xref: /openbmc/linux/arch/openrisc/kernel/traps.c (revision 94cdda6b)
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 void show_registers(struct pt_regs *regs)
109 {
110 	int i;
111 	int in_kernel = 1;
112 	unsigned long esp;
113 
114 	esp = (unsigned long)(&regs->sp);
115 	if (user_mode(regs))
116 		in_kernel = 0;
117 
118 	printk("CPU #: %d\n"
119 	       "   PC: %08lx    SR: %08lx    SP: %08lx\n",
120 	       smp_processor_id(), regs->pc, regs->sr, regs->sp);
121 	printk("GPR00: %08lx GPR01: %08lx GPR02: %08lx GPR03: %08lx\n",
122 	       0L, regs->gpr[1], regs->gpr[2], regs->gpr[3]);
123 	printk("GPR04: %08lx GPR05: %08lx GPR06: %08lx GPR07: %08lx\n",
124 	       regs->gpr[4], regs->gpr[5], regs->gpr[6], regs->gpr[7]);
125 	printk("GPR08: %08lx GPR09: %08lx GPR10: %08lx GPR11: %08lx\n",
126 	       regs->gpr[8], regs->gpr[9], regs->gpr[10], regs->gpr[11]);
127 	printk("GPR12: %08lx GPR13: %08lx GPR14: %08lx GPR15: %08lx\n",
128 	       regs->gpr[12], regs->gpr[13], regs->gpr[14], regs->gpr[15]);
129 	printk("GPR16: %08lx GPR17: %08lx GPR18: %08lx GPR19: %08lx\n",
130 	       regs->gpr[16], regs->gpr[17], regs->gpr[18], regs->gpr[19]);
131 	printk("GPR20: %08lx GPR21: %08lx GPR22: %08lx GPR23: %08lx\n",
132 	       regs->gpr[20], regs->gpr[21], regs->gpr[22], regs->gpr[23]);
133 	printk("GPR24: %08lx GPR25: %08lx GPR26: %08lx GPR27: %08lx\n",
134 	       regs->gpr[24], regs->gpr[25], regs->gpr[26], regs->gpr[27]);
135 	printk("GPR28: %08lx GPR29: %08lx GPR30: %08lx GPR31: %08lx\n",
136 	       regs->gpr[28], regs->gpr[29], regs->gpr[30], regs->gpr[31]);
137 	printk("  RES: %08lx oGPR11: %08lx\n",
138 	       regs->gpr[11], regs->orig_gpr11);
139 
140 	printk("Process %s (pid: %d, stackpage=%08lx)\n",
141 	       current->comm, current->pid, (unsigned long)current);
142 	/*
143 	 * When in-kernel, we also print out the stack and code at the
144 	 * time of the fault..
145 	 */
146 	if (in_kernel) {
147 
148 		printk("\nStack: ");
149 		show_stack(NULL, (unsigned long *)esp);
150 
151 		printk("\nCode: ");
152 		if (regs->pc < PAGE_OFFSET)
153 			goto bad;
154 
155 		for (i = -24; i < 24; i++) {
156 			unsigned char c;
157 			if (__get_user(c, &((unsigned char *)regs->pc)[i])) {
158 bad:
159 				printk(" Bad PC value.");
160 				break;
161 			}
162 
163 			if (i == 0)
164 				printk("(%02x) ", c);
165 			else
166 				printk("%02x ", c);
167 		}
168 	}
169 	printk("\n");
170 }
171 
172 void nommu_dump_state(struct pt_regs *regs,
173 		      unsigned long ea, unsigned long vector)
174 {
175 	int i;
176 	unsigned long addr, stack = regs->sp;
177 
178 	printk("\n\r[nommu_dump_state] :: ea %lx, vector %lx\n\r", ea, vector);
179 
180 	printk("CPU #: %d\n"
181 	       "   PC: %08lx    SR: %08lx    SP: %08lx\n",
182 	       0, regs->pc, regs->sr, regs->sp);
183 	printk("GPR00: %08lx GPR01: %08lx GPR02: %08lx GPR03: %08lx\n",
184 	       0L, regs->gpr[1], regs->gpr[2], regs->gpr[3]);
185 	printk("GPR04: %08lx GPR05: %08lx GPR06: %08lx GPR07: %08lx\n",
186 	       regs->gpr[4], regs->gpr[5], regs->gpr[6], regs->gpr[7]);
187 	printk("GPR08: %08lx GPR09: %08lx GPR10: %08lx GPR11: %08lx\n",
188 	       regs->gpr[8], regs->gpr[9], regs->gpr[10], regs->gpr[11]);
189 	printk("GPR12: %08lx GPR13: %08lx GPR14: %08lx GPR15: %08lx\n",
190 	       regs->gpr[12], regs->gpr[13], regs->gpr[14], regs->gpr[15]);
191 	printk("GPR16: %08lx GPR17: %08lx GPR18: %08lx GPR19: %08lx\n",
192 	       regs->gpr[16], regs->gpr[17], regs->gpr[18], regs->gpr[19]);
193 	printk("GPR20: %08lx GPR21: %08lx GPR22: %08lx GPR23: %08lx\n",
194 	       regs->gpr[20], regs->gpr[21], regs->gpr[22], regs->gpr[23]);
195 	printk("GPR24: %08lx GPR25: %08lx GPR26: %08lx GPR27: %08lx\n",
196 	       regs->gpr[24], regs->gpr[25], regs->gpr[26], regs->gpr[27]);
197 	printk("GPR28: %08lx GPR29: %08lx GPR30: %08lx GPR31: %08lx\n",
198 	       regs->gpr[28], regs->gpr[29], regs->gpr[30], regs->gpr[31]);
199 	printk("  RES: %08lx oGPR11: %08lx\n",
200 	       regs->gpr[11], regs->orig_gpr11);
201 
202 	printk("Process %s (pid: %d, stackpage=%08lx)\n",
