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[PATCH] x86_64: Sparse warnings fix.
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / arch / x86_64 / kernel / traps.c
CommitLineData
1da177e4
LT		 1/*
2 * linux/arch/x86-64/traps.c
3 *
4 * Copyright (C) 1991, 1992 Linus Torvalds
5 * Copyright (C) 2000, 2001, 2002 Andi Kleen, SuSE Labs
6 *
7 * Pentium III FXSR, SSE support
8 * Gareth Hughes <gareth@valinux.com>, May 2000
9 *
10 * $Id: traps.c,v 1.36 2002/03/24 11:09:10 ak Exp $
11 */
12
13/*
14 * 'Traps.c' handles hardware traps and faults after we have saved some
15 * state in 'entry.S'.
16 */
17#include <linux/config.h>
18#include <linux/sched.h>
19#include <linux/kernel.h>
20#include <linux/string.h>
21#include <linux/errno.h>
22#include <linux/ptrace.h>
23#include <linux/timer.h>
24#include <linux/mm.h>
25#include <linux/init.h>
26#include <linux/delay.h>
27#include <linux/spinlock.h>
28#include <linux/interrupt.h>
29#include <linux/module.h>
30#include <linux/moduleparam.h>
35faa714 31#include <linux/nmi.h>
0f2fbdcb 32#include <linux/kprobes.h>
1da177e4
LT		 33
34#include <asm/system.h>
35#include <asm/uaccess.h>
36#include <asm/io.h>
37#include <asm/atomic.h>
38#include <asm/debugreg.h>
39#include <asm/desc.h>
40#include <asm/i387.h>
41#include <asm/kdebug.h>
42#include <asm/processor.h>
43
44#include <asm/smp.h>
45#include <asm/pgalloc.h>
46#include <asm/pda.h>
47#include <asm/proto.h>
48#include <asm/nmi.h>
49
1da177e4
LT		 50extern struct gate_struct idt_table[256];
51
52asmlinkage void divide_error(void);
53asmlinkage void debug(void);
54asmlinkage void nmi(void);
55asmlinkage void int3(void);
56asmlinkage void overflow(void);
57asmlinkage void bounds(void);
58asmlinkage void invalid_op(void);
59asmlinkage void device_not_available(void);
60asmlinkage void double_fault(void);
61asmlinkage void coprocessor_segment_overrun(void);
62asmlinkage void invalid_TSS(void);
63asmlinkage void segment_not_present(void);
64asmlinkage void stack_segment(void);
65asmlinkage void general_protection(void);
66asmlinkage void page_fault(void);
67asmlinkage void coprocessor_error(void);
68asmlinkage void simd_coprocessor_error(void);
69asmlinkage void reserved(void);
70asmlinkage void alignment_check(void);
71asmlinkage void machine_check(void);
72asmlinkage void spurious_interrupt_bug(void);
1da177e4
LT		 73
74struct notifier_block *die_chain;
75static DEFINE_SPINLOCK(die_notifier_lock);
76
77int register_die_notifier(struct notifier_block *nb)
78{
79 int err = 0;
80 unsigned long flags;
81 spin_lock_irqsave(&die_notifier_lock, flags);
82 err = notifier_chain_register(&die_chain, nb);
83 spin_unlock_irqrestore(&die_notifier_lock, flags);
84 return err;
85}
86
87static inline void conditional_sti(struct pt_regs *regs)
88{
89 if (regs->eflags & X86_EFLAGS_IF)
90 local_irq_enable();
91}
92
93static int kstack_depth_to_print = 10;
94
95#ifdef CONFIG_KALLSYMS
96#include <linux/kallsyms.h>
97int printk_address(unsigned long address)
98{
99 unsigned long offset = 0, symsize;
100 const char *symname;
101 char *modname;
102 char *delim = ":";
103 char namebuf[128];
104
105 symname = kallsyms_lookup(address, &symsize, &offset, &modname, namebuf);
106 if (!symname)
107 return printk("[<%016lx>]", address);
108 if (!modname)
109 modname = delim = "";
110 return printk("<%016lx>{%s%s%s%s%+ld}",
111 address,delim,modname,delim,symname,offset);
112}
113#else
114int printk_address(unsigned long address)
115{
116 return printk("[<%016lx>]", address);
117}
118#endif
119
0a658002
AK		 120static unsigned long *in_exception_stack(unsigned cpu, unsigned long stack,
121 unsigned *usedp, const char **idp)
122{
b556b35e 123 static char ids[][8] = {
0a658002
AK		 124 [DEBUG_STACK - 1] = "#DB",
125 [NMI_STACK - 1] = "NMI",
126 [DOUBLEFAULT_STACK - 1] = "#DF",
127 [STACKFAULT_STACK - 1] = "#SS",
128 [MCE_STACK - 1] = "#MC",
b556b35e
JB		 129#if DEBUG_STKSZ > EXCEPTION_STKSZ
130 [N_EXCEPTION_STACKS ... N_EXCEPTION_STACKS + DEBUG_STKSZ / EXCEPTION_STKSZ - 2] = "#DB[?]"
