xref: /openbmc/linux/arch/openrisc/kernel/traps.c (revision 9ffc93f2)
1 /*
2  * OpenRISC traps.c
3  *
4  * Linux architectural port borrowing liberally from similar works of
5  * others.  All original copyrights apply as per the original source
6  * declaration.
7  *
8  * Modifications for the OpenRISC architecture:
9  * Copyright (C) 2003 Matjaz Breskvar <phoenix@bsemi.com>
10  * Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se>
11  *
12  *      This program is free software; you can redistribute it and/or
13  *      modify it under the terms of the GNU General Public License
14  *      as published by the Free Software Foundation; either version
15  *      2 of the License, or (at your option) any later version.
16  *
17  *  Here we handle the break vectors not used by the system call
18  *  mechanism, as well as some general stack/register dumping
19  *  things.
20  *
21  */
22 
23 #include <linux/init.h>
24 #include <linux/sched.h>
25 #include <linux/kernel.h>
26 #include <linux/module.h>
27 #include <linux/kmod.h>
28 #include <linux/string.h>
29 #include <linux/errno.h>
30 #include <linux/ptrace.h>
31 #include <linux/timer.h>
32 #include <linux/mm.h>
33 #include <linux/kallsyms.h>
34 #include <asm/uaccess.h>
35 
36 #include <asm/segment.h>
37 #include <asm/io.h>
38 #include <asm/pgtable.h>
39 
40 extern char _etext, _stext;
41 
42 int kstack_depth_to_print = 0x180;
43 
44 static inline int valid_stack_ptr(struct thread_info *tinfo, void *p)
45 {
46 	return p > (void *)tinfo && p < (void *)tinfo + THREAD_SIZE - 3;
47 }
48 
49 void show_trace(struct task_struct *task, unsigned long *stack)
50 {
51 	struct thread_info *context;
52 	unsigned long addr;
53 
54 	context = (struct thread_info *)
55 	    ((unsigned long)stack & (~(THREAD_SIZE - 1)));
56 
57 	while (valid_stack_ptr(context, stack)) {
58 		addr = *stack++;
59 		if (__kernel_text_address(addr)) {
60 			printk(" [<%08lx>]", addr);
61 			print_symbol(" %s", addr);
62 			printk("\n");
63 		}
64 	}
65 	printk(" =======================\n");
66 }
67 
68 /* displays a short stack trace */
69 void show_stack(struct task_struct *task, unsigned long *esp)
70 {
71 	unsigned long addr, *stack;
72 	int i;
73 
74 	if (esp == NULL)
75 		esp = (unsigned long *)&esp;
76 
77 	stack = esp;
78 
79 	printk("Stack dump [0x%08lx]:\n", (unsigned long)esp);
80 	for (i = 0; i < kstack_depth_to_print; i++) {
81 		if (kstack_end(stack))
82 			break;
83 		if (__get_user(addr, stack)) {
84 			/* This message matches "failing address" marked
85 			   s390 in ksymoops, so lines containing it will
86 			   not be filtered out by ksymoops.  */
87 			printk("Failing address 0x%lx\n", (unsigned long)stack);
88 			break;
89 		}
90 		stack++;
91 
92 		printk("sp + %02d: 0x%08lx\n", i * 4, addr);
93 	}
94 	printk("\n");
95 
96 	show_trace(task, esp);
97 
98 	return;
99 }
100 
101 void show_trace_task(struct task_struct *tsk)
102 {
103 	/*
104 	 * TODO: SysRq-T trace dump...
105 	 */
106 }
107 
108 /*
109  * The architecture-independent backtrace generator
110  */
111 void dump_stack(void)
112 {
113 	unsigned long stack;
114 
115 	show_stack(current, &stack);
116 }
117 
118 void show_registers(struct pt_regs *regs)
119 {
120 	int i;
121 	int in_kernel = 1;
122 	unsigned long esp;
123 
124 	esp = (unsigned long)(&regs->sp);
125 	if (user_mode(regs))
126 		in_kernel = 0;
127 
128 	printk("CPU #: %d\n"
129 	       "   PC: %08lx    SR: %08lx    SP: %08lx\n",
130 	       smp_processor_id(), regs->pc, regs->sr, regs->sp);
131 	printk("GPR00: %08lx GPR01: %08lx GPR02: %08lx GPR03: %08lx\n",
132 	       0L, regs->gpr[1], regs->gpr[2], regs->gpr[3]);
133 	printk("GPR04: %08lx GPR05: %08lx GPR06: %08lx GPR07: %08lx\n",
134 	       regs->gpr[4], regs->gpr[5], regs->gpr[6], regs->gpr[7]);
135 	printk("GPR08: %08lx GPR09: %08lx GPR10: %08lx GPR11: %08lx\n",
136 	       regs->gpr[8], regs->gpr[9], regs->gpr[10], regs->gpr[11]);
137 	printk("GPR12: %08lx GPR13: %08lx GPR14: %08lx GPR15: %08lx\n",
138 	       regs->gpr[12], regs->gpr[13], regs->gpr[14], regs->gpr[15]);
139 	printk("GPR16: %08lx GPR17: %08lx GPR18: %08lx GPR19: %08lx\n",
140 	       regs->gpr[16], regs->gpr[17], regs->gpr[18], regs->gpr[19]);
141 	printk("GPR20: %08lx GPR21: %08lx GPR22: %08lx GPR23: %08lx\n",
142 	       regs->gpr[20], regs->gpr[21], regs->gpr[22], regs->gpr[23]);
143 	printk("GPR24: %08lx GPR25: %08lx GPR26: %08lx GPR27: %08lx\n",
144 	       regs->gpr[24], regs->gpr[25], regs->gpr[26], regs->gpr[27]);
145 	printk("GPR28: %08lx GPR29: %08lx GPR30: %08lx GPR31: %08lx\n",
146 	       regs->gpr[28], regs->gpr[29], regs->gpr[30], regs->gpr[31]);
147 	printk("  RES: %08lx oGPR11: %08lx syscallno: %08lx\n",
148 	       regs->gpr[11], regs->orig_gpr11, regs->syscallno);
149 
150 	printk("Process %s (pid: %d, stackpage=%08lx)\n",
151 	       current->comm, current->pid, (unsigned long)current);
152 	/*
153 	 * When in-kernel, we also print out the stack and code at the
154 	 * time of the fault..
