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[deliverable/linux.git] / arch / i386 / kernel / entry.S
1 /*
2 * linux/arch/i386/entry.S
3 *
4 * Copyright (C) 1991, 1992 Linus Torvalds
5 */
6
7 /*
8 * entry.S contains the system-call and fault low-level handling routines.
9 * This also contains the timer-interrupt handler, as well as all interrupts
10 * and faults that can result in a task-switch.
11 *
12 * NOTE: This code handles signal-recognition, which happens every time
13 * after a timer-interrupt and after each system call.
14 *
15 * I changed all the .align's to 4 (16 byte alignment), as that's faster
16 * on a 486.
17 *
18 * Stack layout in 'ret_from_system_call':
19 * ptrace needs to have all regs on the stack.
20 * if the order here is changed, it needs to be
21 * updated in fork.c:copy_process, signal.c:do_signal,
22 * ptrace.c and ptrace.h
23 *
24 * 0(%esp) - %ebx
25 * 4(%esp) - %ecx
26 * 8(%esp) - %edx
27 * C(%esp) - %esi
28 * 10(%esp) - %edi
29 * 14(%esp) - %ebp
30 * 18(%esp) - %eax
31 * 1C(%esp) - %ds
32 * 20(%esp) - %es
33 * 24(%esp) - orig_eax
34 * 28(%esp) - %eip
35 * 2C(%esp) - %cs
36 * 30(%esp) - %eflags
37 * 34(%esp) - %oldesp
38 * 38(%esp) - %oldss
39 *
40 * "current" is in register %ebx during any slow entries.
41 */
42
43 #include <linux/config.h>
44 #include <linux/linkage.h>
45 #include <asm/thread_info.h>
46 #include <asm/errno.h>
47 #include <asm/segment.h>
48 #include <asm/smp.h>
49 #include <asm/page.h>
50 #include <asm/desc.h>
51 #include <asm/dwarf2.h>
52 #include "irq_vectors.h"
53
54 #define nr_syscalls ((syscall_table_size)/4)
55
56 EBX = 0x00
57 ECX = 0x04
58 EDX = 0x08
59 ESI = 0x0C
60 EDI = 0x10
61 EBP = 0x14
62 EAX = 0x18
63 DS = 0x1C
64 ES = 0x20
65 ORIG_EAX = 0x24
66 EIP = 0x28
67 CS = 0x2C
68 EFLAGS = 0x30
69 OLDESP = 0x34
70 OLDSS = 0x38
71
72 CF_MASK = 0x00000001
73 TF_MASK = 0x00000100
74 IF_MASK = 0x00000200
75 DF_MASK = 0x00000400
76 NT_MASK = 0x00004000
77 VM_MASK = 0x00020000
78
79 #ifdef CONFIG_PREEMPT
80 #define preempt_stop cli
81 #else
82 #define preempt_stop
83 #define resume_kernel restore_nocheck
84 #endif
85
86 #define SAVE_ALL \
87 cld; \
88 pushl %es; \
89 CFI_ADJUST_CFA_OFFSET 4;\
90 /*CFI_REL_OFFSET es, 0;*/\
91 pushl %ds; \
92 CFI_ADJUST_CFA_OFFSET 4;\
93 /*CFI_REL_OFFSET ds, 0;*/\
94 pushl %eax; \
95 CFI_ADJUST_CFA_OFFSET 4;\
96 CFI_REL_OFFSET eax, 0;\
97 pushl %ebp; \
98 CFI_ADJUST_CFA_OFFSET 4;\
99 CFI_REL_OFFSET ebp, 0;\
100 pushl %edi; \
101 CFI_ADJUST_CFA_OFFSET 4;\
102 CFI_REL_OFFSET edi, 0;\
103 pushl %esi; \
104 CFI_ADJUST_CFA_OFFSET 4;\
105 CFI_REL_OFFSET esi, 0;\
106 pushl %edx; \
107 CFI_ADJUST_CFA_OFFSET 4;\
108 CFI_REL_OFFSET edx, 0;\
109 pushl %ecx; \
110 CFI_ADJUST_CFA_OFFSET 4;\
111 CFI_REL_OFFSET ecx, 0;\
112 pushl %ebx; \
113 CFI_ADJUST_CFA_OFFSET 4;\
114 CFI_REL_OFFSET ebx, 0;\
