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> |
72fe4858 | 53 | #include <asm/paravirt.h> |
395a59d0 | 54 | #include <asm/ftrace.h> |
1da177e4 LT |
55 | |
56 | .code64 | |
57 | ||
16444a8a | 58 | #ifdef CONFIG_FTRACE |
d61f82d0 SR |
59 | #ifdef CONFIG_DYNAMIC_FTRACE |
60 | ENTRY(mcount) | |
61 | ||
62 | subq $0x38, %rsp | |
63 | movq %rax, (%rsp) | |
64 | movq %rcx, 8(%rsp) | |
65 | movq %rdx, 16(%rsp) | |
66 | movq %rsi, 24(%rsp) | |
67 | movq %rdi, 32(%rsp) | |
68 | movq %r8, 40(%rsp) | |
69 | movq %r9, 48(%rsp) | |
70 | ||
71 | movq 0x38(%rsp), %rdi | |
395a59d0 | 72 | subq $MCOUNT_INSN_SIZE, %rdi |
d61f82d0 SR |
73 | |
74 | .globl mcount_call | |
75 | mcount_call: | |
76 | call ftrace_stub | |
77 | ||
78 | movq 48(%rsp), %r9 | |
79 | movq 40(%rsp), %r8 | |
80 | movq 32(%rsp), %rdi | |
81 | movq 24(%rsp), %rsi | |
82 | movq 16(%rsp), %rdx | |
83 | movq 8(%rsp), %rcx | |
84 | movq (%rsp), %rax | |
85 | addq $0x38, %rsp | |
86 | ||
87 | retq | |
88 | END(mcount) | |
89 | ||
90 | ENTRY(ftrace_caller) | |
91 | ||
92 | /* taken from glibc */ | |
93 | subq $0x38, %rsp | |
94 | movq %rax, (%rsp) | |
95 | movq %rcx, 8(%rsp) | |
96 | movq %rdx, 16(%rsp) | |
97 | movq %rsi, 24(%rsp) | |
98 | movq %rdi, 32(%rsp) | |
99 | movq %r8, 40(%rsp) | |
100 | movq %r9, 48(%rsp) | |
101 | ||
102 | movq 0x38(%rsp), %rdi | |
103 | movq 8(%rbp), %rsi | |
395a59d0 | 104 | subq $MCOUNT_INSN_SIZE, %rdi |
d61f82d0 SR |
105 | |
106 | .globl ftrace_call | |
107 | ftrace_call: | |
108 | call ftrace_stub | |
109 | ||
110 | movq 48(%rsp), %r9 | |
111 | movq 40(%rsp), %r8 | |
112 | movq 32(%rsp), %rdi | |
113 | movq 24(%rsp), %rsi | |
114 | movq 16(%rsp), %rdx | |
115 | movq 8(%rsp), %rcx | |
116 | movq (%rsp), %rax | |
117 | addq $0x38, %rsp | |
118 | ||
119 | .globl ftrace_stub | |
120 | ftrace_stub: | |
121 | retq | |
122 | END(ftrace_caller) | |
123 | ||
124 | #else /* ! CONFIG_DYNAMIC_FTRACE */ | |
16444a8a ACM |
125 | ENTRY(mcount) |
126 | cmpq $ftrace_stub, ftrace_trace_function | |
127 | jnz trace | |
128 | .globl ftrace_stub | |
129 | ftrace_stub: | |
130 | retq | |
131 | ||
132 | trace: | |
133 | /* taken from glibc */ | |
134 | subq $0x38, %rsp | |
135 | movq %rax, (%rsp) | |
136 | movq %rcx, 8(%rsp) | |
137 | movq %rdx, 16(%rsp) | |
138 | movq %rsi, 24(%rsp) | |
139 | movq %rdi, 32(%rsp) | |
140 | movq %r8, 40(%rsp) | |
141 | movq %r9, 48(%rsp) | |
142 | ||
143 | movq 0x38(%rsp), %rdi | |
144 | movq 8(%rbp), %rsi | |
395a59d0 | 145 | subq $MCOUNT_INSN_SIZE, %rdi |
16444a8a ACM |
146 | |
147 | call *ftrace_trace_function | |
148 | ||
149 | movq 48(%rsp), %r9 | |
150 | movq 40(%rsp), %r8 | |
151 | movq 32(%rsp), %rdi | |
152 | movq 24(%rsp), %rsi | |
153 | movq 16(%rsp), %rdx | |
154 | movq 8(%rsp), %rcx | |
155 | movq (%rsp), %rax | |
156 | addq $0x38, %rsp | |
157 | ||
158 | jmp ftrace_stub | |
159 | END(mcount) | |
d61f82d0 SR |
160 | #endif /* CONFIG_DYNAMIC_FTRACE */ |
161 | #endif /* CONFIG_FTRACE */ | |
16444a8a | 162 | |
