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Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * linux/arch/x86_64/entry.S | |
3 | * | |
4 | * Copyright (C) 1991, 1992 Linus Torvalds | |
5 | * Copyright (C) 2000, 2001, 2002 Andi Kleen SuSE Labs | |
6 | * Copyright (C) 2000 Pavel Machek <pavel@suse.cz> | |
1da177e4 LT |
7 | */ |
8 | ||
9 | /* | |
10 | * entry.S contains the system-call and fault low-level handling routines. | |
11 | * | |
12 | * NOTE: This code handles signal-recognition, which happens every time | |
13 | * after an interrupt and after each system call. | |
14 | * | |
15 | * Normal syscalls and interrupts don't save a full stack frame, this is | |
16 | * only done for syscall tracing, signals or fork/exec et.al. | |
17 | * | |
18 | * A note on terminology: | |
19 | * - top of stack: Architecture defined interrupt frame from SS to RIP | |
20 | * at the top of the kernel process stack. | |
21 | * - partial stack frame: partially saved registers upto R11. | |
22 | * - full stack frame: Like partial stack frame, but all register saved. | |
2e91a17b AK |
23 | * |
24 | * Some macro usage: | |
25 | * - CFI macros are used to generate dwarf2 unwind information for better | |
26 | * backtraces. They don't change any code. | |
27 | * - SAVE_ALL/RESTORE_ALL - Save/restore all registers | |
28 | * - SAVE_ARGS/RESTORE_ARGS - Save/restore registers that C functions modify. | |
29 | * There are unfortunately lots of special cases where some registers | |
30 | * not touched. The macro is a big mess that should be cleaned up. | |
31 | * - SAVE_REST/RESTORE_REST - Handle the registers not saved by SAVE_ARGS. | |
32 | * Gives a full stack frame. | |
33 | * - ENTRY/END Define functions in the symbol table. | |
34 | * - FIXUP_TOP_OF_STACK/RESTORE_TOP_OF_STACK - Fix up the hardware stack | |
35 | * frame that is otherwise undefined after a SYSCALL | |
36 | * - TRACE_IRQ_* - Trace hard interrupt state for lock debugging. | |
37 | * - errorentry/paranoidentry/zeroentry - Define exception entry points. | |
1da177e4 LT |
38 | */ |
39 | ||
1da177e4 LT |
40 | #include <linux/linkage.h> |
41 | #include <asm/segment.h> | |
1da177e4 LT |
42 | #include <asm/cache.h> |
43 | #include <asm/errno.h> | |
44 | #include <asm/dwarf2.h> | |
45 | #include <asm/calling.h> | |
e2d5df93 | 46 | #include <asm/asm-offsets.h> |
1da177e4 LT |
47 | #include <asm/msr.h> |
48 | #include <asm/unistd.h> | |
49 | #include <asm/thread_info.h> | |
50 | #include <asm/hw_irq.h> | |
5f8efbb9 | 51 | #include <asm/page.h> |
2601e64d | 52 | #include <asm/irqflags.h> |
1da177e4 LT |
53 | |
54 | .code64 | |
55 | ||
dc37db4d | 56 | #ifndef CONFIG_PREEMPT |
1da177e4 LT |
57 | #define retint_kernel retint_restore_args |
58 | #endif | |
2601e64d IM |
59 | |
60 | ||
61 | .macro TRACE_IRQS_IRETQ offset=ARGOFFSET | |
62 | #ifdef CONFIG_TRACE_IRQFLAGS | |
63 | bt $9,EFLAGS-\offset(%rsp) /* interrupts off? */ | |
64 | jnc 1f | |
65 | TRACE_IRQS_ON | |
66 | 1: | |
67 | #endif | |
68 | .endm | |
69 | ||
1da177e4 LT |
70 | /* |
71 | * C code is not supposed to know about undefined top of stack. Every time | |
72 | * a C function with an pt_regs argument is called from the SYSCALL based | |
73 | * fast path FIXUP_TOP_OF_STACK is needed. | |
74 | * RESTORE_TOP_OF_STACK syncs the syscall state after any possible ptregs | |
75 | * manipulation. | |
76 | */ | |
77 | ||
78 | /* %rsp:at FRAMEEND */ | |
79 | .macro FIXUP_TOP_OF_STACK tmp | |
80 | movq %gs:pda_oldrsp,\tmp | |
81 | movq \tmp,RSP(%rsp) | |
82 | movq $__USER_DS,SS(%rsp) | |
83 | movq $__USER_CS,CS(%rsp) | |
84 | movq $-1,RCX(%rsp) | |
85 | movq R11(%rsp),\tmp /* get eflags */ | |
86 | movq \tmp,EFLAGS(%rsp) | |
87 | .endm | |
88 | ||
89 | .macro RESTORE_TOP_OF_STACK tmp,offset=0 | |
90 | movq RSP-\offset(%rsp),\tmp | |
91 | movq \tmp,%gs:pda_oldrsp | |
92 | movq EFLAGS-\offset(%rsp),\tmp | |
93 | movq \tmp,R11-\offset(%rsp) | |
94 | .endm | |
95 | ||
96 | .macro FAKE_STACK_FRAME child_rip | |
97 | /* push in order ss, rsp, eflags, cs, rip */ | |
3829ee6b | 98 | xorl %eax, %eax |
1da177e4 LT |
99 | pushq %rax /* ss */ |
100 | CFI_ADJUST_CFA_OFFSET 8 | |
7effaa88 | 101 | /*CFI_REL_OFFSET ss,0*/ |
1da177e4 LT |
102 | pushq %rax /* rsp */ |
103 | CFI_ADJUST_CFA_OFFSET 8 | |
7effaa88 | 104 | CFI_REL_OFFSET rsp,0 |
1da177e4 LT |
105 | pushq $(1<<9) /* eflags - interrupts on */ |
106 | CFI_ADJUST_CFA_OFFSET 8 | |
7effaa88 | 107 | /*CFI_REL_OFFSET rflags,0*/ |
1da177e4 LT |
108 | pushq $__KERNEL_CS /* cs */ |
109 | CFI_ADJUST_CFA_OFFSET 8 | |
7effaa88 | 110 | /*CFI_REL_OFFSET cs,0*/ |
1da177e4 LT |
111 | pushq \child_rip /* rip */ |
112 | CFI_ADJUST_CFA_OFFSET 8 | |
7effaa88 | 113 | CFI_REL_OFFSET rip,0 |
1da177e4 LT |
114 | pushq %rax /* orig rax */ |
115 | CFI_ADJUST_CFA_OFFSET 8 | |
116 | .endm | |
117 | ||
118 | .macro UNFAKE_STACK_FRAME | |
119 | addq $8*6, %rsp | |
120 | CFI_ADJUST_CFA_OFFSET -(6*8) | |
121 | .endm | |
122 | ||
7effaa88 JB |
123 | .macro CFI_DEFAULT_STACK start=1 |
124 | .if \start | |
125 | CFI_STARTPROC simple | |
adf14236 | 126 | CFI_SIGNAL_FRAME |
7effaa88 JB |
127 | CFI_DEF_CFA rsp,SS+8 |
128 | .else | |
129 | CFI_DEF_CFA_OFFSET SS+8 | |
130 | .endif | |