115 movl $(__USER_DS), %edx; \
116 movl %edx, %ds; \
117 movl %edx, %es;
118
119 #define RESTORE_INT_REGS \
120 popl %ebx; \
121 CFI_ADJUST_CFA_OFFSET -4;\
122 CFI_RESTORE ebx;\
123 popl %ecx; \
124 CFI_ADJUST_CFA_OFFSET -4;\
125 CFI_RESTORE ecx;\
126 popl %edx; \
127 CFI_ADJUST_CFA_OFFSET -4;\
128 CFI_RESTORE edx;\
129 popl %esi; \
130 CFI_ADJUST_CFA_OFFSET -4;\
131 CFI_RESTORE esi;\
132 popl %edi; \
133 CFI_ADJUST_CFA_OFFSET -4;\
134 CFI_RESTORE edi;\
135 popl %ebp; \
136 CFI_ADJUST_CFA_OFFSET -4;\
137 CFI_RESTORE ebp;\
138 popl %eax; \
139 CFI_ADJUST_CFA_OFFSET -4;\
140 CFI_RESTORE eax
141
142 #define RESTORE_REGS \
143 RESTORE_INT_REGS; \
144 1: popl %ds; \
145 CFI_ADJUST_CFA_OFFSET -4;\
146 /*CFI_RESTORE ds;*/\
147 2: popl %es; \
148 CFI_ADJUST_CFA_OFFSET -4;\
149 /*CFI_RESTORE es;*/\
150 .section .fixup,"ax"; \
151 3: movl $0,(%esp); \
152 jmp 1b; \
153 4: movl $0,(%esp); \
154 jmp 2b; \
155 .previous; \
156 .section __ex_table,"a";\
157 .align 4; \
158 .long 1b,3b; \
159 .long 2b,4b; \
160 .previous
161
162 #define RING0_INT_FRAME \
163 CFI_STARTPROC simple;\
164 CFI_DEF_CFA esp, 3*4;\
165 /*CFI_OFFSET cs, -2*4;*/\
166 CFI_OFFSET eip, -3*4
167
168 #define RING0_EC_FRAME \
169 CFI_STARTPROC simple;\
170 CFI_DEF_CFA esp, 4*4;\
171 /*CFI_OFFSET cs, -2*4;*/\
172 CFI_OFFSET eip, -3*4
173
174 #define RING0_PTREGS_FRAME \
175 CFI_STARTPROC simple;\
176 CFI_DEF_CFA esp, OLDESP-EBX;\
177 /*CFI_OFFSET cs, CS-OLDESP;*/\
178 CFI_OFFSET eip, EIP-OLDESP;\
179 /*CFI_OFFSET es, ES-OLDESP;*/\
180 /*CFI_OFFSET ds, DS-OLDESP;*/\
181 CFI_OFFSET eax, EAX-OLDESP;\
182 CFI_OFFSET ebp, EBP-OLDESP;\
183 CFI_OFFSET edi, EDI-OLDESP;\
184 CFI_OFFSET esi, ESI-OLDESP;\
185 CFI_OFFSET edx, EDX-OLDESP;\
186 CFI_OFFSET ecx, ECX-OLDESP;\
187 CFI_OFFSET ebx, EBX-OLDESP
188
189 ENTRY(ret_from_fork)
190 CFI_STARTPROC
191 pushl %eax
192 CFI_ADJUST_CFA_OFFSET -4
193 call schedule_tail
194 GET_THREAD_INFO(%ebp)
195 popl %eax
196 CFI_ADJUST_CFA_OFFSET -4
197 jmp syscall_exit
198 CFI_ENDPROC
199
200 /*
201 * Return to user mode is not as complex as all this looks,
202 * but we want the default path for a system call return to
203 * go as quickly as possible which is why some of this is
204 * less clear than it otherwise should be.
205 */
206
207 # userspace resumption stub bypassing syscall exit tracing
208 ALIGN
209 RING0_PTREGS_FRAME
210 ret_from_exception:
211 preempt_stop
212 ret_from_intr:
213 GET_THREAD_INFO(%ebp)
214 movl EFLAGS(%esp), %eax # mix EFLAGS and CS
215 movb CS(%esp), %al
216 testl $(VM_MASK | 3), %eax
217 jz resume_kernel
218 ENTRY(resume_userspace)
219 cli # make sure we don't miss an interrupt
220 # setting need_resched or sigpending
221 # between sampling and the iret
222 movl TI_flags(%ebp), %ecx
223 andl $_TIF_WORK_MASK, %ecx # is there any work to be done on
224 # int/exception return?
