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-rw-r--r--arch/sh/kernel/traps.c949
1 files changed, 35 insertions, 914 deletions
diff --git a/arch/sh/kernel/traps.c b/arch/sh/kernel/traps.c
index cf99111cb33f..a3bdc68ef02c 100644
--- a/arch/sh/kernel/traps.c
+++ b/arch/sh/kernel/traps.c
@@ -1,947 +1,68 @@
1/*
2 * 'traps.c' handles hardware traps and faults after we have saved some
3 * state in 'entry.S'.
4 *
5 * SuperH version: Copyright (C) 1999 Niibe Yutaka
6 * Copyright (C) 2000 Philipp Rumpf
7 * Copyright (C) 2000 David Howells
8 * Copyright (C) 2002 - 2007 Paul Mundt
9 *
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.
13 */
14#include <linux/kernel.h>
15#include <linux/ptrace.h>
16#include <linux/init.h>
17#include <linux/spinlock.h>
18#include <linux/module.h>
19#include <linux/kallsyms.h>
20#include <linux/io.h>
21#include <linux/bug.h> 1#include <linux/bug.h>
22#include <linux/debug_locks.h> 2#include <linux/io.h>
3#include <linux/types.h>
23#include <linux/kdebug.h> 4#include <linux/kdebug.h>
24#include <linux/kexec.h> 5#include <linux/signal.h>
25#include <linux/limits.h> 6#include <linux/sched.h>
26#include <asm/system.h> 7#include <asm/system.h>
27#include <asm/uaccess.h>
28
29#ifdef CONFIG_SH_KGDB
30#include <asm/kgdb.h>
31#define CHK_REMOTE_DEBUG(regs) \
32{ \
33 if (kgdb_debug_hook && !user_mode(regs))\
34 (*kgdb_debug_hook)(regs); \
35}
36#else
37#define CHK_REMOTE_DEBUG(regs)
38#endif
39
40#ifdef CONFIG_CPU_SH2
41# define TRAP_RESERVED_INST 4
42# define TRAP_ILLEGAL_SLOT_INST 6
43# define TRAP_ADDRESS_ERROR 9
44# ifdef CONFIG_CPU_SH2A
45# define TRAP_DIVZERO_ERROR 17
46# define TRAP_DIVOVF_ERROR 18
47# endif
48#else
49#define TRAP_RESERVED_INST 12
50#define TRAP_ILLEGAL_SLOT_INST 13
51#endif
52
53static void dump_mem(const char *str, unsigned long bottom, unsigned long top)
54{
55 unsigned long p;
56 int i;
57
58 printk("%s(0x%08lx to 0x%08lx)\n", str, bottom, top);
59
60 for (p = bottom & ~31; p < top; ) {
61 printk("%04lx: ", p & 0xffff);
62
63 for (i = 0; i < 8; i++, p += 4) {
64 unsigned int val;
65
66 if (p < bottom || p >= top)
67 printk(" ");
68 else {
69 if (__get_user(val, (unsigned int __user *)p)) {
70 printk("\n");
71 return;
72 }
73 printk("%08x ", val);
74 }
75 }
76 printk("\n");
77 }
78}
79
80static DEFINE_SPINLOCK(die_lock);
81
82void die(const char * str, struct pt_regs * regs, long err)
83{
84 static int die_counter;
85
86 oops_enter();
87
88 console_verbose();
89 spin_lock_irq(&die_lock);
90 bust_spinlocks(1);
91
92 printk("%s: %04lx [#%d]\n", str, err & 0xffff, ++die_counter);
93
94 CHK_REMOTE_DEBUG(regs);
95 print_modules();
96 show_regs(regs);
97
98 printk("Process: %s (pid: %d, stack limit = %p)\n", current->comm,
99 task_pid_nr(current), task_stack_page(current) + 1);
100
101 if (!user_mode(regs) || in_interrupt())
102 dump_mem("Stack: ", regs->regs[15], THREAD_SIZE +
103 (unsigned long)task_stack_page(current));
104
105 bust_spinlocks(0);
106 add_taint(TAINT_DIE);
107 spin_unlock_irq(&die_lock);
108
109 if (kexec_should_crash(current))
110 crash_kexec(regs);
111
112 if (in_interrupt())
113 panic("Fatal exception in interrupt");
114
115 if (panic_on_oops)
116 panic("Fatal exception");
117
118 oops_exit();
119 do_exit(SIGSEGV);
120}
121
122static inline void die_if_kernel(const char *str, struct pt_regs *regs,
