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authorAlexander van Heukelum <heukelum@fastmail.fm>2008-10-03 16:00:40 -0400
committerIngo Molnar <mingo@elte.hu>2008-10-13 04:33:29 -0400
commit8728861b4fead8119a1b7bb856a387320859cd98 (patch)
tree03acdb0dccde800696409b6f59f8d5248c4da0f6 /arch/x86/kernel
parent081f75bbdc86de53537e1b5aca01de72bd2fea6b (diff)
traps: x86: finalize unification of traps.c
traps_32.c and traps_64.c are now equal. Move one to traps.c, delete the other one and change the Makefile Signed-off-by: Alexander van Heukelum <heukelum@fastmail.fm> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'arch/x86/kernel')
-rw-r--r--arch/x86/kernel/Makefile2
-rw-r--r--arch/x86/kernel/traps.c (renamed from arch/x86/kernel/traps_32.c)0
-rw-r--r--arch/x86/kernel/traps_64.c1070
3 files changed, 1 insertions, 1071 deletions
diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile
index de63fed9fae8..0d41f0343dc0 100644
--- a/arch/x86/kernel/Makefile
+++ b/arch/x86/kernel/Makefile
@@ -23,7 +23,7 @@ CFLAGS_hpet.o := $(nostackp)
23CFLAGS_tsc.o := $(nostackp) 23CFLAGS_tsc.o := $(nostackp)
24 24
25obj-y := process_$(BITS).o signal_$(BITS).o entry_$(BITS).o 25obj-y := process_$(BITS).o signal_$(BITS).o entry_$(BITS).o
26obj-y += traps_$(BITS).o irq_$(BITS).o dumpstack_$(BITS).o 26obj-y += traps.o irq_$(BITS).o dumpstack_$(BITS).o
27obj-y += time_$(BITS).o ioport.o ldt.o 27obj-y += time_$(BITS).o ioport.o ldt.o
28obj-y += setup.o i8259.o irqinit_$(BITS).o setup_percpu.o 28obj-y += setup.o i8259.o irqinit_$(BITS).o setup_percpu.o
29obj-$(CONFIG_X86_VISWS) += visws_quirks.o 29obj-$(CONFIG_X86_VISWS) += visws_quirks.o
diff --git a/arch/x86/kernel/traps_32.c b/arch/x86/kernel/traps.c
index ffb131f74f78..ffb131f74f78 100644
--- a/arch/x86/kernel/traps_32.c
+++ b/arch/x86/kernel/traps.c
diff --git a/arch/x86/kernel/traps_64.c b/arch/x86/kernel/traps_64.c
deleted file mode 100644
index 60ecc855ab81..000000000000
--- a/arch/x86/kernel/traps_64.c
+++ /dev/null
@@ -1,1070 +0,0 @@
1/*
2 * Copyright (C) 1991, 1992 Linus Torvalds
3 * Copyright (C) 2000, 2001, 2002 Andi Kleen, SuSE Labs
4 *
5 * Pentium III FXSR, SSE support
6 * Gareth Hughes <gareth@valinux.com>, May 2000
7 */
8
9/*
10 * Handle hardware traps and faults.
11 */
12#include <linux/interrupt.h>
13#include <linux/kallsyms.h>
14#include <linux/spinlock.h>
15#include <linux/kprobes.h>
16#include <linux/uaccess.h>
17#include <linux/utsname.h>
18#include <linux/kdebug.h>
19#include <linux/kernel.h>
20#include <linux/module.h>
21#include <linux/ptrace.h>
22#include <linux/string.h>
23#include <linux/unwind.h>
24#include <linux/delay.h>
25#include <linux/errno.h>
26#include <linux/kexec.h>
27#include <linux/sched.h>
28#include <linux/timer.h>
29#include <linux/init.h>
30#include <linux/bug.h>
31#include <linux/nmi.h>
32#include <linux/mm.h>
33#include <linux/smp.h>
34#include <linux/io.h>
35
36#ifdef CONFIG_EISA
37#include <linux/ioport.h>
38#include <linux/eisa.h>
39#endif
40
41#ifdef CONFIG_MCA
42#include <linux/mca.h>
43#endif
44
45#if defined(CONFIG_EDAC)
46#include <linux/edac.h>
47#endif
48
49#include <asm/stacktrace.h>
50#include <asm/processor.h>
51#include <asm/debugreg.h>
52#include <asm/atomic.h>
53#include <asm/system.h>
54#include <asm/unwind.h>
55#include <asm/traps.h>
56#include <asm/desc.h>
57#include <asm/i387.h>
58
59#include <mach_traps.h>
60
61#ifdef CONFIG_X86_64
62#include <asm/pgalloc.h>
63#include <asm/proto.h>
64#include <asm/pda.h>
65#else
66#include <asm/processor-flags.h>
67#include <asm/arch_hooks.h>
68#include <asm/nmi.h>
69#include <asm/smp.h>
70#include <asm/io.h>
71
72#include "cpu/mcheck/mce.h"
73
74DECLARE_BITMAP(used_vectors, NR_VECTORS);
75EXPORT_SYMBOL_GPL(used_vectors);
76
77asmlinkage int system_call(void);
78
79/* Do we ignore FPU interrupts ? */
80char ignore_fpu_irq;
81
82/*
83 * The IDT has to be page-aligned to simplify the Pentium
84 * F0 0F bug workaround.. We have a special link segment
85 * for this.