225 jne work_pending
226 jmp restore_all
227
228 #ifdef CONFIG_PREEMPT
229 ENTRY(resume_kernel)
230 cli
231 cmpl $0,TI_preempt_count(%ebp) # non-zero preempt_count ?
232 jnz restore_nocheck
233 need_resched:
234 movl TI_flags(%ebp), %ecx # need_resched set ?
235 testb $_TIF_NEED_RESCHED, %cl
236 jz restore_all
237 testl $IF_MASK,EFLAGS(%esp) # interrupts off (exception path) ?
238 jz restore_all
239 call preempt_schedule_irq
240 jmp need_resched
241 #endif
242 CFI_ENDPROC
243
244 /* SYSENTER_RETURN points to after the "sysenter" instruction in
245 the vsyscall page. See vsyscall-sysentry.S, which defines the symbol. */
246
247 # sysenter call handler stub
248 ENTRY(sysenter_entry)
249 CFI_STARTPROC simple
250 CFI_DEF_CFA esp, 0
251 CFI_REGISTER esp, ebp
252 movl TSS_sysenter_esp0(%esp),%esp
253 sysenter_past_esp:
254 sti
255 pushl $(__USER_DS)
256 CFI_ADJUST_CFA_OFFSET 4
257 /*CFI_REL_OFFSET ss, 0*/
258 pushl %ebp
259 CFI_ADJUST_CFA_OFFSET 4
260 CFI_REL_OFFSET esp, 0
261 pushfl
262 CFI_ADJUST_CFA_OFFSET 4
263 pushl $(__USER_CS)
264 CFI_ADJUST_CFA_OFFSET 4
265 /*CFI_REL_OFFSET cs, 0*/
266 pushl $SYSENTER_RETURN
267 CFI_ADJUST_CFA_OFFSET 4
268 CFI_REL_OFFSET eip, 0
269
270 /*
271 * Load the potential sixth argument from user stack.
272 * Careful about security.
273 */
274 cmpl $__PAGE_OFFSET-3,%ebp
275 jae syscall_fault
276 1: movl (%ebp),%ebp
277 .section __ex_table,"a"
278 .align 4
279 .long 1b,syscall_fault
280 .previous
281
282 pushl %eax
283 CFI_ADJUST_CFA_OFFSET 4
284 SAVE_ALL
285 GET_THREAD_INFO(%ebp)
286
287 /* Note, _TIF_SECCOMP is bit number 8, and so it needs testw and not testb */
288 testw $(_TIF_SYSCALL_EMU|_TIF_SYSCALL_TRACE|_TIF_SECCOMP|_TIF_SYSCALL_AUDIT),TI_flags(%ebp)
289 jnz syscall_trace_entry
290 cmpl $(nr_syscalls), %eax
291 jae syscall_badsys
292 call *sys_call_table(,%eax,4)
293 movl %eax,EAX(%esp)
294 cli
295 movl TI_flags(%ebp), %ecx
296 testw $_TIF_ALLWORK_MASK, %cx
297 jne syscall_exit_work
298 /* if something modifies registers it must also disable sysexit */
299 movl EIP(%esp), %edx
300 movl OLDESP(%esp), %ecx
301 xorl %ebp,%ebp
302 sti
303 sysexit
304 CFI_ENDPROC
305
306
307 # system call handler stub
308 ENTRY(system_call)
309 RING0_INT_FRAME # can't unwind into user space anyway
310 pushl %eax # save orig_eax
311 CFI_ADJUST_CFA_OFFSET 4
312 SAVE_ALL
313 GET_THREAD_INFO(%ebp)
314 testl $TF_MASK,EFLAGS(%esp)
315 jz no_singlestep
316 orl $_TIF_SINGLESTEP,TI_flags(%ebp)
317 no_singlestep:
318 # system call tracing in operation / emulation
319 /* Note, _TIF_SECCOMP is bit number 8, and so it needs testw and not testb */
320 testw $(_TIF_SYSCALL_EMU|_TIF_SYSCALL_TRACE|_TIF_SECCOMP|_TIF_SYSCALL_AUDIT),TI_flags(%ebp)
321 jnz syscall_trace_entry
322 cmpl $(nr_syscalls), %eax
323 jae syscall_badsys
324 syscall_call:
325 call *sys_call_table(,%eax,4)
326 movl %eax,EAX(%esp) # store the return value
327 syscall_exit:
328 cli # make sure we don't miss an interrupt
329 # setting need_resched or sigpending
330 # between sampling and the iret
331 movl TI_flags(%ebp), %ecx
332 testw $_TIF_ALLWORK_MASK, %cx # current->work
333 jne syscall_exit_work
334
335 restore_all:
336 movl EFLAGS(%esp), %eax # mix EFLAGS, SS and CS
337 # Warning: OLDSS(%esp) contains the wrong/random values if we
338 # are returning to the kernel.
