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Commit | Line | Data |
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1da177e4 | 1 | /* |
1da177e4 LT |
2 | * |
3 | * Copyright (C) 1991, 1992 Linus Torvalds | |
4 | */ | |
5 | ||
6 | /* | |
7 | * entry.S contains the system-call and fault low-level handling routines. | |
8 | * This also contains the timer-interrupt handler, as well as all interrupts | |
9 | * and faults that can result in a task-switch. | |
10 | * | |
11 | * NOTE: This code handles signal-recognition, which happens every time | |
12 | * after a timer-interrupt and after each system call. | |
13 | * | |
14 | * I changed all the .align's to 4 (16 byte alignment), as that's faster | |
15 | * on a 486. | |
16 | * | |
889f21ce | 17 | * Stack layout in 'syscall_exit': |
1da177e4 LT |
18 | * ptrace needs to have all regs on the stack. |
19 | * if the order here is changed, it needs to be | |
20 | * updated in fork.c:copy_process, signal.c:do_signal, | |
21 | * ptrace.c and ptrace.h | |
22 | * | |
23 | * 0(%esp) - %ebx | |
24 | * 4(%esp) - %ecx | |
25 | * 8(%esp) - %edx | |
26 | * C(%esp) - %esi | |
27 | * 10(%esp) - %edi | |
28 | * 14(%esp) - %ebp | |
29 | * 18(%esp) - %eax | |
30 | * 1C(%esp) - %ds | |
31 | * 20(%esp) - %es | |
464d1a78 | 32 | * 24(%esp) - %fs |
f95d47ca JF |
33 | * 28(%esp) - orig_eax |
34 | * 2C(%esp) - %eip | |
35 | * 30(%esp) - %cs | |
36 | * 34(%esp) - %eflags | |
37 | * 38(%esp) - %oldesp | |
38 | * 3C(%esp) - %oldss | |
1da177e4 LT |
39 | * |
40 | * "current" is in register %ebx during any slow entries. | |
41 | */ | |
42 | ||
1da177e4 LT |
43 | #include <linux/linkage.h> |
44 | #include <asm/thread_info.h> | |
55f327fa | 45 | #include <asm/irqflags.h> |
1da177e4 LT |
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> | |
be44d2aa | 51 | #include <asm/percpu.h> |
fe7cacc1 | 52 | #include <asm/dwarf2.h> |
ab68ed98 | 53 | #include <asm/processor-flags.h> |
395a59d0 | 54 | #include <asm/ftrace.h> |
9b7dc567 | 55 | #include <asm/irq_vectors.h> |
1da177e4 | 56 | |
af0575bb RM |
57 | /* Avoid __ASSEMBLER__'ifying <linux/audit.h> just for this. */ |
58 | #include <linux/elf-em.h> | |
59 | #define AUDIT_ARCH_I386 (EM_386|__AUDIT_ARCH_LE) | |
60 | #define __AUDIT_ARCH_LE 0x40000000 | |
61 | ||
62 | #ifndef CONFIG_AUDITSYSCALL | |
63 | #define sysenter_audit syscall_trace_entry | |
64 | #define sysexit_audit syscall_exit_work | |
65 | #endif | |
66 | ||
139ec7c4 RR |
67 | /* |
68 | * We use macros for low-level operations which need to be overridden | |
69 | * for paravirtualization. The following will never clobber any registers: | |
70 | * INTERRUPT_RETURN (aka. "iret") | |
71 | * GET_CR0_INTO_EAX (aka. "movl %cr0, %eax") | |
d75cd22f | 72 | * ENABLE_INTERRUPTS_SYSEXIT (aka "sti; sysexit"). |
139ec7c4 RR |
73 | * |
74 | * For DISABLE_INTERRUPTS/ENABLE_INTERRUPTS (aka "cli"/"sti"), you must | |
75 | * specify what registers can be overwritten (CLBR_NONE, CLBR_EAX/EDX/ECX/ANY). | |
76 | * Allowing a register to be clobbered can shrink the paravirt replacement | |
77 | * enough to patch inline, increasing performance. | |
78 | */ | |
79 | ||
1da177e4 LT |
80 | #define nr_syscalls ((syscall_table_size)/4) |
81 | ||
1da177e4 | 82 | #ifdef CONFIG_PREEMPT |
139ec7c4 | 83 | #define preempt_stop(clobbers) DISABLE_INTERRUPTS(clobbers); TRACE_IRQS_OFF |
1da177e4 | 84 | #else |
139ec7c4 | 85 | #define preempt_stop(clobbers) |
1da177e4 LT |
86 | #define resume_kernel restore_nocheck |
87 | #endif | |
88 | ||
55f327fa IM |
89 | .macro TRACE_IRQS_IRET |
90 | #ifdef CONFIG_TRACE_IRQFLAGS | |
ab68ed98 | 91 | testl $X86_EFLAGS_IF,PT_EFLAGS(%esp) # interrupts off? |
55f327fa IM |
92 | jz 1f |
93 | TRACE_IRQS_ON | |
94 | 1: | |
95 | #endif | |
96 | .endm | |
97 | ||
4031ff38 AG |
98 | #ifdef CONFIG_VM86 |
99 | #define resume_userspace_sig check_userspace | |
100 | #else | |
101 | #define resume_userspace_sig resume_userspace | |
102 | #endif | |
103 | ||
1da177e4 LT |
104 | #define SAVE_ALL \ |
105 | cld; \ | |
464d1a78 | 106 | pushl %fs; \ |
f95d47ca | 107 | CFI_ADJUST_CFA_OFFSET 4;\ |
464d1a78 | 108 | /*CFI_REL_OFFSET fs, 0;*/\ |
1da177e4 | 109 | pushl %es; \ |
fe7cacc1 JB |
110 | CFI_ADJUST_CFA_OFFSET 4;\ |
111 | /*CFI_REL_OFFSET es, 0;*/\ | |
1da177e4 | 112 | pushl %ds; \ |
fe7cacc1 JB |
113 | CFI_ADJUST_CFA_OFFSET 4;\ |
114 | /*CFI_REL_OFFSET ds, 0;*/\ | |
1da177e4 | 115 | pushl %eax; \ |
fe7cacc1 JB |
116 | CFI_ADJUST_CFA_OFFSET 4;\ |
117 | CFI_REL_OFFSET eax, 0;\ | |
1da177e4 | 118 | pushl %ebp; \ |
fe7cacc1 JB |
119 | CFI_ADJUST_CFA_OFFSET 4;\ |
120 | CFI_REL_OFFSET ebp, 0;\ | |
1da177e4 | 121 | pushl %edi; \ |
fe7cacc1 JB |
122 | CFI_ADJUST_CFA_OFFSET 4;\ |
123 | CFI_REL_OFFSET edi, 0;\ | |
1da177e4 | 124 | pushl %esi; \ |
fe7cacc1 JB |
125 | CFI_ADJUST_CFA_OFFSET 4;\ |
126 | CFI_REL_OFFSET esi, 0;\ | |
1da177e4 | 127 | pushl %edx; \ |
fe7cacc1 JB |
128 | CFI_ADJUST_CFA_OFFSET 4;\ |
129 | CFI_REL_OFFSET edx, 0;\ | |
1da177e4 | 130 | pushl %ecx; \ |
fe7cacc1 JB |
131 | CFI_ADJUST_CFA_OFFSET 4;\ |
132 | CFI_REL_OFFSET ecx, 0;\ | |
1da177e4 | 133 | pushl %ebx; \ |
fe7cacc1 JB |
134 | CFI_ADJUST_CFA_OFFSET 4;\ |
135 | CFI_REL_OFFSET ebx, 0;\ | |
1da177e4 LT |
136 | movl $(__USER_DS), %edx; \ |
137 | movl %edx, %ds; \ | |
f95d47ca | 138 | movl %edx, %es; \ |
7c3576d2 | 139 | movl $(__KERNEL_PERCPU), %edx; \ |
464d1a78 | 140 | movl %edx, %fs |
1da177e4 LT |
141 | |
142 | #define RESTORE_INT_REGS \ | |
143 | popl %ebx; \ | |
fe7cacc1 JB |
144 | CFI_ADJUST_CFA_OFFSET -4;\ |
145 | CFI_RESTORE ebx;\ | |
1da177e4 | 146 | popl %ecx; \ |
fe7cacc1 JB |
147 | CFI_ADJUST_CFA_OFFSET -4;\ |
148 | CFI_RESTORE ecx;\ | |
1da177e4 | 149 | popl %edx; \ |
fe7cacc1 JB |
150 | CFI_ADJUST_CFA_OFFSET -4;\ |
151 | CFI_RESTORE edx;\ | |
1da177e4 | 152 | popl %esi; \ |
fe7cacc1 JB |
153 | CFI_ADJUST_CFA_OFFSET -4;\ |
154 | CFI_RESTORE esi;\ | |