86 */
87gate_desc idt_table[256]
88 __attribute__((__section__(".data.idt"))) = { { { { 0, 0 } } }, };
89#endif
90
91static int ignore_nmis;
92
93static inline void conditional_sti(struct pt_regs *regs)
94{
95 if (regs->flags & X86_EFLAGS_IF)
96 local_irq_enable();
97}
98
99static inline void preempt_conditional_sti(struct pt_regs *regs)
100{
101 inc_preempt_count();
102 if (regs->flags & X86_EFLAGS_IF)
103 local_irq_enable();
104}
105
106static inline void preempt_conditional_cli(struct pt_regs *regs)
107{
108 if (regs->flags & X86_EFLAGS_IF)
109 local_irq_disable();
110 dec_preempt_count();
111}
112
113#ifdef CONFIG_X86_32
114static inline void
115die_if_kernel(const char *str, struct pt_regs *regs, long err)
116{
117 if (!user_mode_vm(regs))
118 die(str, regs, err);
119}
120
121/*
122 * Perform the lazy TSS's I/O bitmap copy. If the TSS has an
123 * invalid offset set (the LAZY one) and the faulting thread has
124 * a valid I/O bitmap pointer, we copy the I/O bitmap in the TSS,
125 * we set the offset field correctly and return 1.
126 */
127static int lazy_iobitmap_copy(void)
128{
129 struct thread_struct *thread;
130 struct tss_struct *tss;
131 int cpu;
132
133 cpu = get_cpu();
134 tss = &per_cpu(init_tss, cpu);
135 thread = &current->thread;
136
137 if (tss->x86_tss.io_bitmap_base == INVALID_IO_BITMAP_OFFSET_LAZY &&
138 thread->io_bitmap_ptr) {
139 memcpy(tss->io_bitmap, thread->io_bitmap_ptr,
140 thread->io_bitmap_max);
141 /*
142 * If the previously set map was extending to higher ports
143 * than the current one, pad extra space with 0xff (no access).
144 */
145 if (thread->io_bitmap_max < tss->io_bitmap_max) {
146 memset((char *) tss->io_bitmap +
147 thread->io_bitmap_max, 0xff,
148 tss->io_bitmap_max - thread->io_bitmap_max);
149 }
150 tss->io_bitmap_max = thread->io_bitmap_max;
151 tss->x86_tss.io_bitmap_base = IO_BITMAP_OFFSET;
152 tss->io_bitmap_owner = thread;
153 put_cpu();
154
155 return 1;
156 }
157 put_cpu();
158
159 return 0;
160}
161#endif
162
163static void __kprobes
164do_trap(int trapnr, int signr, char *str, struct pt_regs *regs,
165 long error_code, siginfo_t *info)
166{
167 struct task_struct *tsk = current;
168
169#ifdef CONFIG_X86_32
170 if (regs->flags & X86_VM_MASK) {
171 /*
172 * traps 0, 1, 3, 4, and 5 should be forwarded to vm86.
173 * On nmi (interrupt 2), do_trap should not be called.
174 */
175 if (trapnr < 6)
176 goto vm86_trap;
177 goto trap_signal;
178 }
179#endif
180
181 if (!user_mode(regs))
182 goto kernel_trap;
183
184#ifdef CONFIG_X86_32
185trap_signal:
186#endif
187 /*
188 * We want error_code and trap_no set for userspace faults and
189 * kernelspace faults which result in die(), but not
190 * kernelspace faults which are fixed up. die() gives the
191 * process no chance to handle the signal and notice the
192 * kernel fault information, so that won't result in polluting
193 * the information about previously queued, but not yet
194 * delivered, faults. See also do_general_protection below.