123 long err)
124{
125 if (!user_mode(regs))
126 die(str, regs, err);
127}
128
129/*
130 * try and fix up kernelspace address errors
131 * - userspace errors just cause EFAULT to be returned, resulting in SEGV
132 * - kernel/userspace interfaces cause a jump to an appropriate handler
133 * - other kernel errors are bad
134 * - return 0 if fixed-up, -EFAULT if non-fatal (to the kernel) fault
135 */
136static int die_if_no_fixup(const char * str, struct pt_regs * regs, long err)
137{
138 if (!user_mode(regs)) {
139 const struct exception_table_entry *fixup;
140 fixup = search_exception_tables(regs->pc);
141 if (fixup) {
142 regs->pc = fixup->fixup;
143 return 0;
144 }
145 die(str, regs, err);
146 }
147 return -EFAULT;
148}
149
150/*
151 * handle an instruction that does an unaligned memory access by emulating the
152 * desired behaviour
153 * - note that PC _may not_ point to the faulting instruction
154 * (if that instruction is in a branch delay slot)
155 * - return 0 if emulation okay, -EFAULT on existential error
156 */
157static int handle_unaligned_ins(u16 instruction, struct pt_regs *regs)
158{
159 int ret, index, count;
160 unsigned long *rm, *rn;
161 unsigned char *src, *dst;
162
163 index = (instruction>>8)&15; /* 0x0F00 */
164 rn = &regs->regs[index];
165
166 index = (instruction>>4)&15; /* 0x00F0 */
167 rm = &regs->regs[index];
168
169 count = 1<<(instruction&3);
170
171 ret = -EFAULT;
172 switch (instruction>>12) {
173 case 0: /* mov.[bwl] to/from memory via r0+rn */
174 if (instruction & 8) {
175 /* from memory */
176 src = (unsigned char*) *rm;
177 src += regs->regs[0];
178 dst = (unsigned char*) rn;
179 *(unsigned long*)dst = 0;
180
181#ifdef __LITTLE_ENDIAN__
182 if (copy_from_user(dst, src, count))
183 goto fetch_fault;
184
185 if ((count == 2) && dst[1] & 0x80) {
186 dst[2] = 0xff;
187 dst[3] = 0xff;
188 }
189#else
190 dst += 4-count;
191
192 if (__copy_user(dst, src, count))
193 goto fetch_fault;
194
195 if ((count == 2) && dst[2] & 0x80) {
196 dst[0] = 0xff;
197 dst[1] = 0xff;
198 }
199#endif
200 } else {
201 /* to memory */
202 src = (unsigned char*) rm;
203#if !defined(__LITTLE_ENDIAN__)
204 src += 4-count;
205#endif
206 dst = (unsigned char*) *rn;
207 dst += regs->regs[0];
208
209 if (copy_to_user(dst, src, count))
210 goto fetch_fault;
211 }
212 ret = 0;
213 break;
214
215 case 1: /* mov.l Rm,@(disp,Rn) */
216 src = (unsigned char*) rm;
217 dst = (unsigned char*) *rn;
218 dst += (instruction&0x000F)<<2;
219
220 if (copy_to_user(dst,src,4))
221 goto fetch_fault;
222 ret = 0;
223 break;
224
225 case 2: /* mov.[bwl] to memory, possibly with pre-decrement */
226 if (instruction & 4)
227 *rn -= count;
228 src = (unsigned char*) rm;
229 dst = (unsigned char*) *rn;
230#if !defined(__LITTLE_ENDIAN__)
231 src += 4-count;
232#endif
233 if (copy_to_user(dst, src, count))
234 goto fetch_fault;
235 ret = 0;
236 break;
237
238 case 5: /* mov.l @(disp,Rm),Rn */
239 src = (unsigned char*) *rm;
240 src += (instruction&0x000F)<<2;
241 dst = (unsigned char*) rn;
242 *(unsigned long*)dst = 0;
243
244 if (copy_from_user(dst,src,4))
245 goto fetch_fault;
246 ret = 0;
247 break;
248 8
249 case 6: /* mov.[bwl] from memory, possibly with post-increment */ 9#ifdef CONFIG_BUG
250 src = (unsigned char*) *rm; 10static void handle_BUG(struct pt_regs *regs)