1da177e4 | 155 | popl %edi; \ |
fe7cacc1 JB |
156 | CFI_ADJUST_CFA_OFFSET -4;\ |
157 | CFI_RESTORE edi;\ | |
1da177e4 | 158 | popl %ebp; \ |
fe7cacc1 JB |
159 | CFI_ADJUST_CFA_OFFSET -4;\ |
160 | CFI_RESTORE ebp;\ | |
161 | popl %eax; \ | |
162 | CFI_ADJUST_CFA_OFFSET -4;\ | |
163 | CFI_RESTORE eax | |
1da177e4 LT |
164 | |
165 | #define RESTORE_REGS \ | |
166 | RESTORE_INT_REGS; \ | |
167 | 1: popl %ds; \ | |
fe7cacc1 JB |
168 | CFI_ADJUST_CFA_OFFSET -4;\ |
169 | /*CFI_RESTORE ds;*/\ | |
1da177e4 | 170 | 2: popl %es; \ |
fe7cacc1 JB |
171 | CFI_ADJUST_CFA_OFFSET -4;\ |
172 | /*CFI_RESTORE es;*/\ | |
464d1a78 | 173 | 3: popl %fs; \ |
f95d47ca | 174 | CFI_ADJUST_CFA_OFFSET -4;\ |
464d1a78 | 175 | /*CFI_RESTORE fs;*/\ |
f95d47ca | 176 | .pushsection .fixup,"ax"; \ |
1da177e4 | 177 | 4: movl $0,(%esp); \ |
f95d47ca JF |
178 | jmp 1b; \ |
179 | 5: movl $0,(%esp); \ | |
1da177e4 | 180 | jmp 2b; \ |
f95d47ca JF |
181 | 6: movl $0,(%esp); \ |
182 | jmp 3b; \ | |
1da177e4 LT |
183 | .section __ex_table,"a";\ |
184 | .align 4; \ | |
f95d47ca JF |
185 | .long 1b,4b; \ |
186 | .long 2b,5b; \ | |
187 | .long 3b,6b; \ | |
188 | .popsection | |
1da177e4 | 189 | |
fe7cacc1 JB |
190 | #define RING0_INT_FRAME \ |
191 | CFI_STARTPROC simple;\ | |
adf14236 | 192 | CFI_SIGNAL_FRAME;\ |
fe7cacc1 JB |
193 | CFI_DEF_CFA esp, 3*4;\ |
194 | /*CFI_OFFSET cs, -2*4;*/\ | |
195 | CFI_OFFSET eip, -3*4 | |
196 | ||
197 | #define RING0_EC_FRAME \ | |
198 | CFI_STARTPROC simple;\ | |
adf14236 | 199 | CFI_SIGNAL_FRAME;\ |
fe7cacc1 JB |
200 | CFI_DEF_CFA esp, 4*4;\ |
201 | /*CFI_OFFSET cs, -2*4;*/\ | |
202 | CFI_OFFSET eip, -3*4 | |
203 | ||
204 | #define RING0_PTREGS_FRAME \ | |
205 | CFI_STARTPROC simple;\ | |
adf14236 | 206 | CFI_SIGNAL_FRAME;\ |
eb5b7b9d JF |
207 | CFI_DEF_CFA esp, PT_OLDESP-PT_EBX;\ |
208 | /*CFI_OFFSET cs, PT_CS-PT_OLDESP;*/\ | |
209 | CFI_OFFSET eip, PT_EIP-PT_OLDESP;\ | |
210 | /*CFI_OFFSET es, PT_ES-PT_OLDESP;*/\ | |
211 | /*CFI_OFFSET ds, PT_DS-PT_OLDESP;*/\ | |
212 | CFI_OFFSET eax, PT_EAX-PT_OLDESP;\ | |
213 | CFI_OFFSET ebp, PT_EBP-PT_OLDESP;\ | |
214 | CFI_OFFSET edi, PT_EDI-PT_OLDESP;\ | |
215 | CFI_OFFSET esi, PT_ESI-PT_OLDESP;\ | |
216 | CFI_OFFSET edx, PT_EDX-PT_OLDESP;\ | |
217 | CFI_OFFSET ecx, PT_ECX-PT_OLDESP;\ | |
218 | CFI_OFFSET ebx, PT_EBX-PT_OLDESP | |
1da177e4 LT |
219 | |
220 | ENTRY(ret_from_fork) | |
fe7cacc1 | 221 | CFI_STARTPROC |
1da177e4 | 222 | pushl %eax |
25d7dfda | 223 | CFI_ADJUST_CFA_OFFSET 4 |
1da177e4 LT |
224 | call schedule_tail |
225 | GET_THREAD_INFO(%ebp) | |
226 | popl %eax | |
fe7cacc1 | 227 | CFI_ADJUST_CFA_OFFSET -4 |
47a5c6fa LT |
228 | pushl $0x0202 # Reset kernel eflags |
229 | CFI_ADJUST_CFA_OFFSET 4 | |
230 | popfl | |
231 | CFI_ADJUST_CFA_OFFSET -4 | |
1da177e4 | 232 | jmp syscall_exit |
fe7cacc1 | 233 | CFI_ENDPROC |
47a55cd7 | 234 | END(ret_from_fork) |
1da177e4 LT |
235 | |
236 | /* | |
237 | * Return to user mode is not as complex as all this looks, | |
238 | * but we want the default path for a system call return to | |
239 | * go as quickly as possible which is why some of this is | |
240 | * less clear than it otherwise should be. | |
241 | */ | |
242 | ||
243 | # userspace resumption stub bypassing syscall exit tracing | |
244 | ALIGN | |
fe7cacc1 | 245 | RING0_PTREGS_FRAME |
1da177e4 | 246 | ret_from_exception: |
139ec7c4 | 247 | preempt_stop(CLBR_ANY) |
1da177e4 LT |
248 | ret_from_intr: |
249 | GET_THREAD_INFO(%ebp) | |
4031ff38 | 250 | check_userspace: |
eb5b7b9d JF |
251 | movl PT_EFLAGS(%esp), %eax # mix EFLAGS and CS |
252 | movb PT_CS(%esp), %al | |
ab68ed98 | 253 | andl $(X86_EFLAGS_VM | SEGMENT_RPL_MASK), %eax |
78be3706 RR |
254 | cmpl $USER_RPL, %eax |
255 | jb resume_kernel # not returning to v8086 or userspace | |
f95d47ca | 256 | |
1da177e4 | 257 | ENTRY(resume_userspace) |
c7e872e7 | 258 | LOCKDEP_SYS_EXIT |
139ec7c4 | 259 | DISABLE_INTERRUPTS(CLBR_ANY) # make sure we don't miss an interrupt |
1da177e4 LT |
260 | # setting need_resched or sigpending |
261 | # between sampling and the iret | |
e32e58a9 | 262 | TRACE_IRQS_OFF |
1da177e4 LT |
263 | movl TI_flags(%ebp), %ecx |
264 | andl $_TIF_WORK_MASK, %ecx # is there any work to be done on | |
265 | # int/exception return? | |
266 | jne work_pending | |
267 | jmp restore_all | |
47a55cd7 | 268 | END(ret_from_exception) |
1da177e4 LT |
269 | |
270 | #ifdef CONFIG_PREEMPT | |
271 | ENTRY(resume_kernel) | |
139ec7c4 | 272 | DISABLE_INTERRUPTS(CLBR_ANY) |
1da177e4 LT |
273 | cmpl $0,TI_preempt_count(%ebp) # non-zero preempt_count ? |
274 | jnz restore_nocheck | |
275 | need_resched: | |
276 | movl TI_flags(%ebp), %ecx # need_resched set ? | |
277 | testb $_TIF_NEED_RESCHED, %cl | |
278 | jz restore_all | |
ab68ed98 | 279 | testl $X86_EFLAGS_IF,PT_EFLAGS(%esp) # interrupts off (exception path) ? |
1da177e4 LT |
280 | jz restore_all |
281 | call preempt_schedule_irq | |
282 | jmp need_resched | |
47a55cd7 | 283 | END(resume_kernel) |
1da177e4 | 284 | #endif |
fe7cacc1 | 285 | CFI_ENDPROC |
1da177e4 LT |
286 | |
287 | /* SYSENTER_RETURN points to after the "sysenter" instruction in | |
288 | the vsyscall page. See vsyscall-sysentry.S, which defines the symbol. */ | |
289 | ||
290 | # sysenter call handler stub | |
0aa97fb2 | 291 | ENTRY(ia32_sysenter_target) |
fe7cacc1 | 292 | CFI_STARTPROC simple |
adf14236 | 293 | CFI_SIGNAL_FRAME |
fe7cacc1 JB |
294 | CFI_DEF_CFA esp, 0 |
295 | CFI_REGISTER esp, ebp | |
faca6227 | 296 | movl TSS_sysenter_sp0(%esp),%esp |
1da177e4 | 297 | sysenter_past_esp: |
55f327fa | 298 | /* |
d93c870b JF |
299 | * Interrupts are disabled here, but we can't trace it until |
300 | * enough kernel state to call TRACE_IRQS_OFF can be called - but | |
301 | * we immediately enable interrupts at that point anyway. | |
55f327fa | 302 | */ |
1da177e4 | 303 | pushl $(__USER_DS) |
fe7cacc1 JB |
304 | CFI_ADJUST_CFA_OFFSET 4 |