131 | CFI_REL_OFFSET r15,R15 | |
132 | CFI_REL_OFFSET r14,R14 | |
133 | CFI_REL_OFFSET r13,R13 | |
134 | CFI_REL_OFFSET r12,R12 | |
135 | CFI_REL_OFFSET rbp,RBP | |
136 | CFI_REL_OFFSET rbx,RBX | |
137 | CFI_REL_OFFSET r11,R11 | |
138 | CFI_REL_OFFSET r10,R10 | |
139 | CFI_REL_OFFSET r9,R9 | |
140 | CFI_REL_OFFSET r8,R8 | |
141 | CFI_REL_OFFSET rax,RAX | |
142 | CFI_REL_OFFSET rcx,RCX | |
143 | CFI_REL_OFFSET rdx,RDX | |
144 | CFI_REL_OFFSET rsi,RSI | |
145 | CFI_REL_OFFSET rdi,RDI | |
146 | CFI_REL_OFFSET rip,RIP | |
147 | /*CFI_REL_OFFSET cs,CS*/ | |
148 | /*CFI_REL_OFFSET rflags,EFLAGS*/ | |
149 | CFI_REL_OFFSET rsp,RSP | |
150 | /*CFI_REL_OFFSET ss,SS*/ | |
1da177e4 LT |
151 | .endm |
152 | /* | |
153 | * A newly forked process directly context switches into this. | |
154 | */ | |
155 | /* rdi: prev */ | |
156 | ENTRY(ret_from_fork) | |
1da177e4 | 157 | CFI_DEFAULT_STACK |
658fdbef AK |
158 | push kernel_eflags(%rip) |
159 | CFI_ADJUST_CFA_OFFSET 4 | |
160 | popf # reset kernel eflags | |
161 | CFI_ADJUST_CFA_OFFSET -4 | |
1da177e4 LT |
162 | call schedule_tail |
163 | GET_THREAD_INFO(%rcx) | |
164 | testl $(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT),threadinfo_flags(%rcx) | |
165 | jnz rff_trace | |
166 | rff_action: | |
167 | RESTORE_REST | |
168 | testl $3,CS-ARGOFFSET(%rsp) # from kernel_thread? | |
169 | je int_ret_from_sys_call | |
170 | testl $_TIF_IA32,threadinfo_flags(%rcx) | |
171 | jnz int_ret_from_sys_call | |
172 | RESTORE_TOP_OF_STACK %rdi,ARGOFFSET | |
173 | jmp ret_from_sys_call | |
174 | rff_trace: | |
175 | movq %rsp,%rdi | |
176 | call syscall_trace_leave | |
177 | GET_THREAD_INFO(%rcx) | |
178 | jmp rff_action | |
179 | CFI_ENDPROC | |
4b787e0b | 180 | END(ret_from_fork) |
1da177e4 LT |
181 | |
182 | /* | |
183 | * System call entry. Upto 6 arguments in registers are supported. | |
184 | * | |
185 | * SYSCALL does not save anything on the stack and does not change the | |
186 | * stack pointer. | |
187 | */ | |
188 | ||
189 | /* | |
190 | * Register setup: | |
191 | * rax system call number | |
192 | * rdi arg0 | |
193 | * rcx return address for syscall/sysret, C arg3 | |
194 | * rsi arg1 | |
195 | * rdx arg2 | |
196 | * r10 arg3 (--> moved to rcx for C) | |
197 | * r8 arg4 | |
198 | * r9 arg5 | |
199 | * r11 eflags for syscall/sysret, temporary for C | |
200 | * r12-r15,rbp,rbx saved by C code, not touched. | |
201 | * | |
202 | * Interrupts are off on entry. | |
203 | * Only called from user space. | |
204 | * | |
205 | * XXX if we had a free scratch register we could save the RSP into the stack frame | |
206 | * and report it properly in ps. Unfortunately we haven't. | |
7bf36bbc AK |
207 | * |
208 | * When user can change the frames always force IRET. That is because | |
209 | * it deals with uncanonical addresses better. SYSRET has trouble | |
210 | * with them due to bugs in both AMD and Intel CPUs. | |
1da177e4 LT |
211 | */ |
212 | ||
213 | ENTRY(system_call) | |
7effaa88 | 214 | CFI_STARTPROC simple |
adf14236 | 215 | CFI_SIGNAL_FRAME |
dffead4e | 216 | CFI_DEF_CFA rsp,PDA_STACKOFFSET |
7effaa88 JB |
217 | CFI_REGISTER rip,rcx |
218 | /*CFI_REGISTER rflags,r11*/ | |
1da177e4 LT |
219 | swapgs |
220 | movq %rsp,%gs:pda_oldrsp | |
221 | movq %gs:pda_kernelstack,%rsp | |
2601e64d IM |
222 | /* |
223 | * No need to follow this irqs off/on section - it's straight | |
224 | * and short: | |
225 | */ | |
1da177e4 LT |
226 | sti |
227 | SAVE_ARGS 8,1 | |
228 | movq %rax,ORIG_RAX-ARGOFFSET(%rsp) | |
7effaa88 JB |
229 | movq %rcx,RIP-ARGOFFSET(%rsp) |
230 | CFI_REL_OFFSET rip,RIP-ARGOFFSET | |
1da177e4 LT |
231 | GET_THREAD_INFO(%rcx) |
232 | testl $(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT|_TIF_SECCOMP),threadinfo_flags(%rcx) | |
233 | jnz tracesys | |
234 | cmpq $__NR_syscall_max,%rax | |
235 | ja badsys | |
236 | movq %r10,%rcx | |
237 | call *sys_call_table(,%rax,8) # XXX: rip relative | |
238 | movq %rax,RAX-ARGOFFSET(%rsp) | |
239 | /* | |
240 | * Syscall return path ending with SYSRET (fast path) | |
241 | * Has incomplete stack frame and undefined top of stack. | |
242 | */ | |
1da177e4 | 243 | ret_from_sys_call: |
11b854b2 | 244 | movl $_TIF_ALLWORK_MASK,%edi |
1da177e4 LT |
245 | /* edi: flagmask */ |
246 | sysret_check: | |
10cd706d | 247 | LOCKDEP_SYS_EXIT |
1da177e4 LT |
248 | GET_THREAD_INFO(%rcx) |
249 | cli | |
2601e64d | 250 | TRACE_IRQS_OFF |
1da177e4 LT |
251 | movl threadinfo_flags(%rcx),%edx |
252 | andl %edi,%edx | |
253 | jnz sysret_careful | |
bcddc015 | 254 | CFI_REMEMBER_STATE |
2601e64d IM |
255 | /* |
256 | * sysretq will re-enable interrupts: | |
257 | */ | |
258 | TRACE_IRQS_ON | |
1da177e4 | 259 | movq RIP-ARGOFFSET(%rsp),%rcx |
7effaa88 | 260 | CFI_REGISTER rip,rcx |
1da177e4 | 261 | RESTORE_ARGS 0,-ARG_SKIP,1 |
7effaa88 | 262 | /*CFI_REGISTER rflags,r11*/ |
1da177e4 LT |
263 | movq %gs:pda_oldrsp,%rsp |
264 | swapgs | |
265 | sysretq | |
266 | ||
bcddc015 | 267 | CFI_RESTORE_STATE |
1da177e4 LT |
268 | /* Handle reschedules */ |
269 | /* edx: work, edi: workmask */ | |
270 | sysret_careful: | |
271 | bt $TIF_NEED_RESCHED,%edx | |
272 | jnc sysret_signal | |
2601e64d | 273 | TRACE_IRQS_ON |
1da177e4 LT |
