mm: fix exec activate_mm vs TLB shootdown and lazy tlb switching race
[linux/fpc-iii.git] / arch / mn10300 / kernel / traps.c
blob800fd08019698a20c17e7a9999bcd98ee2887f79
1 /* MN10300 Exception handling
3 * Copyright (C) 2007 Matsushita Electric Industrial Co., Ltd.
4 * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
5 * Modified by David Howells (dhowells@redhat.com)
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public Licence
9 * as published by the Free Software Foundation; either version
10 * 2 of the Licence, or (at your option) any later version.
12 #include <linux/sched.h>
13 #include <linux/sched/debug.h>
14 #include <linux/kernel.h>
15 #include <linux/string.h>
16 #include <linux/errno.h>
17 #include <linux/ptrace.h>
18 #include <linux/timer.h>
19 #include <linux/mm.h>
20 #include <linux/smp.h>
21 #include <linux/init.h>
22 #include <linux/delay.h>
23 #include <linux/spinlock.h>
24 #include <linux/interrupt.h>
25 #include <linux/kallsyms.h>
26 #include <linux/pci.h>
27 #include <linux/kdebug.h>
28 #include <linux/bug.h>
29 #include <linux/irq.h>
30 #include <linux/export.h>
31 #include <asm/processor.h>
32 #include <linux/uaccess.h>
33 #include <asm/io.h>
34 #include <linux/atomic.h>
35 #include <asm/smp.h>
36 #include <asm/pgalloc.h>
37 #include <asm/cacheflush.h>
38 #include <asm/cpu-regs.h>
39 #include <asm/busctl-regs.h>
40 #include <unit/leds.h>
41 #include <asm/fpu.h>
42 #include <asm/sections.h>
43 #include <asm/debugger.h>
44 #include "internal.h"
46 #if (CONFIG_INTERRUPT_VECTOR_BASE & 0xffffff)
47 #error "INTERRUPT_VECTOR_BASE not aligned to 16MiB boundary!"
48 #endif
50 int kstack_depth_to_print = 24;
52 spinlock_t die_lock = __SPIN_LOCK_UNLOCKED(die_lock);
54 struct exception_to_signal_map {
55 u8 signo;
56 u32 si_code;
59 static const struct exception_to_signal_map exception_to_signal_map[256] = {
60 /* MMU exceptions */
61 [EXCEP_ITLBMISS >> 3] = { 0, 0 },
62 [EXCEP_DTLBMISS >> 3] = { 0, 0 },
63 [EXCEP_IAERROR >> 3] = { 0, 0 },
64 [EXCEP_DAERROR >> 3] = { 0, 0 },
66 /* system exceptions */
67 [EXCEP_TRAP >> 3] = { SIGTRAP, TRAP_BRKPT },
68 [EXCEP_ISTEP >> 3] = { SIGTRAP, TRAP_TRACE }, /* Monitor */
69 [EXCEP_IBREAK >> 3] = { SIGTRAP, TRAP_HWBKPT }, /* Monitor */