339 # See comments in process.c:copy_thread() for details.
340 movb OLDSS(%esp), %ah
341 movb CS(%esp), %al
342 andl $(VM_MASK | (4 << 8) | 3), %eax
343 cmpl $((4 << 8) | 3), %eax
344 CFI_REMEMBER_STATE
345 je ldt_ss # returning to user-space with LDT SS
346 restore_nocheck:
347 RESTORE_REGS
348 addl $4, %esp
349 CFI_ADJUST_CFA_OFFSET -4
350 1: iret
351 .section .fixup,"ax"
352 iret_exc:
353 sti
354 pushl $0 # no error code
355 pushl $do_iret_error
356 jmp error_code
357 .previous
358 .section __ex_table,"a"
359 .align 4
360 .long 1b,iret_exc
361 .previous
362
363 CFI_RESTORE_STATE
364 ldt_ss:
365 larl OLDSS(%esp), %eax
366 jnz restore_nocheck
367 testl $0x00400000, %eax # returning to 32bit stack?
368 jnz restore_nocheck # allright, normal return
369 /* If returning to userspace with 16bit stack,
370 * try to fix the higher word of ESP, as the CPU
371 * won't restore it.
372 * This is an "official" bug of all the x86-compatible
373 * CPUs, which we can try to work around to make
374 * dosemu and wine happy. */
375 subl $8, %esp # reserve space for switch16 pointer
376 CFI_ADJUST_CFA_OFFSET 8
377 cli
378 movl %esp, %eax
379 /* Set up the 16bit stack frame with switch32 pointer on top,
380 * and a switch16 pointer on top of the current frame. */
381 call setup_x86_bogus_stack
382 CFI_ADJUST_CFA_OFFSET -8 # frame has moved
383 RESTORE_REGS
384 lss 20+4(%esp), %esp # switch to 16bit stack
385 1: iret
386 .section __ex_table,"a"
387 .align 4
388 .long 1b,iret_exc
389 .previous
390 CFI_ENDPROC
391
392 # perform work that needs to be done immediately before resumption
393 ALIGN
394 RING0_PTREGS_FRAME # can't unwind into user space anyway
395 work_pending:
396 testb $_TIF_NEED_RESCHED, %cl
397 jz work_notifysig
398 work_resched:
399 call schedule
400 cli # make sure we don't miss an interrupt
401 # setting need_resched or sigpending
402 # between sampling and the iret
403 movl TI_flags(%ebp), %ecx
404 andl $_TIF_WORK_MASK, %ecx # is there any work to be done other
405 # than syscall tracing?