195 */
196 tsk->thread.error_code = error_code;
197 tsk->thread.trap_no = trapnr;
198
199#ifdef CONFIG_X86_64
200 if (show_unhandled_signals && unhandled_signal(tsk, signr) &&
201 printk_ratelimit()) {
202 printk(KERN_INFO
203 "%s[%d] trap %s ip:%lx sp:%lx error:%lx",
204 tsk->comm, tsk->pid, str,
205 regs->ip, regs->sp, error_code);
206 print_vma_addr(" in ", regs->ip);
207 printk("\n");
208 }
209#endif
210
211 if (info)
212 force_sig_info(signr, info, tsk);
213 else
214 force_sig(signr, tsk);
215 return;
216
217kernel_trap:
218 if (!fixup_exception(regs)) {
219 tsk->thread.error_code = error_code;
220 tsk->thread.trap_no = trapnr;
221 die(str, regs, error_code);
222 }
223 return;
224
225#ifdef CONFIG_X86_32
226vm86_trap:
227 if (handle_vm86_trap((struct kernel_vm86_regs *) regs,
228 error_code, trapnr))
229 goto trap_signal;
230 return;
231#endif
232}
233
234#define DO_ERROR(trapnr, signr, str, name) \
235dotraplinkage void do_##name(struct pt_regs *regs, long error_code) \
236{ \
237 if (notify_die(DIE_TRAP, str, regs, error_code, trapnr, signr) \
238 == NOTIFY_STOP) \
239 return; \
240 conditional_sti(regs); \
241 do_trap(trapnr, signr, str, regs, error_code, NULL); \
242}
243
244#define DO_ERROR_INFO(trapnr, signr, str, name, sicode, siaddr) \
245dotraplinkage void do_##name(struct pt_regs *regs, long error_code) \
246{ \
247 siginfo_t info; \
248 info.si_signo = signr; \
249 info.si_errno = 0; \
250 info.si_code = sicode; \
251 info.si_addr = (void __user *)siaddr; \
252 if (notify_die(DIE_TRAP, str, regs, error_code, trapnr, signr) \
253 == NOTIFY_STOP) \
254 return; \
255 conditional_sti(regs); \
256 do_trap(trapnr, signr, str, regs, error_code, &info); \
257}
258
259DO_ERROR_INFO(0, SIGFPE, "divide error", divide_error, FPE_INTDIV, regs->ip)
260DO_ERROR(4, SIGSEGV, "overflow", overflow)
261DO_ERROR(5, SIGSEGV, "bounds", bounds)
262DO_ERROR_INFO(6, SIGILL, "invalid opcode", invalid_op, ILL_ILLOPN, regs->ip)
263DO_ERROR(9, SIGFPE, "coprocessor segment overrun", coprocessor_segment_overrun)
264DO_ERROR(10, SIGSEGV, "invalid TSS", invalid_TSS)
265DO_ERROR(11, SIGBUS, "segment not present", segment_not_present)
266#ifdef CONFIG_X86_32
267DO_ERROR(12, SIGBUS, "stack segment", stack_segment)
268#endif
269DO_ERROR_INFO(17, SIGBUS, "alignment check", alignment_check, BUS_ADRALN, 0)
270
271#ifdef CONFIG_X86_64
272/* Runs on IST stack */
273dotraplinkage void do_stack_segment(struct pt_regs *regs, long error_code)
274{
275 if (notify_die(DIE_TRAP, "stack segment", regs, error_code,
276 12, SIGBUS) == NOTIFY_STOP)
277 return;
278 preempt_conditional_sti(regs);
279 do_trap(12, SIGBUS, "stack segment", regs, error_code, NULL);
280 preempt_conditional_cli(regs);
281}
282
283dotraplinkage void do_double_fault(struct pt_regs *regs, long error_code)
284{
285 static const char str[] = "double fault";
286 struct task_struct *tsk = current;
287
288 /* Return not checked because double check cannot be ignored */
289 notify_die(DIE_TRAP, str, regs, error_code, 8, SIGSEGV);
290
291 tsk->thread.error_code = error_code;
292 tsk->thread.trap_no = 8;
293
294 /* This is always a kernel trap and never fixable (and thus must
295 never return). */
296 for (;;)
297 die(str, regs, error_code);
298}
299#endif
300
301dotraplinkage void __kprobes
302do_general_protection(struct pt_regs *regs, long error_code)
303{
304 struct task_struct *tsk;
305
306 conditional_sti(regs);
307
308#ifdef CONFIG_X86_32
309 if (lazy_iobitmap_copy()) {
310 /* restart the faulting instruction */
311 return;
312 }
313
314 if (regs->flags & X86_VM_MASK)
315 goto gp_in_vm86;
316#endif
317
318 tsk = current;
319 if (!user_mode(regs))
320 goto gp_in_kernel;
321
322 tsk->thread.error_code = error_code;
323 tsk->thread.trap_no = 13;
324
325 if (show_unhandled_signals && unhandled_signal(tsk, SIGSEGV) &&
326 printk_ratelimit()) {
327 printk(KERN_INFO
328 "%s[%d] general protection ip:%lx sp:%lx error:%lx",
329 tsk->comm, task_pid_nr(tsk),