305 | /*CFI_REL_OFFSET ss, 0*/ | |
1da177e4 | 306 | pushl %ebp |
fe7cacc1 JB |
307 | CFI_ADJUST_CFA_OFFSET 4 |
308 | CFI_REL_OFFSET esp, 0 | |
1da177e4 | 309 | pushfl |
d93c870b | 310 | orl $X86_EFLAGS_IF, (%esp) |
fe7cacc1 | 311 | CFI_ADJUST_CFA_OFFSET 4 |
1da177e4 | 312 | pushl $(__USER_CS) |
fe7cacc1 JB |
313 | CFI_ADJUST_CFA_OFFSET 4 |
314 | /*CFI_REL_OFFSET cs, 0*/ | |
e6e5494c IM |
315 | /* |
316 | * Push current_thread_info()->sysenter_return to the stack. | |
317 | * A tiny bit of offset fixup is necessary - 4*4 means the 4 words | |
318 | * pushed above; +8 corresponds to copy_thread's esp0 setting. | |
319 | */ | |
320 | pushl (TI_sysenter_return-THREAD_SIZE+8+4*4)(%esp) | |
fe7cacc1 JB |
321 | CFI_ADJUST_CFA_OFFSET 4 |
322 | CFI_REL_OFFSET eip, 0 | |
1da177e4 | 323 | |
d93c870b JF |
324 | pushl %eax |
325 | CFI_ADJUST_CFA_OFFSET 4 | |
326 | SAVE_ALL | |
327 | ENABLE_INTERRUPTS(CLBR_NONE) | |
328 | ||
1da177e4 LT |
329 | /* |
330 | * Load the potential sixth argument from user stack. | |
331 | * Careful about security. | |
332 | */ | |
333 | cmpl $__PAGE_OFFSET-3,%ebp | |
334 | jae syscall_fault | |
335 | 1: movl (%ebp),%ebp | |
d93c870b | 336 | movl %ebp,PT_EBP(%esp) |
1da177e4 LT |
337 | .section __ex_table,"a" |
338 | .align 4 | |
339 | .long 1b,syscall_fault | |
340 | .previous | |
341 | ||
1da177e4 LT |
342 | GET_THREAD_INFO(%ebp) |
343 | ||
344 | /* Note, _TIF_SECCOMP is bit number 8, and so it needs testw and not testb */ | |
d4d67150 | 345 | testw $_TIF_WORK_SYSCALL_ENTRY,TI_flags(%ebp) |
af0575bb RM |
346 | jnz sysenter_audit |
347 | sysenter_do_call: | |
1da177e4 LT |
348 | cmpl $(nr_syscalls), %eax |
349 | jae syscall_badsys | |
350 | call *sys_call_table(,%eax,4) | |
eb5b7b9d | 351 | movl %eax,PT_EAX(%esp) |
c7e872e7 | 352 | LOCKDEP_SYS_EXIT |
42c24fa2 | 353 | DISABLE_INTERRUPTS(CLBR_ANY) |
55f327fa | 354 | TRACE_IRQS_OFF |
1da177e4 LT |
355 | movl TI_flags(%ebp), %ecx |
356 | testw $_TIF_ALLWORK_MASK, %cx | |
af0575bb RM |
357 | jne sysexit_audit |
358 | sysenter_exit: | |
1da177e4 | 359 | /* if something modifies registers it must also disable sysexit */ |
eb5b7b9d JF |
360 | movl PT_EIP(%esp), %edx |
361 | movl PT_OLDESP(%esp), %ecx | |
1da177e4 | 362 | xorl %ebp,%ebp |
55f327fa | 363 | TRACE_IRQS_ON |
464d1a78 | 364 | 1: mov PT_FS(%esp), %fs |
d75cd22f | 365 | ENABLE_INTERRUPTS_SYSEXIT |
af0575bb RM |
366 | |
367 | #ifdef CONFIG_AUDITSYSCALL | |
368 | sysenter_audit: | |
369 | testw $(_TIF_WORK_SYSCALL_ENTRY & ~_TIF_SYSCALL_AUDIT),TI_flags(%ebp) | |
370 | jnz syscall_trace_entry | |
371 | addl $4,%esp | |
372 | CFI_ADJUST_CFA_OFFSET -4 | |
373 | /* %esi already in 8(%esp) 6th arg: 4th syscall arg */ | |
374 | /* %edx already in 4(%esp) 5th arg: 3rd syscall arg */ | |
375 | /* %ecx already in 0(%esp) 4th arg: 2nd syscall arg */ | |
376 | movl %ebx,%ecx /* 3rd arg: 1st syscall arg */ | |
377 | movl %eax,%edx /* 2nd arg: syscall number */ | |
378 | movl $AUDIT_ARCH_I386,%eax /* 1st arg: audit arch */ | |
379 | call audit_syscall_entry | |
380 | pushl %ebx | |
381 | CFI_ADJUST_CFA_OFFSET 4 | |
382 | movl PT_EAX(%esp),%eax /* reload syscall number */ | |
383 | jmp sysenter_do_call | |
384 | ||
385 | sysexit_audit: | |
386 | testw $(_TIF_ALLWORK_MASK & ~_TIF_SYSCALL_AUDIT), %cx | |
387 | jne syscall_exit_work | |
388 | TRACE_IRQS_ON | |
389 | ENABLE_INTERRUPTS(CLBR_ANY) | |
390 | movl %eax,%edx /* second arg, syscall return value */ | |
391 | cmpl $0,%eax /* is it < 0? */ | |
392 | setl %al /* 1 if so, 0 if not */ | |
393 | movzbl %al,%eax /* zero-extend that */ | |
394 | inc %eax /* first arg, 0->1(AUDITSC_SUCCESS), 1->2(AUDITSC_FAILURE) */ | |
395 | call audit_syscall_exit | |
396 | DISABLE_INTERRUPTS(CLBR_ANY) | |
397 | TRACE_IRQS_OFF | |
398 | movl TI_flags(%ebp), %ecx | |
399 | testw $(_TIF_ALLWORK_MASK & ~_TIF_SYSCALL_AUDIT), %cx | |
400 | jne syscall_exit_work | |
401 | movl PT_EAX(%esp),%eax /* reload syscall return value */ | |
402 | jmp sysenter_exit | |
403 | #endif | |
404 | ||
fe7cacc1 | 405 | CFI_ENDPROC |
f95d47ca | 406 | .pushsection .fixup,"ax" |
464d1a78 | 407 | 2: movl $0,PT_FS(%esp) |
f95d47ca JF |
408 | jmp 1b |
409 | .section __ex_table,"a" | |
410 | .align 4 | |
411 | .long 1b,2b | |
412 | .popsection | |
0aa97fb2 | 413 | ENDPROC(ia32_sysenter_target) |
1da177e4 LT |
414 | |
415 | # system call handler stub | |
416 | ENTRY(system_call) | |
fe7cacc1 | 417 | RING0_INT_FRAME # can't unwind into user space anyway |
1da177e4 | 418 | pushl %eax # save orig_eax |
fe7cacc1 | 419 | CFI_ADJUST_CFA_OFFSET 4 |
1da177e4 LT |
420 | SAVE_ALL |
421 | GET_THREAD_INFO(%ebp) | |
ed75e8d5 | 422 | # system call tracing in operation / emulation |
1da177e4 | 423 | /* Note, _TIF_SECCOMP is bit number 8, and so it needs testw and not testb */ |
d4d67150 | 424 | testw $_TIF_WORK_SYSCALL_ENTRY,TI_flags(%ebp) |
1da177e4 LT |
425 | jnz syscall_trace_entry |
426 | cmpl $(nr_syscalls), %eax | |
427 | jae syscall_badsys | |
428 | syscall_call: | |
429 | call *sys_call_table(,%eax,4) | |
eb5b7b9d | 430 | movl %eax,PT_EAX(%esp) # store the return value |
1da177e4 | 431 | syscall_exit: |
c7e872e7 | 432 | LOCKDEP_SYS_EXIT |
139ec7c4 | 433 | DISABLE_INTERRUPTS(CLBR_ANY) # make sure we don't miss an interrupt |
1da177e4 LT |
434 | # setting need_resched or sigpending |
435 | # between sampling and the iret | |
55f327fa | 436 | TRACE_IRQS_OFF |
1da177e4 LT |
437 | movl TI_flags(%ebp), %ecx |
438 | testw $_TIF_ALLWORK_MASK, %cx # current->work | |
439 | jne syscall_exit_work | |
440 | ||
441 | restore_all: | |
eb5b7b9d JF |
442 | movl PT_EFLAGS(%esp), %eax # mix EFLAGS, SS and CS |
443 | # Warning: PT_OLDSS(%esp) contains the wrong/random values if we | |
5df24082 SS |
444 | # are returning to the kernel. |
445 | # See comments in process.c:copy_thread() for details. | |
eb5b7b9d JF |
446 | movb PT_OLDSS(%esp), %ah |