155 	 */
156 	if (in_kernel) {
157 
158 		printk("\nStack: ");
159 		show_stack(NULL, (unsigned long *)esp);
160 
161 		printk("\nCode: ");
162 		if (regs->pc < PAGE_OFFSET)
163 			goto bad;
164 
165 		for (i = -24; i < 24; i++) {
166 			unsigned char c;
167 			if (__get_user(c, &((unsigned char *)regs->pc)[i])) {
168 bad:
169 				printk(" Bad PC value.");
170 				break;
171 			}
172 
173 			if (i == 0)
174 				printk("(%02x) ", c);
175 			else
176 				printk("%02x ", c);
177 		}
178 	}
179 	printk("\n");
180 }
181 
182 void nommu_dump_state(struct pt_regs *regs,
183 		      unsigned long ea, unsigned long vector)
184 {
185 	int i;
186 	unsigned long addr, stack = regs->sp;
187 
188 	printk("\n\r[nommu_dump_state] :: ea %lx, vector %lx\n\r", ea, vector);
189 
190 	printk("CPU #: %d\n"
191 	       "   PC: %08lx    SR: %08lx    SP: %08lx\n",
192 	       0, regs->pc, regs->sr, regs->sp);
193 	printk("GPR00: %08lx GPR01: %08lx GPR02: %08lx GPR03: %08lx\n",
194 	       0L, regs->gpr[1], regs->gpr[2], regs->gpr[3]);
195 	printk("GPR04: %08lx GPR05: %08lx GPR06: %08lx GPR07: %08lx\n",
196 	       regs->gpr[4], regs->gpr[5], regs->gpr[6], regs->gpr[7]);
197 	printk("GPR08: %08lx GPR09: %08lx GPR10: %08lx GPR11: %08lx\n",
198 	       regs->gpr[8], regs->gpr[9], regs->gpr[10], regs->gpr[11]);
199 	printk("GPR12: %08lx GPR13: %08lx GPR14: %08lx GPR15: %08lx\n",
200 	       regs->gpr[12], regs->gpr[13], regs->gpr[14], regs->gpr[15]);
201 	printk("GPR16: %08lx GPR17: %08lx GPR18: %08lx GPR19: %08lx\n",
202 	       regs->gpr[16], regs->gpr[17], regs->gpr[18], regs->gpr[19]);
203 	printk("GPR20: %08lx GPR21: %08lx GPR22: %08lx GPR23: %08lx\n",
204 	       regs->gpr[20], regs->gpr[21], regs->gpr[22], regs->gpr[23]);
205 	printk("GPR24: %08lx GPR25: %08lx GPR26: %08lx GPR27: %08lx\n",
206 	       regs->gpr[24], regs->gpr[25], regs->gpr[26], regs->gpr[27]);
207 	printk("GPR28: %08lx GPR29: %08lx GPR30: %08lx GPR31: %08lx\n",
208 	       regs->gpr[28], regs->gpr[29], regs->gpr[30], regs->gpr[31]);
209 	printk("  RES: %08lx oGPR11: %08lx syscallno: %08lx\n",
210 	       regs->gpr[11], regs->orig_gpr11, regs->syscallno);
211 
212 	printk("Process %s (pid: %d, stackpage=%08lx)\n",
213 	       ((struct task_struct *)(__pa(current)))->comm,
214 	       ((struct task_struct *)(__pa(current)))->pid,
215 	       (unsigned long)current);
216 
217 	printk("\nStack: ");
218 	printk("Stack dump [0x%08lx]:\n", (unsigned long)stack);
219 	for (i = 0; i < kstack_depth_to_print; i++) {
220 		if (((long)stack & (THREAD_SIZE - 1)) == 0)
221 			break;
222 		stack++;
223 
224 		printk("%lx :: sp + %02d: 0x%08lx\n", stack, i * 4,
225 		       *((unsigned long *)(__pa(stack))));
226 	}
227 	printk("\n");
228 
229 	printk("Call Trace:   ");
230 	i = 1;
231 	while (((long)stack & (THREAD_SIZE - 1)) != 0) {
232 		addr = *((unsigned long *)__pa(stack));
233 		stack++;
234 
235 		if (kernel_text_address(addr)) {
236 			if (i && ((i % 6) == 0))
237 				printk("\n ");
238 			printk(" [<%08lx>]", addr);
239 			i++;
240 		}
241 	}
242 	printk("\n");
243 
244 	printk("\nCode: ");
245 
246 	for (i = -24; i < 24; i++) {
