blob: 866c7c7a8236ef05788a9b87dcaae172b07e3738 [file] [log] [blame]
Paul Mundt6b002232006-10-12 17:07:45 +09001/*
2 * 'traps.c' handles hardware traps and faults after we have saved some
3 * state in 'entry.S'.
Linus Torvalds1da177e2005-04-16 15:20:36 -07004 *
5 * SuperH version: Copyright (C) 1999 Niibe Yutaka
6 * Copyright (C) 2000 Philipp Rumpf
7 * Copyright (C) 2000 David Howells
Paul Mundt3a2e1172007-05-01 16:33:10 +09008 * Copyright (C) 2002 - 2007 Paul Mundt
Paul Mundt6b002232006-10-12 17:07:45 +09009 *
10 * This file is subject to the terms and conditions of the GNU General Public
11 * License. See the file "COPYING" in the main directory of this archive
12 * for more details.
Linus Torvalds1da177e2005-04-16 15:20:36 -070013 */
Linus Torvalds1da177e2005-04-16 15:20:36 -070014#include <linux/kernel.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070015#include <linux/ptrace.h>
Russell Kingba84be22009-01-06 14:41:07 -080016#include <linux/hardirq.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070017#include <linux/init.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070018#include <linux/spinlock.h>
19#include <linux/module.h>
20#include <linux/kallsyms.h>
Paul Mundt1f666582006-10-19 16:20:25 +090021#include <linux/io.h>
Paul Mundtfa691512007-03-08 19:41:21 +090022#include <linux/bug.h>
Paul Mundt9b8c90e2006-12-06 11:07:51 +090023#include <linux/debug_locks.h>
Paul Mundtb118ca52007-05-09 10:55:38 +090024#include <linux/kdebug.h>
Paul Mundte1132762007-05-15 08:36:36 +090025#include <linux/kexec.h>
Paul Mundtdc34d312006-12-08 17:41:43 +090026#include <linux/limits.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070027#include <asm/system.h>
28#include <asm/uaccess.h>
Andrew Mortonfad0f902008-04-16 02:03:51 +090029#include <asm/fpu.h>
Chris Smithd39f5452008-09-05 17:15:39 +090030#include <asm/kprobes.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070031
Linus Torvalds1da177e2005-04-16 15:20:36 -070032#ifdef CONFIG_CPU_SH2
Yoshinori Sato0983b312006-11-05 15:58:47 +090033# define TRAP_RESERVED_INST 4
34# define TRAP_ILLEGAL_SLOT_INST 6
35# define TRAP_ADDRESS_ERROR 9
36# ifdef CONFIG_CPU_SH2A
Peter Griffincd894362009-05-08 15:51:51 +010037# define TRAP_UBC 12
Yoshinori Sato6e80f5e2008-07-10 01:20:03 +090038# define TRAP_FPU_ERROR 13
Yoshinori Sato0983b312006-11-05 15:58:47 +090039# define TRAP_DIVZERO_ERROR 17
40# define TRAP_DIVOVF_ERROR 18
41# endif
Linus Torvalds1da177e2005-04-16 15:20:36 -070042#else
43#define TRAP_RESERVED_INST 12
44#define TRAP_ILLEGAL_SLOT_INST 13
45#endif
46
Paul Mundt6b002232006-10-12 17:07:45 +090047static void dump_mem(const char *str, unsigned long bottom, unsigned long top)
48{
49 unsigned long p;
50 int i;
51
52 printk("%s(0x%08lx to 0x%08lx)\n", str, bottom, top);
53
54 for (p = bottom & ~31; p < top; ) {
55 printk("%04lx: ", p & 0xffff);
56
57 for (i = 0; i < 8; i++, p += 4) {
58 unsigned int val;
59
60 if (p < bottom || p >= top)
61 printk(" ");
62 else {
63 if (__get_user(val, (unsigned int __user *)p)) {
64 printk("\n");
65 return;
66 }
67 printk("%08x ", val);
68 }
69 }
70 printk("\n");
71 }
72}
Linus Torvalds1da177e2005-04-16 15:20:36 -070073
Paul Mundt3a2e1172007-05-01 16:33:10 +090074static DEFINE_SPINLOCK(die_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -070075
76void die(const char * str, struct pt_regs * regs, long err)
77{
78 static int die_counter;
79
Paul Mundt55273982007-06-18 18:57:13 +090080 oops_enter();
81
Linus Torvalds1da177e2005-04-16 15:20:36 -070082 console_verbose();
83 spin_lock_irq(&die_lock);
Paul Mundt6b002232006-10-12 17:07:45 +090084 bust_spinlocks(1);
85
Linus Torvalds1da177e2005-04-16 15:20:36 -070086 printk("%s: %04lx [#%d]\n", str, err & 0xffff, ++die_counter);
Paul Mundt6b002232006-10-12 17:07:45 +090087
Paul Mundt6b002232006-10-12 17:07:45 +090088 print_modules();
Linus Torvalds1da177e2005-04-16 15:20:36 -070089 show_regs(regs);
Paul Mundt6b002232006-10-12 17:07:45 +090090
Alexey Dobriyan19c58702007-10-18 23:40:41 -070091 printk("Process: %s (pid: %d, stack limit = %p)\n", current->comm,
92 task_pid_nr(current), task_stack_page(current) + 1);
Paul Mundt6b002232006-10-12 17:07:45 +090093
94 if (!user_mode(regs) || in_interrupt())
95 dump_mem("Stack: ", regs->regs[15], THREAD_SIZE +
Stuart Menefyb5a1bcb2006-11-21 13:34:04 +090096 (unsigned long)task_stack_page(current));
Paul Mundt6b002232006-10-12 17:07:45 +090097
Paul Mundtc9306f02008-10-21 18:33:36 +090098 notify_die(DIE_OOPS, str, regs, err, 255, SIGSEGV);
99
Paul Mundt6b002232006-10-12 17:07:45 +0900100 bust_spinlocks(0);