274 | sti |
275 | pushq %rdi | |
7effaa88 | 276 | CFI_ADJUST_CFA_OFFSET 8 |
1da177e4 LT |
277 | call schedule |
278 | popq %rdi | |
7effaa88 | 279 | CFI_ADJUST_CFA_OFFSET -8 |
1da177e4 LT |
280 | jmp sysret_check |
281 | ||
282 | /* Handle a signal */ | |
283 | sysret_signal: | |
2601e64d | 284 | TRACE_IRQS_ON |
1da177e4 | 285 | sti |
8f4d37ec | 286 | testl $_TIF_DO_NOTIFY_MASK,%edx |
10ffdbb8 AK |
287 | jz 1f |
288 | ||
289 | /* Really a signal */ | |
290 | /* edx: work flags (arg3) */ | |
1da177e4 LT |
291 | leaq do_notify_resume(%rip),%rax |
292 | leaq -ARGOFFSET(%rsp),%rdi # &pt_regs -> arg1 | |
293 | xorl %esi,%esi # oldset -> arg2 | |
294 | call ptregscall_common | |
10ffdbb8 | 295 | 1: movl $_TIF_NEED_RESCHED,%edi |
7bf36bbc AK |
296 | /* Use IRET because user could have changed frame. This |
297 | works because ptregscall_common has called FIXUP_TOP_OF_STACK. */ | |
298 | cli | |
2601e64d | 299 | TRACE_IRQS_OFF |
7bf36bbc | 300 | jmp int_with_check |
1da177e4 | 301 | |
7effaa88 JB |
302 | badsys: |
303 | movq $-ENOSYS,RAX-ARGOFFSET(%rsp) | |
304 | jmp ret_from_sys_call | |
305 | ||
1da177e4 LT |
306 | /* Do syscall tracing */ |
307 | tracesys: | |
308 | SAVE_REST | |
309 | movq $-ENOSYS,RAX(%rsp) | |
310 | FIXUP_TOP_OF_STACK %rdi | |
311 | movq %rsp,%rdi | |
312 | call syscall_trace_enter | |
313 | LOAD_ARGS ARGOFFSET /* reload args from stack in case ptrace changed it */ | |
314 | RESTORE_REST | |
315 | cmpq $__NR_syscall_max,%rax | |
cc7d479f JB |
316 | movq $-ENOSYS,%rcx |
317 | cmova %rcx,%rax | |
1da177e4 LT |
318 | ja 1f |
319 | movq %r10,%rcx /* fixup for C */ | |
320 | call *sys_call_table(,%rax,8) | |
822ff019 | 321 | 1: movq %rax,RAX-ARGOFFSET(%rsp) |
7bf36bbc | 322 | /* Use IRET because user could have changed frame */ |
1da177e4 | 323 | |
1da177e4 LT |
324 | /* |
325 | * Syscall return path ending with IRET. | |
326 | * Has correct top of stack, but partial stack frame. | |
bcddc015 JB |
327 | */ |
328 | .globl int_ret_from_sys_call | |
329 | int_ret_from_sys_call: | |
1da177e4 | 330 | cli |
2601e64d | 331 | TRACE_IRQS_OFF |
1da177e4 LT |
332 | testl $3,CS-ARGOFFSET(%rsp) |
333 | je retint_restore_args | |
334 | movl $_TIF_ALLWORK_MASK,%edi | |
335 | /* edi: mask to check */ | |
336 | int_with_check: | |
10cd706d | 337 | LOCKDEP_SYS_EXIT_IRQ |
1da177e4 LT |
338 | GET_THREAD_INFO(%rcx) |
339 | movl threadinfo_flags(%rcx),%edx | |
340 | andl %edi,%edx | |
341 | jnz int_careful | |
bf2fcc6f | 342 | andl $~TS_COMPAT,threadinfo_status(%rcx) |
1da177e4 LT |
343 | jmp retint_swapgs |
344 | ||
345 | /* Either reschedule or signal or syscall exit tracking needed. */ | |
346 | /* First do a reschedule test. */ | |
347 | /* edx: work, edi: workmask */ | |
348 | int_careful: | |
349 | bt $TIF_NEED_RESCHED,%edx | |
350 | jnc int_very_careful | |
2601e64d | 351 | TRACE_IRQS_ON |
1da177e4 LT |
352 | sti |
353 | pushq %rdi | |
7effaa88 | 354 | CFI_ADJUST_CFA_OFFSET 8 |
1da177e4 LT |
355 | call schedule |
356 | popq %rdi | |
7effaa88 | 357 | CFI_ADJUST_CFA_OFFSET -8 |
cdd219cd | 358 | cli |
2601e64d | 359 | TRACE_IRQS_OFF |
1da177e4 LT |
360 | jmp int_with_check |
361 | ||
362 | /* handle signals and tracing -- both require a full stack frame */ | |
363 | int_very_careful: | |
2601e64d | 364 | TRACE_IRQS_ON |
1da177e4 LT |
365 | sti |
366 | SAVE_REST | |
367 | /* Check for syscall exit trace */ | |
368 | testl $(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT|_TIF_SINGLESTEP),%edx | |
369 | jz int_signal | |
370 | pushq %rdi | |
7effaa88 | 371 | CFI_ADJUST_CFA_OFFSET 8 |
1da177e4 LT |
372 | leaq 8(%rsp),%rdi # &ptregs -> arg1 |
373 | call syscall_trace_leave | |
374 | popq %rdi | |
7effaa88 | 375 | CFI_ADJUST_CFA_OFFSET -8 |
36c1104e | 376 | andl $~(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT|_TIF_SINGLESTEP),%edi |
1da177e4 LT |
377 | jmp int_restore_rest |
378 | ||
379 | int_signal: | |
8f4d37ec | 380 | testl $_TIF_DO_NOTIFY_MASK,%edx |
1da177e4 LT |
381 | jz 1f |
382 | movq %rsp,%rdi # &ptregs -> arg1 | |
383 | xorl %esi,%esi # oldset -> arg2 | |
384 | call do_notify_resume | |
385 | 1: movl $_TIF_NEED_RESCHED,%edi | |
386 | int_restore_rest: | |
387 | RESTORE_REST | |
be9e6870 | 388 | cli |
2601e64d | 389 | TRACE_IRQS_OFF |
1da177e4 LT |
390 | jmp int_with_check |
391 | CFI_ENDPROC | |
bcddc015 | 392 | END(system_call) |
1da177e4 LT |
393 | |
394 | /* | |
395 | * Certain special system calls that need to save a complete full stack frame. | |
396 | */ | |
397 | ||
398 | .macro PTREGSCALL label,func,arg | |
399 | .globl \label | |
400 | \label: | |
401 | leaq \func(%rip),%rax | |
402 | leaq -ARGOFFSET+8(%rsp),\arg /* 8 for return address */ | |
403 | jmp ptregscall_common | |
4b787e0b | 404 | END(\label) |
1da177e4 LT |
405 | .endm |
406 | ||
7effaa88 JB |
407 | CFI_STARTPROC |
408 | ||
1da177e4 LT |
409 | PTREGSCALL stub_clone, sys_clone, %r8 |
410 | PTREGSCALL stub_fork, sys_fork, %rdi | |
411 | PTREGSCALL stub_vfork, sys_vfork, %rdi | |
412 | PTREGSCALL stub_rt_sigsuspend, sys_rt_sigsuspend, %rdx | |
413 | PTREGSCALL stub_sigaltstack, sys_sigaltstack, %rdx | |
414 | PTREGSCALL stub_iopl, sys_iopl, %rsi | |
415 | ||
416 | ENTRY(ptregscall_common) | |