330 regs->ip, regs->sp, error_code);
331 print_vma_addr(" in ", regs->ip);
332 printk("\n");
333 }
334
335 force_sig(SIGSEGV, tsk);
336 return;
337
338#ifdef CONFIG_X86_32
339gp_in_vm86:
340 local_irq_enable();
341 handle_vm86_fault((struct kernel_vm86_regs *) regs, error_code);
342 return;
343#endif
344
345gp_in_kernel:
346 if (fixup_exception(regs))
347 return;
348
349 tsk->thread.error_code = error_code;
350 tsk->thread.trap_no = 13;
351 if (notify_die(DIE_GPF, "general protection fault", regs,
352 error_code, 13, SIGSEGV) == NOTIFY_STOP)
353 return;
354 die("general protection fault", regs, error_code);
355}
356
357static notrace __kprobes void
358mem_parity_error(unsigned char reason, struct pt_regs *regs)
359{
360 printk(KERN_EMERG
361 "Uhhuh. NMI received for unknown reason %02x on CPU %d.\n",
362 reason, smp_processor_id());
363
364 printk(KERN_EMERG
365 "You have some hardware problem, likely on the PCI bus.\n");
366
367#if defined(CONFIG_EDAC)
368 if (edac_handler_set()) {
369 edac_atomic_assert_error();
370 return;
371 }
372#endif
373
374 if (panic_on_unrecovered_nmi)
375 panic("NMI: Not continuing");
376
377 printk(KERN_EMERG "Dazed and confused, but trying to continue\n");
378
379 /* Clear and disable the memory parity error line. */
380 reason = (reason & 0xf) | 4;
381 outb(reason, 0x61);
382}
383
384static notrace __kprobes void
385io_check_error(unsigned char reason, struct pt_regs *regs)
386{
387 unsigned long i;
388
389 printk(KERN_EMERG "NMI: IOCK error (debug interrupt?)\n");
390 show_registers(regs);
391
392 /* Re-enable the IOCK line, wait for a few seconds */
393 reason = (reason & 0xf) | 8;
394 outb(reason, 0x61);
395
396 i = 2000;
397 while (--i)
398 udelay(1000);
399
400 reason &= ~8;
401 outb(reason, 0x61);
402}
403
404static notrace __kprobes void
405unknown_nmi_error(unsigned char reason, struct pt_regs *regs)
406{
407 if (notify_die(DIE_NMIUNKNOWN, "nmi", regs, reason, 2, SIGINT) ==
408 NOTIFY_STOP)
409 return;
410#ifdef CONFIG_MCA
411 /*
412 * Might actually be able to figure out what the guilty party
413 * is:
414 */
415 if (MCA_bus) {
416 mca_handle_nmi();
417 return;
418 }
419#endif
420 printk(KERN_EMERG
421 "Uhhuh. NMI received for unknown reason %02x on CPU %d.\n",
422 reason, smp_processor_id());
423
424 printk(KERN_EMERG "Do you have a strange power saving mode enabled?\n");
425 if (panic_on_unrecovered_nmi)
426 panic("NMI: Not continuing");
427
428 printk(KERN_EMERG "Dazed and confused, but trying to continue\n");
429}
430
431#ifdef CONFIG_X86_32
432static DEFINE_SPINLOCK(nmi_print_lock);
433
434void notrace __kprobes die_nmi(char *str, struct pt_regs *regs, int do_panic)
435{
436 if (notify_die(DIE_NMIWATCHDOG, str, regs, 0, 2, SIGINT) == NOTIFY_STOP)
437 return;
438
439 spin_lock(&nmi_print_lock);
440 /*
441 * We are in trouble anyway, lets at least try
442 * to get a message out:
443 */
444 bust_spinlocks(1);
445 printk(KERN_EMERG "%s", str);
446 printk(" on CPU%d, ip %08lx, registers:\n",
447 smp_processor_id(), regs->ip);
448 show_registers(regs);
449 if (do_panic)
450 panic("Non maskable interrupt");
451 console_silent();
452 spin_unlock(&nmi_print_lock);
453 bust_spinlocks(0);
454
455 /*
456 * If we are in kernel we are probably nested up pretty bad
457 * and might aswell get out now while we still can:
458 */
459 if (!user_mode_vm(regs)) {
460 current->thread.trap_no = 2;
461 crash_kexec(regs);
462 }
463
464 do_exit(SIGSEGV);
465}
466#endif
467
468static notrace __kprobes void default_do_nmi(struct pt_regs *regs)
469{
470 unsigned char reason = 0;
471 int cpu;
472
473 cpu = smp_processor_id();
474
475 /* Only the BSP gets external NMIs from the system. */
476 if (!cpu)
477 reason = get_nmi_reason();
478
479 if (!(reason & 0xc0)) {
480 if (notify_die(DIE_NMI_IPI, "nmi_ipi", regs, reason, 2, SIGINT)
481 == NOTIFY_STOP)
482 return;
483#ifdef CONFIG_X86_LOCAL_APIC
484 /*
485 * Ok, so this is none of the documented NMI sources,
486 * so it must be the NMI watchdog.