Pavel Emelianovbcdcd8e2007-07-17 04:03:42 -0700101 add_taint(TAINT_DIE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700102 spin_unlock_irq(&die_lock);
Paul Mundte1132762007-05-15 08:36:36 +0900103
104 if (kexec_should_crash(current))
105 crash_kexec(regs);
106
107 if (in_interrupt())
108 panic("Fatal exception in interrupt");
109
110 if (panic_on_oops)
111 panic("Fatal exception");
112
Paul Mundt55273982007-06-18 18:57:13 +0900113 oops_exit();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700114 do_exit(SIGSEGV);
115}
116
Paul Mundt6b002232006-10-12 17:07:45 +0900117static inline void die_if_kernel(const char *str, struct pt_regs *regs,
118 long err)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700119{
120 if (!user_mode(regs))
121 die(str, regs, err);
122}
123
Linus Torvalds1da177e2005-04-16 15:20:36 -0700124/*
125 * try and fix up kernelspace address errors
126 * - userspace errors just cause EFAULT to be returned, resulting in SEGV
127 * - kernel/userspace interfaces cause a jump to an appropriate handler
128 * - other kernel errors are bad
Linus Torvalds1da177e2005-04-16 15:20:36 -0700129 */
SUGIOKA Toshinobu2afb4472009-01-21 09:42:10 +0900130static void die_if_no_fixup(const char * str, struct pt_regs * regs, long err)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700131{
Paul Mundt6b002232006-10-12 17:07:45 +0900132 if (!user_mode(regs)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700133 const struct exception_table_entry *fixup;
134 fixup = search_exception_tables(regs->pc);
135 if (fixup) {
136 regs->pc = fixup->fixup;
SUGIOKA Toshinobu2afb4472009-01-21 09:42:10 +0900137 return;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700138 }
Matt Flemingb344e242009-08-16 21:54:48 +0100139
Linus Torvalds1da177e2005-04-16 15:20:36 -0700140 die(str, regs, err);
141 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700142}
143
Magnus Damm86c01792008-02-07 00:02:50 +0900144static inline void sign_extend(unsigned int count, unsigned char *dst)
145{
146#ifdef __LITTLE_ENDIAN__
Magnus Damm4252c652008-02-07 19:58:46 +0900147 if ((count == 1) && dst[0] & 0x80) {
148 dst[1] = 0xff;
149 dst[2] = 0xff;
150 dst[3] = 0xff;
151 }
Magnus Damm86c01792008-02-07 00:02:50 +0900152 if ((count == 2) && dst[1] & 0x80) {
153 dst[2] = 0xff;
154 dst[3] = 0xff;
155 }
156#else
Magnus Damm4252c652008-02-07 19:58:46 +0900157 if ((count == 1) && dst[3] & 0x80) {
158 dst[2] = 0xff;
Magnus Damm86c01792008-02-07 00:02:50 +0900159 dst[1] = 0xff;
Magnus Damm4252c652008-02-07 19:58:46 +0900160 dst[0] = 0xff;
161 }
162 if ((count == 2) && dst[2] & 0x80) {
163 dst[1] = 0xff;
164 dst[0] = 0xff;
Magnus Damm86c01792008-02-07 00:02:50 +0900165 }
166#endif
167}
168
Magnus Damme7cc9a72008-02-07 20:18:21 +0900169static struct mem_access user_mem_access = {
170 copy_from_user,
171 copy_to_user,
172};
173
Linus Torvalds1da177e2005-04-16 15:20:36 -0700174/*
175 * handle an instruction that does an unaligned memory access by emulating the
176 * desired behaviour
177 * - note that PC _may not_ point to the faulting instruction
178 * (if that instruction is in a branch delay slot)
179 * - return 0 if emulation okay, -EFAULT on existential error
180 */
Paul Mundt2bcfffa2009-05-09 16:02:08 +0900181static int handle_unaligned_ins(insn_size_t instruction, struct pt_regs *regs,
Magnus Damme7cc9a72008-02-07 20:18:21 +0900182 struct mem_access *ma)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700183{
184 int ret, index, count;
185 unsigned long *rm, *rn;
186 unsigned char *src, *dst;
Paul Mundtfa439722008-09-04 18:53:58 +0900187 unsigned char __user *srcu, *dstu;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700188
189 index = (instruction>>8)&15; /* 0x0F00 */
190 rn = &regs->regs[index];
191
192 index = (instruction>>4)&15; /* 0x00F0 */
193 rm = &regs->regs[index];
194
195 count = 1<<(instruction&3);
196
197 ret = -EFAULT;
198 switch (instruction>>12) {
199 case 0: /* mov.[bwl] to/from memory via r0+rn */
200 if (instruction & 8) {
201 /* from memory */
Paul Mundtfa439722008-09-04 18:53:58 +0900202 srcu = (unsigned char __user *)*rm;
203 srcu += regs->regs[0];
204 dst = (unsigned char *)rn;
205 *(unsigned long *)dst = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700206
Magnus Damm86c01792008-02-07 00:02:50 +0900207#if !defined(__LITTLE_ENDIAN__)
208 dst += 4-count;
209#endif
Paul Mundtfa439722008-09-04 18:53:58 +0900210 if (ma->from(dst, srcu, count))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700211 goto fetch_fault;
212