1da177e4 | 417 | popq %r11 |
7effaa88 JB |
418 | CFI_ADJUST_CFA_OFFSET -8 |
419 | CFI_REGISTER rip, r11 | |
1da177e4 LT |
420 | SAVE_REST |
421 | movq %r11, %r15 | |
7effaa88 | 422 | CFI_REGISTER rip, r15 |
1da177e4 LT |
423 | FIXUP_TOP_OF_STACK %r11 |
424 | call *%rax | |
425 | RESTORE_TOP_OF_STACK %r11 | |
426 | movq %r15, %r11 | |
7effaa88 | 427 | CFI_REGISTER rip, r11 |
1da177e4 LT |
428 | RESTORE_REST |
429 | pushq %r11 | |
7effaa88 JB |
430 | CFI_ADJUST_CFA_OFFSET 8 |
431 | CFI_REL_OFFSET rip, 0 | |
1da177e4 LT |
432 | ret |
433 | CFI_ENDPROC | |
4b787e0b | 434 | END(ptregscall_common) |
1da177e4 LT |
435 | |
436 | ENTRY(stub_execve) | |
437 | CFI_STARTPROC | |
438 | popq %r11 | |
7effaa88 JB |
439 | CFI_ADJUST_CFA_OFFSET -8 |
440 | CFI_REGISTER rip, r11 | |
1da177e4 | 441 | SAVE_REST |
1da177e4 LT |
442 | FIXUP_TOP_OF_STACK %r11 |
443 | call sys_execve | |
1da177e4 | 444 | RESTORE_TOP_OF_STACK %r11 |
1da177e4 LT |
445 | movq %rax,RAX(%rsp) |
446 | RESTORE_REST | |
447 | jmp int_ret_from_sys_call | |
448 | CFI_ENDPROC | |
4b787e0b | 449 | END(stub_execve) |
1da177e4 LT |
450 | |
451 | /* | |
452 | * sigreturn is special because it needs to restore all registers on return. | |
453 | * This cannot be done with SYSRET, so use the IRET return path instead. | |
454 | */ | |
455 | ENTRY(stub_rt_sigreturn) | |
456 | CFI_STARTPROC | |
7effaa88 JB |
457 | addq $8, %rsp |
458 | CFI_ADJUST_CFA_OFFSET -8 | |
1da177e4 LT |
459 | SAVE_REST |
460 | movq %rsp,%rdi | |
461 | FIXUP_TOP_OF_STACK %r11 | |
462 | call sys_rt_sigreturn | |
463 | movq %rax,RAX(%rsp) # fixme, this could be done at the higher layer | |
464 | RESTORE_REST | |
465 | jmp int_ret_from_sys_call | |
466 | CFI_ENDPROC | |
4b787e0b | 467 | END(stub_rt_sigreturn) |
1da177e4 | 468 | |
7effaa88 JB |
469 | /* |
470 | * initial frame state for interrupts and exceptions | |
471 | */ | |
472 | .macro _frame ref | |
473 | CFI_STARTPROC simple | |
adf14236 | 474 | CFI_SIGNAL_FRAME |
7effaa88 JB |
475 | CFI_DEF_CFA rsp,SS+8-\ref |
476 | /*CFI_REL_OFFSET ss,SS-\ref*/ | |
477 | CFI_REL_OFFSET rsp,RSP-\ref | |
478 | /*CFI_REL_OFFSET rflags,EFLAGS-\ref*/ | |
479 | /*CFI_REL_OFFSET cs,CS-\ref*/ | |
480 | CFI_REL_OFFSET rip,RIP-\ref | |
481 | .endm | |
482 | ||
483 | /* initial frame state for interrupts (and exceptions without error code) */ | |
484 | #define INTR_FRAME _frame RIP | |
485 | /* initial frame state for exceptions with error code (and interrupts with | |
486 | vector already pushed) */ | |
487 | #define XCPT_FRAME _frame ORIG_RAX | |
488 | ||
1da177e4 LT |
489 | /* |
490 | * Interrupt entry/exit. | |
491 | * | |
492 | * Interrupt entry points save only callee clobbered registers in fast path. | |
493 | * | |
494 | * Entry runs with interrupts off. | |
495 | */ | |
496 | ||
497 | /* 0(%rsp): interrupt number */ | |
498 | .macro interrupt func | |
1da177e4 | 499 | cld |
1da177e4 LT |
500 | SAVE_ARGS |
501 | leaq -ARGOFFSET(%rsp),%rdi # arg1 for handler | |
1de9c3f6 JB |
502 | pushq %rbp |
503 | CFI_ADJUST_CFA_OFFSET 8 | |
504 | CFI_REL_OFFSET rbp, 0 | |
505 | movq %rsp,%rbp | |
506 | CFI_DEF_CFA_REGISTER rbp | |
1da177e4 LT |
507 | testl $3,CS(%rdi) |
508 | je 1f | |
509 | swapgs | |
96e54049 AK |
510 | /* irqcount is used to check if a CPU is already on an interrupt |
511 | stack or not. While this is essentially redundant with preempt_count | |
512 | it is a little cheaper to use a separate counter in the PDA | |
513 | (short of moving irq_enter into assembly, which would be too | |
514 | much work) */ | |
515 | 1: incl %gs:pda_irqcount | |
1de9c3f6 | 516 | cmoveq %gs:pda_irqstackptr,%rsp |
2699500b | 517 | push %rbp # backlink for old unwinder |
2601e64d IM |
518 | /* |
519 | * We entered an interrupt context - irqs are off: | |
520 | */ | |
521 | TRACE_IRQS_OFF | |
1da177e4 LT |
522 | call \func |
523 | .endm | |
524 | ||
525 | ENTRY(common_interrupt) | |
7effaa88 | 526 | XCPT_FRAME |
1da177e4 LT |
527 | interrupt do_IRQ |
528 | /* 0(%rsp): oldrsp-ARGOFFSET */ | |
7effaa88 | 529 | ret_from_intr: |
1da177e4 | 530 | cli |
2601e64d | 531 | TRACE_IRQS_OFF |
3829ee6b | 532 | decl %gs:pda_irqcount |
1de9c3f6 | 533 | leaveq |
7effaa88 | 534 | CFI_DEF_CFA_REGISTER rsp |
1de9c3f6 | 535 | CFI_ADJUST_CFA_OFFSET -8 |
7effaa88 | 536 | exit_intr: |
1da177e4 LT |
537 | GET_THREAD_INFO(%rcx) |
538 | testl $3,CS-ARGOFFSET(%rsp) | |
539 | je retint_kernel | |
540 | ||
541 | /* Interrupt came from user space */ | |
542 | /* | |
543 | * Has a correct top of stack, but a partial stack frame | |
544 | * %rcx: thread info. Interrupts off. | |
545 | */ | |
546 | retint_with_reschedule: | |
547 | movl $_TIF_WORK_MASK,%edi | |
7effaa88 | 548 | retint_check: |
10cd706d | 549 | LOCKDEP_SYS_EXIT_IRQ |
1da177e4 LT |
550 | movl threadinfo_flags(%rcx),%edx |
551 | andl %edi,%edx | |
7effaa88 | 552 | CFI_REMEMBER_STATE |
1da177e4 | 553 | jnz retint_careful |
10cd706d PZ |
554 | |
555 | retint_swapgs: /* return to user-space */ | |
2601e64d IM |
556 | /* |
557 | * The iretq could re-enable interrupts: | |
558 | */ | |
559 | cli | |
560 | TRACE_IRQS_IRETQ | |
1da177e4 | 561 | swapgs |
2601e64d IM |
562 | jmp restore_args |
563 | ||
10cd706d | 564 | retint_restore_args: /* return to kernel space */ |