406 jz restore_all
407 testb $_TIF_NEED_RESCHED, %cl
408 jnz work_resched
409
410 work_notifysig: # deal with pending signals and
411 # notify-resume requests
412 testl $VM_MASK, EFLAGS(%esp)
413 movl %esp, %eax
414 jne work_notifysig_v86 # returning to kernel-space or
415 # vm86-space
416 xorl %edx, %edx
417 call do_notify_resume
418 jmp resume_userspace
419
420 ALIGN
421 work_notifysig_v86:
422 #ifdef CONFIG_VM86
423 pushl %ecx # save ti_flags for do_notify_resume
424 CFI_ADJUST_CFA_OFFSET 4
425 call save_v86_state # %eax contains pt_regs pointer
426 popl %ecx
427 CFI_ADJUST_CFA_OFFSET -4
428 movl %eax, %esp
429 xorl %edx, %edx
430 call do_notify_resume
431 jmp resume_userspace
432 #endif
433
434 # perform syscall exit tracing
435 ALIGN
436 syscall_trace_entry:
437 movl $-ENOSYS,EAX(%esp)
438 movl %esp, %eax
439 xorl %edx,%edx
440 call do_syscall_trace
441 cmpl $0, %eax
442 jne resume_userspace # ret != 0 -> running under PTRACE_SYSEMU,
443 # so must skip actual syscall
444 movl ORIG_EAX(%esp), %eax
445 cmpl $(nr_syscalls), %eax
446 jnae syscall_call
447 jmp syscall_exit
448
449 # perform syscall exit tracing
450 ALIGN
451 syscall_exit_work:
452 testb $(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT|_TIF_SINGLESTEP), %cl
453 jz work_pending
454 sti # could let do_syscall_trace() call
455 # schedule() instead
456 movl %esp, %eax
457 movl $1, %edx
458 call do_syscall_trace
459 jmp resume_userspace
460 CFI_ENDPROC
461
462 RING0_INT_FRAME # can't unwind into user space anyway
463 syscall_fault:
464 pushl %eax # save orig_eax
465 CFI_ADJUST_CFA_OFFSET 4
466 SAVE_ALL
467 GET_THREAD_INFO(%ebp)
468 movl $-EFAULT,EAX(%esp)
469 jmp resume_userspace
470
471 syscall_badsys:
472 movl $-ENOSYS,EAX(%esp)
473 jmp resume_userspace
474 CFI_ENDPROC
475
476 #define FIXUP_ESPFIX_STACK \
477 movl %esp, %eax; \
478 /* switch to 32bit stack using the pointer on top of 16bit stack */ \
479 lss %ss:CPU_16BIT_STACK_SIZE-8, %esp; \
480 /* copy data from 16bit stack to 32bit stack */ \
481 call fixup_x86_bogus_stack; \
482 /* put ESP to the proper location */ \
483 movl %eax, %esp;
484 #define UNWIND_ESPFIX_STACK \
485 pushl %eax; \
486 CFI_ADJUST_CFA_OFFSET 4; \
487 movl %ss, %eax; \
488 /* see if on 16bit stack */ \
489 cmpw $__ESPFIX_SS, %ax; \
490 je 28f; \
491 27: popl %eax; \
492 CFI_ADJUST_CFA_OFFSET -4; \
493 .section .fixup,"ax"; \
494 28: movl $__KERNEL_DS, %eax; \
495 movl %eax, %ds; \
496 movl %eax, %es; \
497 /* switch to 32bit stack */ \
498 FIXUP_ESPFIX_STACK; \
499 jmp 27b; \
500 .previous
501
502 /*
503 * Build the entry stubs and pointer table with
504 * some assembler magic.
505 */
506 .data
507 ENTRY(interrupt)
508 .text
509
510 vector=0
511 ENTRY(irq_entries_start)
512 RING0_INT_FRAME
513 .rept NR_IRQS
514 ALIGN
515 .if vector
516 CFI_ADJUST_CFA_OFFSET -4
517 .endif
518 1: pushl $~(vector)
519 CFI_ADJUST_CFA_OFFSET 4
520 jmp common_interrupt
521 .data
522 .long 1b
523 .text
524 vector=vector+1
525 .endr
526
527 ALIGN
528 common_interrupt:
529 SAVE_ALL
530 movl %esp,%eax
531 call do_IRQ
532 jmp ret_from_intr
533 CFI_ENDPROC
534
535 #define BUILD_INTERRUPT(name, nr) \
536 ENTRY(name) \
537 RING0_INT_FRAME; \
538 pushl $~(nr); \
539 CFI_ADJUST_CFA_OFFSET 4; \
540 SAVE_ALL; \
541 movl %esp,%eax; \
542 call smp_/**/name; \
543 jmp ret_from_intr; \
544 CFI_ENDPROC
545
546 /* The include is where all of the SMP etc. interrupts come from */
547 #include "entry_arch.h"
548
549 ENTRY(divide_error)
550 RING0_INT_FRAME
551 pushl $0 # no error code
552 CFI_ADJUST_CFA_OFFSET 4
553 pushl $do_divide_error
554 CFI_ADJUST_CFA_OFFSET 4
555 ALIGN
556 error_code:
557 pushl %ds