203 	       ((struct task_struct *)(__pa(current)))->comm,
204 	       ((struct task_struct *)(__pa(current)))->pid,
205 	       (unsigned long)current);
206 
207 	printk("\nStack: ");
208 	printk("Stack dump [0x%08lx]:\n", (unsigned long)stack);
209 	for (i = 0; i < kstack_depth_to_print; i++) {
210 		if (((long)stack & (THREAD_SIZE - 1)) == 0)
211 			break;
212 		stack++;
213 
214 		printk("%lx :: sp + %02d: 0x%08lx\n", stack, i * 4,
215 		       *((unsigned long *)(__pa(stack))));
216 	}
217 	printk("\n");
218 
219 	printk("Call Trace:   ");
220 	i = 1;
221 	while (((long)stack & (THREAD_SIZE - 1)) != 0) {
222 		addr = *((unsigned long *)__pa(stack));
223 		stack++;
224 
225 		if (kernel_text_address(addr)) {
226 			if (i && ((i % 6) == 0))
227 				printk("\n ");
228 			printk(" [<%08lx>]", addr);
229 			i++;
230 		}
231 	}
232 	printk("\n");
233 
234 	printk("\nCode: ");
235 
236 	for (i = -24; i < 24; i++) {
237 		unsigned char c;
238 		c = ((unsigned char *)(__pa(regs->pc)))[i];
239 
240 		if (i == 0)
241 			printk("(%02x) ", c);
242 		else
243 			printk("%02x ", c);
244 	}
245 	printk("\n");
246 }
247 
248 /* This is normally the 'Oops' routine */
249 void die(const char *str, struct pt_regs *regs, long err)
250 {
251 
252 	console_verbose();
253 	printk("\n%s#: %04lx\n", str, err & 0xffff);
254 	show_registers(regs);
255 #ifdef CONFIG_JUMP_UPON_UNHANDLED_EXCEPTION
256 	printk("\n\nUNHANDLED_EXCEPTION: entering infinite loop\n");
257 
258 	/* shut down interrupts */
259 	local_irq_disable();
260 
261 	__asm__ __volatile__("l.nop   1");
262 	do {} while (1);
263 #endif
264 	do_exit(SIGSEGV);
265 }
266 
267 /* This is normally the 'Oops' routine */
268 void die_if_kernel(const char *str, struct pt_regs *regs, long err)
269 {
270 	if (user_mode(regs))
271 		return;
272 
273 	die(str, regs, err);
274 }
275 
276 void unhandled_exception(struct pt_regs *regs, int ea, int vector)
277 {
278 	printk("Unable to handle exception at EA =0x%x, vector 0x%x",
279 	       ea, vector);
280 	die("Oops", regs, 9);
281 }
282 
283 void __init trap_init(void)
284 {
285 	/* Nothing needs to be done */
286 }
287 
288 asmlinkage void do_trap(struct pt_regs *regs, unsigned long address)
289 {
290 	siginfo_t info;
291 	memset(&info, 0, sizeof(info));
292 	info.si_signo = SIGTRAP;
293 	info.si_code = TRAP_TRACE;
294 	info.si_addr = (void *)address;
295 	force_sig_info(SIGTRAP, &info, current);
296 
297 	regs->pc += 4;
298 }
299 
300 asmlinkage void do_unaligned_access(struct pt_regs *regs, unsigned long address)
301 {
302 	siginfo_t info;
303 
304 	if (user_mode(regs)) {
305 		/* Send a SIGSEGV */
306 		info.si_signo = SIGSEGV;
307 		info.si_errno = 0;
308 		/* info.si_code has been set above */
309 		info.si_addr = (void *)address;
310 		force_sig_info(SIGSEGV, &info, current);
311 	} else {
312 		printk("KERNEL: Unaligned Access 0x%.8lx\n", address);
313 		show_registers(regs);
314 		die("Die:", regs, address);
315 	}
316 
317 }
318 
319 asmlinkage void do_bus_fault(struct pt_regs *regs, unsigned long address)
320 {
321 	siginfo_t info;
322 
323 	if (user_mode(regs)) {
324 		/* Send a SIGBUS */
325 		info.si_signo = SIGBUS;
326 		info.si_errno = 0;
327 		info.si_code = BUS_ADRERR;
328 		info.si_addr = (void *)address;
329 		force_sig_info(SIGBUS, &info, current);
330 	} else {		/* Kernel mode */
331 		printk("KERNEL: Bus error (SIGBUS) 0x%.8lx\n", address);
332 		show_registers(regs);
333 		die("Die:", regs, address);
334 	}
335 }
336 
337 asmlinkage void do_illegal_instruction(struct pt_regs *regs,
338 				       unsigned long address)
339 {
340 	siginfo_t info;
341 
342 	if (user_mode(regs)) {
343 		/* Send a SIGILL */
344 		info.si_signo = SIGILL;
345 		info.si_errno = 0;
346 		info.si_code = ILL_ILLOPC;
347 		info.si_addr = (void *)address;
348 		force_sig_info(SIGBUS, &info, current);
349 	} else {		/* Kernel mode */
350 		printk("KERNEL: Illegal instruction (SIGILL) 0x%.8lx\n",
351 		       address);
352 		show_registers(regs);
353 		die("Die:", regs, address);
354 	}
355 }
356