dc37db4d | 163 | #ifndef CONFIG_PREEMPT |
1da177e4 LT |
164 | #define retint_kernel retint_restore_args |
165 | #endif | |
2601e64d | 166 | |
72fe4858 | 167 | #ifdef CONFIG_PARAVIRT |
2be29982 | 168 | ENTRY(native_usergs_sysret64) |
72fe4858 GOC |
169 | swapgs |
170 | sysretq | |
171 | #endif /* CONFIG_PARAVIRT */ | |
172 | ||
2601e64d IM |
173 | |
174 | .macro TRACE_IRQS_IRETQ offset=ARGOFFSET | |
175 | #ifdef CONFIG_TRACE_IRQFLAGS | |
176 | bt $9,EFLAGS-\offset(%rsp) /* interrupts off? */ | |
177 | jnc 1f | |
178 | TRACE_IRQS_ON | |
179 | 1: | |
180 | #endif | |
181 | .endm | |
182 | ||
1da177e4 LT |
183 | /* |
184 | * C code is not supposed to know about undefined top of stack. Every time | |
185 | * a C function with an pt_regs argument is called from the SYSCALL based | |
186 | * fast path FIXUP_TOP_OF_STACK is needed. | |
187 | * RESTORE_TOP_OF_STACK syncs the syscall state after any possible ptregs | |
188 | * manipulation. | |
189 | */ | |
190 | ||
191 | /* %rsp:at FRAMEEND */ | |
192 | .macro FIXUP_TOP_OF_STACK tmp | |
193 | movq %gs:pda_oldrsp,\tmp | |
194 | movq \tmp,RSP(%rsp) | |
195 | movq $__USER_DS,SS(%rsp) | |
196 | movq $__USER_CS,CS(%rsp) | |
197 | movq $-1,RCX(%rsp) | |
198 | movq R11(%rsp),\tmp /* get eflags */ | |
199 | movq \tmp,EFLAGS(%rsp) | |
200 | .endm | |
201 | ||
202 | .macro RESTORE_TOP_OF_STACK tmp,offset=0 | |
203 | movq RSP-\offset(%rsp),\tmp | |
204 | movq \tmp,%gs:pda_oldrsp | |
205 | movq EFLAGS-\offset(%rsp),\tmp | |
206 | movq \tmp,R11-\offset(%rsp) | |
207 | .endm | |
208 | ||
209 | .macro FAKE_STACK_FRAME child_rip | |
210 | /* push in order ss, rsp, eflags, cs, rip */ | |
3829ee6b | 211 | xorl %eax, %eax |
e04e0a63 | 212 | pushq $__KERNEL_DS /* ss */ |
1da177e4 | 213 | CFI_ADJUST_CFA_OFFSET 8 |
7effaa88 | 214 | /*CFI_REL_OFFSET ss,0*/ |
1da177e4 LT |
215 | pushq %rax /* rsp */ |
216 | CFI_ADJUST_CFA_OFFSET 8 | |
7effaa88 | 217 | CFI_REL_OFFSET rsp,0 |
1da177e4 LT |
218 | pushq $(1<<9) /* eflags - interrupts on */ |
219 | CFI_ADJUST_CFA_OFFSET 8 | |
7effaa88 | 220 | /*CFI_REL_OFFSET rflags,0*/ |
1da177e4 LT |
221 | pushq $__KERNEL_CS /* cs */ |
222 | CFI_ADJUST_CFA_OFFSET 8 | |
7effaa88 | 223 | /*CFI_REL_OFFSET cs,0*/ |
1da177e4 LT |
224 | pushq \child_rip /* rip */ |
225 | CFI_ADJUST_CFA_OFFSET 8 | |
7effaa88 | 226 | CFI_REL_OFFSET rip,0 |
1da177e4 LT |
227 | pushq %rax /* orig rax */ |
228 | CFI_ADJUST_CFA_OFFSET 8 | |
229 | .endm | |
230 | ||
231 | .macro UNFAKE_STACK_FRAME | |
232 | addq $8*6, %rsp | |
233 | CFI_ADJUST_CFA_OFFSET -(6*8) | |
234 | .endm | |
235 | ||
7effaa88 JB |
236 | .macro CFI_DEFAULT_STACK start=1 |
237 | .if \start | |
238 | CFI_STARTPROC simple | |
adf14236 | 239 | CFI_SIGNAL_FRAME |
7effaa88 JB |
240 | CFI_DEF_CFA rsp,SS+8 |
241 | .else | |
242 | CFI_DEF_CFA_OFFSET SS+8 | |
243 | .endif | |
244 | CFI_REL_OFFSET r15,R15 | |
245 | CFI_REL_OFFSET r14,R14 | |
246 | CFI_REL_OFFSET r13,R13 | |
247 | CFI_REL_OFFSET r12,R12 | |
248 | CFI_REL_OFFSET rbp,RBP | |