251 if (instruction & 4)
252 *rm += count;
253 dst = (unsigned char*) rn;
254 *(unsigned long*)dst = 0;
255
256#ifdef __LITTLE_ENDIAN__
257 if (copy_from_user(dst, src, count))
258 goto fetch_fault;
259
260 if ((count == 2) && dst[1] & 0x80) {
261 dst[2] = 0xff;
262 dst[3] = 0xff;
263 }
264#else
265 dst += 4-count;
266
267 if (copy_from_user(dst, src, count))
268 goto fetch_fault;
269
270 if ((count == 2) && dst[2] & 0x80) {
271 dst[0] = 0xff;
272 dst[1] = 0xff;
273 }
274#endif
275 ret = 0;
276 break;
277
278 case 8:
279 switch ((instruction&0xFF00)>>8) {
280 case 0x81: /* mov.w R0,@(disp,Rn) */
281 src = (unsigned char*) &regs->regs[0];
282#if !defined(__LITTLE_ENDIAN__)
283 src += 2;
284#endif
285 dst = (unsigned char*) *rm; /* called Rn in the spec */
286 dst += (instruction&0x000F)<<1;
287
288 if (copy_to_user(dst, src, 2))
289 goto fetch_fault;
290 ret = 0;
291 break;
292
293 case 0x85: /* mov.w @(disp,Rm),R0 */
294 src = (unsigned char*) *rm;
295 src += (instruction&0x000F)<<1;
296 dst = (unsigned char*) &regs->regs[0];
297 *(unsigned long*)dst = 0;
298
299#if !defined(__LITTLE_ENDIAN__)
300 dst += 2;
301#endif
302
303 if (copy_from_user(dst, src, 2))
304 goto fetch_fault;
305
306#ifdef __LITTLE_ENDIAN__
307 if (dst[1] & 0x80) {
308 dst[2] = 0xff;
309 dst[3] = 0xff;
310 }
311#else
312 if (dst[2] & 0x80) {
313 dst[0] = 0xff;
314 dst[1] = 0xff;
315 }
316#endif
317 ret = 0;
318 break;
319 }
320 break;
321 }
322 return ret;
323
324 fetch_fault:
325 /* Argh. Address not only misaligned but also non-existent.
326 * Raise an EFAULT and see if it's trapped
327 */
328 return die_if_no_fixup("Fault in unaligned fixup", regs, 0);
329}
330
331/*
332 * emulate the instruction in the delay slot
333 * - fetches the instruction from PC+2
334 */
335static inline int handle_unaligned_delayslot(struct pt_regs *regs)
336{ 11{
337 u16 instruction; 12 enum bug_trap_type tt;
338 13 tt = report_bug(regs->pc, regs);
339 if (copy_from_user(&instruction, (u16 *)(regs->pc+2), 2)) { 14 if (tt == BUG_TRAP_TYPE_WARN) {
340 /* the instruction-fetch faulted */ 15 regs->pc += instruction_size(regs->pc);
341 if (user_mode(regs)) 16 return;
342 return -EFAULT;
343
344 /* kernel */
345 die("delay-slot-insn faulting in handle_unaligned_delayslot",
346 regs, 0);
347 } 17 }
348 18
349 return handle_unaligned_ins(instruction,regs); 19 die("Kernel BUG", regs, TRAPA_BUG_OPCODE & 0xff);
350} 20}
351 21
352/* 22int is_valid_bugaddr(unsigned long addr)
353 * handle an instruction that does an unaligned memory access
354 * - have to be careful of branch delay-slot instructions that fault
355 * SH3:
356 * - if the branch would be taken PC points to the branch
357 * - if the branch would not be taken, PC points to delay-slot
358 * SH4:
359 * - PC always points to delayed branch
360 * - return 0 if handled, -EFAULT if failed (may not return if in kernel)
361 */
362
363/* Macros to determine offset from current PC for branch instructions */
364/* Explicit type coercion is used to force sign extension where needed */
365#define SH_PC_8BIT_OFFSET(instr) ((((signed char)(instr))*2) + 4)
366#define SH_PC_12BIT_OFFSET(instr) ((((signed short)(instr<<4))>>3) + 4)
367
368/*
369 * XXX: SH-2A needs this too, but it needs an overhaul thanks to mixed 32-bit
370 * opcodes..
