115 lines
		
	
	
		
			2.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			115 lines
		
	
	
		
			2.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| #include <linux/bug.h>
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| #include <linux/io.h>
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| #include <linux/types.h>
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| #include <linux/kdebug.h>
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| #include <linux/signal.h>
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| #include <linux/sched.h>
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| #include <linux/uaccess.h>
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| #include <linux/hardirq.h>
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| #include <asm/unwinder.h>
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| #include <asm/system.h>
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| 
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| #ifdef CONFIG_BUG
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| void handle_BUG(struct pt_regs *regs)
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| {
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| 	const struct bug_entry *bug;
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| 	unsigned long bugaddr = regs->pc;
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| 	enum bug_trap_type tt;
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| 
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| 	if (!is_valid_bugaddr(bugaddr))
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| 		goto invalid;
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| 
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| 	bug = find_bug(bugaddr);
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| 
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| 	/* Switch unwinders when unwind_stack() is called */
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| 	if (bug->flags & BUGFLAG_UNWINDER)
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| 		unwinder_faulted = 1;
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| 
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| 	tt = report_bug(bugaddr, regs);
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| 	if (tt == BUG_TRAP_TYPE_WARN) {
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| 		regs->pc += instruction_size(bugaddr);
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| 		return;
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| 	}
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| 
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| invalid:
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| 	die("Kernel BUG", regs, TRAPA_BUG_OPCODE & 0xff);
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| }
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| 
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| int is_valid_bugaddr(unsigned long addr)
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| {
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| 	insn_size_t opcode;
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| 
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| 	if (addr < PAGE_OFFSET)
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| 		return 0;
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| 	if (probe_kernel_address((insn_size_t *)addr, opcode))
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| 		return 0;
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| 	if (opcode == TRAPA_BUG_OPCODE)
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| 		return 1;
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| 
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| 	return 0;
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| }
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| #endif
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| 
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| /*
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|  * Generic trap handler.
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|  */
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| BUILD_TRAP_HANDLER(debug)
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| {
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| 	TRAP_HANDLER_DECL;
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| 
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| 	/* Rewind */
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| 	regs->pc -= instruction_size(ctrl_inw(regs->pc - 4));
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| 
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| 	if (notify_die(DIE_TRAP, "debug trap", regs, 0, vec & 0xff,
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| 		       SIGTRAP) == NOTIFY_STOP)
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| 		return;
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| 
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| 	force_sig(SIGTRAP, current);
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| }
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| 
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| /*
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|  * Special handler for BUG() traps.
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|  */
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| BUILD_TRAP_HANDLER(bug)
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| {
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| 	TRAP_HANDLER_DECL;
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| 
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| 	/* Rewind */
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| 	regs->pc -= instruction_size(ctrl_inw(regs->pc - 4));
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| 
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| 	if (notify_die(DIE_TRAP, "bug trap", regs, 0, TRAPA_BUG_OPCODE & 0xff,
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| 		       SIGTRAP) == NOTIFY_STOP)
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| 		return;
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| 
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| #ifdef CONFIG_BUG
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| 	if (__kernel_text_address(instruction_pointer(regs))) {
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| 		insn_size_t insn = *(insn_size_t *)instruction_pointer(regs);
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| 		if (insn == TRAPA_BUG_OPCODE)
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| 			handle_BUG(regs);
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| 		return;
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| 	}
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| #endif
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| 
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| 	force_sig(SIGTRAP, current);
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| }
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| 
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| BUILD_TRAP_HANDLER(nmi)
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| {
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| 	TRAP_HANDLER_DECL;
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| 
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| 	nmi_enter();
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| 
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| 	switch (notify_die(DIE_NMI, "NMI", regs, 0, vec & 0xff, SIGINT)) {
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| 	case NOTIFY_OK:
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| 	case NOTIFY_STOP:
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| 		break;
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| 	case NOTIFY_BAD:
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| 		die("Fatal Non-Maskable Interrupt", regs, SIGINT);
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| 	default:
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| 		printk(KERN_ALERT "Got NMI, but nobody cared. Ignoring...\n");
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| 		break;
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| 	}
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| 
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| 	nmi_exit();
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| }
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