70 [EXCEP_OBREAK >> 3] = { SIGTRAP, TRAP_HWBKPT }, /* Monitor */
71 [EXCEP_PRIVINS >> 3] = { SIGILL, ILL_PRVOPC },
72 [EXCEP_UNIMPINS >> 3] = { SIGILL, ILL_ILLOPC },
73 [EXCEP_UNIMPEXINS >> 3] = { SIGILL, ILL_ILLOPC },
74 [EXCEP_MEMERR >> 3] = { SIGSEGV, SEGV_ACCERR },
75 [EXCEP_MISALIGN >> 3] = { SIGBUS, BUS_ADRALN },
76 [EXCEP_BUSERROR >> 3] = { SIGBUS, BUS_ADRERR },
77 [EXCEP_ILLINSACC >> 3] = { SIGSEGV, SEGV_ACCERR },
78 [EXCEP_ILLDATACC >> 3] = { SIGSEGV, SEGV_ACCERR },
79 [EXCEP_IOINSACC >> 3] = { SIGSEGV, SEGV_ACCERR },
80 [EXCEP_PRIVINSACC >> 3] = { SIGSEGV, SEGV_ACCERR }, /* userspace */
81 [EXCEP_PRIVDATACC >> 3] = { SIGSEGV, SEGV_ACCERR }, /* userspace */
82 [EXCEP_DATINSACC >> 3] = { SIGSEGV, SEGV_ACCERR },
83 [EXCEP_DOUBLE_FAULT >> 3] = { SIGILL, ILL_BADSTK },
85 /* FPU exceptions */
86 [EXCEP_FPU_DISABLED >> 3] = { SIGILL, ILL_COPROC },
87 [EXCEP_FPU_UNIMPINS >> 3] = { SIGILL, ILL_COPROC },
88 [EXCEP_FPU_OPERATION >> 3] = { SIGFPE, FPE_INTDIV },
90 /* interrupts */
91 [EXCEP_WDT >> 3] = { SIGALRM, 0 },
92 [EXCEP_NMI >> 3] = { SIGQUIT, 0 },
93 [EXCEP_IRQ_LEVEL0 >> 3] = { SIGINT, 0 },
94 [EXCEP_IRQ_LEVEL1 >> 3] = { 0, 0 },
95 [EXCEP_IRQ_LEVEL2 >> 3] = { 0, 0 },
96 [EXCEP_IRQ_LEVEL3 >> 3] = { 0, 0 },
97 [EXCEP_IRQ_LEVEL4 >> 3] = { 0, 0 },
98 [EXCEP_IRQ_LEVEL5 >> 3] = { 0, 0 },
99 [EXCEP_IRQ_LEVEL6 >> 3] = { 0, 0 },
101 /* system calls */
102 [EXCEP_SYSCALL0 >> 3] = { 0, 0 },
103 [EXCEP_SYSCALL1 >> 3] = { SIGILL, ILL_ILLTRP },
104 [EXCEP_SYSCALL2 >> 3] = { SIGILL, ILL_ILLTRP },
105 [EXCEP_SYSCALL3 >> 3] = { SIGILL, ILL_ILLTRP },
106 [EXCEP_SYSCALL4 >> 3] = { SIGILL, ILL_ILLTRP },
107 [EXCEP_SYSCALL5 >> 3] = { SIGILL, ILL_ILLTRP },
108 [EXCEP_SYSCALL6 >> 3] = { SIGILL, ILL_ILLTRP },
109 [EXCEP_SYSCALL7 >> 3] = { SIGILL, ILL_ILLTRP },
110 [EXCEP_SYSCALL8 >> 3] = { SIGILL, ILL_ILLTRP },
111 [EXCEP_SYSCALL9 >> 3] = { SIGILL, ILL_ILLTRP },
112 [EXCEP_SYSCALL10 >> 3] = { SIGILL, ILL_ILLTRP },
113 [EXCEP_SYSCALL11 >> 3] = { SIGILL, ILL_ILLTRP },
114 [EXCEP_SYSCALL12 >> 3] = { SIGILL, ILL_ILLTRP },
115 [EXCEP_SYSCALL13 >> 3] = { SIGILL, ILL_ILLTRP },
116 [EXCEP_SYSCALL14 >> 3] = { SIGILL, ILL_ILLTRP },
117 [EXCEP_SYSCALL15 >> 3] = { SIGABRT, 0 },
121 * Handle kernel exceptions.