558 CFI_ADJUST_CFA_OFFSET 4
559 /*CFI_REL_OFFSET ds, 0*/
560 pushl %eax
561 CFI_ADJUST_CFA_OFFSET 4
562 CFI_REL_OFFSET eax, 0
563 xorl %eax, %eax
564 pushl %ebp
565 CFI_ADJUST_CFA_OFFSET 4
566 CFI_REL_OFFSET ebp, 0
567 pushl %edi
568 CFI_ADJUST_CFA_OFFSET 4
569 CFI_REL_OFFSET edi, 0
570 pushl %esi
571 CFI_ADJUST_CFA_OFFSET 4
572 CFI_REL_OFFSET esi, 0
573 pushl %edx
574 CFI_ADJUST_CFA_OFFSET 4
575 CFI_REL_OFFSET edx, 0
576 decl %eax # eax = -1
577 pushl %ecx
578 CFI_ADJUST_CFA_OFFSET 4
579 CFI_REL_OFFSET ecx, 0
580 pushl %ebx
581 CFI_ADJUST_CFA_OFFSET 4
582 CFI_REL_OFFSET ebx, 0
583 cld
584 pushl %es
585 CFI_ADJUST_CFA_OFFSET 4
586 /*CFI_REL_OFFSET es, 0*/
587 UNWIND_ESPFIX_STACK
588 popl %ecx
589 CFI_ADJUST_CFA_OFFSET -4
590 /*CFI_REGISTER es, ecx*/
591 movl ES(%esp), %edi # get the function address
592 movl ORIG_EAX(%esp), %edx # get the error code
593 movl %eax, ORIG_EAX(%esp)
594 movl %ecx, ES(%esp)
595 /*CFI_REL_OFFSET es, ES*/
596 movl $(__USER_DS), %ecx
597 movl %ecx, %ds
598 movl %ecx, %es
599 movl %esp,%eax # pt_regs pointer
600 call *%edi
601 jmp ret_from_exception
602 CFI_ENDPROC
603
604 ENTRY(coprocessor_error)
605 RING0_INT_FRAME
606 pushl $0
607 CFI_ADJUST_CFA_OFFSET 4
608 pushl $do_coprocessor_error
609 CFI_ADJUST_CFA_OFFSET 4
610 jmp error_code
611 CFI_ENDPROC
612
613 ENTRY(simd_coprocessor_error)
614 RING0_INT_FRAME
615 pushl $0
616 CFI_ADJUST_CFA_OFFSET 4
617 pushl $do_simd_coprocessor_error
618 CFI_ADJUST_CFA_OFFSET 4
619 jmp error_code
620 CFI_ENDPROC
621
622 ENTRY(device_not_available)
623 RING0_INT_FRAME
624 pushl $-1 # mark this as an int
625 CFI_ADJUST_CFA_OFFSET 4
626 SAVE_ALL
627 movl %cr0, %eax
628 testl $0x4, %eax # EM (math emulation bit)
629 jne device_not_available_emulate
630 preempt_stop
631 call math_state_restore
632 jmp ret_from_exception
633 device_not_available_emulate:
634 pushl $0 # temporary storage for ORIG_EIP
635 CFI_ADJUST_CFA_OFFSET 4
636 call math_emulate
637 addl $4, %esp
638 CFI_ADJUST_CFA_OFFSET -4
639 jmp ret_from_exception
640 CFI_ENDPROC
641
642 /*
643 * Debug traps and NMI can happen at the one SYSENTER instruction
644 * that sets up the real kernel stack. Check here, since we can't
645 * allow the wrong stack to be used.
646 *
647 * "TSS_sysenter_esp0+12" is because the NMI/debug handler will have
648 * already pushed 3 words if it hits on the sysenter instruction:
649 * eflags, cs and eip.
650 *
651 * We just load the right stack, and push the three (known) values
652 * by hand onto the new stack - while updating the return eip past
653 * the instruction that would have done it for sysenter.
654 */
655 #define FIX_STACK(offset, ok, label) \
656 cmpw $__KERNEL_CS,4(%esp); \
657 jne ok; \
658 label: \
659 movl TSS_sysenter_esp0+offset(%esp),%esp; \
660 pushfl; \
661 pushl $__KERNEL_CS; \
662 pushl $sysenter_past_esp
663
664 KPROBE_ENTRY(debug)
665 RING0_INT_FRAME
666 cmpl $sysenter_entry,(%esp)
667 jne debug_stack_correct
668 FIX_STACK(12, debug_stack_correct, debug_esp_fix_insn)
669 debug_stack_correct:
670 pushl $-1 # mark this as an int
671 CFI_ADJUST_CFA_OFFSET 4
672 SAVE_ALL
673 xorl %edx,%edx # error code 0
674 movl %esp,%eax # pt_regs pointer
675 call do_debug
676 jmp ret_from_exception
677 CFI_ENDPROC
678 .previous .text
679 /*
680 * NMI is doubly nasty. It can happen _while_ we're handling
681 * a debug fault, and the debug fault hasn't yet been able to
682 * clear up the stack. So we first check whether we got an
683 * NMI on the sysenter entry path, but after that we need to
684 * check whether we got an NMI on the debug path where the debug
685 * fault happened on the sysenter path.