131#endif
0a658002
AK		 132 };
133 unsigned k;
1da177e4 134
0a658002
AK		 135 for (k = 0; k < N_EXCEPTION_STACKS; k++) {
136 unsigned long end;
137
b556b35e
JB		 138 switch (k + 1) {
139#if DEBUG_STKSZ > EXCEPTION_STKSZ
140 case DEBUG_STACK:
df79efde 141 end = cpu_pda(cpu)->debugstack + DEBUG_STKSZ;
b556b35e
JB		 142 break;
143#endif
144 default:
145 end = per_cpu(init_tss, cpu).ist[k];
146 break;
147 }
0a658002
AK		 148 if (stack >= end)
149 continue;
150 if (stack >= end - EXCEPTION_STKSZ) {
151 if (*usedp & (1U << k))
152 break;
153 *usedp |= 1U << k;
154 *idp = ids[k];
155 return (unsigned long *)end;
156 }
b556b35e
JB		 157#if DEBUG_STKSZ > EXCEPTION_STKSZ
158 if (k == DEBUG_STACK - 1 && stack >= end - DEBUG_STKSZ) {
159 unsigned j = N_EXCEPTION_STACKS - 1;
160
161 do {
162 ++j;
163 end -= EXCEPTION_STKSZ;
164 ids[j][4] = '1' + (j - N_EXCEPTION_STACKS);
165 } while (stack < end - EXCEPTION_STKSZ);
166 if (*usedp & (1U << j))
167 break;
168 *usedp |= 1U << j;
169 *idp = ids[j];
170 return (unsigned long *)end;
171 }
172#endif
1da177e4
LT		 173 }
174 return NULL;
0a658002 175}
1da177e4
LT		 176
177/*
178 * x86-64 can have upto three kernel stacks:
179 * process stack
180 * interrupt stack
0a658002 181 * severe exception (double fault, nmi, stack fault, debug, mce) hardware stack
1da177e4
LT		 182 */
183
184void show_trace(unsigned long *stack)
185{
186 unsigned long addr;
0a658002 187 const unsigned cpu = safe_smp_processor_id();
df79efde 188 unsigned long *irqstack_end = (unsigned long *)cpu_pda(cpu)->irqstackptr;
1da177e4 189 int i;
0a658002 190 unsigned used = 0;
1da177e4
LT		 191
192 printk("\nCall Trace:");
0a658002
AK		 193
194#define HANDLE_STACK(cond) \
195 do while (cond) { \
196 addr = *stack++; \
197 if (kernel_text_address(addr)) { \
198 /* \
199 * If the address is either in the text segment of the \
200 * kernel, or in the region which contains vmalloc'ed \
201 * memory, it *may* be the address of a calling \
202 * routine; if so, print it so that someone tracing \
203 * down the cause of the crash will be able to figure \
204 * out the call path that was taken. \
205 */ \
206 i += printk_address(addr); \
207 if (i > 50) { \
208 printk("\n "); \
209 i = 0; \
210 } \
211 else \
212 i += printk(" "); \
213 } \
214 } while (0)
215
216 for(i = 0; ; ) {
217 const char *id;
218 unsigned long *estack_end;
219 estack_end = in_exception_stack(cpu, (unsigned long)stack,
220 &used, &id);
221
222 if (estack_end) {
223 i += printk(" <%s> ", id);
224 HANDLE_STACK (stack < estack_end);
225 i += printk(" <EOE> ");
226 stack = (unsigned long *) estack_end[-2];
227 continue;
1da177e4 228 }
0a658002
AK		 229 if (irqstack_end) {
230 unsigned long *irqstack;
231 irqstack = irqstack_end -
232 (IRQSTACKSIZE - 64) / sizeof(*irqstack);
233
234 if (stack >= irqstack && stack < irqstack_end) {
235 i += printk(" <IRQ> ");
236 HANDLE_STACK (stack < irqstack_end);
237 stack = (unsigned long *) (irqstack_end[-1]);
238 irqstack_end = NULL;
239 i += printk(" <EOI> ");
240 continue;
1da177e4 241 }
1da177e4 242 }
0a658002 243 break;
1da177e4 244 }
0a658002
AK		 245
246 HANDLE_STACK (((long) stack & (THREAD_SIZE-1)) != 0);
247#undef HANDLE_STACK
1da177e4
LT		 248 printk("\n");
249}
250
251void show_stack(struct task_struct *tsk, unsigned long * rsp)
252{
253 unsigned long *stack;
254 int i;
255 const int cpu = safe_smp_processor_id();
df79efde
RT		 256 unsigned long *irqstack_end = (unsigned long *) (cpu_pda(cpu)->irqstackptr);
257 unsigned long *irqstack = (unsigned long *) (cpu_pda(cpu)->irqstackptr - IRQSTACKSIZE);
1da177e4
LT		 258
259 // debugging aid: "show_stack(NULL, NULL);" prints the
260 // back trace for this cpu.