123 * See if there's a fixup handler we can force a jump to when an exception
124 * happens due to something kernel code did
126 int die_if_no_fixup(const char *str, struct pt_regs *regs,
127 enum exception_code code)
129 u8 opcode;
130 int signo, si_code;
132 if (user_mode(regs))
133 return 0;
135 peripheral_leds_display_exception(code);
137 signo = exception_to_signal_map[code >> 3].signo;
138 si_code = exception_to_signal_map[code >> 3].si_code;
140 switch (code) {
141 /* see if we can fixup the kernel accessing memory */
142 case EXCEP_ITLBMISS:
143 case EXCEP_DTLBMISS:
144 case EXCEP_IAERROR:
145 case EXCEP_DAERROR:
146 case EXCEP_MEMERR:
147 case EXCEP_MISALIGN:
148 case EXCEP_BUSERROR:
149 case EXCEP_ILLDATACC:
150 case EXCEP_IOINSACC:
151 case EXCEP_PRIVINSACC:
152 case EXCEP_PRIVDATACC:
153 case EXCEP_DATINSACC:
154 if (fixup_exception(regs))
155 return 1;
156 break;
158 case EXCEP_TRAP:
159 case EXCEP_UNIMPINS:
160 if (probe_kernel_read(&opcode, (u8 *)regs->pc, 1) < 0)
161 break;
162 if (opcode == 0xff) {
163 if (notify_die(DIE_BREAKPOINT, str, regs, code, 0, 0))
164 return 1;
165 if (at_debugger_breakpoint(regs))
166 regs->pc++;
167 signo = SIGTRAP;
168 si_code = TRAP_BRKPT;
170 break;
172 case EXCEP_SYSCALL1 ... EXCEP_SYSCALL14:
173 /* syscall return addr is _after_ the instruction */
174 regs->pc -= 2;
175 break;
177 case EXCEP_SYSCALL15:
178 if (report_bug(regs->pc, regs) == BUG_TRAP_TYPE_WARN)
179 return 1;
181 /* syscall return addr is _after_ the instruction */
182 regs->pc -= 2;
183 break;
185 default:
186 break;
189 if (debugger_intercept(code, signo, si_code, regs) == 0)
190 return 1;
192 if (notify_die(DIE_GPF, str, regs, code, 0, 0))
193 return 1;
195 /* make the process die as the last resort */
196 die(str, regs, code);
200 * General exception handler
202 asmlinkage void handle_exception(struct pt_regs *regs, u32 intcode)
204 siginfo_t info;
206 /* deal with kernel exceptions here */
207 if (die_if_no_fixup(NULL, regs, intcode))
208 return;
210 /* otherwise it's a userspace exception */
211 info.si_signo = exception_to_signal_map[intcode >> 3].signo;
212 info.si_code = exception_to_signal_map[intcode >> 3].si_code;
213 info.si_errno = 0;
214 info.si_addr = (void *) regs->pc;
215 force_sig_info(info.si_signo, &info, current);
219 * handle NMI
221 asmlinkage void nmi(struct pt_regs *regs, enum exception_code code)
223 /* see if gdbstub wants to deal with it */
224 if (debugger_intercept(code, SIGQUIT, 0, regs))
225 return;
227 printk(KERN_WARNING "--- Register Dump ---\n");
228 show_registers(regs);
229 printk(KERN_WARNING "---------------------\n");
233 * show a stack trace from the specified stack pointer
235 void show_trace(unsigned long *sp)
237 unsigned long bottom, stack, addr, fp, raslot;
239 printk(KERN_EMERG "\nCall Trace:\n");
241 //stack = (unsigned long)sp;
242 asm("mov sp,%0" : "=a"(stack));
243 asm("mov a3,%0" : "=r"(fp));
245 raslot = ULONG_MAX;
246 bottom = (stack + THREAD_SIZE) & ~(THREAD_SIZE - 1);
247 for (; stack < bottom; stack += sizeof(addr)) {
248 addr = *(unsigned long *)stack;
249 if (stack == fp) {
250 if (addr > stack && addr < bottom) {
251 fp = addr;
252 raslot = stack + sizeof(addr);
253 continue;
255 fp = 0;
256 raslot = ULONG_MAX;
259 if (__kernel_text_address(addr)) {
260 printk(" [<%08lx>]", addr);
261 if (stack >= raslot)
262 raslot = ULONG_MAX;