487 */
488 if (nmi_watchdog_tick(regs, reason))
489 return;
490 if (!do_nmi_callback(regs, cpu))
491 unknown_nmi_error(reason, regs);
492#else
493 unknown_nmi_error(reason, regs);
494#endif
495
496 return;
497 }
498 if (notify_die(DIE_NMI, "nmi", regs, reason, 2, SIGINT) == NOTIFY_STOP)
499 return;
500
501 /* AK: following checks seem to be broken on modern chipsets. FIXME */
502 if (reason & 0x80)
503 mem_parity_error(reason, regs);
504 if (reason & 0x40)
505 io_check_error(reason, regs);
506#ifdef CONFIG_X86_32
507 /*
508 * Reassert NMI in case it became active meanwhile
509 * as it's edge-triggered:
510 */
511 reassert_nmi();
512#endif
513}
514
515dotraplinkage notrace __kprobes void
516do_nmi(struct pt_regs *regs, long error_code)
517{
518 nmi_enter();
519
520#ifdef CONFIG_X86_32
521 { int cpu; cpu = smp_processor_id(); ++nmi_count(cpu); }
522#else
523 add_pda(__nmi_count, 1);
524#endif
525
526 if (!ignore_nmis)
527 default_do_nmi(regs);
528
529 nmi_exit();
530}
531
532void stop_nmi(void)
533{
534 acpi_nmi_disable();
535 ignore_nmis++;
536}
537
538void restart_nmi(void)
539{
540 ignore_nmis--;
541 acpi_nmi_enable();
542}
543
544/* May run on IST stack. */
545dotraplinkage void __kprobes do_int3(struct pt_regs *regs, long error_code)
546{
547#ifdef CONFIG_KPROBES
548 if (notify_die(DIE_INT3, "int3", regs, error_code, 3, SIGTRAP)
549 == NOTIFY_STOP)
550 return;
551#else
552 if (notify_die(DIE_TRAP, "int3", regs, error_code, 3, SIGTRAP)
553 == NOTIFY_STOP)
554 return;
555#endif
556
557 preempt_conditional_sti(regs);
558 do_trap(3, SIGTRAP, "int3", regs, error_code, NULL);
559 preempt_conditional_cli(regs);
560}
561
562#ifdef CONFIG_X86_64
563/* Help handler running on IST stack to switch back to user stack
564 for scheduling or signal handling. The actual stack switch is done in
565 entry.S */
566asmlinkage __kprobes struct pt_regs *sync_regs(struct pt_regs *eregs)
567{
568 struct pt_regs *regs = eregs;
569 /* Did already sync */
570 if (eregs == (struct pt_regs *)eregs->sp)
571 ;
572 /* Exception from user space */
573 else if (user_mode(eregs))
574 regs = task_pt_regs(current);
575 /* Exception from kernel and interrupts are enabled. Move to
576 kernel process stack. */
577 else if (eregs->flags & X86_EFLAGS_IF)
578 regs = (struct pt_regs *)(eregs->sp -= sizeof(struct pt_regs));
579 if (eregs != regs)
580 *regs = *eregs;
581 return regs;
582}
583#endif
584
585/*
586 * Our handling of the processor debug registers is non-trivial.
587 * We do not clear them on entry and exit from the kernel. Therefore
588 * it is possible to get a watchpoint trap here from inside the kernel.
589 * However, the code in ./ptrace.c has ensured that the user can
590 * only set watchpoints on userspace addresses. Therefore the in-kernel
591 * watchpoint trap can only occur in code which is reading/writing
592 * from user space. Such code must not hold kernel locks (since it
593 * can equally take a page fault), therefore it is safe to call
594 * force_sig_info even though that claims and releases locks.
595 *
596 * Code in ./signal.c ensures that the debug control register
597 * is restored before we deliver any signal, and therefore that
598 * user code runs with the correct debug control register even though
599 * we clear it here.
600 *
601 * Being careful here means that we don't have to be as careful in a
602 * lot of more complicated places (task switching can be a bit lazy
603 * about restoring all the debug state, and ptrace doesn't have to
604 * find every occurrence of the TF bit that could be saved away even
605 * by user code)
606 *
607 * May run on IST stack.
608 */
609dotraplinkage void __kprobes do_debug(struct pt_regs *regs, long error_code)
610{
611 struct task_struct *tsk = current;
612 unsigned long condition;
613 int si_code;
614
615 get_debugreg(condition, 6);
616
617 /*
618 * The processor cleared BTF, so don't mark that we need it set.
619 */
620 clear_tsk_thread_flag(tsk, TIF_DEBUGCTLMSR);
621 tsk->thread.debugctlmsr = 0;
622
623 if (notify_die(DIE_DEBUG, "debug", regs, condition, error_code,
624 SIGTRAP) == NOTIFY_STOP)
625 return;
626
627 /* It's safe to allow irq's after DR6 has been saved */
628 preempt_conditional_sti(regs);
629
630 /* Mask out spurious debug traps due to lazy DR7 setting */
631 if (condition & (DR_TRAP0|DR_TRAP1|DR_TRAP2|DR_TRAP3)) {
632 if (!tsk->thread.debugreg7)
633 goto clear_dr7;
634 }
635
636#ifdef CONFIG_X86_32
637 if (regs->flags & X86_VM_MASK)
638 goto debug_vm86;
639#endif
640
641 /* Save debug status register where ptrace can see it */
642 tsk->thread.debugreg6 = condition;
643
644 /*
645 * Single-stepping through TF: make sure we ignore any events in
646 * kernel space (but re-enable TF when returning to user mode).