261
262 if (rsp == NULL) {
263 if (tsk)
264 rsp = (unsigned long *)tsk->thread.rsp;
265 else
266 rsp = (unsigned long *)&rsp;
267 }
268
269 stack = rsp;
270 for(i=0; i < kstack_depth_to_print; i++) {
271 if (stack >= irqstack && stack <= irqstack_end) {
272 if (stack == irqstack_end) {
273 stack = (unsigned long *) (irqstack_end[-1]);
274 printk(" <EOI> ");
275 }
276 } else {
277 if (((long) stack & (THREAD_SIZE-1)) == 0)
278 break;
279 }
280 if (i && ((i % 4) == 0))
281 printk("\n ");
282 printk("%016lx ", *stack++);
35faa714 283 touch_nmi_watchdog();
1da177e4
LT		 284 }
285 show_trace((unsigned long *)rsp);
286}
287
288/*
289 * The architecture-independent dump_stack generator
290 */
291void dump_stack(void)
292{
293 unsigned long dummy;
294 show_trace(&dummy);
295}
296
297EXPORT_SYMBOL(dump_stack);
298
299void show_registers(struct pt_regs *regs)
300{
301 int i;
76381fee 302 int in_kernel = !user_mode(regs);
1da177e4
LT		 303 unsigned long rsp;
304 const int cpu = safe_smp_processor_id();
df79efde 305 struct task_struct *cur = cpu_pda(cpu)->pcurrent;
1da177e4
LT		 306
307 rsp = regs->rsp;
308
309 printk("CPU %d ", cpu);
310 __show_regs(regs);
311 printk("Process %s (pid: %d, threadinfo %p, task %p)\n",
312 cur->comm, cur->pid, cur->thread_info, cur);
313
314 /*
315 * When in-kernel, we also print out the stack and code at the
316 * time of the fault..
317 */
318 if (in_kernel) {
319
320 printk("Stack: ");
321 show_stack(NULL, (unsigned long*)rsp);
322
323 printk("\nCode: ");
324 if(regs->rip < PAGE_OFFSET)
325 goto bad;
326
327 for(i=0;i<20;i++)
328 {
329 unsigned char c;
330 if(__get_user(c, &((unsigned char*)regs->rip)[i])) {
331bad:
332 printk(" Bad RIP value.");
333 break;
334 }
335 printk("%02x ", c);
336 }
337 }
338 printk("\n");
339}
340
341void handle_BUG(struct pt_regs *regs)
342{
343 struct bug_frame f;
344 char tmp;
345
76381fee 346 if (user_mode(regs))
1da177e4
LT		 347 return;
348 if (__copy_from_user(&f, (struct bug_frame *) regs->rip,
349 sizeof(struct bug_frame)))
350 return;
049cdefe 351 if (f.filename >= 0 ||
1da177e4
LT		 352 f.ud2[0] != 0x0f || f.ud2[1] != 0x0b)
353 return;
049cdefe
JB		 354 if (__get_user(tmp, (char *)(long)f.filename))
355 f.filename = (int)(long)"unmapped filename";
1da177e4 356 printk("----------- [cut here ] --------- [please bite here ] ---------\n");
049cdefe 357 printk(KERN_ALERT "Kernel BUG at %.50s:%d\n", (char *)(long)f.filename, f.line);
1da177e4
LT		 358}
359
4f60fdf6 360#ifdef CONFIG_BUG
1da177e4
LT		 361void out_of_line_bug(void)
362{
363 BUG();
364}
4f60fdf6 365#endif
1da177e4
LT		 366
367static DEFINE_SPINLOCK(die_lock);
368static int die_owner = -1;
369
1209140c 370unsigned long oops_begin(void)
1da177e4 371{
1209140c
JB		 372 int cpu = safe_smp_processor_id();
373 unsigned long flags;
374
375 /* racy, but better than risking deadlock. */
376 local_irq_save(flags);
1da177e4
LT		 377 if (!spin_trylock(&die_lock)) {
378 if (cpu == die_owner)
379 /* nested oops. should stop eventually */;
380 else
1209140c 381 spin_lock(&die_lock);
1da177e4 382 }
1209140c 383 die_owner = cpu;
1da177e4 384 console_verbose();
1209140c
JB		 385 bust_spinlocks(1);
386 return flags;
1da177e4
LT		 387}
388
1209140c 389void oops_end(unsigned long flags)
1da177e4
LT		 390{
391 die_owner = -1;
1209140c
JB		 392 bust_spinlocks(0);