447 | movb PT_CS(%esp), %al | |
ab68ed98 | 448 | andl $(X86_EFLAGS_VM | (SEGMENT_TI_MASK << 8) | SEGMENT_RPL_MASK), %eax |
78be3706 | 449 | cmpl $((SEGMENT_LDT << 8) | USER_RPL), %eax |
fe7cacc1 | 450 | CFI_REMEMBER_STATE |
1da177e4 LT |
451 | je ldt_ss # returning to user-space with LDT SS |
452 | restore_nocheck: | |
55f327fa IM |
453 | TRACE_IRQS_IRET |
454 | restore_nocheck_notrace: | |
1da177e4 | 455 | RESTORE_REGS |
f95d47ca | 456 | addl $4, %esp # skip orig_eax/error_code |
fe7cacc1 | 457 | CFI_ADJUST_CFA_OFFSET -4 |
f7f3d791 | 458 | irq_return: |
3701d863 | 459 | INTERRUPT_RETURN |
1da177e4 | 460 | .section .fixup,"ax" |
90e9f536 | 461 | ENTRY(iret_exc) |
a879cbbb LT |
462 | pushl $0 # no error code |
463 | pushl $do_iret_error | |
464 | jmp error_code | |
1da177e4 LT |
465 | .previous |
466 | .section __ex_table,"a" | |
467 | .align 4 | |
3701d863 | 468 | .long irq_return,iret_exc |
1da177e4 LT |
469 | .previous |
470 | ||
fe7cacc1 | 471 | CFI_RESTORE_STATE |
1da177e4 | 472 | ldt_ss: |
eb5b7b9d | 473 | larl PT_OLDSS(%esp), %eax |
1da177e4 LT |
474 | jnz restore_nocheck |
475 | testl $0x00400000, %eax # returning to 32bit stack? | |
476 | jnz restore_nocheck # allright, normal return | |
d3561b7f RR |
477 | |
478 | #ifdef CONFIG_PARAVIRT | |
479 | /* | |
480 | * The kernel can't run on a non-flat stack if paravirt mode | |
481 | * is active. Rather than try to fixup the high bits of | |
482 | * ESP, bypass this code entirely. This may break DOSemu | |
483 | * and/or Wine support in a paravirt VM, although the option | |
484 | * is still available to implement the setting of the high | |
485 | * 16-bits in the INTERRUPT_RETURN paravirt-op. | |
486 | */ | |
93b1eab3 | 487 | cmpl $0, pv_info+PARAVIRT_enabled |
d3561b7f RR |
488 | jne restore_nocheck |
489 | #endif | |
490 | ||
1da177e4 LT |
491 | /* If returning to userspace with 16bit stack, |
492 | * try to fix the higher word of ESP, as the CPU | |
493 | * won't restore it. | |
494 | * This is an "official" bug of all the x86-compatible | |
495 | * CPUs, which we can try to work around to make | |
496 | * dosemu and wine happy. */ | |
eb5b7b9d | 497 | movl PT_OLDESP(%esp), %eax |
be44d2aa SS |
498 | movl %esp, %edx |
499 | call patch_espfix_desc | |
500 | pushl $__ESPFIX_SS | |
501 | CFI_ADJUST_CFA_OFFSET 4 | |
502 | pushl %eax | |
503 | CFI_ADJUST_CFA_OFFSET 4 | |
139ec7c4 | 504 | DISABLE_INTERRUPTS(CLBR_EAX) |
55f327fa | 505 | TRACE_IRQS_OFF |
be44d2aa SS |
506 | lss (%esp), %esp |
507 | CFI_ADJUST_CFA_OFFSET -8 | |
508 | jmp restore_nocheck | |
fe7cacc1 | 509 | CFI_ENDPROC |
47a55cd7 | 510 | ENDPROC(system_call) |
1da177e4 LT |
511 | |
512 | # perform work that needs to be done immediately before resumption | |
513 | ALIGN | |
fe7cacc1 | 514 | RING0_PTREGS_FRAME # can't unwind into user space anyway |
1da177e4 LT |
515 | work_pending: |
516 | testb $_TIF_NEED_RESCHED, %cl | |
517 | jz work_notifysig | |
518 | work_resched: | |
519 | call schedule | |
c7e872e7 | 520 | LOCKDEP_SYS_EXIT |
139ec7c4 | 521 | DISABLE_INTERRUPTS(CLBR_ANY) # make sure we don't miss an interrupt |
1da177e4 LT |
522 | # setting need_resched or sigpending |
523 | # between sampling and the iret | |
55f327fa | 524 | TRACE_IRQS_OFF |
1da177e4 LT |
525 | movl TI_flags(%ebp), %ecx |
526 | andl $_TIF_WORK_MASK, %ecx # is there any work to be done other | |
527 | # than syscall tracing? | |
528 | jz restore_all | |
529 | testb $_TIF_NEED_RESCHED, %cl | |
530 | jnz work_resched | |
531 | ||
532 | work_notifysig: # deal with pending signals and | |
533 | # notify-resume requests | |
74b47a78 | 534 | #ifdef CONFIG_VM86 |
ab68ed98 | 535 | testl $X86_EFLAGS_VM, PT_EFLAGS(%esp) |
1da177e4 LT |
536 | movl %esp, %eax |
537 | jne work_notifysig_v86 # returning to kernel-space or | |
538 | # vm86-space | |
539 | xorl %edx, %edx | |
540 | call do_notify_resume | |
4031ff38 | 541 | jmp resume_userspace_sig |
1da177e4 LT |
542 | |
543 | ALIGN | |
544 | work_notifysig_v86: | |
545 | pushl %ecx # save ti_flags for do_notify_resume | |
fe7cacc1 | 546 | CFI_ADJUST_CFA_OFFSET 4 |
1da177e4 LT |
547 | call save_v86_state # %eax contains pt_regs pointer |
548 | popl %ecx | |
fe7cacc1 | 549 | CFI_ADJUST_CFA_OFFSET -4 |
1da177e4 | 550 | movl %eax, %esp |
74b47a78 JK |
551 | #else |
552 | movl %esp, %eax | |
553 | #endif | |
1da177e4 LT |
554 | xorl %edx, %edx |
555 | call do_notify_resume | |
4031ff38 | 556 | jmp resume_userspace_sig |
47a55cd7 | 557 | END(work_pending) |
1da177e4 LT |
558 | |
559 | # perform syscall exit tracing | |
560 | ALIGN | |
561 | syscall_trace_entry: | |
eb5b7b9d | 562 | movl $-ENOSYS,PT_EAX(%esp) |
1da177e4 | 563 | movl %esp, %eax |
d4d67150 RM |
564 | call syscall_trace_enter |
565 | /* What it returned is what we'll actually use. */ | |
1da177e4 LT |
566 | cmpl $(nr_syscalls), %eax |
567 | jnae syscall_call | |
568 | jmp syscall_exit | |
47a55cd7 | 569 | END(syscall_trace_entry) |
1da177e4 LT |
570 | |
571 | # perform syscall exit tracing | |
572 | ALIGN | |
573 | syscall_exit_work: | |
d4d67150 | 574 | testb $_TIF_WORK_SYSCALL_EXIT, %cl |
1da177e4 | 575 | jz work_pending |
55f327fa | 576 | TRACE_IRQS_ON |
d4d67150 | 577 | ENABLE_INTERRUPTS(CLBR_ANY) # could let syscall_trace_leave() call |
1da177e4 LT |
578 | # schedule() instead |
579 | movl %esp, %eax | |
d4d67150 | 580 | call syscall_trace_leave |
1da177e4 | 581 | jmp resume_userspace |
47a55cd7 | 582 | END(syscall_exit_work) |
fe7cacc1 | 583 | CFI_ENDPROC |
1da177e4 | 584 | |
fe7cacc1 | 585 | RING0_INT_FRAME # can't unwind into user space anyway |
1da177e4 | 586 | syscall_fault: |
1da177e4 | 587 | GET_THREAD_INFO(%ebp) |
eb5b7b9d | 588 | movl $-EFAULT,PT_EAX(%esp) |
1da177e4 | 589 | jmp resume_userspace |
47a55cd7 | 590 | END(syscall_fault) |
1da177e4 | 591 | |
1da177e4 | 592 | syscall_badsys: |
eb5b7b9d | 593 | movl $-ENOSYS,PT_EAX(%esp) |