249 | CFI_REL_OFFSET rbx,RBX | |
250 | CFI_REL_OFFSET r11,R11 | |
251 | CFI_REL_OFFSET r10,R10 | |
252 | CFI_REL_OFFSET r9,R9 | |
253 | CFI_REL_OFFSET r8,R8 | |
254 | CFI_REL_OFFSET rax,RAX | |
255 | CFI_REL_OFFSET rcx,RCX | |
256 | CFI_REL_OFFSET rdx,RDX | |
257 | CFI_REL_OFFSET rsi,RSI | |
258 | CFI_REL_OFFSET rdi,RDI | |
259 | CFI_REL_OFFSET rip,RIP | |
260 | /*CFI_REL_OFFSET cs,CS*/ | |
261 | /*CFI_REL_OFFSET rflags,EFLAGS*/ | |
262 | CFI_REL_OFFSET rsp,RSP | |
263 | /*CFI_REL_OFFSET ss,SS*/ | |
1da177e4 LT |
264 | .endm |
265 | /* | |
266 | * A newly forked process directly context switches into this. | |
267 | */ | |
268 | /* rdi: prev */ | |
269 | ENTRY(ret_from_fork) | |
1da177e4 | 270 | CFI_DEFAULT_STACK |
658fdbef AK |
271 | push kernel_eflags(%rip) |
272 | CFI_ADJUST_CFA_OFFSET 4 | |
273 | popf # reset kernel eflags | |
274 | CFI_ADJUST_CFA_OFFSET -4 | |
1da177e4 LT |
275 | call schedule_tail |
276 | GET_THREAD_INFO(%rcx) | |
26ccb8a7 | 277 | testl $(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT),TI_flags(%rcx) |
1da177e4 LT |
278 | jnz rff_trace |
279 | rff_action: | |
280 | RESTORE_REST | |
281 | testl $3,CS-ARGOFFSET(%rsp) # from kernel_thread? | |
282 | je int_ret_from_sys_call | |
26ccb8a7 | 283 | testl $_TIF_IA32,TI_flags(%rcx) |
1da177e4 LT |
284 | jnz int_ret_from_sys_call |
285 | RESTORE_TOP_OF_STACK %rdi,ARGOFFSET | |
286 | jmp ret_from_sys_call | |
287 | rff_trace: | |
288 | movq %rsp,%rdi | |
289 | call syscall_trace_leave | |
290 | GET_THREAD_INFO(%rcx) | |
291 | jmp rff_action | |
292 | CFI_ENDPROC | |
4b787e0b | 293 | END(ret_from_fork) |
1da177e4 LT |
294 | |
295 | /* | |
296 | * System call entry. Upto 6 arguments in registers are supported. | |
297 | * | |
298 | * SYSCALL does not save anything on the stack and does not change the | |
299 | * stack pointer. | |
300 | */ | |
301 | ||
302 | /* | |
303 | * Register setup: | |
304 | * rax system call number | |
305 | * rdi arg0 | |
306 | * rcx return address for syscall/sysret, C arg3 | |
307 | * rsi arg1 | |
308 | * rdx arg2 | |
309 | * r10 arg3 (--> moved to rcx for C) | |
310 | * r8 arg4 | |
311 | * r9 arg5 | |
312 | * r11 eflags for syscall/sysret, temporary for C | |
313 | * r12-r15,rbp,rbx saved by C code, not touched. | |
314 | * | |
315 | * Interrupts are off on entry. | |
316 | * Only called from user space. | |
317 | * | |
318 | * XXX if we had a free scratch register we could save the RSP into the stack frame | |
319 | * and report it properly in ps. Unfortunately we haven't. | |
7bf36bbc AK |
320 | * |
321 | * When user can change the frames always force IRET. That is because | |
322 | * it deals with uncanonical addresses better. SYSRET has trouble | |
323 | * with them due to bugs in both AMD and Intel CPUs. | |
1da177e4 LT |
324 | */ |
325 | ||
326 | ENTRY(system_call) | |
7effaa88 | 327 | CFI_STARTPROC simple |
adf14236 | 328 | CFI_SIGNAL_FRAME |
dffead4e | 329 | CFI_DEF_CFA rsp,PDA_STACKOFFSET |
7effaa88 JB |
330 | CFI_REGISTER rip,rcx |