393 spin_unlock_irqrestore(&die_lock, flags);
1da177e4 394 if (panic_on_oops)
1209140c
JB		 395 panic("Oops");
396}
1da177e4
LT		 397
398void __die(const char * str, struct pt_regs * regs, long err)
399{
400 static int die_counter;
401 printk(KERN_EMERG "%s: %04lx [%u] ", str, err & 0xffff,++die_counter);
402#ifdef CONFIG_PREEMPT
403 printk("PREEMPT ");
404#endif
405#ifdef CONFIG_SMP
406 printk("SMP ");
407#endif
408#ifdef CONFIG_DEBUG_PAGEALLOC
409 printk("DEBUG_PAGEALLOC");
410#endif
411 printk("\n");
6e3f3617 412 notify_die(DIE_OOPS, str, regs, err, current->thread.trap_no, SIGSEGV);
1da177e4
LT		 413 show_registers(regs);
414 /* Executive summary in case the oops scrolled away */
415 printk(KERN_ALERT "RIP ");
416 printk_address(regs->rip);
417 printk(" RSP <%016lx>\n", regs->rsp);
418}
419
420void die(const char * str, struct pt_regs * regs, long err)
421{
1209140c
JB		 422 unsigned long flags = oops_begin();
423
1da177e4
LT		 424 handle_BUG(regs);
425 __die(str, regs, err);
1209140c 426 oops_end(flags);
1da177e4
LT		 427 do_exit(SIGSEGV);
428}
1da177e4
LT		 429
430void die_nmi(char *str, struct pt_regs *regs)
431{
1209140c
JB		 432 unsigned long flags = oops_begin();
433
1da177e4
LT		 434 /*
435 * We are in trouble anyway, lets at least try
436 * to get a message out.
437 */
438 printk(str, safe_smp_processor_id());
439 show_registers(regs);
440 if (panic_on_timeout || panic_on_oops)
441 panic("nmi watchdog");
442 printk("console shuts up ...\n");
1209140c 443 oops_end(flags);
1da177e4
LT		 444 do_exit(SIGSEGV);
445}
446
0f2fbdcb
PP		 447static void __kprobes do_trap(int trapnr, int signr, char *str,
448 struct pt_regs * regs, long error_code,
449 siginfo_t *info)
1da177e4 450{
6e3f3617
JB		 451 struct task_struct *tsk = current;
452
1da177e4
LT		 453 conditional_sti(regs);
454
6e3f3617
JB		 455 tsk->thread.error_code = error_code;
456 tsk->thread.trap_no = trapnr;
1da177e4 457
6e3f3617 458 if (user_mode(regs)) {
1da177e4
LT		 459 if (exception_trace && unhandled_signal(tsk, signr))
460 printk(KERN_INFO
461 "%s[%d] trap %s rip:%lx rsp:%lx error:%lx\n",
462 tsk->comm, tsk->pid, str,
463 regs->rip,regs->rsp,error_code);
464
1da177e4
LT		 465 if (info)
466 force_sig_info(signr, info, tsk);
467 else
468 force_sig(signr, tsk);
469 return;
470 }
471
472
473 /* kernel trap */
474 {
475 const struct exception_table_entry *fixup;
476 fixup = search_exception_tables(regs->rip);
477 if (fixup) {
478 regs->rip = fixup->fixup;
479 } else
480 die(str, regs, error_code);
481 return;
482 }
483}
484
485#define DO_ERROR(trapnr, signr, str, name) \
486asmlinkage void do_##name(struct pt_regs * regs, long error_code) \
487{ \
488 if (notify_die(DIE_TRAP, str, regs, error_code, trapnr, signr) \
489 == NOTIFY_STOP) \
490 return; \
491 do_trap(trapnr, signr, str, regs, error_code, NULL); \
492}
493
494#define DO_ERROR_INFO(trapnr, signr, str, name, sicode, siaddr) \
495asmlinkage void do_##name(struct pt_regs * regs, long error_code) \
496{ \
497 siginfo_t info; \
498 info.si_signo = signr; \
499 info.si_errno = 0; \
500 info.si_code = sicode; \
501 info.si_addr = (void __user *)siaddr; \
502 if (notify_die(DIE_TRAP, str, regs, error_code, trapnr, signr) \
503 == NOTIFY_STOP) \
504 return; \
505 do_trap(trapnr, signr, str, regs, error_code, &info); \
506}
507
508DO_ERROR_INFO( 0, SIGFPE, "divide error", divide_error, FPE_INTDIV, regs->rip)