1da177e4 | 594 | jmp resume_userspace |
47a55cd7 | 595 | END(syscall_badsys) |
fe7cacc1 | 596 | CFI_ENDPROC |
1da177e4 LT |
597 | |
598 | #define FIXUP_ESPFIX_STACK \ | |
be44d2aa | 599 | /* since we are on a wrong stack, we cant make it a C code :( */ \ |
7a61d35d | 600 | PER_CPU(gdt_page, %ebx); \ |
be44d2aa SS |
601 | GET_DESC_BASE(GDT_ENTRY_ESPFIX_SS, %ebx, %eax, %ax, %al, %ah); \ |
602 | addl %esp, %eax; \ | |
603 | pushl $__KERNEL_DS; \ | |
604 | CFI_ADJUST_CFA_OFFSET 4; \ | |
1da177e4 | 605 | pushl %eax; \ |
fe7cacc1 | 606 | CFI_ADJUST_CFA_OFFSET 4; \ |
be44d2aa SS |
607 | lss (%esp), %esp; \ |
608 | CFI_ADJUST_CFA_OFFSET -8; | |
609 | #define UNWIND_ESPFIX_STACK \ | |
1da177e4 | 610 | movl %ss, %eax; \ |
be44d2aa | 611 | /* see if on espfix stack */ \ |
1da177e4 | 612 | cmpw $__ESPFIX_SS, %ax; \ |
be44d2aa SS |
613 | jne 27f; \ |
614 | movl $__KERNEL_DS, %eax; \ | |
fe7cacc1 JB |
615 | movl %eax, %ds; \ |
616 | movl %eax, %es; \ | |
be44d2aa | 617 | /* switch to normal stack */ \ |
fe7cacc1 | 618 | FIXUP_ESPFIX_STACK; \ |
be44d2aa | 619 | 27:; |
1da177e4 LT |
620 | |
621 | /* | |
b7c6244f PA |
622 | * Build the entry stubs and pointer table with some assembler magic. |
623 | * We pack 7 stubs into a single 32-byte chunk, which will fit in a | |
624 | * single cache line on all modern x86 implementations. | |
1da177e4 | 625 | */ |
4687518c | 626 | .section .init.rodata,"a" |
1da177e4 LT |
627 | ENTRY(interrupt) |
628 | .text | |
b7c6244f PA |
629 | .p2align 5 |
630 | .p2align CONFIG_X86_L1_CACHE_SHIFT | |
1da177e4 | 631 | ENTRY(irq_entries_start) |
fe7cacc1 | 632 | RING0_INT_FRAME |
4687518c | 633 | vector=FIRST_EXTERNAL_VECTOR |
b7c6244f PA |
634 | .rept (NR_VECTORS-FIRST_EXTERNAL_VECTOR+6)/7 |
635 | .balign 32 | |
636 | .rept 7 | |
637 | .if vector < NR_VECTORS | |
8665596e | 638 | .if vector <> FIRST_EXTERNAL_VECTOR |
fe7cacc1 | 639 | CFI_ADJUST_CFA_OFFSET -4 |
b7c6244f PA |
640 | .endif |
641 | 1: pushl $(~vector+0x80) /* Note: always in signed byte range */ | |
fe7cacc1 | 642 | CFI_ADJUST_CFA_OFFSET 4 |
8665596e | 643 | .if ((vector-FIRST_EXTERNAL_VECTOR)%7) <> 6 |
b7c6244f PA |
644 | jmp 2f |
645 | .endif | |
646 | .previous | |
1da177e4 | 647 | .long 1b |
b7c6244f | 648 | .text |
1da177e4 | 649 | vector=vector+1 |
b7c6244f PA |
650 | .endif |
651 | .endr | |
652 | 2: jmp common_interrupt | |
1da177e4 | 653 | .endr |
47a55cd7 JB |
654 | END(irq_entries_start) |
655 | ||
656 | .previous | |
657 | END(interrupt) | |
658 | .previous | |
1da177e4 | 659 | |
55f327fa IM |
660 | /* |
661 | * the CPU automatically disables interrupts when executing an IRQ vector, | |
662 | * so IRQ-flags tracing has to follow that: | |
663 | */ | |
b7c6244f | 664 | .p2align CONFIG_X86_L1_CACHE_SHIFT |
1da177e4 | 665 | common_interrupt: |
b7c6244f | 666 | addl $-0x80,(%esp) /* Adjust vector into the [-256,-1] range */ |
1da177e4 | 667 | SAVE_ALL |
55f327fa | 668 | TRACE_IRQS_OFF |
1da177e4 LT |
669 | movl %esp,%eax |
670 | call do_IRQ | |
671 | jmp ret_from_intr | |
47a55cd7 | 672 | ENDPROC(common_interrupt) |
fe7cacc1 | 673 | CFI_ENDPROC |
1da177e4 LT |
674 | |
675 | #define BUILD_INTERRUPT(name, nr) \ | |
676 | ENTRY(name) \ | |
fe7cacc1 | 677 | RING0_INT_FRAME; \ |
19eadf98 | 678 | pushl $~(nr); \ |
fe7cacc1 JB |
679 | CFI_ADJUST_CFA_OFFSET 4; \ |
680 | SAVE_ALL; \ | |
55f327fa | 681 | TRACE_IRQS_OFF \ |
1da177e4 | 682 | movl %esp,%eax; \ |
f76c3923 | 683 | call smp_##name; \ |
55f327fa | 684 | jmp ret_from_intr; \ |
47a55cd7 JB |
685 | CFI_ENDPROC; \ |
686 | ENDPROC(name) | |
1da177e4 LT |
687 | |
688 | /* The include is where all of the SMP etc. interrupts come from */ | |
689 | #include "entry_arch.h" | |
690 | ||
1da177e4 | 691 | ENTRY(coprocessor_error) |
fe7cacc1 | 692 | RING0_INT_FRAME |
1da177e4 | 693 | pushl $0 |
fe7cacc1 | 694 | CFI_ADJUST_CFA_OFFSET 4 |
1da177e4 | 695 | pushl $do_coprocessor_error |
fe7cacc1 | 696 | CFI_ADJUST_CFA_OFFSET 4 |
1da177e4 | 697 | jmp error_code |
fe7cacc1 | 698 | CFI_ENDPROC |
47a55cd7 | 699 | END(coprocessor_error) |
1da177e4 LT |
700 | |
701 | ENTRY(simd_coprocessor_error) | |
fe7cacc1 | 702 | RING0_INT_FRAME |
1da177e4 | 703 | pushl $0 |
fe7cacc1 | 704 | CFI_ADJUST_CFA_OFFSET 4 |
1da177e4 | 705 | pushl $do_simd_coprocessor_error |
fe7cacc1 | 706 | CFI_ADJUST_CFA_OFFSET 4 |
1da177e4 | 707 | jmp error_code |
fe7cacc1 | 708 | CFI_ENDPROC |
47a55cd7 | 709 | END(simd_coprocessor_error) |
1da177e4 LT |
710 | |
711 | ENTRY(device_not_available) | |
fe7cacc1 | 712 | RING0_INT_FRAME |
1da177e4 | 713 | pushl $-1 # mark this as an int |
fe7cacc1 | 714 | CFI_ADJUST_CFA_OFFSET 4 |
7643e9b9 | 715 | pushl $do_device_not_available |
fe7cacc1 | 716 | CFI_ADJUST_CFA_OFFSET 4 |
7643e9b9 | 717 | jmp error_code |
fe7cacc1 | 718 | CFI_ENDPROC |
47a55cd7 | 719 | END(device_not_available) |
1da177e4 | 720 | |
d3561b7f RR |
721 | #ifdef CONFIG_PARAVIRT |
722 | ENTRY(native_iret) | |
3701d863 | 723 | iret |
d3561b7f RR |
724 | .section __ex_table,"a" |
725 | .align 4 | |
3701d863 | 726 | .long native_iret, iret_exc |
d3561b7f | 727 | .previous |
47a55cd7 | 728 | END(native_iret) |
d3561b7f | 729 | |
d75cd22f | 730 | ENTRY(native_irq_enable_sysexit) |
d3561b7f RR |
731 | sti |
732 | sysexit | |
d75cd22f | 733 | END(native_irq_enable_sysexit) |
d3561b7f RR |
734 | #endif |
735 | ||
1da177e4 | 736 | ENTRY(overflow) |
fe7cacc1 | 737 | RING0_INT_FRAME |
1da177e4 | 738 | pushl $0 |
fe7cacc1 | 739 | CFI_ADJUST_CFA_OFFSET 4 |
1da177e4 | 740 | pushl $do_overflow |
fe7cacc1 | 741 | CFI_ADJUST_CFA_OFFSET 4 |
1da177e4 | 742 | jmp error_code |
fe7cacc1 | 743 | CFI_ENDPROC |
47a55cd7 | 744 | END(overflow) |
1da177e4 LT |
745 | |
746 | ENTRY(bounds) | |
fe7cacc1 | 747 | RING0_INT_FRAME |
1da177e4 | 748 | pushl $0 |
fe7cacc1 | 749 | CFI_ADJUST_CFA_OFFSET 4 |
1da177e4 | 750 | pushl $do_bounds |
fe7cacc1 | 751 | CFI_ADJUST_CFA_OFFSET 4 |
1da177e4 | 752 | jmp error_code |
