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			}
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			if (ip == (u8 *)regs->ip)
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				printk(KERN_CONT "<%02x> ", c);
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			else
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				printk(KERN_CONT "%02x ", c);
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		}
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	}
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	printk(KERN_CONT "\n");
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}
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int is_valid_bugaddr(unsigned long ip)
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{
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	unsigned short ud2;
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	if (ip < PAGE_OFFSET)
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		return 0;
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	if (probe_kernel_address((unsigned short *)ip, ud2))
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		return 0;
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	return ud2 == 0x0b0f;
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}
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