509DO_ERROR( 4, SIGSEGV, "overflow", overflow)
510DO_ERROR( 5, SIGSEGV, "bounds", bounds)
511DO_ERROR_INFO( 6, SIGILL, "invalid operand", invalid_op, ILL_ILLOPN, regs->rip)
512DO_ERROR( 7, SIGSEGV, "device not available", device_not_available)
513DO_ERROR( 9, SIGFPE, "coprocessor segment overrun", coprocessor_segment_overrun)
514DO_ERROR(10, SIGSEGV, "invalid TSS", invalid_TSS)
515DO_ERROR(11, SIGBUS, "segment not present", segment_not_present)
516DO_ERROR_INFO(17, SIGBUS, "alignment check", alignment_check, BUS_ADRALN, 0)
517DO_ERROR(18, SIGSEGV, "reserved", reserved)
6fefb0d1 518DO_ERROR(12, SIGBUS, "stack segment", stack_segment)
eca37c18
JB		 519
520asmlinkage void do_double_fault(struct pt_regs * regs, long error_code)
521{
522 static const char str[] = "double fault";
523 struct task_struct *tsk = current;
524
525 /* Return not checked because double check cannot be ignored */
526 notify_die(DIE_TRAP, str, regs, error_code, 8, SIGSEGV);
527
528 tsk->thread.error_code = error_code;
529 tsk->thread.trap_no = 8;
530
531 /* This is always a kernel trap and never fixable (and thus must
532 never return). */
533 for (;;)
534 die(str, regs, error_code);
535}
1da177e4 536
0f2fbdcb
PP		 537asmlinkage void __kprobes do_general_protection(struct pt_regs * regs,
538 long error_code)
1da177e4 539{
6e3f3617
JB		 540 struct task_struct *tsk = current;
541
1da177e4
LT		 542 conditional_sti(regs);
543
6e3f3617
JB		 544 tsk->thread.error_code = error_code;
545 tsk->thread.trap_no = 13;
1da177e4 546
6e3f3617 547 if (user_mode(regs)) {
1da177e4
LT		 548 if (exception_trace && unhandled_signal(tsk, SIGSEGV))
549 printk(KERN_INFO
550 "%s[%d] general protection rip:%lx rsp:%lx error:%lx\n",
551 tsk->comm, tsk->pid,
552 regs->rip,regs->rsp,error_code);
553
1da177e4
LT		 554 force_sig(SIGSEGV, tsk);
555 return;
556 }
557
558 /* kernel gp */
559 {
560 const struct exception_table_entry *fixup;
561 fixup = search_exception_tables(regs->rip);
562 if (fixup) {
563 regs->rip = fixup->fixup;
564 return;
565 }
566 if (notify_die(DIE_GPF, "general protection fault", regs,
567 error_code, 13, SIGSEGV) == NOTIFY_STOP)
568 return;
569 die("general protection fault", regs, error_code);
570 }
571}
572
573static void mem_parity_error(unsigned char reason, struct pt_regs * regs)
574{
575 printk("Uhhuh. NMI received. Dazed and confused, but trying to continue\n");
576 printk("You probably have a hardware problem with your RAM chips\n");
577
578 /* Clear and disable the memory parity error line. */
579 reason = (reason & 0xf) | 4;
580 outb(reason, 0x61);
581}
582
583static void io_check_error(unsigned char reason, struct pt_regs * regs)
584{
585 printk("NMI: IOCK error (debug interrupt?)\n");
586 show_registers(regs);
587
588 /* Re-enable the IOCK line, wait for a few seconds */
589 reason = (reason & 0xf) | 8;
590 outb(reason, 0x61);
591 mdelay(2000);
592 reason &= ~8;
593 outb(reason, 0x61);
594}
595
596static void unknown_nmi_error(unsigned char reason, struct pt_regs * regs)
597{ printk("Uhhuh. NMI received for unknown reason %02x.\n", reason);
598 printk("Dazed and confused, but trying to continue\n");
599 printk("Do you have a strange power saving mode enabled?\n");
600}
601
6fefb0d1
AK		 602/* Runs on IST stack. This code must keep interrupts off all the time.