Magnus Damm86c01792008-02-07 00:02:50 +0900213 sign_extend(count, dst);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700214 } else {
215 /* to memory */
Paul Mundtfa439722008-09-04 18:53:58 +0900216 src = (unsigned char *)rm;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700217#if !defined(__LITTLE_ENDIAN__)
218 src += 4-count;
219#endif
Paul Mundtfa439722008-09-04 18:53:58 +0900220 dstu = (unsigned char __user *)*rn;
221 dstu += regs->regs[0];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700222
Paul Mundtfa439722008-09-04 18:53:58 +0900223 if (ma->to(dstu, src, count))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700224 goto fetch_fault;
225 }
226 ret = 0;
227 break;
228
229 case 1: /* mov.l Rm,@(disp,Rn) */
230 src = (unsigned char*) rm;
Paul Mundtfa439722008-09-04 18:53:58 +0900231 dstu = (unsigned char __user *)*rn;
232 dstu += (instruction&0x000F)<<2;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700233
Paul Mundtfa439722008-09-04 18:53:58 +0900234 if (ma->to(dstu, src, 4))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700235 goto fetch_fault;
236 ret = 0;
Stuart Menefyb5a1bcb2006-11-21 13:34:04 +0900237 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700238
239 case 2: /* mov.[bwl] to memory, possibly with pre-decrement */
240 if (instruction & 4)
241 *rn -= count;
242 src = (unsigned char*) rm;
Paul Mundtfa439722008-09-04 18:53:58 +0900243 dstu = (unsigned char __user *)*rn;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700244#if !defined(__LITTLE_ENDIAN__)
245 src += 4-count;
246#endif
Paul Mundtfa439722008-09-04 18:53:58 +0900247 if (ma->to(dstu, src, count))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700248 goto fetch_fault;
249 ret = 0;
250 break;
251
252 case 5: /* mov.l @(disp,Rm),Rn */
Paul Mundtfa439722008-09-04 18:53:58 +0900253 srcu = (unsigned char __user *)*rm;
254 srcu += (instruction & 0x000F) << 2;
255 dst = (unsigned char *)rn;
256 *(unsigned long *)dst = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700257
Paul Mundtfa439722008-09-04 18:53:58 +0900258 if (ma->from(dst, srcu, 4))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700259 goto fetch_fault;
260 ret = 0;
Stuart Menefyb5a1bcb2006-11-21 13:34:04 +0900261 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700262
263 case 6: /* mov.[bwl] from memory, possibly with post-increment */
Paul Mundtfa439722008-09-04 18:53:58 +0900264 srcu = (unsigned char __user *)*rm;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700265 if (instruction & 4)
266 *rm += count;
267 dst = (unsigned char*) rn;
268 *(unsigned long*)dst = 0;
Stuart Menefyb5a1bcb2006-11-21 13:34:04 +0900269
Magnus Damm86c01792008-02-07 00:02:50 +0900270#if !defined(__LITTLE_ENDIAN__)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700271 dst += 4-count;
Magnus Damm86c01792008-02-07 00:02:50 +0900272#endif
Paul Mundtfa439722008-09-04 18:53:58 +0900273 if (ma->from(dst, srcu, count))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700274 goto fetch_fault;
Magnus Damm86c01792008-02-07 00:02:50 +0900275 sign_extend(count, dst);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700276 ret = 0;
277 break;
278
279 case 8:
280 switch ((instruction&0xFF00)>>8) {
281 case 0x81: /* mov.w R0,@(disp,Rn) */
Paul Mundtfa439722008-09-04 18:53:58 +0900282 src = (unsigned char *) &regs->regs[0];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700283#if !defined(__LITTLE_ENDIAN__)
284 src += 2;
285#endif
Paul Mundtfa439722008-09-04 18:53:58 +0900286 dstu = (unsigned char __user *)*rm; /* called Rn in the spec */
287 dstu += (instruction & 0x000F) << 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700288
Paul Mundtfa439722008-09-04 18:53:58 +0900289 if (ma->to(dstu, src, 2))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700290 goto fetch_fault;
291 ret = 0;
292 break;
293
294 case 0x85: /* mov.w @(disp,Rm),R0 */
Paul Mundtfa439722008-09-04 18:53:58 +0900295 srcu = (unsigned char __user *)*rm;
296 srcu += (instruction & 0x000F) << 1;
297 dst = (unsigned char *) &regs->regs[0];
298 *(unsigned long *)dst = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700299
300#if !defined(__LITTLE_ENDIAN__)
301 dst += 2;
302#endif
Paul Mundtfa439722008-09-04 18:53:58 +0900303 if (ma->from(dst, srcu, 2))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700304 goto fetch_fault;
Magnus Damm86c01792008-02-07 00:02:50 +0900305 sign_extend(2, dst);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700306 ret = 0;
307 break;
308 }
309 break;
310 }
311 return ret;
312
313 fetch_fault:
314 /* Argh. Address not only misaligned but also non-existent.