1da177e4 | 565 | cli |
2601e64d IM |
566 | /* |
567 | * The iretq could re-enable interrupts: | |
568 | */ | |
569 | TRACE_IRQS_IRETQ | |
570 | restore_args: | |
1da177e4 LT |
571 | RESTORE_ARGS 0,8,0 |
572 | iret_label: | |
573 | iretq | |
574 | ||
575 | .section __ex_table,"a" | |
576 | .quad iret_label,bad_iret | |
577 | .previous | |
578 | .section .fixup,"ax" | |
579 | /* force a signal here? this matches i386 behaviour */ | |
580 | /* running with kernel gs */ | |
581 | bad_iret: | |
3076a492 | 582 | movq $11,%rdi /* SIGSEGV */ |
2601e64d | 583 | TRACE_IRQS_ON |
2391c4b5 | 584 | sti |
1da177e4 LT |
585 | jmp do_exit |
586 | .previous | |
587 | ||
7effaa88 | 588 | /* edi: workmask, edx: work */ |
1da177e4 | 589 | retint_careful: |
7effaa88 | 590 | CFI_RESTORE_STATE |
1da177e4 LT |
591 | bt $TIF_NEED_RESCHED,%edx |
592 | jnc retint_signal | |
2601e64d | 593 | TRACE_IRQS_ON |
1da177e4 LT |
594 | sti |
595 | pushq %rdi | |
7effaa88 | 596 | CFI_ADJUST_CFA_OFFSET 8 |
1da177e4 LT |
597 | call schedule |
598 | popq %rdi | |
7effaa88 | 599 | CFI_ADJUST_CFA_OFFSET -8 |
1da177e4 LT |
600 | GET_THREAD_INFO(%rcx) |
601 | cli | |
2601e64d | 602 | TRACE_IRQS_OFF |
1da177e4 LT |
603 | jmp retint_check |
604 | ||
605 | retint_signal: | |
8f4d37ec | 606 | testl $_TIF_DO_NOTIFY_MASK,%edx |
10ffdbb8 | 607 | jz retint_swapgs |
2601e64d | 608 | TRACE_IRQS_ON |
1da177e4 LT |
609 | sti |
610 | SAVE_REST | |
611 | movq $-1,ORIG_RAX(%rsp) | |
3829ee6b | 612 | xorl %esi,%esi # oldset |
1da177e4 LT |
613 | movq %rsp,%rdi # &pt_regs |
614 | call do_notify_resume | |
615 | RESTORE_REST | |
616 | cli | |
2601e64d | 617 | TRACE_IRQS_OFF |
10ffdbb8 | 618 | movl $_TIF_NEED_RESCHED,%edi |
be9e6870 | 619 | GET_THREAD_INFO(%rcx) |
1da177e4 LT |
620 | jmp retint_check |
621 | ||
622 | #ifdef CONFIG_PREEMPT | |
623 | /* Returning to kernel space. Check if we need preemption */ | |
624 | /* rcx: threadinfo. interrupts off. */ | |
b06babac | 625 | ENTRY(retint_kernel) |
1da177e4 LT |
626 | cmpl $0,threadinfo_preempt_count(%rcx) |
627 | jnz retint_restore_args | |
628 | bt $TIF_NEED_RESCHED,threadinfo_flags(%rcx) | |
629 | jnc retint_restore_args | |
630 | bt $9,EFLAGS-ARGOFFSET(%rsp) /* interrupts off? */ | |
631 | jnc retint_restore_args | |
632 | call preempt_schedule_irq | |
633 | jmp exit_intr | |
634 | #endif | |
4b787e0b | 635 | |
1da177e4 | 636 | CFI_ENDPROC |
4b787e0b | 637 | END(common_interrupt) |
1da177e4 LT |
638 | |
639 | /* | |
640 | * APIC interrupts. | |
641 | */ | |
642 | .macro apicinterrupt num,func | |
7effaa88 | 643 | INTR_FRAME |
19eadf98 | 644 | pushq $~(\num) |
7effaa88 | 645 | CFI_ADJUST_CFA_OFFSET 8 |
1da177e4 LT |
646 | interrupt \func |
647 | jmp ret_from_intr | |
648 | CFI_ENDPROC | |
649 | .endm | |
650 | ||
651 | ENTRY(thermal_interrupt) | |
652 | apicinterrupt THERMAL_APIC_VECTOR,smp_thermal_interrupt | |
4b787e0b | 653 | END(thermal_interrupt) |
1da177e4 | 654 | |
89b831ef JS |
655 | ENTRY(threshold_interrupt) |
656 | apicinterrupt THRESHOLD_APIC_VECTOR,mce_threshold_interrupt | |
4b787e0b | 657 | END(threshold_interrupt) |
89b831ef | 658 | |
1da177e4 LT |
659 | #ifdef CONFIG_SMP |
660 | ENTRY(reschedule_interrupt) | |
661 | apicinterrupt RESCHEDULE_VECTOR,smp_reschedule_interrupt | |
4b787e0b | 662 | END(reschedule_interrupt) |
1da177e4 | 663 | |
e5bc8b6b AK |
664 | .macro INVALIDATE_ENTRY num |
665 | ENTRY(invalidate_interrupt\num) | |
666 | apicinterrupt INVALIDATE_TLB_VECTOR_START+\num,smp_invalidate_interrupt | |
4b787e0b | 667 | END(invalidate_interrupt\num) |
e5bc8b6b AK |
668 | .endm |
669 | ||
670 | INVALIDATE_ENTRY 0 | |
671 | INVALIDATE_ENTRY 1 | |
672 | INVALIDATE_ENTRY 2 | |
673 | INVALIDATE_ENTRY 3 | |
674 | INVALIDATE_ENTRY 4 | |
675 | INVALIDATE_ENTRY 5 | |
676 | INVALIDATE_ENTRY 6 | |
677 | INVALIDATE_ENTRY 7 | |
1da177e4 LT |
678 | |
679 | ENTRY(call_function_interrupt) | |
680 | apicinterrupt CALL_FUNCTION_VECTOR,smp_call_function_interrupt | |
4b787e0b | 681 | END(call_function_interrupt) |
61014292 EB |
682 | ENTRY(irq_move_cleanup_interrupt) |
683 | apicinterrupt IRQ_MOVE_CLEANUP_VECTOR,smp_irq_move_cleanup_interrupt | |
684 | END(irq_move_cleanup_interrupt) | |
1da177e4 LT |
685 | #endif |
686 | ||
1da177e4 LT |
687 | ENTRY(apic_timer_interrupt) |
688 | apicinterrupt LOCAL_TIMER_VECTOR,smp_apic_timer_interrupt | |
4b787e0b | 689 | END(apic_timer_interrupt) |
1da177e4 LT |
690 | |
691 | ENTRY(error_interrupt) | |
692 | apicinterrupt ERROR_APIC_VECTOR,smp_error_interrupt | |
4b787e0b | 693 | END(error_interrupt) |
1da177e4 LT |
694 | |
695 | ENTRY(spurious_interrupt) | |
696 | apicinterrupt SPURIOUS_APIC_VECTOR,smp_spurious_interrupt | |
4b787e0b | 697 | END(spurious_interrupt) |
1da177e4 LT |
698 | |
699 | /* | |
700 | * Exception entry points. | |
701 | */ | |
702 | .macro zeroentry sym | |
7effaa88 | 703 | INTR_FRAME |
1da177e4 | 704 | pushq $0 /* push error code/oldrax */ |
7effaa88 | 705 | CFI_ADJUST_CFA_OFFSET 8 |
1da177e4 | 706 | pushq %rax /* push real oldrax to the rdi slot */ |
7effaa88 | 707 | CFI_ADJUST_CFA_OFFSET 8 |
37550907 | 708 | CFI_REL_OFFSET rax,0 |
1da177e4 LT |
709 | leaq \sym(%rip),%rax |
710 | jmp error_entry | |