603 Nested NMIs are prevented by the CPU. */
1da177e4
LT		 604asmlinkage void default_do_nmi(struct pt_regs *regs)
605{
606 unsigned char reason = 0;
76e4f660
AR		 607 int cpu;
608
609 cpu = smp_processor_id();
1da177e4
LT		 610
611 /* Only the BSP gets external NMIs from the system. */
76e4f660 612 if (!cpu)
1da177e4
LT		 613 reason = get_nmi_reason();
614
615 if (!(reason & 0xc0)) {
6e3f3617 616 if (notify_die(DIE_NMI_IPI, "nmi_ipi", regs, reason, 2, SIGINT)
1da177e4
LT		 617 == NOTIFY_STOP)
618 return;
619#ifdef CONFIG_X86_LOCAL_APIC
620 /*
621 * Ok, so this is none of the documented NMI sources,
622 * so it must be the NMI watchdog.
623 */
624 if (nmi_watchdog > 0) {
625 nmi_watchdog_tick(regs,reason);
626 return;
627 }
628#endif
629 unknown_nmi_error(reason, regs);
630 return;
631 }
6e3f3617 632 if (notify_die(DIE_NMI, "nmi", regs, reason, 2, SIGINT) == NOTIFY_STOP)
1da177e4
LT		 633 return;
634
635 /* AK: following checks seem to be broken on modern chipsets. FIXME */
636
637 if (reason & 0x80)
638 mem_parity_error(reason, regs);
639 if (reason & 0x40)
640 io_check_error(reason, regs);
641}
642
b556b35e 643/* runs on IST stack. */
0f2fbdcb 644asmlinkage void __kprobes do_int3(struct pt_regs * regs, long error_code)
1da177e4
LT		 645{
646 if (notify_die(DIE_INT3, "int3", regs, error_code, 3, SIGTRAP) == NOTIFY_STOP) {
647 return;
648 }
649 do_trap(3, SIGTRAP, "int3", regs, error_code, NULL);
650 return;
651}
652
6fefb0d1
AK		 653/* Help handler running on IST stack to switch back to user stack
654 for scheduling or signal handling. The actual stack switch is done in
655 entry.S */
656asmlinkage struct pt_regs *sync_regs(struct pt_regs *eregs)
657{
658 struct pt_regs *regs = eregs;
659 /* Did already sync */
660 if (eregs == (struct pt_regs *)eregs->rsp)
661 ;
662 /* Exception from user space */
76381fee 663 else if (user_mode(eregs))
6fefb0d1
AK		 664 regs = ((struct pt_regs *)current->thread.rsp0) - 1;
665 /* Exception from kernel and interrupts are enabled. Move to
666 kernel process stack. */
667 else if (eregs->eflags & X86_EFLAGS_IF)
668 regs = (struct pt_regs *)(eregs->rsp -= sizeof(struct pt_regs));
669 if (eregs != regs)
670 *regs = *eregs;
671 return regs;
672}
673
1da177e4 674/* runs on IST stack. */
0f2fbdcb
PP		 675asmlinkage void __kprobes do_debug(struct pt_regs * regs,
676 unsigned long error_code)
1da177e4 677{
1da177e4
LT		 678 unsigned long condition;
679 struct task_struct *tsk = current;
680 siginfo_t info;
681
e9129e56 682 get_debugreg(condition, 6);
1da177e4
LT		 683
684 if (notify_die(DIE_DEBUG, "debug", regs, condition, error_code,
daeeafec 685 SIGTRAP) == NOTIFY_STOP)
6fefb0d1 686 return;
daeeafec 687
1da177e4
LT		 688 conditional_sti(regs);
689
690 /* Mask out spurious debug traps due to lazy DR7 setting */
691 if (condition & (DR_TRAP0|DR_TRAP1|DR_TRAP2|DR_TRAP3)) {
692 if (!tsk->thread.debugreg7) {
693 goto clear_dr7;
694 }
695 }
696
697 tsk->thread.debugreg6 = condition;
698
699 /* Mask out spurious TF errors due to lazy TF clearing */
daeeafec 700 if (condition & DR_STEP) {
1da177e4
LT		 701 /*
702 * The TF error should be masked out only if the current
703 * process is not traced and if the TRAP flag has been set
704 * previously by a tracing process (condition detected by
705 * the PT_DTRACE flag); remember that the i386 TRAP flag
706 * can be modified by the process itself in user mode,
707 * allowing programs to debug themselves without the ptrace()
708 * interface.
709 */
76381fee 710 if (!user_mode(regs))
1da177e4 711 goto clear_TF_reenable;
be61bff7
AK		 712 /*
713 * Was the TF flag set by a debugger? If so, clear it now,
714 * so that register information is correct.