315 * Raise an EFAULT and see if it's trapped
316 */
SUGIOKA Toshinobu2afb4472009-01-21 09:42:10 +0900317 die_if_no_fixup("Fault in unaligned fixup", regs, 0);
318 return -EFAULT;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700319}
320
321/*
322 * emulate the instruction in the delay slot
323 * - fetches the instruction from PC+2
324 */
Magnus Damme7cc9a72008-02-07 20:18:21 +0900325static inline int handle_delayslot(struct pt_regs *regs,
Paul Mundt2bcfffa2009-05-09 16:02:08 +0900326 insn_size_t old_instruction,
Magnus Damme7cc9a72008-02-07 20:18:21 +0900327 struct mem_access *ma)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700328{
Paul Mundt2bcfffa2009-05-09 16:02:08 +0900329 insn_size_t instruction;
Paul Mundtfa439722008-09-04 18:53:58 +0900330 void __user *addr = (void __user *)(regs->pc +
331 instruction_size(old_instruction));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700332
Magnus Damm4b5a9ef2008-02-07 20:04:12 +0900333 if (copy_from_user(&instruction, addr, sizeof(instruction))) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700334 /* the instruction-fetch faulted */
335 if (user_mode(regs))
336 return -EFAULT;
337
338 /* kernel */
Stuart Menefyb5a1bcb2006-11-21 13:34:04 +0900339 die("delay-slot-insn faulting in handle_unaligned_delayslot",
340 regs, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700341 }
342
Magnus Damme7cc9a72008-02-07 20:18:21 +0900343 return handle_unaligned_ins(instruction, regs, ma);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700344}
345
346/*
347 * handle an instruction that does an unaligned memory access
348 * - have to be careful of branch delay-slot instructions that fault
349 * SH3:
350 * - if the branch would be taken PC points to the branch
351 * - if the branch would not be taken, PC points to delay-slot
352 * SH4:
353 * - PC always points to delayed branch
354 * - return 0 if handled, -EFAULT if failed (may not return if in kernel)
355 */
356
357/* Macros to determine offset from current PC for branch instructions */
358/* Explicit type coercion is used to force sign extension where needed */
359#define SH_PC_8BIT_OFFSET(instr) ((((signed char)(instr))*2) + 4)
360#define SH_PC_12BIT_OFFSET(instr) ((((signed short)(instr<<4))>>3) + 4)
361
Paul Mundt2bcfffa2009-05-09 16:02:08 +0900362int handle_unaligned_access(insn_size_t instruction, struct pt_regs *regs,
Magnus Damme7cc9a72008-02-07 20:18:21 +0900363 struct mem_access *ma)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700364{
365 u_int rm;
366 int ret, index;
367
368 index = (instruction>>8)&15; /* 0x0F00 */
369 rm = regs->regs[index];
370
Andre Draszik9a4af022009-08-24 14:38:27 +0900371 /* shout about fixups */
372 if (printk_ratelimit())
373 printk(KERN_NOTICE "Fixing up unaligned %s access "
Stuart Menefyb5a1bcb2006-11-21 13:34:04 +0900374 "in \"%s\" pid=%d pc=0x%p ins=0x%04hx\n",
Andre Draszik9a4af022009-08-24 14:38:27 +0900375 user_mode(regs) ? "userspace" : "kernel",
Alexey Dobriyan19c58702007-10-18 23:40:41 -0700376 current->comm, task_pid_nr(current),
Magnus Damm4b5a9ef2008-02-07 20:04:12 +0900377 (void *)regs->pc, instruction);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700378
379 ret = -EFAULT;
380 switch (instruction&0xF000) {
381 case 0x0000:
382 if (instruction==0x000B) {
383 /* rts */
Magnus Damme7cc9a72008-02-07 20:18:21 +0900384 ret = handle_delayslot(regs, instruction, ma);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700385 if (ret==0)
386 regs->pc = regs->pr;
387 }
388 else if ((instruction&0x00FF)==0x0023) {
389 /* braf @Rm */
Magnus Damme7cc9a72008-02-07 20:18:21 +0900390 ret = handle_delayslot(regs, instruction, ma);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700391 if (ret==0)
392 regs->pc += rm + 4;
393 }
394 else if ((instruction&0x00FF)==0x0003) {
395 /* bsrf @Rm */
Magnus Damme7cc9a72008-02-07 20:18:21 +0900396 ret = handle_delayslot(regs, instruction, ma);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700397 if (ret==0) {
398 regs->pr = regs->pc + 4;
399 regs->pc += rm + 4;
400 }
401 }
402 else {
403 /* mov.[bwl] to/from memory via r0+rn */
404 goto simple;
405 }
406 break;
407
408 case 0x1000: /* mov.l Rm,@(disp,Rn) */
409 goto simple;
410
411 case 0x2000: /* mov.[bwl] to memory, possibly with pre-decrement */
412 goto simple;
413
414 case 0x4000:
415 if ((instruction&0x00FF)==0x002B) {
416 /* jmp @Rm */
Magnus Damme7cc9a72008-02-07 20:18:21 +0900417 ret = handle_delayslot(regs, instruction, ma);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700418 if (ret==0)
419 regs->pc = rm;
420 }
421 else if ((instruction&0x00FF)==0x000B) {
422 /* jsr @Rm */
Magnus Damme7cc9a72008-02-07 20:18:21 +0900423 ret = handle_delayslot(regs, instruction, ma);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700424 if (ret==0) {
425 regs->pr = regs->pc + 4;
426 regs->pc = rm;
427 }
428 }
429 else {
430 /* mov.[bwl] to/from memory via r0+rn */
431 goto simple;
432 }
433 break;
434
435 case 0x5000: /* mov.l @(disp,Rm),Rn */
436 goto simple;
437
438 case 0x6000: /* mov.[bwl] from memory, possibly with post-increment */
439 goto simple;
440
441 case 0x8000: /* bf lab, bf/s lab, bt lab, bt/s lab */
442 switch (instruction&0x0F00) {
443 case 0x0100: /* mov.w R0,@(disp,Rm) */
444 goto simple;
445 case 0x0500: /* mov.w @(disp,Rm),R0 */
446 goto simple;
447 case 0x0B00: /* bf lab - no delayslot*/
448 break;
449 case 0x0F00: /* bf/s lab */