fe7cacc1 | 753 | CFI_ENDPROC |
47a55cd7 | 754 | END(bounds) |
1da177e4 LT |
755 | |
756 | ENTRY(invalid_op) | |
fe7cacc1 | 757 | RING0_INT_FRAME |
1da177e4 | 758 | pushl $0 |
fe7cacc1 | 759 | CFI_ADJUST_CFA_OFFSET 4 |
1da177e4 | 760 | pushl $do_invalid_op |
fe7cacc1 | 761 | CFI_ADJUST_CFA_OFFSET 4 |
1da177e4 | 762 | jmp error_code |
fe7cacc1 | 763 | CFI_ENDPROC |
47a55cd7 | 764 | END(invalid_op) |
1da177e4 LT |
765 | |
766 | ENTRY(coprocessor_segment_overrun) | |
fe7cacc1 | 767 | RING0_INT_FRAME |
1da177e4 | 768 | pushl $0 |
fe7cacc1 | 769 | CFI_ADJUST_CFA_OFFSET 4 |
1da177e4 | 770 | pushl $do_coprocessor_segment_overrun |
fe7cacc1 | 771 | CFI_ADJUST_CFA_OFFSET 4 |
1da177e4 | 772 | jmp error_code |
fe7cacc1 | 773 | CFI_ENDPROC |
47a55cd7 | 774 | END(coprocessor_segment_overrun) |
1da177e4 LT |
775 | |
776 | ENTRY(invalid_TSS) | |
fe7cacc1 | 777 | RING0_EC_FRAME |
1da177e4 | 778 | pushl $do_invalid_TSS |
fe7cacc1 | 779 | CFI_ADJUST_CFA_OFFSET 4 |
1da177e4 | 780 | jmp error_code |
fe7cacc1 | 781 | CFI_ENDPROC |
47a55cd7 | 782 | END(invalid_TSS) |
1da177e4 LT |
783 | |
784 | ENTRY(segment_not_present) | |
fe7cacc1 | 785 | RING0_EC_FRAME |
1da177e4 | 786 | pushl $do_segment_not_present |
fe7cacc1 | 787 | CFI_ADJUST_CFA_OFFSET 4 |
1da177e4 | 788 | jmp error_code |
fe7cacc1 | 789 | CFI_ENDPROC |
47a55cd7 | 790 | END(segment_not_present) |
1da177e4 LT |
791 | |
792 | ENTRY(stack_segment) | |
fe7cacc1 | 793 | RING0_EC_FRAME |
1da177e4 | 794 | pushl $do_stack_segment |
fe7cacc1 | 795 | CFI_ADJUST_CFA_OFFSET 4 |
1da177e4 | 796 | jmp error_code |
fe7cacc1 | 797 | CFI_ENDPROC |
47a55cd7 | 798 | END(stack_segment) |
1da177e4 | 799 | |
1da177e4 | 800 | ENTRY(alignment_check) |
fe7cacc1 | 801 | RING0_EC_FRAME |
1da177e4 | 802 | pushl $do_alignment_check |
fe7cacc1 | 803 | CFI_ADJUST_CFA_OFFSET 4 |
1da177e4 | 804 | jmp error_code |
fe7cacc1 | 805 | CFI_ENDPROC |
47a55cd7 | 806 | END(alignment_check) |
1da177e4 | 807 | |
d28c4393 P |
808 | ENTRY(divide_error) |
809 | RING0_INT_FRAME | |
810 | pushl $0 # no error code | |
811 | CFI_ADJUST_CFA_OFFSET 4 | |
812 | pushl $do_divide_error | |
fe7cacc1 | 813 | CFI_ADJUST_CFA_OFFSET 4 |
1da177e4 | 814 | jmp error_code |
fe7cacc1 | 815 | CFI_ENDPROC |
47a55cd7 | 816 | END(divide_error) |
1da177e4 LT |
817 | |
818 | #ifdef CONFIG_X86_MCE | |
819 | ENTRY(machine_check) | |
fe7cacc1 | 820 | RING0_INT_FRAME |
1da177e4 | 821 | pushl $0 |
fe7cacc1 | 822 | CFI_ADJUST_CFA_OFFSET 4 |
d2f6f7ae | 823 | pushl machine_check_vector |
fe7cacc1 | 824 | CFI_ADJUST_CFA_OFFSET 4 |
1da177e4 | 825 | jmp error_code |
fe7cacc1 | 826 | CFI_ENDPROC |
47a55cd7 | 827 | END(machine_check) |
1da177e4 LT |
828 | #endif |
829 | ||
830 | ENTRY(spurious_interrupt_bug) | |
fe7cacc1 | 831 | RING0_INT_FRAME |
1da177e4 | 832 | pushl $0 |
fe7cacc1 | 833 | CFI_ADJUST_CFA_OFFSET 4 |
1da177e4 | 834 | pushl $do_spurious_interrupt_bug |
fe7cacc1 | 835 | CFI_ADJUST_CFA_OFFSET 4 |
1da177e4 | 836 | jmp error_code |
fe7cacc1 | 837 | CFI_ENDPROC |
47a55cd7 | 838 | END(spurious_interrupt_bug) |
1da177e4 | 839 | |
02ba1a32 AK |
840 | ENTRY(kernel_thread_helper) |
841 | pushl $0 # fake return address for unwinder | |
842 | CFI_STARTPROC | |
843 | movl %edx,%eax | |
844 | push %edx | |
845 | CFI_ADJUST_CFA_OFFSET 4 | |
846 | call *%ebx | |
847 | push %eax | |
848 | CFI_ADJUST_CFA_OFFSET 4 | |
849 | call do_exit | |
5f5db591 | 850 | ud2 # padding for call trace |
02ba1a32 AK |
851 | CFI_ENDPROC |
852 | ENDPROC(kernel_thread_helper) | |
853 | ||
5ead97c8 | 854 | #ifdef CONFIG_XEN |
e2a81baf JF |
855 | /* Xen doesn't set %esp to be precisely what the normal sysenter |
856 | entrypoint expects, so fix it up before using the normal path. */ | |
857 | ENTRY(xen_sysenter_target) | |
858 | RING0_INT_FRAME | |
859 | addl $5*4, %esp /* remove xen-provided frame */ | |
2ddf9b7b | 860 | CFI_ADJUST_CFA_OFFSET -5*4 |
e2a81baf | 861 | jmp sysenter_past_esp |
557d7d4e | 862 | CFI_ENDPROC |
e2a81baf | 863 | |
5ead97c8 JF |
864 | ENTRY(xen_hypervisor_callback) |
865 | CFI_STARTPROC | |
866 | pushl $0 | |
867 | CFI_ADJUST_CFA_OFFSET 4 | |
868 | SAVE_ALL | |
869 | TRACE_IRQS_OFF | |
9ec2b804 JF |
870 | |
871 | /* Check to see if we got the event in the critical | |
872 | region in xen_iret_direct, after we've reenabled | |
873 | events and checked for pending events. This simulates | |
874 | iret instruction's behaviour where it delivers a | |
875 | pending interrupt when enabling interrupts. */ | |
876 | movl PT_EIP(%esp),%eax | |
877 | cmpl $xen_iret_start_crit,%eax | |
878 | jb 1f | |
879 | cmpl $xen_iret_end_crit,%eax | |
880 | jae 1f | |
881 | ||
0f2c8769 | 882 | jmp xen_iret_crit_fixup |
e2a81baf | 883 | |
e2a81baf | 884 | ENTRY(xen_do_upcall) |
b77797fb | 885 | 1: mov %esp, %eax |
5ead97c8 JF |
886 | call xen_evtchn_do_upcall |
887 | jmp ret_from_intr | |
888 | CFI_ENDPROC | |
889 | ENDPROC(xen_hypervisor_callback) | |
890 | ||
891 | # Hypervisor uses this for application faults while it executes. | |
892 | # We get here for two reasons: | |
893 | # 1. Fault while reloading DS, ES, FS or GS | |
894 | # 2. Fault while executing IRET | |
895 | # Category 1 we fix up by reattempting the load, and zeroing the segment | |
896 | # register if the load fails. | |
897 | # Category 2 we fix up by jumping to do_iret_error. We cannot use the | |
898 | # normal Linux return path in this case because if we use the IRET hypercall | |
899 | # to pop the stack frame we end up in an infinite loop of failsafe callbacks. | |
900 | # We distinguish between categories by maintaining a status value in EAX. | |
901 | ENTRY(xen_failsafe_callback) | |
902 | CFI_STARTPROC | |
903 | pushl %eax | |
904 | CFI_ADJUST_CFA_OFFSET 4 | |
905 | movl $1,%eax | |
906 | 1: mov 4(%esp),%ds | |
907 | 2: mov 8(%esp),%es | |
908 | 3: mov 12(%esp),%fs | |
909 | 4: mov 16(%esp),%gs | |
910 | testl %eax,%eax | |