331 | /*CFI_REGISTER rflags,r11*/ | |
72fe4858 GOC |
332 | SWAPGS_UNSAFE_STACK |
333 | /* | |
334 | * A hypervisor implementation might want to use a label | |
335 | * after the swapgs, so that it can do the swapgs | |
336 | * for the guest and jump here on syscall. | |
337 | */ | |
338 | ENTRY(system_call_after_swapgs) | |
339 | ||
1da177e4 LT |
340 | movq %rsp,%gs:pda_oldrsp |
341 | movq %gs:pda_kernelstack,%rsp | |
2601e64d IM |
342 | /* |
343 | * No need to follow this irqs off/on section - it's straight | |
344 | * and short: | |
345 | */ | |
72fe4858 | 346 | ENABLE_INTERRUPTS(CLBR_NONE) |
1da177e4 LT |
347 | SAVE_ARGS 8,1 |
348 | movq %rax,ORIG_RAX-ARGOFFSET(%rsp) | |
7effaa88 JB |
349 | movq %rcx,RIP-ARGOFFSET(%rsp) |
350 | CFI_REL_OFFSET rip,RIP-ARGOFFSET | |
1da177e4 | 351 | GET_THREAD_INFO(%rcx) |
d4d67150 | 352 | testl $_TIF_WORK_SYSCALL_ENTRY,TI_flags(%rcx) |
1da177e4 LT |
353 | jnz tracesys |
354 | cmpq $__NR_syscall_max,%rax | |
355 | ja badsys | |
356 | movq %r10,%rcx | |
357 | call *sys_call_table(,%rax,8) # XXX: rip relative | |
358 | movq %rax,RAX-ARGOFFSET(%rsp) | |
359 | /* | |
360 | * Syscall return path ending with SYSRET (fast path) | |
361 | * Has incomplete stack frame and undefined top of stack. | |
362 | */ | |
1da177e4 | 363 | ret_from_sys_call: |
11b854b2 | 364 | movl $_TIF_ALLWORK_MASK,%edi |
1da177e4 LT |
365 | /* edi: flagmask */ |
366 | sysret_check: | |
10cd706d | 367 | LOCKDEP_SYS_EXIT |
1da177e4 | 368 | GET_THREAD_INFO(%rcx) |
72fe4858 | 369 | DISABLE_INTERRUPTS(CLBR_NONE) |
2601e64d | 370 | TRACE_IRQS_OFF |
26ccb8a7 | 371 | movl TI_flags(%rcx),%edx |
1da177e4 LT |
372 | andl %edi,%edx |
373 | jnz sysret_careful | |
bcddc015 | 374 | CFI_REMEMBER_STATE |
2601e64d IM |
375 | /* |
376 | * sysretq will re-enable interrupts: | |
377 | */ | |
378 | TRACE_IRQS_ON | |
1da177e4 | 379 | movq RIP-ARGOFFSET(%rsp),%rcx |
7effaa88 | 380 | CFI_REGISTER rip,rcx |
1da177e4 | 381 | RESTORE_ARGS 0,-ARG_SKIP,1 |
7effaa88 | 382 | /*CFI_REGISTER rflags,r11*/ |
c7245da6 | 383 | movq %gs:pda_oldrsp, %rsp |
2be29982 | 384 | USERGS_SYSRET64 |
1da177e4 | 385 | |
bcddc015 | 386 | CFI_RESTORE_STATE |
1da177e4 LT |
387 | /* Handle reschedules */ |
388 | /* edx: work, edi: workmask */ | |
389 | sysret_careful: | |
390 | bt $TIF_NEED_RESCHED,%edx | |
391 | jnc sysret_signal | |
2601e64d | 392 | TRACE_IRQS_ON |
72fe4858 | 393 | ENABLE_INTERRUPTS(CLBR_NONE) |
1da177e4 | 394 | pushq %rdi |
7effaa88 | 395 | CFI_ADJUST_CFA_OFFSET 8 |
1da177e4 LT |
396 | call schedule |
397 | popq %rdi | |
7effaa88 | 398 | CFI_ADJUST_CFA_OFFSET -8 |
1da177e4 LT |
399 | jmp sysret_check |
400 | ||
401 | /* Handle a signal */ | |
402 | sysret_signal: | |
2601e64d | 403 | TRACE_IRQS_ON |
72fe4858 | 404 | ENABLE_INTERRUPTS(CLBR_NONE) |
8f4d37ec | 405 | testl $_TIF_DO_NOTIFY_MASK,%edx |
10ffdbb8 AK |
406 | jz 1f |
407 | ||
408 | /* Really a signal */ | |
409 | /* edx: work flags (arg3) */ | |
1da177e4 LT |
410 | leaq do_notify_resume(%rip),%rax |