Magnus Damme7cc9a72008-02-07 20:18:21 +0900450 ret = handle_delayslot(regs, instruction, ma);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700451 if (ret==0) {
452#if defined(CONFIG_CPU_SH4) || defined(CONFIG_SH7705_CACHE_32KB)
453 if ((regs->sr & 0x00000001) != 0)
454 regs->pc += 4; /* next after slot */
455 else
456#endif
457 regs->pc += SH_PC_8BIT_OFFSET(instruction);
458 }
459 break;
460 case 0x0900: /* bt lab - no delayslot */
461 break;
462 case 0x0D00: /* bt/s lab */
Magnus Damme7cc9a72008-02-07 20:18:21 +0900463 ret = handle_delayslot(regs, instruction, ma);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700464 if (ret==0) {
465#if defined(CONFIG_CPU_SH4) || defined(CONFIG_SH7705_CACHE_32KB)
466 if ((regs->sr & 0x00000001) == 0)
467 regs->pc += 4; /* next after slot */
468 else
469#endif
470 regs->pc += SH_PC_8BIT_OFFSET(instruction);
471 }
472 break;
473 }
474 break;
475
476 case 0xA000: /* bra label */
Magnus Damme7cc9a72008-02-07 20:18:21 +0900477 ret = handle_delayslot(regs, instruction, ma);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700478 if (ret==0)
479 regs->pc += SH_PC_12BIT_OFFSET(instruction);
480 break;
481
482 case 0xB000: /* bsr label */
Magnus Damme7cc9a72008-02-07 20:18:21 +0900483 ret = handle_delayslot(regs, instruction, ma);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700484 if (ret==0) {
485 regs->pr = regs->pc + 4;
486 regs->pc += SH_PC_12BIT_OFFSET(instruction);
487 }
488 break;
489 }
490 return ret;
491
492 /* handle non-delay-slot instruction */
493 simple:
Magnus Damme7cc9a72008-02-07 20:18:21 +0900494 ret = handle_unaligned_ins(instruction, regs, ma);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700495 if (ret==0)
Paul Mundt53f983a2007-05-08 15:31:48 +0900496 regs->pc += instruction_size(instruction);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700497 return ret;
498}
499
500/*
Stuart Menefyb5a1bcb2006-11-21 13:34:04 +0900501 * Handle various address error exceptions:
502 * - instruction address error:
503 * misaligned PC
504 * PC >= 0x80000000 in user mode
505 * - data address error (read and write)
506 * misaligned data access
507 * access to >= 0x80000000 is user mode
508 * Unfortuntaly we can't distinguish between instruction address error
Simon Arlotte868d612007-05-14 08:15:10 +0900509 * and data address errors caused by read accesses.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700510 */
Stuart Menefyf0bc8142006-11-21 11:16:57 +0900511asmlinkage void do_address_error(struct pt_regs *regs,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700512 unsigned long writeaccess,
513 unsigned long address)
514{
Yoshinori Sato0983b312006-11-05 15:58:47 +0900515 unsigned long error_code = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700516 mm_segment_t oldfs;
Stuart Menefyb5a1bcb2006-11-21 13:34:04 +0900517 siginfo_t info;
Paul Mundt2bcfffa2009-05-09 16:02:08 +0900518 insn_size_t instruction;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700519 int tmp;
520
Yoshinori Sato0983b312006-11-05 15:58:47 +0900521 /* Intentional ifdef */
522#ifdef CONFIG_CPU_HAS_SR_RB
Paul Mundt4c59e292008-09-21 12:00:23 +0900523 error_code = lookup_exception_vector();
Yoshinori Sato0983b312006-11-05 15:58:47 +0900524#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700525
526 oldfs = get_fs();
527
528 if (user_mode(regs)) {
Stuart Menefyb5a1bcb2006-11-21 13:34:04 +0900529 int si_code = BUS_ADRERR;
530
Linus Torvalds1da177e2005-04-16 15:20:36 -0700531 local_irq_enable();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700532
533 /* bad PC is not something we can fix */
Stuart Menefyb5a1bcb2006-11-21 13:34:04 +0900534 if (regs->pc & 1) {
535 si_code = BUS_ADRALN;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700536 goto uspace_segv;
Stuart Menefyb5a1bcb2006-11-21 13:34:04 +0900537 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700538
539 set_fs(USER_DS);
Paul Mundtfa439722008-09-04 18:53:58 +0900540 if (copy_from_user(&instruction, (void __user *)(regs->pc),
Magnus Damm4b5a9ef2008-02-07 20:04:12 +0900541 sizeof(instruction))) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700542 /* Argh. Fault on the instruction itself.
543 This should never happen non-SMP
544 */
545 set_fs(oldfs);
546 goto uspace_segv;
547 }
548
Magnus Damme7cc9a72008-02-07 20:18:21 +0900549 tmp = handle_unaligned_access(instruction, regs,
550 &user_mem_access);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700551 set_fs(oldfs);
552
553 if (tmp==0)
554 return; /* sorted */
Stuart Menefyb5a1bcb2006-11-21 13:34:04 +0900555uspace_segv:
556 printk(KERN_NOTICE "Sending SIGBUS to \"%s\" due to unaligned "
557 "access (PC %lx PR %lx)\n", current->comm, regs->pc,
558 regs->pr);
559
560 info.si_signo = SIGBUS;
561 info.si_errno = 0;
562 info.si_code = si_code;
Paul Mundte08f4572007-05-14 12:52:56 +0900563 info.si_addr = (void __user *)address;
Stuart Menefyb5a1bcb2006-11-21 13:34:04 +0900564 force_sig_info(SIGBUS, &info, current);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700565 } else {
566 if (regs->pc & 1)
567 die("unaligned program counter", regs, error_code);
568
569 set_fs(KERNEL_DS);
Paul Mundtfa439722008-09-04 18:53:58 +0900570 if (copy_from_user(&instruction, (void __user *)(regs->pc),
Magnus Damm4b5a9ef2008-02-07 20:04:12 +0900571 sizeof(instruction))) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700572 /* Argh. Fault on the instruction itself.