7effaa88 | 711 | CFI_ENDPROC |
1da177e4 LT |
712 | .endm |
713 | ||
714 | .macro errorentry sym | |
7effaa88 | 715 | XCPT_FRAME |
1da177e4 | 716 | pushq %rax |
7effaa88 | 717 | CFI_ADJUST_CFA_OFFSET 8 |
37550907 | 718 | CFI_REL_OFFSET rax,0 |
1da177e4 LT |
719 | leaq \sym(%rip),%rax |
720 | jmp error_entry | |
7effaa88 | 721 | CFI_ENDPROC |
1da177e4 LT |
722 | .endm |
723 | ||
724 | /* error code is on the stack already */ | |
725 | /* handle NMI like exceptions that can happen everywhere */ | |
2601e64d | 726 | .macro paranoidentry sym, ist=0, irqtrace=1 |
1da177e4 LT |
727 | SAVE_ALL |
728 | cld | |
729 | movl $1,%ebx | |
730 | movl $MSR_GS_BASE,%ecx | |
731 | rdmsr | |
732 | testl %edx,%edx | |
733 | js 1f | |
734 | swapgs | |
735 | xorl %ebx,%ebx | |
b556b35e JB |
736 | 1: |
737 | .if \ist | |
738 | movq %gs:pda_data_offset, %rbp | |
739 | .endif | |
740 | movq %rsp,%rdi | |
1da177e4 LT |
741 | movq ORIG_RAX(%rsp),%rsi |
742 | movq $-1,ORIG_RAX(%rsp) | |
b556b35e | 743 | .if \ist |
5f8efbb9 | 744 | subq $EXCEPTION_STKSZ, per_cpu__init_tss + TSS_ist + (\ist - 1) * 8(%rbp) |
b556b35e | 745 | .endif |
1da177e4 | 746 | call \sym |
b556b35e | 747 | .if \ist |
5f8efbb9 | 748 | addq $EXCEPTION_STKSZ, per_cpu__init_tss + TSS_ist + (\ist - 1) * 8(%rbp) |
b556b35e | 749 | .endif |
6fefb0d1 | 750 | cli |
2601e64d IM |
751 | .if \irqtrace |
752 | TRACE_IRQS_OFF | |
753 | .endif | |
1da177e4 | 754 | .endm |
2601e64d IM |
755 | |
756 | /* | |
757 | * "Paranoid" exit path from exception stack. | |
758 | * Paranoid because this is used by NMIs and cannot take | |
759 | * any kernel state for granted. | |
760 | * We don't do kernel preemption checks here, because only | |
761 | * NMI should be common and it does not enable IRQs and | |
762 | * cannot get reschedule ticks. | |
763 | * | |
764 | * "trace" is 0 for the NMI handler only, because irq-tracing | |
765 | * is fundamentally NMI-unsafe. (we cannot change the soft and | |
766 | * hard flags at once, atomically) | |
767 | */ | |
768 | .macro paranoidexit trace=1 | |
769 | /* ebx: no swapgs flag */ | |
770 | paranoid_exit\trace: | |
771 | testl %ebx,%ebx /* swapgs needed? */ | |
772 | jnz paranoid_restore\trace | |
773 | testl $3,CS(%rsp) | |
774 | jnz paranoid_userspace\trace | |
775 | paranoid_swapgs\trace: | |
7a0a2dff | 776 | .if \trace |
2601e64d | 777 | TRACE_IRQS_IRETQ 0 |
7a0a2dff | 778 | .endif |
2601e64d IM |
779 | swapgs |
780 | paranoid_restore\trace: | |
781 | RESTORE_ALL 8 | |
782 | iretq | |
783 | paranoid_userspace\trace: | |
784 | GET_THREAD_INFO(%rcx) | |
785 | movl threadinfo_flags(%rcx),%ebx | |
786 | andl $_TIF_WORK_MASK,%ebx | |
787 | jz paranoid_swapgs\trace | |
788 | movq %rsp,%rdi /* &pt_regs */ | |
789 | call sync_regs | |
790 | movq %rax,%rsp /* switch stack for scheduling */ | |
791 | testl $_TIF_NEED_RESCHED,%ebx | |
792 | jnz paranoid_schedule\trace | |
793 | movl %ebx,%edx /* arg3: thread flags */ | |
794 | .if \trace | |
795 | TRACE_IRQS_ON | |
796 | .endif | |
797 | sti | |
798 | xorl %esi,%esi /* arg2: oldset */ | |
799 | movq %rsp,%rdi /* arg1: &pt_regs */ | |
800 | call do_notify_resume | |
801 | cli | |
802 | .if \trace | |
803 | TRACE_IRQS_OFF | |
804 | .endif | |
805 | jmp paranoid_userspace\trace | |
806 | paranoid_schedule\trace: | |
807 | .if \trace | |
808 | TRACE_IRQS_ON | |
809 | .endif | |
810 | sti | |
811 | call schedule | |
812 | cli | |
813 | .if \trace | |
814 | TRACE_IRQS_OFF | |
815 | .endif | |
816 | jmp paranoid_userspace\trace | |
817 | CFI_ENDPROC | |
818 | .endm | |
819 | ||
1da177e4 LT |
820 | /* |
821 | * Exception entry point. This expects an error code/orig_rax on the stack | |
822 | * and the exception handler in %rax. | |
823 | */ | |
d28c4393 | 824 | KPROBE_ENTRY(error_entry) |
7effaa88 | 825 | _frame RDI |
37550907 | 826 | CFI_REL_OFFSET rax,0 |
1da177e4 LT |
827 | /* rdi slot contains rax, oldrax contains error code */ |
828 | cld | |
829 | subq $14*8,%rsp | |
830 | CFI_ADJUST_CFA_OFFSET (14*8) | |
831 | movq %rsi,13*8(%rsp) | |
832 | CFI_REL_OFFSET rsi,RSI | |
833 | movq 14*8(%rsp),%rsi /* load rax from rdi slot */ | |
37550907 | 834 | CFI_REGISTER rax,rsi |
1da177e4 LT |
835 | movq %rdx,12*8(%rsp) |
836 | CFI_REL_OFFSET rdx,RDX | |
837 | movq %rcx,11*8(%rsp) | |
838 | CFI_REL_OFFSET rcx,RCX | |
839 | movq %rsi,10*8(%rsp) /* store rax */ | |
840 | CFI_REL_OFFSET rax,RAX | |
841 | movq %r8, 9*8(%rsp) | |
842 | CFI_REL_OFFSET r8,R8 | |
843 | movq %r9, 8*8(%rsp) | |
844 | CFI_REL_OFFSET r9,R9 | |
845 | movq %r10,7*8(%rsp) | |
846 | CFI_REL_OFFSET r10,R10 | |
847 | movq %r11,6*8(%rsp) | |
848 | CFI_REL_OFFSET r11,R11 | |
849 | movq %rbx,5*8(%rsp) | |
850 | CFI_REL_OFFSET rbx,RBX | |
851 | movq %rbp,4*8(%rsp) | |
852 | CFI_REL_OFFSET rbp,RBP | |
853 | movq %r12,3*8(%rsp) | |
854 | CFI_REL_OFFSET r12,R12 | |
855 | movq %r13,2*8(%rsp) | |
856 | CFI_REL_OFFSET r13,R13 | |
857 | movq %r14,1*8(%rsp) | |
858 | CFI_REL_OFFSET r14,R14 | |
859 | movq %r15,(%rsp) | |
860 | CFI_REL_OFFSET r15,R15 | |
861 | xorl %ebx,%ebx | |
862 | testl $3,CS(%rsp) | |
863 | je error_kernelspace | |
864 | error_swapgs: | |
865 | swapgs | |
866 | error_sti: | |
867 | movq %rdi,RDI(%rsp) | |