411 | leaq -ARGOFFSET(%rsp),%rdi # &pt_regs -> arg1 | |
412 | xorl %esi,%esi # oldset -> arg2 | |
413 | call ptregscall_common | |
eca91e78 | 414 | 1: movl $_TIF_WORK_MASK,%edi |
7bf36bbc AK |
415 | /* Use IRET because user could have changed frame. This |
416 | works because ptregscall_common has called FIXUP_TOP_OF_STACK. */ | |
72fe4858 | 417 | DISABLE_INTERRUPTS(CLBR_NONE) |
2601e64d | 418 | TRACE_IRQS_OFF |
7bf36bbc | 419 | jmp int_with_check |
1da177e4 | 420 | |
7effaa88 JB |
421 | badsys: |
422 | movq $-ENOSYS,RAX-ARGOFFSET(%rsp) | |
423 | jmp ret_from_sys_call | |
424 | ||
1da177e4 LT |
425 | /* Do syscall tracing */ |
426 | tracesys: | |
427 | SAVE_REST | |
a31f8dd7 | 428 | movq $-ENOSYS,RAX(%rsp) /* ptrace can change this for a bad syscall */ |
1da177e4 LT |
429 | FIXUP_TOP_OF_STACK %rdi |
430 | movq %rsp,%rdi | |
431 | call syscall_trace_enter | |
d4d67150 RM |
432 | /* |
433 | * Reload arg registers from stack in case ptrace changed them. | |
434 | * We don't reload %rax because syscall_trace_enter() returned | |
435 | * the value it wants us to use in the table lookup. | |
436 | */ | |
437 | LOAD_ARGS ARGOFFSET, 1 | |
1da177e4 LT |
438 | RESTORE_REST |
439 | cmpq $__NR_syscall_max,%rax | |
a31f8dd7 | 440 | ja int_ret_from_sys_call /* RAX(%rsp) set to -ENOSYS above */ |
1da177e4 LT |
441 | movq %r10,%rcx /* fixup for C */ |
442 | call *sys_call_table(,%rax,8) | |
a31f8dd7 | 443 | movq %rax,RAX-ARGOFFSET(%rsp) |
7bf36bbc | 444 | /* Use IRET because user could have changed frame */ |
1da177e4 | 445 | |
1da177e4 LT |
446 | /* |
447 | * Syscall return path ending with IRET. | |
448 | * Has correct top of stack, but partial stack frame. | |
bcddc015 JB |
449 | */ |
450 | .globl int_ret_from_sys_call | |
451 | int_ret_from_sys_call: | |
72fe4858 | 452 | DISABLE_INTERRUPTS(CLBR_NONE) |
2601e64d | 453 | TRACE_IRQS_OFF |
1da177e4 LT |
454 | testl $3,CS-ARGOFFSET(%rsp) |
455 | je retint_restore_args | |
456 | movl $_TIF_ALLWORK_MASK,%edi | |
457 | /* edi: mask to check */ | |
458 | int_with_check: | |
10cd706d | 459 | LOCKDEP_SYS_EXIT_IRQ |
1da177e4 | 460 | GET_THREAD_INFO(%rcx) |
26ccb8a7 | 461 | movl TI_flags(%rcx),%edx |
1da177e4 LT |
462 | andl %edi,%edx |
463 | jnz int_careful | |
26ccb8a7 | 464 | andl $~TS_COMPAT,TI_status(%rcx) |
1da177e4 LT |
465 | jmp retint_swapgs |
466 | ||
467 | /* Either reschedule or signal or syscall exit tracking needed. */ | |
468 | /* First do a reschedule test. */ | |
469 | /* edx: work, edi: workmask */ | |
470 | int_careful: | |
471 | bt $TIF_NEED_RESCHED,%edx | |
472 | jnc int_very_careful | |
2601e64d | 473 | TRACE_IRQS_ON |
72fe4858 | 474 | ENABLE_INTERRUPTS(CLBR_NONE) |
1da177e4 | 475 | pushq %rdi |
7effaa88 | 476 | CFI_ADJUST_CFA_OFFSET 8 |
1da177e4 LT |
477 | call schedule |
478 | popq %rdi | |
7effaa88 | 479 | CFI_ADJUST_CFA_OFFSET -8 |
72fe4858 | 480 | DISABLE_INTERRUPTS(CLBR_NONE) |
2601e64d | 481 | TRACE_IRQS_OFF |
1da177e4 LT |
482 | jmp int_with_check |
483 | ||