573 This should never happen non-SMP
574 */
575 set_fs(oldfs);
576 die("insn faulting in do_address_error", regs, 0);
577 }
578
Magnus Damme7cc9a72008-02-07 20:18:21 +0900579 handle_unaligned_access(instruction, regs, &user_mem_access);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700580 set_fs(oldfs);
581 }
582}
583
584#ifdef CONFIG_SH_DSP
585/*
586 * SH-DSP support gerg@snapgear.com.
587 */
588int is_dsp_inst(struct pt_regs *regs)
589{
Paul Mundt882c12c2007-05-14 17:26:34 +0900590 unsigned short inst = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700591
Stuart Menefyf0bc8142006-11-21 11:16:57 +0900592 /*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700593 * Safe guard if DSP mode is already enabled or we're lacking
594 * the DSP altogether.
595 */
Paul Mundt11c19652006-12-25 10:19:56 +0900596 if (!(current_cpu_data.flags & CPU_HAS_DSP) || (regs->sr & SR_DSP))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700597 return 0;
598
599 get_user(inst, ((unsigned short *) regs->pc));
600
601 inst &= 0xf000;
602
603 /* Check for any type of DSP or support instruction */
604 if ((inst == 0xf000) || (inst == 0x4000))
605 return 1;
606
607 return 0;
608}
609#else
610#define is_dsp_inst(regs) (0)
611#endif /* CONFIG_SH_DSP */
612
Yoshinori Sato0983b312006-11-05 15:58:47 +0900613#ifdef CONFIG_CPU_SH2A
614asmlinkage void do_divide_error(unsigned long r4, unsigned long r5,
615 unsigned long r6, unsigned long r7,
Stuart Menefyf0bc8142006-11-21 11:16:57 +0900616 struct pt_regs __regs)
Yoshinori Sato0983b312006-11-05 15:58:47 +0900617{
618 siginfo_t info;
619
Yoshinori Sato0983b312006-11-05 15:58:47 +0900620 switch (r4) {
621 case TRAP_DIVZERO_ERROR:
622 info.si_code = FPE_INTDIV;
623 break;
624 case TRAP_DIVOVF_ERROR:
625 info.si_code = FPE_INTOVF;
626 break;
627 }
628
629 force_sig_info(SIGFPE, &info, current);
630}
631#endif
632
Takashi YOSHII4b565682006-09-27 17:15:32 +0900633asmlinkage void do_reserved_inst(unsigned long r4, unsigned long r5,
634 unsigned long r6, unsigned long r7,
Stuart Menefyf0bc8142006-11-21 11:16:57 +0900635 struct pt_regs __regs)
Takashi YOSHII4b565682006-09-27 17:15:32 +0900636{
Stuart Menefyf0bc8142006-11-21 11:16:57 +0900637 struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
Takashi YOSHII4b565682006-09-27 17:15:32 +0900638 unsigned long error_code;
639 struct task_struct *tsk = current;
640
641#ifdef CONFIG_SH_FPU_EMU
Yoshinori Sato0983b312006-11-05 15:58:47 +0900642 unsigned short inst = 0;
Takashi YOSHII4b565682006-09-27 17:15:32 +0900643 int err;
644
Stuart Menefyf0bc8142006-11-21 11:16:57 +0900645 get_user(inst, (unsigned short*)regs->pc);
Takashi YOSHII4b565682006-09-27 17:15:32 +0900646
Stuart Menefyf0bc8142006-11-21 11:16:57 +0900647 err = do_fpu_inst(inst, regs);
Takashi YOSHII4b565682006-09-27 17:15:32 +0900648 if (!err) {
Paul Mundt53f983a2007-05-08 15:31:48 +0900649 regs->pc += instruction_size(inst);
Takashi YOSHII4b565682006-09-27 17:15:32 +0900650 return;
651 }
652 /* not a FPU inst. */
653#endif
654
655#ifdef CONFIG_SH_DSP
656 /* Check if it's a DSP instruction */
Stuart Menefyb5a1bcb2006-11-21 13:34:04 +0900657 if (is_dsp_inst(regs)) {
Takashi YOSHII4b565682006-09-27 17:15:32 +0900658 /* Enable DSP mode, and restart instruction. */
Stuart Menefyf0bc8142006-11-21 11:16:57 +0900659 regs->sr |= SR_DSP;
Michael Trimarchi01ab1032009-04-03 17:32:33 +0000660 /* Save DSP mode */
661 tsk->thread.dsp_status.status |= SR_DSP;
Takashi YOSHII4b565682006-09-27 17:15:32 +0900662 return;
663 }
664#endif
665
Paul Mundt4c59e292008-09-21 12:00:23 +0900666 error_code = lookup_exception_vector();
Yoshinori Sato0983b312006-11-05 15:58:47 +0900667
Takashi YOSHII4b565682006-09-27 17:15:32 +0900668 local_irq_enable();
Takashi YOSHII4b565682006-09-27 17:15:32 +0900669 force_sig(SIGILL, tsk);
Stuart Menefyf0bc8142006-11-21 11:16:57 +0900670 die_if_no_fixup("reserved instruction", regs, error_code);
Takashi YOSHII4b565682006-09-27 17:15:32 +0900671}
672
673#ifdef CONFIG_SH_FPU_EMU
Paul Mundtedfd6da2008-11-26 13:06:04 +0900674static int emulate_branch(unsigned short inst, struct pt_regs *regs)