247 		unsigned char c;
248 		c = ((unsigned char *)(__pa(regs->pc)))[i];
249 
250 		if (i == 0)
251 			printk("(%02x) ", c);
252 		else
253 			printk("%02x ", c);
254 	}
255 	printk("\n");
256 }
257 
258 /* This is normally the 'Oops' routine */
259 void die(const char *str, struct pt_regs *regs, long err)
260 {
261 
262 	console_verbose();
263 	printk("\n%s#: %04lx\n", str, err & 0xffff);
264 	show_registers(regs);
265 #ifdef CONFIG_JUMP_UPON_UNHANDLED_EXCEPTION
266 	printk("\n\nUNHANDLED_EXCEPTION: entering infinite loop\n");
267 
268 	/* shut down interrupts */
269 	local_irq_disable();
270 
271 	__asm__ __volatile__("l.nop   1");
272 	do {} while (1);
273 #endif
274 	do_exit(SIGSEGV);
275 }
276 
277 /* This is normally the 'Oops' routine */
278 void die_if_kernel(const char *str, struct pt_regs *regs, long err)
279 {
280 	if (user_mode(regs))
281 		return;
282 
283 	die(str, regs, err);
284 }
285 
286 void unhandled_exception(struct pt_regs *regs, int ea, int vector)
287 {
288 	printk("Unable to handle exception at EA =0x%x, vector 0x%x",
289 	       ea, vector);
290 	die("Oops", regs, 9);
291 }
292 
293 void __init trap_init(void)
294 {
295 	/* Nothing needs to be done */
296 }
297 
298 asmlinkage void do_trap(struct pt_regs *regs, unsigned long address)
299 {
300 	siginfo_t info;
301 	memset(&info, 0, sizeof(info));
302 	info.si_signo = SIGTRAP;
303 	info.si_code = TRAP_TRACE;
304 	info.si_addr = (void *)address;
305 	force_sig_info(SIGTRAP, &info, current);
306 
307 	regs->pc += 4;
308 }
309 
310 asmlinkage void do_unaligned_access(struct pt_regs *regs, unsigned long address)
311 {
312 	siginfo_t info;
313 
314 	if (user_mode(regs)) {
315 		/* Send a SIGSEGV */
316 		info.si_signo = SIGSEGV;
317 		info.si_errno = 0;
318 		/* info.si_code has been set above */
319 		info.si_addr = (void *)address;
320 		force_sig_info(SIGSEGV, &info, current);
321 	} else {
322 		printk("KERNEL: Unaligned Access 0x%.8lx\n", address);
323 		show_registers(regs);
324 		die("Die:", regs, address);
325 	}
326 
327 }
328 
329 asmlinkage void do_bus_fault(struct pt_regs *regs, unsigned long address)
330 {
331 	siginfo_t info;
332 
333 	if (user_mode(regs)) {
334 		/* Send a SIGBUS */
335 		info.si_signo = SIGBUS;
336 		info.si_errno = 0;
337 		info.si_code = BUS_ADRERR;
338 		info.si_addr = (void *)address;
339 		force_sig_info(SIGBUS, &info, current);
340 	} else {		/* Kernel mode */
341 		printk("KERNEL: Bus error (SIGBUS) 0x%.8lx\n", address);
342 		show_registers(regs);
343 		die("Die:", regs, address);
344 	}
345 }
346 
347 asmlinkage void do_illegal_instruction(struct pt_regs *regs,
348 				       unsigned long address)
349 {
350 	siginfo_t info;
351 
352 	if (user_mode(regs)) {
353 		/* Send a SIGILL */
354 		info.si_signo = SIGILL;
355 		info.si_errno = 0;
356 		info.si_code = ILL_ILLOPC;
357 		info.si_addr = (void *)address;
358 		force_sig_info(SIGBUS, &info, current);
359 	} else {		/* Kernel mode */
360 		printk("KERNEL: Illegal instruction (SIGILL) 0x%.8lx\n",
361 		       address);
362 		show_registers(regs);
363 		die("Die:", regs, address);
364 	}
365 }
366