686 */
687 ENTRY(nmi)
688 RING0_INT_FRAME
689 pushl %eax
690 CFI_ADJUST_CFA_OFFSET 4
691 movl %ss, %eax
692 cmpw $__ESPFIX_SS, %ax
693 popl %eax
694 CFI_ADJUST_CFA_OFFSET -4
695 je nmi_16bit_stack
696 cmpl $sysenter_entry,(%esp)
697 je nmi_stack_fixup
698 pushl %eax
699 CFI_ADJUST_CFA_OFFSET 4
700 movl %esp,%eax
701 /* Do not access memory above the end of our stack page,
702 * it might not exist.
703 */
704 andl $(THREAD_SIZE-1),%eax
705 cmpl $(THREAD_SIZE-20),%eax
706 popl %eax
707 CFI_ADJUST_CFA_OFFSET -4
708 jae nmi_stack_correct
709 cmpl $sysenter_entry,12(%esp)
710 je nmi_debug_stack_check
711 nmi_stack_correct:
712 pushl %eax
713 CFI_ADJUST_CFA_OFFSET 4
714 SAVE_ALL
715 xorl %edx,%edx # zero error code
716 movl %esp,%eax # pt_regs pointer
717 call do_nmi
718 jmp restore_all
719 CFI_ENDPROC
720
721 nmi_stack_fixup:
722 FIX_STACK(12,nmi_stack_correct, 1)
723 jmp nmi_stack_correct
724 nmi_debug_stack_check:
725 cmpw $__KERNEL_CS,16(%esp)
726 jne nmi_stack_correct
727 cmpl $debug,(%esp)
728 jb nmi_stack_correct
729 cmpl $debug_esp_fix_insn,(%esp)
730 ja nmi_stack_correct
731 FIX_STACK(24,nmi_stack_correct, 1)
732 jmp nmi_stack_correct
733
734 nmi_16bit_stack:
735 RING0_INT_FRAME
736 /* create the pointer to lss back */
737 pushl %ss
738 CFI_ADJUST_CFA_OFFSET 4
739 pushl %esp
740 CFI_ADJUST_CFA_OFFSET 4
741 movzwl %sp, %esp
742 addw $4, (%esp)
743 /* copy the iret frame of 12 bytes */
744 .rept 3
745 pushl 16(%esp)
746 CFI_ADJUST_CFA_OFFSET 4
747 .endr
748 pushl %eax
749 CFI_ADJUST_CFA_OFFSET 4
750 SAVE_ALL
751 FIXUP_ESPFIX_STACK # %eax == %esp
752 CFI_ADJUST_CFA_OFFSET -20 # the frame has now moved
753 xorl %edx,%edx # zero error code
754 call do_nmi
755 RESTORE_REGS
756 lss 12+4(%esp), %esp # back to 16bit stack
757 1: iret
758 CFI_ENDPROC
759 .section __ex_table,"a"
760 .align 4
761 .long 1b,iret_exc
762 .previous
763
764 KPROBE_ENTRY(int3)
765 RING0_INT_FRAME
766 pushl $-1 # mark this as an int
767 CFI_ADJUST_CFA_OFFSET 4
768 SAVE_ALL
769 xorl %edx,%edx # zero error code
770 movl %esp,%eax # pt_regs pointer
771 call do_int3
772 jmp ret_from_exception
773 CFI_ENDPROC
774 .previous .text
775
776 ENTRY(overflow)
777 RING0_INT_FRAME
778 pushl $0
779 CFI_ADJUST_CFA_OFFSET 4
780 pushl $do_overflow
781 CFI_ADJUST_CFA_OFFSET 4
782 jmp error_code
783 CFI_ENDPROC
784
785 ENTRY(bounds)
786 RING0_INT_FRAME
787 pushl $0
788 CFI_ADJUST_CFA_OFFSET 4
789 pushl $do_bounds
790 CFI_ADJUST_CFA_OFFSET 4
791 jmp error_code
792 CFI_ENDPROC
793
794 ENTRY(invalid_op)
795 RING0_INT_FRAME
796 pushl $0
797 CFI_ADJUST_CFA_OFFSET 4