37550907 | 868 | CFI_REL_OFFSET rdi,RDI |
1da177e4 LT |
869 | movq %rsp,%rdi |
870 | movq ORIG_RAX(%rsp),%rsi /* get error code */ | |
871 | movq $-1,ORIG_RAX(%rsp) | |
872 | call *%rax | |
10cd706d PZ |
873 | /* ebx: no swapgs flag (1: don't need swapgs, 0: need it) */ |
874 | error_exit: | |
875 | movl %ebx,%eax | |
1da177e4 LT |
876 | RESTORE_REST |
877 | cli | |
2601e64d | 878 | TRACE_IRQS_OFF |
1da177e4 LT |
879 | GET_THREAD_INFO(%rcx) |
880 | testl %eax,%eax | |
881 | jne retint_kernel | |
10cd706d | 882 | LOCKDEP_SYS_EXIT_IRQ |
1da177e4 LT |
883 | movl threadinfo_flags(%rcx),%edx |
884 | movl $_TIF_WORK_MASK,%edi | |
885 | andl %edi,%edx | |
886 | jnz retint_careful | |
10cd706d | 887 | jmp retint_swapgs |
1da177e4 LT |
888 | CFI_ENDPROC |
889 | ||
890 | error_kernelspace: | |
891 | incl %ebx | |
892 | /* There are two places in the kernel that can potentially fault with | |
893 | usergs. Handle them here. The exception handlers after | |
894 | iret run with kernel gs again, so don't set the user space flag. | |
895 | B stepping K8s sometimes report an truncated RIP for IRET | |
896 | exceptions returning to compat mode. Check for these here too. */ | |
897 | leaq iret_label(%rip),%rbp | |
898 | cmpq %rbp,RIP(%rsp) | |
899 | je error_swapgs | |
900 | movl %ebp,%ebp /* zero extend */ | |
901 | cmpq %rbp,RIP(%rsp) | |
902 | je error_swapgs | |
903 | cmpq $gs_change,RIP(%rsp) | |
904 | je error_swapgs | |
905 | jmp error_sti | |
d28c4393 | 906 | KPROBE_END(error_entry) |
1da177e4 LT |
907 | |
908 | /* Reload gs selector with exception handling */ | |
909 | /* edi: new selector */ | |
910 | ENTRY(load_gs_index) | |
7effaa88 | 911 | CFI_STARTPROC |
1da177e4 | 912 | pushf |
7effaa88 | 913 | CFI_ADJUST_CFA_OFFSET 8 |
1da177e4 LT |
914 | cli |
915 | swapgs | |
916 | gs_change: | |
917 | movl %edi,%gs | |
918 | 2: mfence /* workaround */ | |
919 | swapgs | |
920 | popf | |
7effaa88 | 921 | CFI_ADJUST_CFA_OFFSET -8 |
1da177e4 | 922 | ret |
7effaa88 | 923 | CFI_ENDPROC |
4b787e0b | 924 | ENDPROC(load_gs_index) |
1da177e4 LT |
925 | |
926 | .section __ex_table,"a" | |
927 | .align 8 | |
928 | .quad gs_change,bad_gs | |
929 | .previous | |
930 | .section .fixup,"ax" | |
931 | /* running with kernelgs */ | |
932 | bad_gs: | |
933 | swapgs /* switch back to user gs */ | |
934 | xorl %eax,%eax | |
935 | movl %eax,%gs | |
936 | jmp 2b | |
937 | .previous | |
938 | ||
939 | /* | |
940 | * Create a kernel thread. | |
941 | * | |
942 | * C extern interface: | |
943 | * extern long kernel_thread(int (*fn)(void *), void * arg, unsigned long flags) | |
944 | * | |
945 | * asm input arguments: | |
946 | * rdi: fn, rsi: arg, rdx: flags | |
947 | */ | |
948 | ENTRY(kernel_thread) | |
949 | CFI_STARTPROC | |
950 | FAKE_STACK_FRAME $child_rip | |
951 | SAVE_ALL | |
952 | ||
953 | # rdi: flags, rsi: usp, rdx: will be &pt_regs | |
954 | movq %rdx,%rdi | |
955 | orq kernel_thread_flags(%rip),%rdi | |
956 | movq $-1, %rsi | |
957 | movq %rsp, %rdx | |
958 | ||
959 | xorl %r8d,%r8d | |
960 | xorl %r9d,%r9d | |
961 | ||
962 | # clone now | |
963 | call do_fork | |
964 | movq %rax,RAX(%rsp) | |
965 | xorl %edi,%edi | |
966 | ||
967 | /* | |
968 | * It isn't worth to check for reschedule here, | |
969 | * so internally to the x86_64 port you can rely on kernel_thread() | |
970 | * not to reschedule the child before returning, this avoids the need | |
971 | * of hacks for example to fork off the per-CPU idle tasks. | |
972 | * [Hopefully no generic code relies on the reschedule -AK] | |
973 | */ | |
974 | RESTORE_ALL | |
975 | UNFAKE_STACK_FRAME | |
976 | ret | |
977 | CFI_ENDPROC | |
4b787e0b | 978 | ENDPROC(kernel_thread) |
1da177e4 LT |
979 | |
980 | child_rip: | |
c05991ed AK |
981 | pushq $0 # fake return address |
982 | CFI_STARTPROC | |
1da177e4 LT |
983 | /* |
984 | * Here we are in the child and the registers are set as they were | |
985 | * at kernel_thread() invocation in the parent. | |
986 | */ | |
987 | movq %rdi, %rax | |
988 | movq %rsi, %rdi | |
989 | call *%rax | |
990 | # exit | |
1c5b5cfd | 991 | mov %eax, %edi |
1da177e4 | 992 | call do_exit |
c05991ed | 993 | CFI_ENDPROC |
4b787e0b | 994 | ENDPROC(child_rip) |
1da177e4 LT |
995 | |
996 | /* | |
997 | * execve(). This function needs to use IRET, not SYSRET, to set up all state properly. | |
998 | * | |
999 | * C extern interface: | |
1000 | * extern long execve(char *name, char **argv, char **envp) | |
1001 | * | |
1002 | * asm input arguments: | |
1003 | * rdi: name, rsi: argv, rdx: envp | |
1004 | * | |
1005 | * We want to fallback into: | |
1006 | * extern long sys_execve(char *name, char **argv,char **envp, struct pt_regs regs) | |
1007 | * | |
1008 | * do_sys_execve asm fallback arguments: | |
1009 | * rdi: name, rsi: argv, rdx: envp, fake frame on the stack | |
1010 | */ | |
3db03b4a | 1011 | ENTRY(kernel_execve) |
1da177e4 LT |
1012 | CFI_STARTPROC |
1013 | FAKE_STACK_FRAME $0 | |
1014 | SAVE_ALL | |
1015 | call sys_execve | |
1016 | movq %rax, RAX(%rsp) | |
1017 | RESTORE_REST | |
1018 | testq %rax,%rax | |
1019 | je int_ret_from_sys_call | |
1020 | RESTORE_ARGS | |
1021 | UNFAKE_STACK_FRAME | |
1022 | ret | |
1023 | CFI_ENDPROC | |