647 */
648 if (condition & DR_STEP) {
649 if (!user_mode(regs))
650 goto clear_TF_reenable;
651 }
652
653 si_code = get_si_code(condition);
654 /* Ok, finally something we can handle */
655 send_sigtrap(tsk, regs, error_code, si_code);
656
657 /*
658 * Disable additional traps. They'll be re-enabled when
659 * the signal is delivered.
660 */
661clear_dr7:
662 set_debugreg(0, 7);
663 preempt_conditional_cli(regs);
664 return;
665
666#ifdef CONFIG_X86_32
667debug_vm86:
668 handle_vm86_trap((struct kernel_vm86_regs *) regs, error_code, 1);
669 preempt_conditional_cli(regs);
670 return;
671#endif
672
673clear_TF_reenable:
674 set_tsk_thread_flag(tsk, TIF_SINGLESTEP);
675 regs->flags &= ~X86_EFLAGS_TF;
676 preempt_conditional_cli(regs);
677 return;
678}
679
680#ifdef CONFIG_X86_64
681static int kernel_math_error(struct pt_regs *regs, const char *str, int trapnr)
682{
683 if (fixup_exception(regs))
684 return 1;
685
686 notify_die(DIE_GPF, str, regs, 0, trapnr, SIGFPE);
687 /* Illegal floating point operation in the kernel */
688 current->thread.trap_no = trapnr;
689 die(str, regs, 0);
690 return 0;
691}
692#endif
693
694/*
695 * Note that we play around with the 'TS' bit in an attempt to get
696 * the correct behaviour even in the presence of the asynchronous
697 * IRQ13 behaviour
698 */
699void math_error(void __user *ip)
700{
701 struct task_struct *task;
702 siginfo_t info;
703 unsigned short cwd, swd;
704
705 /*
706 * Save the info for the exception handler and clear the error.
707 */
708 task = current;
709 save_init_fpu(task);
710 task->thread.trap_no = 16;
711 task->thread.error_code = 0;
712 info.si_signo = SIGFPE;
713 info.si_errno = 0;
714 info.si_code = __SI_FAULT;
715 info.si_addr = ip;
716 /*
717 * (~cwd & swd) will mask out exceptions that are not set to unmasked
718 * status. 0x3f is the exception bits in these regs, 0x200 is the
719 * C1 reg you need in case of a stack fault, 0x040 is the stack
720 * fault bit. We should only be taking one exception at a time,
721 * so if this combination doesn't produce any single exception,
722 * then we have a bad program that isn't synchronizing its FPU usage
723 * and it will suffer the consequences since we won't be able to
724 * fully reproduce the context of the exception
725 */
726 cwd = get_fpu_cwd(task);
727 swd = get_fpu_swd(task);
728 switch (swd & ~cwd & 0x3f) {
729 case 0x000: /* No unmasked exception */
730#ifdef CONFIG_X86_32
731 return;
732#endif
733 default: /* Multiple exceptions */
734 break;
735 case 0x001: /* Invalid Op */
736 /*
737 * swd & 0x240 == 0x040: Stack Underflow
738 * swd & 0x240 == 0x240: Stack Overflow
739 * User must clear the SF bit (0x40) if set
740 */
741 info.si_code = FPE_FLTINV;
742 break;
743 case 0x002: /* Denormalize */
744 case 0x010: /* Underflow */
745 info.si_code = FPE_FLTUND;
746 break;
747 case 0x004: /* Zero Divide */
748 info.si_code = FPE_FLTDIV;
749 break;
750 case 0x008: /* Overflow */
751 info.si_code = FPE_FLTOVF;
752 break;
753 case 0x020: /* Precision */
754 info.si_code = FPE_FLTRES;
755 break;
756 }
757 force_sig_info(SIGFPE, &info, task);
758}
759
760dotraplinkage void do_coprocessor_error(struct pt_regs *regs, long error_code)
761{
762 conditional_sti(regs);
763
764#ifdef CONFIG_X86_32
765 ignore_fpu_irq = 1;
766#else
767 if (!user_mode(regs) &&
768 kernel_math_error(regs, "kernel x87 math error", 16))
769 return;
770#endif
771
772 math_error((void __user *)regs->ip);
773}
774
775static void simd_math_error(void __user *ip)
776{
777 struct task_struct *task;
778 siginfo_t info;
779 unsigned short mxcsr;
780
781 /*
782 * Save the info for the exception handler and clear the error.
783 */
784 task = current;
785 save_init_fpu(task);
786 task->thread.trap_no = 19;
787 task->thread.error_code = 0;
788 info.si_signo = SIGFPE;
789 info.si_errno = 0;
790 info.si_code = __SI_FAULT;
791 info.si_addr = ip;
792 /*
793 * The SIMD FPU exceptions are handled a little differently, as there
794 * is only a single status/control register. Thus, to determine which
795 * unmasked exception was caught we must mask the exception mask bits
796 * at 0x1f80, and then use these to mask the exception bits at 0x3f.