715 */
716 if (tsk->ptrace & PT_DTRACE) {
717 regs->eflags &= ~TF_MASK;
718 tsk->ptrace &= ~PT_DTRACE;
719 }
1da177e4
LT		 720 }
721
722 /* Ok, finally something we can handle */
723 tsk->thread.trap_no = 1;
724 tsk->thread.error_code = error_code;
725 info.si_signo = SIGTRAP;
726 info.si_errno = 0;
727 info.si_code = TRAP_BRKPT;
01b8faae
JB		 728 info.si_addr = user_mode(regs) ? (void __user *)regs->rip : NULL;
729 force_sig_info(SIGTRAP, &info, tsk);
1da177e4 730
1da177e4 731clear_dr7:
e9129e56 732 set_debugreg(0UL, 7);
6fefb0d1 733 return;
1da177e4
LT		 734
735clear_TF_reenable:
736 set_tsk_thread_flag(tsk, TIF_SINGLESTEP);
1da177e4 737 regs->eflags &= ~TF_MASK;
1da177e4
LT		 738}
739
6e3f3617 740static int kernel_math_error(struct pt_regs *regs, const char *str, int trapnr)
1da177e4
LT		 741{
742 const struct exception_table_entry *fixup;
743 fixup = search_exception_tables(regs->rip);
744 if (fixup) {
745 regs->rip = fixup->fixup;
746 return 1;
747 }
6e3f3617 748 notify_die(DIE_GPF, str, regs, 0, trapnr, SIGFPE);
3a848f63 749 /* Illegal floating point operation in the kernel */
6e3f3617 750 current->thread.trap_no = trapnr;
1da177e4 751 die(str, regs, 0);
1da177e4
LT		 752 return 0;
753}
754
755/*
756 * Note that we play around with the 'TS' bit in an attempt to get
757 * the correct behaviour even in the presence of the asynchronous
758 * IRQ13 behaviour
759 */
760asmlinkage void do_coprocessor_error(struct pt_regs *regs)
761{
762 void __user *rip = (void __user *)(regs->rip);
763 struct task_struct * task;
764 siginfo_t info;
765 unsigned short cwd, swd;
766
767 conditional_sti(regs);
76381fee 768 if (!user_mode(regs) &&
6e3f3617 769 kernel_math_error(regs, "kernel x87 math error", 16))
1da177e4
LT		 770 return;
771
772 /*
773 * Save the info for the exception handler and clear the error.
774 */
775 task = current;
776 save_init_fpu(task);
777 task->thread.trap_no = 16;
778 task->thread.error_code = 0;
779 info.si_signo = SIGFPE;
780 info.si_errno = 0;
781 info.si_code = __SI_FAULT;
782 info.si_addr = rip;
783 /*
784 * (~cwd & swd) will mask out exceptions that are not set to unmasked
785 * status. 0x3f is the exception bits in these regs, 0x200 is the
786 * C1 reg you need in case of a stack fault, 0x040 is the stack
787 * fault bit. We should only be taking one exception at a time,
788 * so if this combination doesn't produce any single exception,
789 * then we have a bad program that isn't synchronizing its FPU usage
790 * and it will suffer the consequences since we won't be able to
791 * fully reproduce the context of the exception
792 */
793 cwd = get_fpu_cwd(task);
794 swd = get_fpu_swd(task);
ff347b22 795 switch (swd & ~cwd & 0x3f) {
1da177e4
LT		 796 case 0x000:
797 default:
798 break;
799 case 0x001: /* Invalid Op */
ff347b22
CE		 800 /*
801 * swd & 0x240 == 0x040: Stack Underflow
802 * swd & 0x240 == 0x240: Stack Overflow
803 * User must clear the SF bit (0x40) if set
804 */
1da177e4
LT		 805 info.si_code = FPE_FLTINV;
806 break;
807 case 0x002: /* Denormalize */
808 case 0x010: /* Underflow */
809 info.si_code = FPE_FLTUND;
810 break;
811 case 0x004: /* Zero Divide */
812 info.si_code = FPE_FLTDIV;
813 break;
814 case 0x008: /* Overflow */
815 info.si_code = FPE_FLTOVF;
816 break;
817 case 0x020: /* Precision */
818 info.si_code = FPE_FLTRES;
819 break;
820 }
821 force_sig_info(SIGFPE, &info, task);
822}
823
824asmlinkage void bad_intr(void)
825{
826 printk("bad interrupt");
827}
828
829asmlinkage void do_simd_coprocessor_error(struct pt_regs *regs)
830{
831 void __user *rip = (void __user *)(regs->rip);
832 struct task_struct * task;
833 siginfo_t info;
834 unsigned short mxcsr;
835
836 conditional_sti(regs);
76381fee 837 if (!user_mode(regs) &&
6e3f3617 838 kernel_math_error(regs, "kernel simd math error", 19))
1da177e4
LT		 839 return;
840
841 /*
842 * Save the info for the exception handler and clear the error.