484 | /* handle signals and tracing -- both require a full stack frame */ | |
485 | int_very_careful: | |
2601e64d | 486 | TRACE_IRQS_ON |
72fe4858 | 487 | ENABLE_INTERRUPTS(CLBR_NONE) |
1da177e4 LT |
488 | SAVE_REST |
489 | /* Check for syscall exit trace */ | |
d4d67150 | 490 | testl $_TIF_WORK_SYSCALL_EXIT,%edx |
1da177e4 LT |
491 | jz int_signal |
492 | pushq %rdi | |
7effaa88 | 493 | CFI_ADJUST_CFA_OFFSET 8 |
1da177e4 LT |
494 | leaq 8(%rsp),%rdi # &ptregs -> arg1 |
495 | call syscall_trace_leave | |
496 | popq %rdi | |
7effaa88 | 497 | CFI_ADJUST_CFA_OFFSET -8 |
d4d67150 | 498 | andl $~(_TIF_WORK_SYSCALL_EXIT|_TIF_SYSCALL_EMU),%edi |
1da177e4 LT |
499 | jmp int_restore_rest |
500 | ||
501 | int_signal: | |
8f4d37ec | 502 | testl $_TIF_DO_NOTIFY_MASK,%edx |
1da177e4 LT |
503 | jz 1f |
504 | movq %rsp,%rdi # &ptregs -> arg1 | |
505 | xorl %esi,%esi # oldset -> arg2 | |
506 | call do_notify_resume | |
eca91e78 | 507 | 1: movl $_TIF_WORK_MASK,%edi |
1da177e4 LT |
508 | int_restore_rest: |
509 | RESTORE_REST | |
72fe4858 | 510 | DISABLE_INTERRUPTS(CLBR_NONE) |
2601e64d | 511 | TRACE_IRQS_OFF |
1da177e4 LT |
512 | jmp int_with_check |
513 | CFI_ENDPROC | |
bcddc015 | 514 | END(system_call) |
1da177e4 LT |
515 | |
516 | /* | |
517 | * Certain special system calls that need to save a complete full stack frame. | |
518 | */ | |
519 | ||
520 | .macro PTREGSCALL label,func,arg | |
521 | .globl \label | |
522 | \label: | |
523 | leaq \func(%rip),%rax | |
524 | leaq -ARGOFFSET+8(%rsp),\arg /* 8 for return address */ | |
525 | jmp ptregscall_common | |
4b787e0b | 526 | END(\label) |
1da177e4 LT |
527 | .endm |
528 | ||
7effaa88 JB |
529 | CFI_STARTPROC |
530 | ||
1da177e4 LT |
531 | PTREGSCALL stub_clone, sys_clone, %r8 |
532 | PTREGSCALL stub_fork, sys_fork, %rdi | |
533 | PTREGSCALL stub_vfork, sys_vfork, %rdi | |
1da177e4 LT |
534 | PTREGSCALL stub_sigaltstack, sys_sigaltstack, %rdx |
535 | PTREGSCALL stub_iopl, sys_iopl, %rsi | |
536 | ||
537 | ENTRY(ptregscall_common) | |
1da177e4 | 538 | popq %r11 |
7effaa88 JB |
539 | CFI_ADJUST_CFA_OFFSET -8 |
540 | CFI_REGISTER rip, r11 | |
1da177e4 LT |
541 | SAVE_REST |
542 | movq %r11, %r15 | |
7effaa88 | 543 | CFI_REGISTER rip, r15 |
1da177e4 LT |
544 | FIXUP_TOP_OF_STACK %r11 |
545 | call *%rax | |
546 | RESTORE_TOP_OF_STACK %r11 | |
547 | movq %r15, %r11 | |
7effaa88 | 548 | CFI_REGISTER rip, r11 |
1da177e4 LT |
549 | RESTORE_REST |
550 | pushq %r11 | |
7effaa88 JB |
551 | CFI_ADJUST_CFA_OFFSET 8 |
552 | CFI_REL_OFFSET rip, 0 | |
1da177e4 LT |
553 | ret |
554 | CFI_ENDPROC | |
4b787e0b | 555 | END(ptregscall_common) |
1da177e4 LT |
556 | |
557 | ENTRY(stub_execve) | |
558 | CFI_STARTPROC | |
559 | popq %r11 | |
7effaa88 JB |
560 | CFI_ADJUST_CFA_OFFSET -8 |
561 | CFI_REGISTER rip, r11 | |
1da177e4 | 562 | SAVE_REST |
1da177e4 | 563 | FIXUP_TOP_OF_STACK %r11 |
5d119b2c | 564 | movq %rsp, %rcx |
1da177e4 | 565 | call sys_execve |
1da177e4 | 566 | RESTORE_TOP_OF_STACK %r11 |
1da177e4 LT |