Takashi YOSHII4b565682006-09-27 17:15:32 +0900675{
676 /*
677 * bfs: 8fxx: PC+=d*2+4;
678 * bts: 8dxx: PC+=d*2+4;
679 * bra: axxx: PC+=D*2+4;
680 * bsr: bxxx: PC+=D*2+4 after PR=PC+4;
681 * braf:0x23: PC+=Rn*2+4;
682 * bsrf:0x03: PC+=Rn*2+4 after PR=PC+4;
683 * jmp: 4x2b: PC=Rn;
684 * jsr: 4x0b: PC=Rn after PR=PC+4;
685 * rts: 000b: PC=PR;
686 */
Paul Mundtedfd6da2008-11-26 13:06:04 +0900687 if (((inst & 0xf000) == 0xb000) || /* bsr */
688 ((inst & 0xf0ff) == 0x0003) || /* bsrf */
689 ((inst & 0xf0ff) == 0x400b)) /* jsr */
690 regs->pr = regs->pc + 4;
691
692 if ((inst & 0xfd00) == 0x8d00) { /* bfs, bts */
Takashi YOSHII4b565682006-09-27 17:15:32 +0900693 regs->pc += SH_PC_8BIT_OFFSET(inst);
694 return 0;
695 }
696
Paul Mundtedfd6da2008-11-26 13:06:04 +0900697 if ((inst & 0xe000) == 0xa000) { /* bra, bsr */
Takashi YOSHII4b565682006-09-27 17:15:32 +0900698 regs->pc += SH_PC_12BIT_OFFSET(inst);
699 return 0;
700 }
701
Paul Mundtedfd6da2008-11-26 13:06:04 +0900702 if ((inst & 0xf0df) == 0x0003) { /* braf, bsrf */
Takashi YOSHII4b565682006-09-27 17:15:32 +0900703 regs->pc += regs->regs[(inst & 0x0f00) >> 8] + 4;
704 return 0;
705 }
706
Paul Mundtedfd6da2008-11-26 13:06:04 +0900707 if ((inst & 0xf0df) == 0x400b) { /* jmp, jsr */
Takashi YOSHII4b565682006-09-27 17:15:32 +0900708 regs->pc = regs->regs[(inst & 0x0f00) >> 8];
709 return 0;
710 }
711
Paul Mundtedfd6da2008-11-26 13:06:04 +0900712 if ((inst & 0xffff) == 0x000b) { /* rts */
Takashi YOSHII4b565682006-09-27 17:15:32 +0900713 regs->pc = regs->pr;
714 return 0;
715 }
716
717 return 1;
718}
719#endif
720
721asmlinkage void do_illegal_slot_inst(unsigned long r4, unsigned long r5,
722 unsigned long r6, unsigned long r7,
Stuart Menefyf0bc8142006-11-21 11:16:57 +0900723 struct pt_regs __regs)
Takashi YOSHII4b565682006-09-27 17:15:32 +0900724{
Stuart Menefyf0bc8142006-11-21 11:16:57 +0900725 struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
Paul Mundtb3d765f2008-09-17 23:12:11 +0900726 unsigned long inst;
Takashi YOSHII4b565682006-09-27 17:15:32 +0900727 struct task_struct *tsk = current;
Chris Smithd39f5452008-09-05 17:15:39 +0900728
729 if (kprobe_handle_illslot(regs->pc) == 0)
730 return;
731
Takashi YOSHII4b565682006-09-27 17:15:32 +0900732#ifdef CONFIG_SH_FPU_EMU
Stuart Menefyf0bc8142006-11-21 11:16:57 +0900733 get_user(inst, (unsigned short *)regs->pc + 1);
734 if (!do_fpu_inst(inst, regs)) {
735 get_user(inst, (unsigned short *)regs->pc);
736 if (!emulate_branch(inst, regs))
Takashi YOSHII4b565682006-09-27 17:15:32 +0900737 return;
738 /* fault in branch.*/
739 }
740 /* not a FPU inst. */
741#endif
742
Paul Mundt4c59e292008-09-21 12:00:23 +0900743 inst = lookup_exception_vector();
Yoshinori Sato0983b312006-11-05 15:58:47 +0900744
Takashi YOSHII4b565682006-09-27 17:15:32 +0900745 local_irq_enable();
Takashi YOSHII4b565682006-09-27 17:15:32 +0900746 force_sig(SIGILL, tsk);
Paul Mundtb3d765f2008-09-17 23:12:11 +0900747 die_if_no_fixup("illegal slot instruction", regs, inst);
Takashi YOSHII4b565682006-09-27 17:15:32 +0900748}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700749
750asmlinkage void do_exception_error(unsigned long r4, unsigned long r5,
751 unsigned long r6, unsigned long r7,
Stuart Menefyf0bc8142006-11-21 11:16:57 +0900752 struct pt_regs __regs)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700753{
Stuart Menefyf0bc8142006-11-21 11:16:57 +0900754 struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700755 long ex;
Yoshinori Sato0983b312006-11-05 15:58:47 +0900756
Paul Mundt4c59e292008-09-21 12:00:23 +0900757 ex = lookup_exception_vector();
Stuart Menefyf0bc8142006-11-21 11:16:57 +0900758 die_if_kernel("exception", regs, ex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700759}
760
761#if defined(CONFIG_SH_STANDARD_BIOS)
762void *gdb_vbr_vector;
763
764static inline void __init gdb_vbr_init(void)
765{
766 register unsigned long vbr;
767
768 /*
769 * Read the old value of the VBR register to initialise
770 * the vector through which debug and BIOS traps are
771 * delegated by the Linux trap handler.