843 */
844 task = current;
845 save_init_fpu(task);
846 task->thread.trap_no = 19;
847 task->thread.error_code = 0;
848 info.si_signo = SIGFPE;
849 info.si_errno = 0;
850 info.si_code = __SI_FAULT;
851 info.si_addr = rip;
852 /*
853 * The SIMD FPU exceptions are handled a little differently, as there
854 * is only a single status/control register. Thus, to determine which
855 * unmasked exception was caught we must mask the exception mask bits
856 * at 0x1f80, and then use these to mask the exception bits at 0x3f.
857 */
858 mxcsr = get_fpu_mxcsr(task);
859 switch (~((mxcsr & 0x1f80) >> 7) & (mxcsr & 0x3f)) {
860 case 0x000:
861 default:
862 break;
863 case 0x001: /* Invalid Op */
864 info.si_code = FPE_FLTINV;
865 break;
866 case 0x002: /* Denormalize */
867 case 0x010: /* Underflow */
868 info.si_code = FPE_FLTUND;
869 break;
870 case 0x004: /* Zero Divide */
871 info.si_code = FPE_FLTDIV;
872 break;
873 case 0x008: /* Overflow */
874 info.si_code = FPE_FLTOVF;
875 break;
876 case 0x020: /* Precision */
877 info.si_code = FPE_FLTRES;
878 break;
879 }
880 force_sig_info(SIGFPE, &info, task);
881}
882
883asmlinkage void do_spurious_interrupt_bug(struct pt_regs * regs)
884{
885}
886
887asmlinkage void __attribute__((weak)) smp_thermal_interrupt(void)
89b831ef
JS		 888{
889}
890
891asmlinkage void __attribute__((weak)) mce_threshold_interrupt(void)
1da177e4
LT		 892{
893}
894
895/*
896 * 'math_state_restore()' saves the current math information in the
897 * old math state array, and gets the new ones from the current task
898 *
899 * Careful.. There are problems with IBM-designed IRQ13 behaviour.
900 * Don't touch unless you *really* know how it works.
901 */
902asmlinkage void math_state_restore(void)
903{
904 struct task_struct *me = current;
905 clts(); /* Allow maths ops (or we recurse) */
906
907 if (!used_math())
908 init_fpu(me);
909 restore_fpu_checking(&me->thread.i387.fxsave);
910 me->thread_info->status |= TS_USEDFPU;
911}
912
1da177e4
LT		 913void __init trap_init(void)
914{
915 set_intr_gate(0,&divide_error);
916 set_intr_gate_ist(1,&debug,DEBUG_STACK);
917 set_intr_gate_ist(2,&nmi,NMI_STACK);
b556b35e 918 set_system_gate_ist(3,&int3,DEBUG_STACK); /* int3 can be called from all */
0a521588
JB		 919 set_system_gate(4,&overflow); /* int4 can be called from all */
920 set_intr_gate(5,&bounds);
1da177e4
LT		 921 set_intr_gate(6,&invalid_op);
922 set_intr_gate(7,&device_not_available);
923 set_intr_gate_ist(8,&double_fault, DOUBLEFAULT_STACK);
924 set_intr_gate(9,&coprocessor_segment_overrun);
925 set_intr_gate(10,&invalid_TSS);
926 set_intr_gate(11,&segment_not_present);
927 set_intr_gate_ist(12,&stack_segment,STACKFAULT_STACK);
928 set_intr_gate(13,&general_protection);
929 set_intr_gate(14,&page_fault);
930 set_intr_gate(15,&spurious_interrupt_bug);
931 set_intr_gate(16,&coprocessor_error);
932 set_intr_gate(17,&alignment_check);
933#ifdef CONFIG_X86_MCE
934 set_intr_gate_ist(18,&machine_check, MCE_STACK);
935#endif
936 set_intr_gate(19,&simd_coprocessor_error);
937
938#ifdef CONFIG_IA32_EMULATION
939 set_system_gate(IA32_SYSCALL_VECTOR, ia32_syscall);
940#endif
941
1da177e4
LT		 942 /*
943 * Should be a barrier for any external CPU state.
944 */
945 cpu_init();
946}
947
948
949/* Actual parsing is done early in setup.c. */
950static int __init oops_dummy(char *s)
951{
952 panic_on_oops = 1;
953 return -1;
954}
955__setup("oops=", oops_dummy);
956
957static int __init kstack_setup(char *s)
958{
959 kstack_depth_to_print = simple_strtoul(s,NULL,0);
960 return 0;
961}
962__setup("kstack=", kstack_setup);
963
kernel source for telekom puls (alcatel/mediatek)