567 | movq %rax,RAX(%rsp) |
568 | RESTORE_REST | |
569 | jmp int_ret_from_sys_call | |
570 | CFI_ENDPROC | |
4b787e0b | 571 | END(stub_execve) |
1da177e4 LT |
572 | |
573 | /* | |
574 | * sigreturn is special because it needs to restore all registers on return. | |
575 | * This cannot be done with SYSRET, so use the IRET return path instead. | |
576 | */ | |
577 | ENTRY(stub_rt_sigreturn) | |
578 | CFI_STARTPROC | |
7effaa88 JB |
579 | addq $8, %rsp |
580 | CFI_ADJUST_CFA_OFFSET -8 | |
1da177e4 LT |
581 | SAVE_REST |
582 | movq %rsp,%rdi | |
583 | FIXUP_TOP_OF_STACK %r11 | |
584 | call sys_rt_sigreturn | |
585 | movq %rax,RAX(%rsp) # fixme, this could be done at the higher layer | |
586 | RESTORE_REST | |
587 | jmp int_ret_from_sys_call | |
588 | CFI_ENDPROC | |
4b787e0b | 589 | END(stub_rt_sigreturn) |
1da177e4 | 590 | |
7effaa88 JB |
591 | /* |
592 | * initial frame state for interrupts and exceptions | |
593 | */ | |
594 | .macro _frame ref | |
595 | CFI_STARTPROC simple | |
adf14236 | 596 | CFI_SIGNAL_FRAME |
7effaa88 JB |
597 | CFI_DEF_CFA rsp,SS+8-\ref |
598 | /*CFI_REL_OFFSET ss,SS-\ref*/ | |
599 | CFI_REL_OFFSET rsp,RSP-\ref | |
600 | /*CFI_REL_OFFSET rflags,EFLAGS-\ref*/ | |
601 | /*CFI_REL_OFFSET cs,CS-\ref*/ | |
602 | CFI_REL_OFFSET rip,RIP-\ref | |
603 | .endm | |
604 | ||
605 | /* initial frame state for interrupts (and exceptions without error code) */ | |
606 | #define INTR_FRAME _frame RIP | |
607 | /* initial frame state for exceptions with error code (and interrupts with | |
608 | vector already pushed) */ | |
609 | #define XCPT_FRAME _frame ORIG_RAX | |
610 | ||
1da177e4 LT |
611 | /* |
612 | * Interrupt entry/exit. | |
613 | * | |
614 | * Interrupt entry points save only callee clobbered registers in fast path. | |
615 | * | |
616 | * Entry runs with interrupts off. | |
617 | */ | |
618 | ||
619 | /* 0(%rsp): interrupt number */ | |
620 | .macro interrupt func | |
1da177e4 | 621 | cld |
1da177e4 LT |
622 | SAVE_ARGS |
623 | leaq -ARGOFFSET(%rsp),%rdi # arg1 for handler | |
1de9c3f6 JB |
624 | pushq %rbp |
625 | CFI_ADJUST_CFA_OFFSET 8 | |
626 | CFI_REL_OFFSET rbp, 0 | |
627 | movq %rsp,%rbp | |
628 | CFI_DEF_CFA_REGISTER rbp | |
1da177e4 LT |
629 | testl $3,CS(%rdi) |
630 | je 1f | |
72fe4858 | 631 | SWAPGS |
96e54049 AK |
632 | /* irqcount is used to check if a CPU is already on an interrupt |
633 | stack or not. While this is essentially redundant with preempt_count | |
634 | it is a little cheaper to use a separate counter in the PDA | |
635 | (short of moving irq_enter into assembly, which would be too | |
636 | much work) */ | |
637 | 1: incl %gs:pda_irqcount | |
1de9c3f6 | 638 | cmoveq %gs:pda_irqstackptr,%rsp |
2699500b | 639 | push %rbp # backlink for old unwinder |
2601e64d IM |
640 | /* |
641 | * We entered an interrupt context - irqs are off: | |
642 | */ | |
643 | TRACE_IRQS_OFF | |
1da177e4 LT |
644 | call \func |
645 | .endm | |
646 | ||
647 | ENTRY(common_interrupt) | |
7effaa88 | 648 | XCPT_FRAME |