371 */
372#ifndef CONFIG_CPU_SH2A
373static int handle_unaligned_notify_count = 10;
374
375static int handle_unaligned_access(u16 instruction, struct pt_regs *regs)
376{ 23{
377 u_int rm; 24 return addr >= PAGE_OFFSET;
378 int ret, index;
379
380 index = (instruction>>8)&15; /* 0x0F00 */
381 rm = regs->regs[index];
382
383 /* shout about the first ten userspace fixups */
384 if (user_mode(regs) && handle_unaligned_notify_count>0) {
385 handle_unaligned_notify_count--;
386
387 printk(KERN_NOTICE "Fixing up unaligned userspace access "
388 "in \"%s\" pid=%d pc=0x%p ins=0x%04hx\n",
389 current->comm, task_pid_nr(current),
390 (u16 *)regs->pc, instruction);
391 }
392
393 ret = -EFAULT;
394 switch (instruction&0xF000) {
395 case 0x0000:
396 if (instruction==0x000B) {
397 /* rts */
398 ret = handle_unaligned_delayslot(regs);
399 if (ret==0)
400 regs->pc = regs->pr;
401 }
402 else if ((instruction&0x00FF)==0x0023) {
403 /* braf @Rm */
404 ret = handle_unaligned_delayslot(regs);
405 if (ret==0)
406 regs->pc += rm + 4;
407 }
408 else if ((instruction&0x00FF)==0x0003) {
409 /* bsrf @Rm */
410 ret = handle_unaligned_delayslot(regs);
411 if (ret==0) {
412 regs->pr = regs->pc + 4;
413 regs->pc += rm + 4;
414 }
415 }
416 else {
417 /* mov.[bwl] to/from memory via r0+rn */
418 goto simple;
419 }
420 break;
421
422 case 0x1000: /* mov.l Rm,@(disp,Rn) */
423 goto simple;
424
425 case 0x2000: /* mov.[bwl] to memory, possibly with pre-decrement */
426 goto simple;
427
428 case 0x4000:
429 if ((instruction&0x00FF)==0x002B) {
430 /* jmp @Rm */
431 ret = handle_unaligned_delayslot(regs);
432 if (ret==0)
433 regs->pc = rm;
434 }
435 else if ((instruction&0x00FF)==0x000B) {
436 /* jsr @Rm */
437 ret = handle_unaligned_delayslot(regs);
438 if (ret==0) {
439 regs->pr = regs->pc + 4;
440 regs->pc = rm;
441 }
442 }
443 else {
444 /* mov.[bwl] to/from memory via r0+rn */
445 goto simple;
446 }
447 break;
448
449 case 0x5000: /* mov.l @(disp,Rm),Rn */
450 goto simple;
451
452 case 0x6000: /* mov.[bwl] from memory, possibly with post-increment */
453 goto simple;
454
455 case 0x8000: /* bf lab, bf/s lab, bt lab, bt/s lab */
456 switch (instruction&0x0F00) {
457 case 0x0100: /* mov.w R0,@(disp,Rm) */
458 goto simple;
459 case 0x0500: /* mov.w @(disp,Rm),R0 */
460 goto simple;
461 case 0x0B00: /* bf lab - no delayslot*/
462 break;
463 case 0x0F00: /* bf/s lab */
464 ret = handle_unaligned_delayslot(regs);
465 if (ret==0) {
466#if defined(CONFIG_CPU_SH4) || defined(CONFIG_SH7705_CACHE_32KB)
467 if ((regs->sr & 0x00000001) != 0)
468 regs->pc += 4; /* next after slot */
469 else
470#endif
471 regs->pc += SH_PC_8BIT_OFFSET(instruction);
472 }
473 break;
474 case 0x0900: /* bt lab - no delayslot */
475 break;
476 case 0x0D00: /* bt/s lab */
477 ret = handle_unaligned_delayslot(regs);
478 if (ret==0) {
479#if defined(CONFIG_CPU_SH4) || defined(CONFIG_SH7705_CACHE_32KB)
480 if ((regs->sr & 0x00000001) == 0)
481 regs->pc += 4; /* next after slot */
482 else
483#endif
484 regs->pc += SH_PC_8BIT_OFFSET(instruction);
485 }
486 break;
487 }
488 break;
489
490 case 0xA000: /* bra label */