797 */
798 mxcsr = get_fpu_mxcsr(task);
799 switch (~((mxcsr & 0x1f80) >> 7) & (mxcsr & 0x3f)) {
800 case 0x000:
801 default:
802 break;
803 case 0x001: /* Invalid Op */
804 info.si_code = FPE_FLTINV;
805 break;
806 case 0x002: /* Denormalize */
807 case 0x010: /* Underflow */
808 info.si_code = FPE_FLTUND;
809 break;
810 case 0x004: /* Zero Divide */
811 info.si_code = FPE_FLTDIV;
812 break;
813 case 0x008: /* Overflow */
814 info.si_code = FPE_FLTOVF;
815 break;
816 case 0x020: /* Precision */
817 info.si_code = FPE_FLTRES;
818 break;
819 }
820 force_sig_info(SIGFPE, &info, task);
821}
822
823dotraplinkage void
824do_simd_coprocessor_error(struct pt_regs *regs, long error_code)
825{
826 conditional_sti(regs);
827
828#ifdef CONFIG_X86_32
829 if (cpu_has_xmm) {
830 /* Handle SIMD FPU exceptions on PIII+ processors. */
831 ignore_fpu_irq = 1;
832 simd_math_error((void __user *)regs->ip);
833 return;
834 }
835 /*
836 * Handle strange cache flush from user space exception
837 * in all other cases. This is undocumented behaviour.
838 */
839 if (regs->flags & X86_VM_MASK) {
840 handle_vm86_fault((struct kernel_vm86_regs *)regs, error_code);
841 return;
842 }
843 current->thread.trap_no = 19;
844 current->thread.error_code = error_code;
845 die_if_kernel("cache flush denied", regs, error_code);
846 force_sig(SIGSEGV, current);
847#else
848 if (!user_mode(regs) &&
849 kernel_math_error(regs, "kernel simd math error", 19))
850 return;
851 simd_math_error((void __user *)regs->ip);
852#endif
853}
854
855dotraplinkage void
856do_spurious_interrupt_bug(struct pt_regs *regs, long error_code)
857{
858 conditional_sti(regs);
859#if 0
860 /* No need to warn about this any longer. */
861 printk(KERN_INFO "Ignoring P6 Local APIC Spurious Interrupt Bug...\n");
862#endif
863}
864
865#ifdef CONFIG_X86_32
866unsigned long patch_espfix_desc(unsigned long uesp, unsigned long kesp)
867{
868 struct desc_struct *gdt = get_cpu_gdt_table(smp_processor_id());
869 unsigned long base = (kesp - uesp) & -THREAD_SIZE;
870 unsigned long new_kesp = kesp - base;
871 unsigned long lim_pages = (new_kesp | (THREAD_SIZE - 1)) >> PAGE_SHIFT;
872 __u64 desc = *(__u64 *)&gdt[GDT_ENTRY_ESPFIX_SS];
873
874 /* Set up base for espfix segment */
875 desc &= 0x00f0ff0000000000ULL;
876 desc |= ((((__u64)base) << 16) & 0x000000ffffff0000ULL) |
877 ((((__u64)base) << 32) & 0xff00000000000000ULL) |
878 ((((__u64)lim_pages) << 32) & 0x000f000000000000ULL) |
879 (lim_pages & 0xffff);
880 *(__u64 *)&gdt[GDT_ENTRY_ESPFIX_SS] = desc;
881
882 return new_kesp;
883}
884#else
885asmlinkage void __attribute__((weak)) smp_thermal_interrupt(void)
886{
887}
888
889asmlinkage void __attribute__((weak)) mce_threshold_interrupt(void)
890{
891}
892#endif
893
894/*
895 * 'math_state_restore()' saves the current math information in the
896 * old math state array, and gets the new ones from the current task
897 *
898 * Careful.. There are problems with IBM-designed IRQ13 behaviour.
899 * Don't touch unless you *really* know how it works.
900 *
901 * Must be called with kernel preemption disabled (in this case,
902 * local interrupts are disabled at the call-site in entry.S).
903 */
904asmlinkage void math_state_restore(void)
905{
906 struct thread_info *thread = current_thread_info();
907 struct task_struct *tsk = thread->task;
908
909 if (!tsk_used_math(tsk)) {
910 local_irq_enable();
911 /*
912 * does a slab alloc which can sleep
913 */
914 if (init_fpu(tsk)) {
915 /*
916 * ran out of memory!
917 */
918 do_group_exit(SIGKILL);
919 return;
920 }
921 local_irq_disable();
922 }
923
924 clts(); /* Allow maths ops (or we recurse) */
925#ifdef CONFIG_X86_32
926 restore_fpu(tsk);
927#else
928 /*
929 * Paranoid restore. send a SIGSEGV if we fail to restore the state.