3db03b4a | 1024 | ENDPROC(kernel_execve) |
1da177e4 | 1025 | |
0f2fbdcb | 1026 | KPROBE_ENTRY(page_fault) |
1da177e4 | 1027 | errorentry do_page_fault |
d28c4393 | 1028 | KPROBE_END(page_fault) |
1da177e4 LT |
1029 | |
1030 | ENTRY(coprocessor_error) | |
1031 | zeroentry do_coprocessor_error | |
4b787e0b | 1032 | END(coprocessor_error) |
1da177e4 LT |
1033 | |
1034 | ENTRY(simd_coprocessor_error) | |
1035 | zeroentry do_simd_coprocessor_error | |
4b787e0b | 1036 | END(simd_coprocessor_error) |
1da177e4 LT |
1037 | |
1038 | ENTRY(device_not_available) | |
1039 | zeroentry math_state_restore | |
4b787e0b | 1040 | END(device_not_available) |
1da177e4 LT |
1041 | |
1042 | /* runs on exception stack */ | |
0f2fbdcb | 1043 | KPROBE_ENTRY(debug) |
7effaa88 | 1044 | INTR_FRAME |
1da177e4 LT |
1045 | pushq $0 |
1046 | CFI_ADJUST_CFA_OFFSET 8 | |
5f8efbb9 | 1047 | paranoidentry do_debug, DEBUG_STACK |
2601e64d | 1048 | paranoidexit |
d28c4393 | 1049 | KPROBE_END(debug) |
1da177e4 LT |
1050 | |
1051 | /* runs on exception stack */ | |
eddb6fb9 | 1052 | KPROBE_ENTRY(nmi) |
7effaa88 | 1053 | INTR_FRAME |
1da177e4 | 1054 | pushq $-1 |
7effaa88 | 1055 | CFI_ADJUST_CFA_OFFSET 8 |
2601e64d IM |
1056 | paranoidentry do_nmi, 0, 0 |
1057 | #ifdef CONFIG_TRACE_IRQFLAGS | |
1058 | paranoidexit 0 | |
1059 | #else | |
1060 | jmp paranoid_exit1 | |
1061 | CFI_ENDPROC | |
1062 | #endif | |
d28c4393 | 1063 | KPROBE_END(nmi) |
6fefb0d1 | 1064 | |
0f2fbdcb | 1065 | KPROBE_ENTRY(int3) |
b556b35e JB |
1066 | INTR_FRAME |
1067 | pushq $0 | |
1068 | CFI_ADJUST_CFA_OFFSET 8 | |
5f8efbb9 | 1069 | paranoidentry do_int3, DEBUG_STACK |
2601e64d | 1070 | jmp paranoid_exit1 |
b556b35e | 1071 | CFI_ENDPROC |
d28c4393 | 1072 | KPROBE_END(int3) |
1da177e4 LT |
1073 | |
1074 | ENTRY(overflow) | |
1075 | zeroentry do_overflow | |
4b787e0b | 1076 | END(overflow) |
1da177e4 LT |
1077 | |
1078 | ENTRY(bounds) | |
1079 | zeroentry do_bounds | |
4b787e0b | 1080 | END(bounds) |
1da177e4 LT |
1081 | |
1082 | ENTRY(invalid_op) | |
1083 | zeroentry do_invalid_op | |
4b787e0b | 1084 | END(invalid_op) |
1da177e4 LT |
1085 | |
1086 | ENTRY(coprocessor_segment_overrun) | |
1087 | zeroentry do_coprocessor_segment_overrun | |
4b787e0b | 1088 | END(coprocessor_segment_overrun) |
1da177e4 LT |
1089 | |
1090 | ENTRY(reserved) | |
1091 | zeroentry do_reserved | |
4b787e0b | 1092 | END(reserved) |
1da177e4 LT |
1093 | |
1094 | /* runs on exception stack */ | |
1095 | ENTRY(double_fault) | |
7effaa88 | 1096 | XCPT_FRAME |
1da177e4 | 1097 | paranoidentry do_double_fault |
2601e64d | 1098 | jmp paranoid_exit1 |
1da177e4 | 1099 | CFI_ENDPROC |
4b787e0b | 1100 | END(double_fault) |
1da177e4 LT |
1101 | |
1102 | ENTRY(invalid_TSS) | |
1103 | errorentry do_invalid_TSS | |
4b787e0b | 1104 | END(invalid_TSS) |
1da177e4 LT |
1105 | |
1106 | ENTRY(segment_not_present) | |
1107 | errorentry do_segment_not_present | |
4b787e0b | 1108 | END(segment_not_present) |
1da177e4 LT |
1109 | |
1110 | /* runs on exception stack */ | |
1111 | ENTRY(stack_segment) | |
7effaa88 | 1112 | XCPT_FRAME |
1da177e4 | 1113 | paranoidentry do_stack_segment |
2601e64d | 1114 | jmp paranoid_exit1 |
1da177e4 | 1115 | CFI_ENDPROC |
4b787e0b | 1116 | END(stack_segment) |
1da177e4 | 1117 | |
0f2fbdcb | 1118 | KPROBE_ENTRY(general_protection) |
1da177e4 | 1119 | errorentry do_general_protection |
d28c4393 | 1120 | KPROBE_END(general_protection) |
1da177e4 LT |
1121 | |
1122 | ENTRY(alignment_check) | |
1123 | errorentry do_alignment_check | |
4b787e0b | 1124 | END(alignment_check) |
1da177e4 LT |
1125 | |
1126 | ENTRY(divide_error) | |
1127 | zeroentry do_divide_error | |
4b787e0b | 1128 | END(divide_error) |
1da177e4 LT |
1129 | |
1130 | ENTRY(spurious_interrupt_bug) | |
1131 | zeroentry do_spurious_interrupt_bug | |
4b787e0b | 1132 | END(spurious_interrupt_bug) |
1da177e4 LT |
1133 | |
1134 | #ifdef CONFIG_X86_MCE | |
1135 | /* runs on exception stack */ | |
1136 | ENTRY(machine_check) | |
7effaa88 | 1137 | INTR_FRAME |
1da177e4 LT |
1138 | pushq $0 |
1139 | CFI_ADJUST_CFA_OFFSET 8 | |
1140 | paranoidentry do_machine_check | |
2601e64d | 1141 | jmp paranoid_exit1 |
1da177e4 | 1142 | CFI_ENDPROC |
4b787e0b | 1143 | END(machine_check) |
1da177e4 LT |
1144 | #endif |
1145 | ||
2699500b | 1146 | /* Call softirq on interrupt stack. Interrupts are off. */ |
ed6b676c | 1147 | ENTRY(call_softirq) |
7effaa88 | 1148 | CFI_STARTPROC |
2699500b AK |
1149 | push %rbp |
1150 | CFI_ADJUST_CFA_OFFSET 8 | |
1151 | CFI_REL_OFFSET rbp,0 | |
1152 | mov %rsp,%rbp | |
1153 | CFI_DEF_CFA_REGISTER rbp | |
ed6b676c | 1154 | incl %gs:pda_irqcount |
2699500b AK |
1155 | cmove %gs:pda_irqstackptr,%rsp |
1156 | push %rbp # backlink for old unwinder | |
ed6b676c | 1157 | call __do_softirq |
2699500b | 1158 | leaveq |
7effaa88 | 1159 | CFI_DEF_CFA_REGISTER rsp |
2699500b | 1160 | CFI_ADJUST_CFA_OFFSET -8 |
ed6b676c | 1161 | decl %gs:pda_irqcount |
ed6b676c | 1162 | ret |
7effaa88 | 1163 | CFI_ENDPROC |
4b787e0b | 1164 | ENDPROC(call_softirq) |
75154f40 AK |
1165 | |
1166 | KPROBE_ENTRY(ignore_sysret) | |
1167 | CFI_STARTPROC | |
1168 | mov $-ENOSYS,%eax | |
1169 | sysret | |
1170 | CFI_ENDPROC | |
1171 | ENDPROC(ignore_sysret) |