772 */
773 asm volatile("stc vbr, %0" : "=r" (vbr));
774
775 gdb_vbr_vector = (void *)(vbr + 0x100);
776 printk("Setting GDB trap vector to 0x%08lx\n",
777 (unsigned long)gdb_vbr_vector);
778}
779#endif
780
Paul Mundtaba10302007-09-21 18:32:32 +0900781void __cpuinit per_cpu_trap_init(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700782{
783 extern void *vbr_base;
784
785#ifdef CONFIG_SH_STANDARD_BIOS
Paul Mundtaba10302007-09-21 18:32:32 +0900786 if (raw_smp_processor_id() == 0)
787 gdb_vbr_init();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700788#endif
789
790 /* NOTE: The VBR value should be at P1
791 (or P2, virtural "fixed" address space).
792 It's definitely should not in physical address. */
793
794 asm volatile("ldc %0, vbr"
795 : /* no output */
796 : "r" (&vbr_base)
797 : "memory");
798}
799
Paul Mundt1f666582006-10-19 16:20:25 +0900800void *set_exception_table_vec(unsigned int vec, void *handler)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700801{
802 extern void *exception_handling_table[];
Paul Mundt1f666582006-10-19 16:20:25 +0900803 void *old_handler;
Stuart Menefyb5a1bcb2006-11-21 13:34:04 +0900804
Paul Mundt1f666582006-10-19 16:20:25 +0900805 old_handler = exception_handling_table[vec];
806 exception_handling_table[vec] = handler;
807 return old_handler;
808}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700809
Paul Mundt1f666582006-10-19 16:20:25 +0900810void __init trap_init(void)
811{
812 set_exception_table_vec(TRAP_RESERVED_INST, do_reserved_inst);
813 set_exception_table_vec(TRAP_ILLEGAL_SLOT_INST, do_illegal_slot_inst);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700814
Takashi YOSHII4b565682006-09-27 17:15:32 +0900815#if defined(CONFIG_CPU_SH4) && !defined(CONFIG_SH_FPU) || \
816 defined(CONFIG_SH_FPU_EMU)
817 /*
818 * For SH-4 lacking an FPU, treat floating point instructions as
819 * reserved. They'll be handled in the math-emu case, or faulted on
820 * otherwise.
821 */
Paul Mundt1f666582006-10-19 16:20:25 +0900822 set_exception_table_evt(0x800, do_reserved_inst);
823 set_exception_table_evt(0x820, do_illegal_slot_inst);
824#elif defined(CONFIG_SH_FPU)
Paul Mundte0a36472007-08-01 16:55:07 +0900825#ifdef CONFIG_CPU_SUBTYPE_SHX3
Paul Mundt74d99a52007-11-26 20:38:36 +0900826 set_exception_table_evt(0xd80, fpu_state_restore_trap_handler);
827 set_exception_table_evt(0xda0, fpu_state_restore_trap_handler);
Paul Mundte0a36472007-08-01 16:55:07 +0900828#else
Paul Mundt74d99a52007-11-26 20:38:36 +0900829 set_exception_table_evt(0x800, fpu_state_restore_trap_handler);
830 set_exception_table_evt(0x820, fpu_state_restore_trap_handler);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700831#endif
Paul Mundte0a36472007-08-01 16:55:07 +0900832#endif
Yoshinori Sato0983b312006-11-05 15:58:47 +0900833
834#ifdef CONFIG_CPU_SH2
Paul Mundt5a4f7c62007-11-20 18:08:06 +0900835 set_exception_table_vec(TRAP_ADDRESS_ERROR, address_error_trap_handler);
Yoshinori Sato0983b312006-11-05 15:58:47 +0900836#endif
837#ifdef CONFIG_CPU_SH2A
838 set_exception_table_vec(TRAP_DIVZERO_ERROR, do_divide_error);
839 set_exception_table_vec(TRAP_DIVOVF_ERROR, do_divide_error);
Yoshinori Sato6e80f5e2008-07-10 01:20:03 +0900840#ifdef CONFIG_SH_FPU
841 set_exception_table_vec(TRAP_FPU_ERROR, fpu_error_trap_handler);
842#endif
Yoshinori Sato0983b312006-11-05 15:58:47 +0900843#endif
Stuart Menefyb5a1bcb2006-11-21 13:34:04 +0900844
Peter Griffincd894362009-05-08 15:51:51 +0100845#ifdef TRAP_UBC
846 set_exception_table_vec(TRAP_UBC, break_point_trap);
847#endif
848
Linus Torvalds1da177e2005-04-16 15:20:36 -0700849 /* Setup VBR for boot cpu */
850 per_cpu_trap_init();
851}
852
853void show_stack(struct task_struct *tsk, unsigned long *sp)
854{
Paul Mundt6b002232006-10-12 17:07:45 +0900855 unsigned long stack;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700856
Paul Mundta6a311392006-09-27 18:22:14 +0900857 if (!tsk)
858 tsk = current;
859 if (tsk == current)
860 sp = (unsigned long *)current_stack_pointer;
861 else
Linus Torvalds1da177e2005-04-16 15:20:36 -0700862 sp = (unsigned long *)tsk->thread.sp;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700863
Paul Mundt6b002232006-10-12 17:07:45 +0900864 stack = (unsigned long)sp;
865 dump_mem("Stack: ", stack, THREAD_SIZE +
866 (unsigned long)task_stack_page(tsk));
867 show_trace(tsk, sp, NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700868}
869
870void dump_stack(void)
871{
872 show_stack(NULL, NULL);
873}
874EXPORT_SYMBOL(dump_stack);