491 ret = handle_unaligned_delayslot(regs);
492 if (ret==0)
493 regs->pc += SH_PC_12BIT_OFFSET(instruction);
494 break;
495
496 case 0xB000: /* bsr label */
497 ret = handle_unaligned_delayslot(regs);
498 if (ret==0) {
499 regs->pr = regs->pc + 4;
500 regs->pc += SH_PC_12BIT_OFFSET(instruction);
501 }
502 break;
503 }
504 return ret;
505
506 /* handle non-delay-slot instruction */
507 simple:
508 ret = handle_unaligned_ins(instruction,regs);
509 if (ret==0)
510 regs->pc += instruction_size(instruction);
511 return ret;
512} 25}
513#endif /* CONFIG_CPU_SH2A */
514
515#ifdef CONFIG_CPU_HAS_SR_RB
516#define lookup_exception_vector(x) \
517 __asm__ __volatile__ ("stc r2_bank, %0\n\t" : "=r" ((x)))
518#else
519#define lookup_exception_vector(x) \
520 __asm__ __volatile__ ("mov r4, %0\n\t" : "=r" ((x)))
521#endif 26#endif
522 27
523/* 28/*
524 * Handle various address error exceptions: 29 * Generic trap handler.
525 * - instruction address error:
526 * misaligned PC
527 * PC >= 0x80000000 in user mode
528 * - data address error (read and write)
529 * misaligned data access
530 * access to >= 0x80000000 is user mode
531 * Unfortuntaly we can't distinguish between instruction address error
532 * and data address errors caused by read accesses.
533 */ 30 */
534asmlinkage void do_address_error(struct pt_regs *regs, 31BUILD_TRAP_HANDLER(debug)
535 unsigned long writeaccess,
536 unsigned long address)
537{ 32{
538 unsigned long error_code = 0; 33 TRAP_HANDLER_DECL;
539 mm_segment_t oldfs;
540 siginfo_t info;
541#ifndef CONFIG_CPU_SH2A
542 u16 instruction;
543 int tmp;
544#endif
545
546 /* Intentional ifdef */
547#ifdef CONFIG_CPU_HAS_SR_RB
548 lookup_exception_vector(error_code);
549#endif
550
551 oldfs = get_fs();
552
553 if (user_mode(regs)) {
554 int si_code = BUS_ADRERR;
555
556 local_irq_enable();
557 34
558 /* bad PC is not something we can fix */ 35 /* Rewind */
559 if (regs->pc & 1) { 36 regs->pc -= instruction_size(ctrl_inw(regs->pc - 4));
560 si_code = BUS_ADRALN;
561 goto uspace_segv;
562 }
563 37
564#ifndef CONFIG_CPU_SH2A 38 if (notify_die(DIE_TRAP, "debug trap", regs, 0, vec & 0xff,
565 set_fs(USER_DS); 39 SIGTRAP) == NOTIFY_STOP)
566 if (copy_from_user(&instruction, (u16 *)(regs->pc), 2)) { 40 return;
567 /* Argh. Fault on the instruction itself.
568 This should never happen non-SMP
569 */
570 set_fs(oldfs);
571 goto uspace_segv;
572 }
573
574 tmp = handle_unaligned_access(instruction, regs);
575 set_fs(oldfs);
576
577 if (tmp==0)
578 return; /* sorted */
579#endif
580
581uspace_segv:
582 printk(KERN_NOTICE "Sending SIGBUS to \"%s\" due to unaligned "
583 "access (PC %lx PR %lx)\n", current->comm, regs->pc,
584 regs->pr);
585
586 info.si_signo = SIGBUS;
587 info.si_errno = 0;
588 info.si_code = si_code;
589 info.si_addr = (void __user *)address;
590 force_sig_info(SIGBUS, &info, current);
591 } else {
592 if (regs->pc & 1)
593 die("unaligned program counter", regs, error_code);
594
595#ifndef CONFIG_CPU_SH2A
596 set_fs(KERNEL_DS);
597 if (copy_from_user(&instruction, (u16 *)(regs->pc), 2)) {
598 /* Argh. Fault on the instruction itself.