911 | popl %eax | |
912 | CFI_ADJUST_CFA_OFFSET -4 | |
913 | lea 16(%esp),%esp | |
914 | CFI_ADJUST_CFA_OFFSET -16 | |
915 | jz 5f | |
916 | addl $16,%esp | |
917 | jmp iret_exc # EAX != 0 => Category 2 (Bad IRET) | |
918 | 5: pushl $0 # EAX == 0 => Category 1 (Bad segment) | |
919 | CFI_ADJUST_CFA_OFFSET 4 | |
920 | SAVE_ALL | |
921 | jmp ret_from_exception | |
922 | CFI_ENDPROC | |
923 | ||
924 | .section .fixup,"ax" | |
925 | 6: xorl %eax,%eax | |
926 | movl %eax,4(%esp) | |
927 | jmp 1b | |
928 | 7: xorl %eax,%eax | |
929 | movl %eax,8(%esp) | |
930 | jmp 2b | |
931 | 8: xorl %eax,%eax | |
932 | movl %eax,12(%esp) | |
933 | jmp 3b | |
934 | 9: xorl %eax,%eax | |
935 | movl %eax,16(%esp) | |
936 | jmp 4b | |
937 | .previous | |
938 | .section __ex_table,"a" | |
939 | .align 4 | |
940 | .long 1b,6b | |
941 | .long 2b,7b | |
942 | .long 3b,8b | |
943 | .long 4b,9b | |
944 | .previous | |
945 | ENDPROC(xen_failsafe_callback) | |
946 | ||
947 | #endif /* CONFIG_XEN */ | |
948 | ||
606576ce | 949 | #ifdef CONFIG_FUNCTION_TRACER |
d61f82d0 SR |
950 | #ifdef CONFIG_DYNAMIC_FTRACE |
951 | ||
952 | ENTRY(mcount) | |
d61f82d0 SR |
953 | ret |
954 | END(mcount) | |
955 | ||
956 | ENTRY(ftrace_caller) | |
60a7ecf4 SR |
957 | cmpl $0, function_trace_stop |
958 | jne ftrace_stub | |
959 | ||
d61f82d0 SR |
960 | pushl %eax |
961 | pushl %ecx | |
962 | pushl %edx | |
963 | movl 0xc(%esp), %eax | |
964 | movl 0x4(%ebp), %edx | |
395a59d0 | 965 | subl $MCOUNT_INSN_SIZE, %eax |
d61f82d0 SR |
966 | |
967 | .globl ftrace_call | |
968 | ftrace_call: | |
969 | call ftrace_stub | |
970 | ||
971 | popl %edx | |
972 | popl %ecx | |
973 | popl %eax | |
5a45cfe1 SR |
974 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
975 | .globl ftrace_graph_call | |
976 | ftrace_graph_call: | |
977 | jmp ftrace_stub | |
978 | #endif | |
d61f82d0 SR |
979 | |
980 | .globl ftrace_stub | |
981 | ftrace_stub: | |
982 | ret | |
983 | END(ftrace_caller) | |
984 | ||
985 | #else /* ! CONFIG_DYNAMIC_FTRACE */ | |
986 | ||
16444a8a | 987 | ENTRY(mcount) |
60a7ecf4 SR |
988 | cmpl $0, function_trace_stop |
989 | jne ftrace_stub | |
990 | ||
16444a8a ACM |
991 | cmpl $ftrace_stub, ftrace_trace_function |
992 | jnz trace | |
fb52607a | 993 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
c2324b69 | 994 | cmpl $ftrace_stub, ftrace_graph_return |
fb52607a | 995 | jnz ftrace_graph_caller |
e49dc19c SR |
996 | |
997 | cmpl $ftrace_graph_entry_stub, ftrace_graph_entry | |
998 | jnz ftrace_graph_caller | |
caf4b323 | 999 | #endif |
16444a8a ACM |
1000 | .globl ftrace_stub |
1001 | ftrace_stub: | |
1002 | ret | |
1003 | ||
1004 | /* taken from glibc */ | |
1005 | trace: | |
1006 | pushl %eax | |
1007 | pushl %ecx | |
1008 | pushl %edx | |
1009 | movl 0xc(%esp), %eax | |
1010 | movl 0x4(%ebp), %edx | |
395a59d0 | 1011 | subl $MCOUNT_INSN_SIZE, %eax |
16444a8a | 1012 | |
d61f82d0 | 1013 | call *ftrace_trace_function |
16444a8a ACM |
1014 | |
1015 | popl %edx | |
1016 | popl %ecx | |
1017 | popl %eax | |
16444a8a ACM |
1018 | jmp ftrace_stub |
1019 | END(mcount) | |
d61f82d0 | 1020 | #endif /* CONFIG_DYNAMIC_FTRACE */ |
606576ce | 1021 | #endif /* CONFIG_FUNCTION_TRACER */ |
16444a8a | 1022 | |
fb52607a FW |
1023 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
1024 | ENTRY(ftrace_graph_caller) | |
e7d3737e FW |
1025 | cmpl $0, function_trace_stop |
1026 | jne ftrace_stub | |
1027 | ||
caf4b323 FW |
1028 | pushl %eax |
1029 | pushl %ecx | |
1030 | pushl %edx | |
1dc1c6ad | 1031 | movl 0xc(%esp), %edx |
caf4b323 | 1032 | lea 0x4(%ebp), %eax |
bb4304c7 | 1033 | subl $MCOUNT_INSN_SIZE, %edx |
caf4b323 | 1034 | call prepare_ftrace_return |
caf4b323 FW |
1035 | popl %edx |
1036 | popl %ecx | |
1037 | popl %eax | |
e7d3737e | 1038 | ret |
fb52607a | 1039 | END(ftrace_graph_caller) |
caf4b323 FW |
1040 | |
1041 | .globl return_to_handler | |
1042 | return_to_handler: | |
1043 | pushl $0 | |
1044 | pushl %eax | |
1045 | pushl %ecx | |
1046 | pushl %edx | |
1047 | call ftrace_return_to_handler | |
1048 | movl %eax, 0xc(%esp) | |
1049 | popl %edx | |
1050 | popl %ecx | |
1051 | popl %eax | |
1052 | ret | |
e7d3737e | 1053 | #endif |
16444a8a | 1054 | |
bb152f53 | 1055 | .section .rodata,"a" |
541054d9 | 1056 | #include "syscall_table_32.S" |
1da177e4 LT |
1057 | |
1058 | syscall_table_size=(.-sys_call_table) | |
d211af05 AH |
1059 | |
1060 | /* | |
1061 | * Some functions should be protected against kprobes | |
1062 | */ | |
1063 | .pushsection .kprobes.text, "ax" | |
1064 | ||
1065 | ENTRY(page_fault) | |
1066 | RING0_EC_FRAME | |
1067 | pushl $do_page_fault | |
1068 | CFI_ADJUST_CFA_OFFSET 4 | |
1069 | ALIGN | |
1070 | error_code: | |
1071 | /* the function address is in %fs's slot on the stack */ | |
1072 | pushl %es | |
1073 | CFI_ADJUST_CFA_OFFSET 4 | |
1074 | /*CFI_REL_OFFSET es, 0*/ | |
1075 | pushl %ds | |
1076 | CFI_ADJUST_CFA_OFFSET 4 | |
1077 | /*CFI_REL_OFFSET ds, 0*/ | |
1078 | pushl %eax | |
1079 | CFI_ADJUST_CFA_OFFSET 4 | |
1080 | CFI_REL_OFFSET eax, 0 | |
1081 | pushl %ebp | |
1082 | CFI_ADJUST_CFA_OFFSET 4 | |
1083 | CFI_REL_OFFSET ebp, 0 | |
1084 | pushl %edi | |
1085 | CFI_ADJUST_CFA_OFFSET 4 | |
1086 | CFI_REL_OFFSET edi, 0 | |
1087 | pushl %esi | |
1088 | CFI_ADJUST_CFA_OFFSET 4 | |
1089 | CFI_REL_OFFSET esi, 0 | |
1090 | pushl %edx | |
1091 | CFI_ADJUST_CFA_OFFSET 4 | |
1092 | CFI_REL_OFFSET edx, 0 | |
1093 | pushl %ecx | |
1094 | CFI_ADJUST_CFA_OFFSET 4 | |
1095 | CFI_REL_OFFSET ecx, 0 | |
1096 | pushl %ebx | |
1097 | CFI_ADJUST_CFA_OFFSET 4 | |
1098 | CFI_REL_OFFSET ebx, 0 | |
1099 | cld | |
1100 | pushl %fs | |
1101 | CFI_ADJUST_CFA_OFFSET 4 | |
1102 | /*CFI_REL_OFFSET fs, 0*/ | |
1103 | movl $(__KERNEL_PERCPU), %ecx | |
1104 | movl %ecx, %fs | |
1105 | UNWIND_ESPFIX_STACK | |
1106 | popl %ecx | |
1107 | CFI_ADJUST_CFA_OFFSET -4 | |
1108 | /*CFI_REGISTER es, ecx*/ | |