798 pushl $do_invalid_op
799 CFI_ADJUST_CFA_OFFSET 4
800 jmp error_code
801 CFI_ENDPROC
802
803 ENTRY(coprocessor_segment_overrun)
804 RING0_INT_FRAME
805 pushl $0
806 CFI_ADJUST_CFA_OFFSET 4
807 pushl $do_coprocessor_segment_overrun
808 CFI_ADJUST_CFA_OFFSET 4
809 jmp error_code
810 CFI_ENDPROC
811
812 ENTRY(invalid_TSS)
813 RING0_EC_FRAME
814 pushl $do_invalid_TSS
815 CFI_ADJUST_CFA_OFFSET 4
816 jmp error_code
817 CFI_ENDPROC
818
819 ENTRY(segment_not_present)
820 RING0_EC_FRAME
821 pushl $do_segment_not_present
822 CFI_ADJUST_CFA_OFFSET 4
823 jmp error_code
824 CFI_ENDPROC
825
826 ENTRY(stack_segment)
827 RING0_EC_FRAME
828 pushl $do_stack_segment
829 CFI_ADJUST_CFA_OFFSET 4
830 jmp error_code
831 CFI_ENDPROC
832
833 KPROBE_ENTRY(general_protection)
834 RING0_EC_FRAME
835 pushl $do_general_protection
836 CFI_ADJUST_CFA_OFFSET 4
837 jmp error_code
838 CFI_ENDPROC
839 .previous .text
840
841 ENTRY(alignment_check)
842 RING0_EC_FRAME
843 pushl $do_alignment_check
844 CFI_ADJUST_CFA_OFFSET 4
845 jmp error_code
846 CFI_ENDPROC
847
848 KPROBE_ENTRY(page_fault)
849 RING0_EC_FRAME
850 pushl $do_page_fault
851 CFI_ADJUST_CFA_OFFSET 4
852 jmp error_code
853 CFI_ENDPROC
854 .previous .text
855
856 #ifdef CONFIG_X86_MCE
857 ENTRY(machine_check)
858 RING0_INT_FRAME
859 pushl $0
860 CFI_ADJUST_CFA_OFFSET 4
861 pushl machine_check_vector
862 CFI_ADJUST_CFA_OFFSET 4
863 jmp error_code
864 CFI_ENDPROC
865 #endif
866
867 ENTRY(spurious_interrupt_bug)
868 RING0_INT_FRAME
869 pushl $0
870 CFI_ADJUST_CFA_OFFSET 4
871 pushl $do_spurious_interrupt_bug
872 CFI_ADJUST_CFA_OFFSET 4
873 jmp error_code
874 CFI_ENDPROC
875
876 #ifdef CONFIG_STACK_UNWIND
877 ENTRY(arch_unwind_init_running)
878 CFI_STARTPROC
879 movl 4(%esp), %edx
880 movl (%esp), %ecx
881 leal 4(%esp), %eax
882 movl %ebx, EBX(%edx)
883 xorl %ebx, %ebx
884 movl %ebx, ECX(%edx)
885 movl %ebx, EDX(%edx)
886 movl %esi, ESI(%edx)
887 movl %edi, EDI(%edx)
888 movl %ebp, EBP(%edx)
889 movl %ebx, EAX(%edx)
890 movl $__USER_DS, DS(%edx)
891 movl $__USER_DS, ES(%edx)
892 movl %ebx, ORIG_EAX(%edx)
893 movl %ecx, EIP(%edx)
894 movl 12(%esp), %ecx
895 movl $__KERNEL_CS, CS(%edx)
896 movl %ebx, EFLAGS(%edx)
897 movl %eax, OLDESP(%edx)
898 movl 8(%esp), %eax
899 movl %ecx, 8(%esp)
900 movl EBX(%edx), %ebx
901 movl $__KERNEL_DS, OLDSS(%edx)
902 jmpl *%eax
903 CFI_ENDPROC
904 ENDPROC(arch_unwind_init_running)
905 #endif
906
907 .section .rodata,"a"
908 #include "syscall_table.S"
909
910 syscall_table_size=(.-sys_call_table)
Linux kernel - Deliverables
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