599 This should never happen non-SMP
600 */
601 set_fs(oldfs);
602 die("insn faulting in do_address_error", regs, 0);
603 }
604
605 handle_unaligned_access(instruction, regs);
606 set_fs(oldfs);
607#else
608 printk(KERN_NOTICE "Killing process \"%s\" due to unaligned "
609 "access\n", current->comm);
610 41
611 force_sig(SIGSEGV, current); 42 force_sig(SIGTRAP, current);
612#endif
613 }
614} 43}
615 44
616#ifdef CONFIG_SH_DSP
617/* 45/*
618 * SH-DSP support gerg@snapgear.com. 46 * Special handler for BUG() traps.
619 */ 47 */
620int is_dsp_inst(struct pt_regs *regs) 48BUILD_TRAP_HANDLER(bug)
621{ 49{
622 unsigned short inst = 0; 50 TRAP_HANDLER_DECL;
623
624 /*
625 * Safe guard if DSP mode is already enabled or we're lacking
626 * the DSP altogether.
627 */
628 if (!(current_cpu_data.flags & CPU_HAS_DSP) || (regs->sr & SR_DSP))
629 return 0;
630
631 get_user(inst, ((unsigned short *) regs->pc));
632
633 inst &= 0xf000;
634
635 /* Check for any type of DSP or support instruction */
636 if ((inst == 0xf000) || (inst == 0x4000))
637 return 1;
638
639 return 0;
640}
641#else
642#define is_dsp_inst(regs) (0)
643#endif /* CONFIG_SH_DSP */
644 51
645#ifdef CONFIG_CPU_SH2A 52 /* Rewind */
646asmlinkage void do_divide_error(unsigned long r4, unsigned long r5, 53 regs->pc -= instruction_size(ctrl_inw(regs->pc - 4));
647 unsigned long r6, unsigned long r7,
648 struct pt_regs __regs)
649{
650 siginfo_t info;
651
652 switch (r4) {
653 case TRAP_DIVZERO_ERROR:
654 info.si_code = FPE_INTDIV;
655 break;
656 case TRAP_DIVOVF_ERROR:
657 info.si_code = FPE_INTOVF;
658 break;
659 }
660
661 force_sig_info(SIGFPE, &info, current);
662}
663#endif
664
665/* arch/sh/kernel/cpu/sh4/fpu.c */
666extern int do_fpu_inst(unsigned short, struct pt_regs *);
667extern asmlinkage void do_fpu_state_restore(unsigned long r4, unsigned long r5,
668 unsigned long r6, unsigned long r7, struct pt_regs __regs);
669
670asmlinkage void do_reserved_inst(unsigned long r4, unsigned long r5,
671 unsigned long r6, unsigned long r7,
672 struct pt_regs __regs)
673{
674 struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
675 unsigned long error_code;
676 struct task_struct *tsk = current;
677
678#ifdef CONFIG_SH_FPU_EMU
679 unsigned short inst = 0;
680 int err;
681
682 get_user(inst, (unsigned short*)regs->pc);
683
684 err = do_fpu_inst(inst, regs);
685 if (!err) {
686 regs->pc += instruction_size(inst);
687 return;
688 }
689 /* not a FPU inst. */
690#endif
691 54
692#ifdef CONFIG_SH_DSP 55 if (notify_die(DIE_TRAP, "bug trap", regs, 0, TRAPA_BUG_OPCODE & 0xff,
693 /* Check if it's a DSP instruction */ 56 SIGTRAP) == NOTIFY_STOP)
694 if (is_dsp_inst(regs)) {
695 /* Enable DSP mode, and restart instruction. */
696 regs->sr |= SR_DSP;
697 return; 57 return;
698 }
699#endif
700
701 lookup_exception_vector(error_code);
702
703 local_irq_enable();
704 CHK_REMOTE_DEBUG(regs);
705 force_sig(SIGILL, tsk);