263 else
264 printk(" ?");
265 print_symbol(" %s", addr);
266 printk("\n");
270 printk("\n");
274 * show the raw stack from the specified stack pointer
276 void show_stack(struct task_struct *task, unsigned long *sp)
278 unsigned long *stack;
279 int i;
281 if (!sp)
282 sp = (unsigned long *) &sp;
284 stack = sp;
285 printk(KERN_EMERG "Stack:");
286 for (i = 0; i < kstack_depth_to_print; i++) {
287 if (((long) stack & (THREAD_SIZE - 1)) == 0)
288 break;
289 if ((i % 8) == 0)
290 printk(KERN_EMERG " ");
291 printk("%08lx ", *stack++);
294 show_trace(sp);
298 * dump the register file in the specified exception frame
300 void show_registers_only(struct pt_regs *regs)
302 unsigned long ssp;
304 ssp = (unsigned long) regs + sizeof(*regs);
306 printk(KERN_EMERG "PC: %08lx EPSW: %08lx SSP: %08lx mode: %s\n",
307 regs->pc, regs->epsw, ssp, user_mode(regs) ? "User" : "Super");
308 printk(KERN_EMERG "d0: %08lx d1: %08lx d2: %08lx d3: %08lx\n",
309 regs->d0, regs->d1, regs->d2, regs->d3);
310 printk(KERN_EMERG "a0: %08lx a1: %08lx a2: %08lx a3: %08lx\n",
311 regs->a0, regs->a1, regs->a2, regs->a3);
312 printk(KERN_EMERG "e0: %08lx e1: %08lx e2: %08lx e3: %08lx\n",
313 regs->e0, regs->e1, regs->e2, regs->e3);
314 printk(KERN_EMERG "e4: %08lx e5: %08lx e6: %08lx e7: %08lx\n",
315 regs->e4, regs->e5, regs->e6, regs->e7);
316 printk(KERN_EMERG "lar: %08lx lir: %08lx mdr: %08lx usp: %08lx\n",
317 regs->lar, regs->lir, regs->mdr, regs->sp);
318 printk(KERN_EMERG "cvf: %08lx crl: %08lx crh: %08lx drq: %08lx\n",
319 regs->mcvf, regs->mcrl, regs->mcrh, regs->mdrq);
320 printk(KERN_EMERG "threadinfo=%p task=%p)\n",
321 current_thread_info(), current);
323 if ((unsigned long) current >= PAGE_OFFSET &&
324 (unsigned long) current < (unsigned long)high_memory)
325 printk(KERN_EMERG "Process %s (pid: %d)\n",
326 current->comm, current->pid);
328 #ifdef CONFIG_SMP
329 printk(KERN_EMERG "CPUID: %08x\n", CPUID);
330 #endif
331 printk(KERN_EMERG "CPUP: %04hx\n", CPUP);
332 printk(KERN_EMERG "TBR: %08x\n", TBR);
333 printk(KERN_EMERG "DEAR: %08x\n", DEAR);
334 printk(KERN_EMERG "sISR: %08x\n", sISR);
335 printk(KERN_EMERG "NMICR: %04hx\n", NMICR);
336 printk(KERN_EMERG "BCBERR: %08x\n", BCBERR);
337 printk(KERN_EMERG "BCBEAR: %08x\n", BCBEAR);
338 printk(KERN_EMERG "MMUFCR: %08x\n", MMUFCR);
339 printk(KERN_EMERG "IPTEU : %08x IPTEL2: %08x\n", IPTEU, IPTEL2);
340 printk(KERN_EMERG "DPTEU: %08x DPTEL2: %08x\n", DPTEU, DPTEL2);
344 * dump the registers and the stack
346 void show_registers(struct pt_regs *regs)
348 unsigned long sp;
349 int i;
351 show_registers_only(regs);
353 if (!user_mode(regs))
354 sp = (unsigned long) regs + sizeof(*regs);
355 else
356 sp = regs->sp;
358 /* when in-kernel, we also print out the stack and code at the
359 * time of the fault..
361 if (!user_mode(regs)) {
362 printk(KERN_EMERG "\n");
363 show_stack(current, (unsigned long *) sp);
365 #if 0
366 printk(KERN_EMERG "\nCode: ");
367 if (regs->pc < PAGE_OFFSET)
368 goto bad;
370 for (i = 0; i < 20; i++) {
371 unsigned char c;
372 if (__get_user(c, &((unsigned char *) regs->pc)[i]))
373 goto bad;
374 printk("%02x ", c);
376 #else
377 i = 0;
378 #endif
381 printk("\n");
382 return;
384 #if 0
385 bad:
386 printk(KERN_EMERG " Bad PC value.");
387 break;
388 #endif
394 void show_trace_task(struct task_struct *tsk)
396 unsigned long sp = tsk->thread.sp;
