99 lines
		
	
	
		
			2.5 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			99 lines
		
	
	
		
			2.5 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * arch/s390/kernel/stacktrace.c
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|  *
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|  * Stack trace management functions
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|  *
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|  *  Copyright (C) IBM Corp. 2006
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|  *  Author(s): Heiko Carstens <heiko.carstens@de.ibm.com>
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|  */
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| 
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| #include <linux/sched.h>
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| #include <linux/stacktrace.h>
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| #include <linux/kallsyms.h>
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| #include <linux/module.h>
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| 
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| static unsigned long save_context_stack(struct stack_trace *trace,
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| 					unsigned long sp,
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| 					unsigned long low,
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| 					unsigned long high,
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| 					int savesched)
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| {
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| 	struct stack_frame *sf;
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| 	struct pt_regs *regs;
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| 	unsigned long addr;
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| 
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| 	while(1) {
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| 		sp &= PSW_ADDR_INSN;
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| 		if (sp < low || sp > high)
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| 			return sp;
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| 		sf = (struct stack_frame *)sp;
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| 		while(1) {
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| 			addr = sf->gprs[8] & PSW_ADDR_INSN;
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| 			if (!trace->skip)
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| 				trace->entries[trace->nr_entries++] = addr;
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| 			else
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| 				trace->skip--;
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| 			if (trace->nr_entries >= trace->max_entries)
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| 				return sp;
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| 			low = sp;
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| 			sp = sf->back_chain & PSW_ADDR_INSN;
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| 			if (!sp)
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| 				break;
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| 			if (sp <= low || sp > high - sizeof(*sf))
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| 				return sp;
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| 			sf = (struct stack_frame *)sp;
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| 		}
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| 		/* Zero backchain detected, check for interrupt frame. */
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| 		sp = (unsigned long)(sf + 1);
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| 		if (sp <= low || sp > high - sizeof(*regs))
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| 			return sp;
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| 		regs = (struct pt_regs *)sp;
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| 		addr = regs->psw.addr & PSW_ADDR_INSN;
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| 		if (savesched || !in_sched_functions(addr)) {
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| 			if (!trace->skip)
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| 				trace->entries[trace->nr_entries++] = addr;
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| 			else
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| 				trace->skip--;
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| 		}
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| 		if (trace->nr_entries >= trace->max_entries)
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| 			return sp;
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| 		low = sp;
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| 		sp = regs->gprs[15];
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| 	}
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| }
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| 
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| void save_stack_trace(struct stack_trace *trace)
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| {
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| 	register unsigned long sp asm ("15");
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| 	unsigned long orig_sp, new_sp;
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| 
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| 	orig_sp = sp & PSW_ADDR_INSN;
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| 	new_sp = save_context_stack(trace, orig_sp,
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| 				    S390_lowcore.panic_stack - PAGE_SIZE,
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| 				    S390_lowcore.panic_stack, 1);
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| 	if (new_sp != orig_sp)
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| 		return;
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| 	new_sp = save_context_stack(trace, new_sp,
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| 				    S390_lowcore.async_stack - ASYNC_SIZE,
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| 				    S390_lowcore.async_stack, 1);
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| 	if (new_sp != orig_sp)
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| 		return;
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| 	save_context_stack(trace, new_sp,
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| 			   S390_lowcore.thread_info,
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| 			   S390_lowcore.thread_info + THREAD_SIZE, 1);
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| }
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| EXPORT_SYMBOL_GPL(save_stack_trace);
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| 
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| void save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace)
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| {
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| 	unsigned long sp, low, high;
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| 
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| 	sp = tsk->thread.ksp & PSW_ADDR_INSN;
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| 	low = (unsigned long) task_stack_page(tsk);
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| 	high = (unsigned long) task_pt_regs(tsk);
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| 	save_context_stack(trace, sp, low, high, 0);
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| 	if (trace->nr_entries < trace->max_entries)
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| 		trace->entries[trace->nr_entries++] = ULONG_MAX;
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| }
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| EXPORT_SYMBOL_GPL(save_stack_trace_tsk);
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