930 */
931 if (unlikely(restore_fpu_checking(tsk))) {
932 stts();
933 force_sig(SIGSEGV, tsk);
934 return;
935 }
936#endif
937 thread->status |= TS_USEDFPU; /* So we fnsave on switch_to() */
938 tsk->fpu_counter++;
939}
940EXPORT_SYMBOL_GPL(math_state_restore);
941
942#ifndef CONFIG_MATH_EMULATION
943asmlinkage void math_emulate(long arg)
944{
945 printk(KERN_EMERG
946 "math-emulation not enabled and no coprocessor found.\n");
947 printk(KERN_EMERG "killing %s.\n", current->comm);
948 force_sig(SIGFPE, current);
949 schedule();
950}
951#endif /* CONFIG_MATH_EMULATION */
952
953dotraplinkage void __kprobes
954do_device_not_available(struct pt_regs *regs, long error)
955{
956#ifdef CONFIG_X86_32
957 if (read_cr0() & X86_CR0_EM) {
958 conditional_sti(regs);
959 math_emulate(0);
960 } else {
961 math_state_restore(); /* interrupts still off */
962 conditional_sti(regs);
963 }
964#else
965 math_state_restore();
966#endif
967}
968
969#ifdef CONFIG_X86_32
970#ifdef CONFIG_X86_MCE
971dotraplinkage void __kprobes do_machine_check(struct pt_regs *regs, long error)
972{
973 conditional_sti(regs);
974 machine_check_vector(regs, error);
975}
976#endif
977
978dotraplinkage void do_iret_error(struct pt_regs *regs, long error_code)
979{
980 siginfo_t info;
981 local_irq_enable();
982
983 info.si_signo = SIGILL;
984 info.si_errno = 0;
985 info.si_code = ILL_BADSTK;
986 info.si_addr = 0;
987 if (notify_die(DIE_TRAP, "iret exception",
988 regs, error_code, 32, SIGILL) == NOTIFY_STOP)
989 return;
990 do_trap(32, SIGILL, "iret exception", regs, error_code, &info);
991}
992#endif
993
994void __init trap_init(void)
995{
996#ifdef CONFIG_X86_32
997 int i;
998#endif
999
1000#ifdef CONFIG_EISA
1001 void __iomem *p = early_ioremap(0x0FFFD9, 4);
1002
1003 if (readl(p) == 'E' + ('I'<<8) + ('S'<<16) + ('A'<<24))
1004 EISA_bus = 1;
1005 early_iounmap(p, 4);
1006#endif
1007
1008 set_intr_gate(0, &divide_error);
1009 set_intr_gate_ist(1, &debug, DEBUG_STACK);
1010 set_intr_gate_ist(2, &nmi, NMI_STACK);
1011 /* int3 can be called from all */
1012 set_system_intr_gate_ist(3, &int3, DEBUG_STACK);
1013 /* int4 can be called from all */
1014 set_system_intr_gate(4, &overflow);
1015 set_intr_gate(5, &bounds);
1016 set_intr_gate(6, &invalid_op);
1017 set_intr_gate(7, &device_not_available);
1018#ifdef CONFIG_X86_32
1019 set_task_gate(8, GDT_ENTRY_DOUBLEFAULT_TSS);
1020#else
1021 set_intr_gate_ist(8, &double_fault, DOUBLEFAULT_STACK);
1022#endif
1023 set_intr_gate(9, &coprocessor_segment_overrun);
1024 set_intr_gate(10, &invalid_TSS);
1025 set_intr_gate(11, &segment_not_present);
1026 set_intr_gate_ist(12, &stack_segment, STACKFAULT_STACK);
1027 set_intr_gate(13, &general_protection);
1028 set_intr_gate(14, &page_fault);
1029 set_intr_gate(15, &spurious_interrupt_bug);
1030 set_intr_gate(16, &coprocessor_error);
1031 set_intr_gate(17, &alignment_check);
1032#ifdef CONFIG_X86_MCE
1033 set_intr_gate_ist(18, &machine_check, MCE_STACK);
1034#endif
1035 set_intr_gate(19, &simd_coprocessor_error);
1036
1037#ifdef CONFIG_IA32_EMULATION
1038 set_system_intr_gate(IA32_SYSCALL_VECTOR, ia32_syscall);
1039#endif
1040
1041#ifdef CONFIG_X86_32
1042 if (cpu_has_fxsr) {
1043 printk(KERN_INFO "Enabling fast FPU save and restore... ");
1044 set_in_cr4(X86_CR4_OSFXSR);
1045 printk("done.\n");
1046 }
1047 if (cpu_has_xmm) {
1048 printk(KERN_INFO
1049 "Enabling unmasked SIMD FPU exception support... ");
1050 set_in_cr4(X86_CR4_OSXMMEXCPT);
1051 printk("done.\n");
1052 }
1053
1054 set_system_trap_gate(SYSCALL_VECTOR, &system_call);
1055
1056 /* Reserve all the builtin and the syscall vector: */
1057 for (i = 0; i < FIRST_EXTERNAL_VECTOR; i++)
1058 set_bit(i, used_vectors);
1059
1060 set_bit(SYSCALL_VECTOR, used_vectors);
1061#endif
1062 /*
1063 * Should be a barrier for any external CPU state:
1064 */
1065 cpu_init();
1066
1067#ifdef CONFIG_X86_32
1068 trap_init_hook();
1069#endif
1070}
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