1109 | movl PT_FS(%esp), %edi # get the function address | |
1110 | movl PT_ORIG_EAX(%esp), %edx # get the error code | |
1111 | movl $-1, PT_ORIG_EAX(%esp) # no syscall to restart | |
1112 | mov %ecx, PT_FS(%esp) | |
1113 | /*CFI_REL_OFFSET fs, ES*/ | |
1114 | movl $(__USER_DS), %ecx | |
1115 | movl %ecx, %ds | |
1116 | movl %ecx, %es | |
1117 | TRACE_IRQS_OFF | |
1118 | movl %esp,%eax # pt_regs pointer | |
1119 | call *%edi | |
1120 | jmp ret_from_exception | |
1121 | CFI_ENDPROC | |
1122 | END(page_fault) | |
1123 | ||
1124 | /* | |
1125 | * Debug traps and NMI can happen at the one SYSENTER instruction | |
1126 | * that sets up the real kernel stack. Check here, since we can't | |
1127 | * allow the wrong stack to be used. | |
1128 | * | |
1129 | * "TSS_sysenter_sp0+12" is because the NMI/debug handler will have | |
1130 | * already pushed 3 words if it hits on the sysenter instruction: | |
1131 | * eflags, cs and eip. | |
1132 | * | |
1133 | * We just load the right stack, and push the three (known) values | |
1134 | * by hand onto the new stack - while updating the return eip past | |
1135 | * the instruction that would have done it for sysenter. | |
1136 | */ | |
1137 | #define FIX_STACK(offset, ok, label) \ | |
1138 | cmpw $__KERNEL_CS,4(%esp); \ | |
1139 | jne ok; \ | |
1140 | label: \ | |
1141 | movl TSS_sysenter_sp0+offset(%esp),%esp; \ | |
1142 | CFI_DEF_CFA esp, 0; \ | |
1143 | CFI_UNDEFINED eip; \ | |
1144 | pushfl; \ | |
1145 | CFI_ADJUST_CFA_OFFSET 4; \ | |
1146 | pushl $__KERNEL_CS; \ | |
1147 | CFI_ADJUST_CFA_OFFSET 4; \ | |
1148 | pushl $sysenter_past_esp; \ | |
1149 | CFI_ADJUST_CFA_OFFSET 4; \ | |
1150 | CFI_REL_OFFSET eip, 0 | |
1151 | ||
1152 | ENTRY(debug) | |
1153 | RING0_INT_FRAME | |
1154 | cmpl $ia32_sysenter_target,(%esp) | |
1155 | jne debug_stack_correct | |
1156 | FIX_STACK(12, debug_stack_correct, debug_esp_fix_insn) | |
1157 | debug_stack_correct: | |
1158 | pushl $-1 # mark this as an int | |
1159 | CFI_ADJUST_CFA_OFFSET 4 | |
1160 | SAVE_ALL | |
1161 | TRACE_IRQS_OFF | |
1162 | xorl %edx,%edx # error code 0 | |
1163 | movl %esp,%eax # pt_regs pointer | |
1164 | call do_debug | |
1165 | jmp ret_from_exception | |
1166 | CFI_ENDPROC | |
1167 | END(debug) | |
1168 | ||
1169 | /* | |
1170 | * NMI is doubly nasty. It can happen _while_ we're handling | |
1171 | * a debug fault, and the debug fault hasn't yet been able to | |
1172 | * clear up the stack. So we first check whether we got an | |
1173 | * NMI on the sysenter entry path, but after that we need to | |
1174 | * check whether we got an NMI on the debug path where the debug | |
1175 | * fault happened on the sysenter path. | |
1176 | */ | |
1177 | ENTRY(nmi) | |
1178 | RING0_INT_FRAME | |
1179 | pushl %eax | |
1180 | CFI_ADJUST_CFA_OFFSET 4 | |
1181 | movl %ss, %eax | |
1182 | cmpw $__ESPFIX_SS, %ax | |
1183 | popl %eax | |
1184 | CFI_ADJUST_CFA_OFFSET -4 | |
1185 | je nmi_espfix_stack | |
1186 | cmpl $ia32_sysenter_target,(%esp) | |
1187 | je nmi_stack_fixup | |
1188 | pushl %eax | |
1189 | CFI_ADJUST_CFA_OFFSET 4 | |
1190 | movl %esp,%eax | |
1191 | /* Do not access memory above the end of our stack page, | |
1192 | * it might not exist. | |
1193 | */ | |
1194 | andl $(THREAD_SIZE-1),%eax | |
1195 | cmpl $(THREAD_SIZE-20),%eax | |
1196 | popl %eax | |
1197 | CFI_ADJUST_CFA_OFFSET -4 | |
1198 | jae nmi_stack_correct | |
1199 | cmpl $ia32_sysenter_target,12(%esp) | |
1200 | je nmi_debug_stack_check | |
1201 | nmi_stack_correct: | |
1202 | /* We have a RING0_INT_FRAME here */ | |
1203 | pushl %eax | |
1204 | CFI_ADJUST_CFA_OFFSET 4 | |
1205 | SAVE_ALL | |
d211af05 AH |
1206 | xorl %edx,%edx # zero error code |
1207 | movl %esp,%eax # pt_regs pointer | |
1208 | call do_nmi | |
1209 | jmp restore_nocheck_notrace | |
1210 | CFI_ENDPROC | |
1211 | ||
1212 | nmi_stack_fixup: | |
1213 | RING0_INT_FRAME | |
1214 | FIX_STACK(12,nmi_stack_correct, 1) | |
1215 | jmp nmi_stack_correct | |
1216 | ||
1217 | nmi_debug_stack_check: | |
1218 | /* We have a RING0_INT_FRAME here */ | |
1219 | cmpw $__KERNEL_CS,16(%esp) | |
1220 | jne nmi_stack_correct | |
1221 | cmpl $debug,(%esp) | |
1222 | jb nmi_stack_correct | |
1223 | cmpl $debug_esp_fix_insn,(%esp) | |
1224 | ja nmi_stack_correct | |
1225 | FIX_STACK(24,nmi_stack_correct, 1) | |
1226 | jmp nmi_stack_correct | |
1227 | ||
1228 | nmi_espfix_stack: | |
1229 | /* We have a RING0_INT_FRAME here. | |
1230 | * | |
1231 | * create the pointer to lss back | |
1232 | */ | |
1233 | pushl %ss | |
1234 | CFI_ADJUST_CFA_OFFSET 4 | |
1235 | pushl %esp | |
1236 | CFI_ADJUST_CFA_OFFSET 4 | |
1237 | addw $4, (%esp) | |
1238 | /* copy the iret frame of 12 bytes */ | |
1239 | .rept 3 | |
1240 | pushl 16(%esp) | |
1241 | CFI_ADJUST_CFA_OFFSET 4 | |
1242 | .endr | |
1243 | pushl %eax | |
1244 | CFI_ADJUST_CFA_OFFSET 4 | |
1245 | SAVE_ALL | |
d211af05 AH |
1246 | FIXUP_ESPFIX_STACK # %eax == %esp |
1247 | xorl %edx,%edx # zero error code | |
1248 | call do_nmi | |
1249 | RESTORE_REGS | |
1250 | lss 12+4(%esp), %esp # back to espfix stack | |
1251 | CFI_ADJUST_CFA_OFFSET -24 | |
1252 | jmp irq_return | |
1253 | CFI_ENDPROC | |
1254 | END(nmi) | |
1255 | ||
1256 | ENTRY(int3) | |
1257 | RING0_INT_FRAME | |
1258 | pushl $-1 # mark this as an int | |
1259 | CFI_ADJUST_CFA_OFFSET 4 | |
1260 | SAVE_ALL | |
1261 | TRACE_IRQS_OFF | |
1262 | xorl %edx,%edx # zero error code | |
1263 | movl %esp,%eax # pt_regs pointer | |
1264 | call do_int3 | |
1265 | jmp ret_from_exception | |
1266 | CFI_ENDPROC | |
1267 | END(int3) | |
1268 | ||
1269 | ENTRY(general_protection) | |
1270 | RING0_EC_FRAME | |
1271 | pushl $do_general_protection | |
1272 | CFI_ADJUST_CFA_OFFSET 4 | |
1273 | jmp error_code | |
1274 | CFI_ENDPROC | |
1275 | END(general_protection) | |
1276 | ||
1277 | /* | |
1278 | * End of kprobes section | |
1279 | */ | |
1280 | .popsection |