706 die_if_no_fixup("reserved instruction", regs, error_code);
707}
708
709#ifdef CONFIG_SH_FPU_EMU
710static int emulate_branch(unsigned short inst, struct pt_regs* regs)
711{
712 /*
713 * bfs: 8fxx: PC+=d*2+4;
714 * bts: 8dxx: PC+=d*2+4;
715 * bra: axxx: PC+=D*2+4;
716 * bsr: bxxx: PC+=D*2+4 after PR=PC+4;
717 * braf:0x23: PC+=Rn*2+4;
718 * bsrf:0x03: PC+=Rn*2+4 after PR=PC+4;
719 * jmp: 4x2b: PC=Rn;
720 * jsr: 4x0b: PC=Rn after PR=PC+4;
721 * rts: 000b: PC=PR;
722 */
723 if ((inst & 0xfd00) == 0x8d00) {
724 regs->pc += SH_PC_8BIT_OFFSET(inst);
725 return 0;
726 }
727
728 if ((inst & 0xe000) == 0xa000) {
729 regs->pc += SH_PC_12BIT_OFFSET(inst);
730 return 0;
731 }
732
733 if ((inst & 0xf0df) == 0x0003) {
734 regs->pc += regs->regs[(inst & 0x0f00) >> 8] + 4;
735 return 0;
736 }
737
738 if ((inst & 0xf0df) == 0x400b) {
739 regs->pc = regs->regs[(inst & 0x0f00) >> 8];
740 return 0;
741 }
742
743 if ((inst & 0xffff) == 0x000b) {
744 regs->pc = regs->pr;
745 return 0;
746 }
747
748 return 1;
749}
750#endif
751
752asmlinkage void do_illegal_slot_inst(unsigned long r4, unsigned long r5,
753 unsigned long r6, unsigned long r7,
754 struct pt_regs __regs)
755{
756 struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
757 unsigned long error_code;
758 struct task_struct *tsk = current;
759#ifdef CONFIG_SH_FPU_EMU
760 unsigned short inst = 0;
761
762 get_user(inst, (unsigned short *)regs->pc + 1);
763 if (!do_fpu_inst(inst, regs)) {
764 get_user(inst, (unsigned short *)regs->pc);
765 if (!emulate_branch(inst, regs))
766 return;
767 /* fault in branch.*/
768 }
769 /* not a FPU inst. */
770#endif
771
772 lookup_exception_vector(error_code);
773
774 local_irq_enable();
775 CHK_REMOTE_DEBUG(regs);
776 force_sig(SIGILL, tsk);
777 die_if_no_fixup("illegal slot instruction", regs, error_code);
778}
779
780asmlinkage void do_exception_error(unsigned long r4, unsigned long r5,
781 unsigned long r6, unsigned long r7,
782 struct pt_regs __regs)
783{
784 struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
785 long ex;
786
787 lookup_exception_vector(ex);
788 die_if_kernel("exception", regs, ex);
789}
790
791#if defined(CONFIG_SH_STANDARD_BIOS)
792void *gdb_vbr_vector;
793
794static inline void __init gdb_vbr_init(void)
795{
796 register unsigned long vbr;
797
798 /*
799 * Read the old value of the VBR register to initialise
800 * the vector through which debug and BIOS traps are
801 * delegated by the Linux trap handler.
802 */
803 asm volatile("stc vbr, %0" : "=r" (vbr));
804
805 gdb_vbr_vector = (void *)(vbr + 0x100);
806 printk("Setting GDB trap vector to 0x%08lx\n",
807 (unsigned long)gdb_vbr_vector);
808}
809#endif
810
811void __cpuinit per_cpu_trap_init(void)
812{
813 extern void *vbr_base;
814
815#ifdef CONFIG_SH_STANDARD_BIOS
816 if (raw_smp_processor_id() == 0)
817 gdb_vbr_init();
818#endif
819
820 /* NOTE: The VBR value should be at P1
821 (or P2, virtural "fixed" address space).