398 /* User space on another CPU? */
399 if ((sp ^ (unsigned long) tsk) & (PAGE_MASK << 1))
400 return;
402 show_trace((unsigned long *) sp);
406 * note the untimely death of part of the kernel
408 void die(const char *str, struct pt_regs *regs, enum exception_code code)
410 console_verbose();
411 spin_lock_irq(&die_lock);
412 printk(KERN_EMERG "\n%s: %04x\n",
413 str, code & 0xffff);
414 show_registers(regs);
416 if (regs->pc >= 0x02000000 && regs->pc < 0x04000000 &&
417 (regs->epsw & (EPSW_IM | EPSW_IE)) != (EPSW_IM | EPSW_IE)) {
418 printk(KERN_EMERG "Exception in usermode interrupt handler\n");
419 printk(KERN_EMERG "\nPlease connect to kernel debugger !!\n");
420 asm volatile ("0: bra 0b");
423 spin_unlock_irq(&die_lock);
424 do_exit(SIGSEGV);
428 * display the register file when the stack pointer gets clobbered
430 asmlinkage void do_double_fault(struct pt_regs *regs)
432 struct task_struct *tsk = current;
434 strcpy(tsk->comm, "emergency tsk");
435 tsk->pid = 0;
436 console_verbose();
437 printk(KERN_EMERG "--- double fault ---\n");
438 show_registers(regs);
442 * asynchronous bus error (external, usually I/O DMA)
444 asmlinkage void io_bus_error(u32 bcberr, u32 bcbear, struct pt_regs *regs)
446 console_verbose();
448 printk(KERN_EMERG "Asynchronous I/O Bus Error\n");
449 printk(KERN_EMERG "==========================\n");
451 if (bcberr & BCBERR_BEME)
452 printk(KERN_EMERG "- Multiple recorded errors\n");
454 printk(KERN_EMERG "- Faulting Buses:%s%s%s\n",
455 bcberr & BCBERR_BEMR_CI ? " CPU-Ins-Fetch" : "",
456 bcberr & BCBERR_BEMR_CD ? " CPU-Data" : "",
457 bcberr & BCBERR_BEMR_DMA ? " DMA" : "");
459 printk(KERN_EMERG "- %s %s access made to %s at address %08x\n",
460 bcberr & BCBERR_BEBST ? "Burst" : "Single",
461 bcberr & BCBERR_BERW ? "Read" : "Write",
462 bcberr & BCBERR_BESB_MON ? "Monitor Space" :
463 bcberr & BCBERR_BESB_IO ? "Internal CPU I/O Space" :
464 bcberr & BCBERR_BESB_EX ? "External I/O Bus" :
465 bcberr & BCBERR_BESB_OPEX ? "External Memory Bus" :
466 "On Chip Memory",
467 bcbear
470 printk(KERN_EMERG "- Detected by the %s\n",
471 bcberr&BCBERR_BESD ? "Bus Control Unit" : "Slave Bus");
473 #ifdef CONFIG_PCI
474 #define BRIDGEREGB(X) (*(volatile __u8 *)(0xBE040000 + (X)))
475 #define BRIDGEREGW(X) (*(volatile __u16 *)(0xBE040000 + (X)))
476 #define BRIDGEREGL(X) (*(volatile __u32 *)(0xBE040000 + (X)))
478 printk(KERN_EMERG "- PCI Memory Paging Reg: %08x\n",
479 *(volatile __u32 *) (0xBFFFFFF4));
480 printk(KERN_EMERG "- PCI Bridge Base Address 0: %08x\n",
481 BRIDGEREGL(PCI_BASE_ADDRESS_0));
482 printk(KERN_EMERG "- PCI Bridge AMPCI Base Address: %08x\n",
483 BRIDGEREGL(0x48));
484 printk(KERN_EMERG "- PCI Bridge Command: %04hx\n",
485 BRIDGEREGW(PCI_COMMAND));
486 printk(KERN_EMERG "- PCI Bridge Status: %04hx\n",
487 BRIDGEREGW(PCI_STATUS));
488 printk(KERN_EMERG "- PCI Bridge Int Status: %08hx\n",
489 BRIDGEREGL(0x4c));
490 #endif
492 printk(KERN_EMERG "\n");
493 show_registers(regs);
495 panic("Halted due to asynchronous I/O Bus Error\n");
499 * handle an exception for which a handler has not yet been installed
501 asmlinkage void uninitialised_exception(struct pt_regs *regs,
502 enum exception_code code)
505 /* see if gdbstub wants to deal with it */
506 if (debugger_intercept(code, SIGSYS, 0, regs) == 0)
507 return;
509 peripheral_leds_display_exception(code);