822 It's definitely should not in physical address. */
823
824 asm volatile("ldc %0, vbr"
825 : /* no output */
826 : "r" (&vbr_base)
827 : "memory");
828}
829
830void *set_exception_table_vec(unsigned int vec, void *handler)
831{
832 extern void *exception_handling_table[];
833 void *old_handler;
834
835 old_handler = exception_handling_table[vec];
836 exception_handling_table[vec] = handler;
837 return old_handler;
838}
839
840extern asmlinkage void address_error_handler(unsigned long r4, unsigned long r5,
841 unsigned long r6, unsigned long r7,
842 struct pt_regs __regs);
843
844void __init trap_init(void)
845{
846 set_exception_table_vec(TRAP_RESERVED_INST, do_reserved_inst);
847 set_exception_table_vec(TRAP_ILLEGAL_SLOT_INST, do_illegal_slot_inst);
848
849#if defined(CONFIG_CPU_SH4) && !defined(CONFIG_SH_FPU) || \
850 defined(CONFIG_SH_FPU_EMU)
851 /*
852 * For SH-4 lacking an FPU, treat floating point instructions as
853 * reserved. They'll be handled in the math-emu case, or faulted on
854 * otherwise.
855 */
856 set_exception_table_evt(0x800, do_reserved_inst);
857 set_exception_table_evt(0x820, do_illegal_slot_inst);
858#elif defined(CONFIG_SH_FPU)
859#ifdef CONFIG_CPU_SUBTYPE_SHX3
860 set_exception_table_evt(0xd80, do_fpu_state_restore);
861 set_exception_table_evt(0xda0, do_fpu_state_restore);
862#else
863 set_exception_table_evt(0x800, do_fpu_state_restore);
864 set_exception_table_evt(0x820, do_fpu_state_restore);
865#endif
866#endif
867
868#ifdef CONFIG_CPU_SH2
869 set_exception_table_vec(TRAP_ADDRESS_ERROR, address_error_handler);
870#endif
871#ifdef CONFIG_CPU_SH2A
872 set_exception_table_vec(TRAP_DIVZERO_ERROR, do_divide_error);
873 set_exception_table_vec(TRAP_DIVOVF_ERROR, do_divide_error);
874#endif
875
876 /* Setup VBR for boot cpu */
877 per_cpu_trap_init();
878}
879 58
880#ifdef CONFIG_BUG 59#ifdef CONFIG_BUG
881void handle_BUG(struct pt_regs *regs) 60 if (__kernel_text_address(instruction_pointer(regs))) {
882{ 61 opcode_t insn = *(opcode_t *)instruction_pointer(regs);
883 enum bug_trap_type tt; 62 if (insn == TRAPA_BUG_OPCODE)
884 tt = report_bug(regs->pc, regs); 63 handle_BUG(regs);
885 if (tt == BUG_TRAP_TYPE_WARN) {
886 regs->pc += 2;
887 return;
888 } 64 }
889
890 die("Kernel BUG", regs, TRAPA_BUG_OPCODE & 0xff);
891}
892
893int is_valid_bugaddr(unsigned long addr)
894{
895 return addr >= PAGE_OFFSET;
896}
897#endif
898
899void show_trace(struct task_struct *tsk, unsigned long *sp,
900 struct pt_regs *regs)
901{
902 unsigned long addr;
903
904 if (regs && user_mode(regs))
905 return;
906
907 printk("\nCall trace: ");
908#ifdef CONFIG_KALLSYMS
909 printk("\n");
910#endif 65#endif
911 66
912 while (!kstack_end(sp)) { 67 force_sig(SIGTRAP, current);
913 addr = *sp++;
914 if (kernel_text_address(addr))
915 print_ip_sym(addr);
916 }
917
918 printk("\n");
919
920 if (!tsk)
921 tsk = current;
922
923 debug_show_held_locks(tsk);
924}
925
926void show_stack(struct task_struct *tsk, unsigned long *sp)
927{
928 unsigned long stack;
929
930 if (!tsk)
931 tsk = current;
932 if (tsk == current)
933 sp = (unsigned long *)current_stack_pointer;
934 else
935 sp = (unsigned long *)tsk->thread.sp;
936
937 stack = (unsigned long)sp;
938 dump_mem("Stack: ", stack, THREAD_SIZE +
939 (unsigned long)task_stack_page(tsk));
940 show_trace(tsk, sp, NULL);
941}
942
943void dump_stack(void)
944{
945 show_stack(NULL, NULL);
946} 68}
947EXPORT_SYMBOL(dump_stack);
generated by cgit v1.2.2 (git 2.25.0) at 2024-11-24 05:17:58 -0500