510 printk(KERN_EMERG "Uninitialised Exception 0x%04x\n", code & 0xFFFF);
511 show_registers(regs);
513 for (;;)
514 continue;
518 * set an interrupt stub to jump to a handler
519 * ! NOTE: this does *not* flush the caches
521 void __init __set_intr_stub(enum exception_code code, void *handler)
523 unsigned long addr;
524 u8 *vector = (u8 *)(CONFIG_INTERRUPT_VECTOR_BASE + code);
526 addr = (unsigned long) handler - (unsigned long) vector;
527 vector[0] = 0xdc; /* JMP handler */
528 vector[1] = addr;
529 vector[2] = addr >> 8;
530 vector[3] = addr >> 16;
531 vector[4] = addr >> 24;
532 vector[5] = 0xcb;
533 vector[6] = 0xcb;
534 vector[7] = 0xcb;
538 * set an interrupt stub to jump to a handler
540 void __init set_intr_stub(enum exception_code code, void *handler)
542 unsigned long addr;
543 u8 *vector = (u8 *)(CONFIG_INTERRUPT_VECTOR_BASE + code);
544 unsigned long flags;
546 addr = (unsigned long) handler - (unsigned long) vector;
548 flags = arch_local_cli_save();
550 vector[0] = 0xdc; /* JMP handler */
551 vector[1] = addr;
552 vector[2] = addr >> 8;
553 vector[3] = addr >> 16;
554 vector[4] = addr >> 24;
555 vector[5] = 0xcb;
556 vector[6] = 0xcb;
557 vector[7] = 0xcb;
559 arch_local_irq_restore(flags);
561 #ifndef CONFIG_MN10300_CACHE_SNOOP
562 mn10300_dcache_flush_inv();
563 mn10300_icache_inv();
564 #endif
568 * initialise the exception table
570 void __init trap_init(void)
572 set_excp_vector(EXCEP_TRAP, handle_exception);
573 set_excp_vector(EXCEP_ISTEP, handle_exception);
574 set_excp_vector(EXCEP_IBREAK, handle_exception);
575 set_excp_vector(EXCEP_OBREAK, handle_exception);
577 set_excp_vector(EXCEP_PRIVINS, handle_exception);
578 set_excp_vector(EXCEP_UNIMPINS, handle_exception);
579 set_excp_vector(EXCEP_UNIMPEXINS, handle_exception);
580 set_excp_vector(EXCEP_MEMERR, handle_exception);
581 set_excp_vector(EXCEP_MISALIGN, misalignment);
582 set_excp_vector(EXCEP_BUSERROR, handle_exception);
583 set_excp_vector(EXCEP_ILLINSACC, handle_exception);
584 set_excp_vector(EXCEP_ILLDATACC, handle_exception);
585 set_excp_vector(EXCEP_IOINSACC, handle_exception);
586 set_excp_vector(EXCEP_PRIVINSACC, handle_exception);
587 set_excp_vector(EXCEP_PRIVDATACC, handle_exception);
588 set_excp_vector(EXCEP_DATINSACC, handle_exception);
589 set_excp_vector(EXCEP_FPU_UNIMPINS, handle_exception);
590 set_excp_vector(EXCEP_FPU_OPERATION, fpu_exception);
592 set_excp_vector(EXCEP_NMI, nmi);
594 set_excp_vector(EXCEP_SYSCALL1, handle_exception);
595 set_excp_vector(EXCEP_SYSCALL2, handle_exception);
596 set_excp_vector(EXCEP_SYSCALL3, handle_exception);
597 set_excp_vector(EXCEP_SYSCALL4, handle_exception);
598 set_excp_vector(EXCEP_SYSCALL5, handle_exception);
599 set_excp_vector(EXCEP_SYSCALL6, handle_exception);
600 set_excp_vector(EXCEP_SYSCALL7, handle_exception);
601 set_excp_vector(EXCEP_SYSCALL8, handle_exception);
602 set_excp_vector(EXCEP_SYSCALL9, handle_exception);
603 set_excp_vector(EXCEP_SYSCALL10, handle_exception);
604 set_excp_vector(EXCEP_SYSCALL11, handle_exception);
605 set_excp_vector(EXCEP_SYSCALL12, handle_exception);
606 set_excp_vector(EXCEP_SYSCALL13, handle_exception);
607 set_excp_vector(EXCEP_SYSCALL14, handle_exception);
608 set_excp_vector(EXCEP_SYSCALL15, handle_exception);
612 * determine if a program counter value is a valid bug address
614 int is_valid_bugaddr(unsigned long pc)
616 return pc >= PAGE_OFFSET;