1da177e4 LT |
649 | interrupt do_IRQ |
650 | /* 0(%rsp): oldrsp-ARGOFFSET */ | |
7effaa88 | 651 | ret_from_intr: |
72fe4858 | 652 | DISABLE_INTERRUPTS(CLBR_NONE) |
2601e64d | 653 | TRACE_IRQS_OFF |
3829ee6b | 654 | decl %gs:pda_irqcount |
1de9c3f6 | 655 | leaveq |
7effaa88 | 656 | CFI_DEF_CFA_REGISTER rsp |
1de9c3f6 | 657 | CFI_ADJUST_CFA_OFFSET -8 |
7effaa88 | 658 | exit_intr: |
1da177e4 LT |
659 | GET_THREAD_INFO(%rcx) |
660 | testl $3,CS-ARGOFFSET(%rsp) | |
661 | je retint_kernel | |
662 | ||
663 | /* Interrupt came from user space */ | |
664 | /* | |
665 | * Has a correct top of stack, but a partial stack frame | |
666 | * %rcx: thread info. Interrupts off. | |
667 | */ | |
668 | retint_with_reschedule: | |
669 | movl $_TIF_WORK_MASK,%edi | |
7effaa88 | 670 | retint_check: |
10cd706d | 671 | LOCKDEP_SYS_EXIT_IRQ |
26ccb8a7 | 672 | movl TI_flags(%rcx),%edx |
1da177e4 | 673 | andl %edi,%edx |
7effaa88 | 674 | CFI_REMEMBER_STATE |
1da177e4 | 675 | jnz retint_careful |
10cd706d PZ |
676 | |
677 | retint_swapgs: /* return to user-space */ | |
2601e64d IM |
678 | /* |
679 | * The iretq could re-enable interrupts: | |
680 | */ | |
72fe4858 | 681 | DISABLE_INTERRUPTS(CLBR_ANY) |
2601e64d | 682 | TRACE_IRQS_IRETQ |
72fe4858 | 683 | SWAPGS |
2601e64d IM |
684 | jmp restore_args |
685 | ||
10cd706d | 686 | retint_restore_args: /* return to kernel space */ |
72fe4858 | 687 | DISABLE_INTERRUPTS(CLBR_ANY) |
2601e64d IM |
688 | /* |
689 | * The iretq could re-enable interrupts: | |
690 | */ | |
691 | TRACE_IRQS_IRETQ | |
692 | restore_args: | |
3701d863 IM |
693 | RESTORE_ARGS 0,8,0 |
694 | ||
f7f3d791 | 695 | irq_return: |
72fe4858 | 696 | INTERRUPT_RETURN |
3701d863 IM |
697 | |
698 | .section __ex_table, "a" | |
699 | .quad irq_return, bad_iret | |
700 | .previous | |
701 | ||
702 | #ifdef CONFIG_PARAVIRT | |
72fe4858 | 703 | ENTRY(native_iret) |
1da177e4 LT |
704 | iretq |
705 | ||
706 | .section __ex_table,"a" | |
72fe4858 | 707 | .quad native_iret, bad_iret |
1da177e4 | 708 | .previous |
3701d863 IM |
709 | #endif |
710 | ||
1da177e4 | 711 | .section .fixup,"ax" |
1da177e4 | 712 | bad_iret: |
3aa4b37d RM |
713 | /* |
714 | * The iret traps when the %cs or %ss being restored is bogus. | |
715 | * We've lost the original trap vector and error code. | |
716 | * #GPF is the most likely one to get for an invalid selector. | |
717 | * So pretend we completed the iret and took the #GPF in user mode. | |
718 | * | |
719 | * We are now running with the kernel GS after exception recovery. | |
720 | * But error_entry expects us to have user GS to match the user %cs, | |
721 | * so swap back. | |
722 | */ | |
723 | pushq $0 | |
724 | ||
725 | SWAPGS | |
726 | jmp general_protection | |
727 | ||
72fe4858 GOC |
728 | .previous |
729 | ||
7effaa88 | 730 | /* edi: workmask, edx: work */ |
1da177e4 | 731 | retint_careful: |
7effaa88 | 732 | CFI_RESTORE_STATE |
1da177e4 LT |
733 | bt $TIF_NEED_RESCHED,%edx |
734 | jnc retint_signal | |
2601e64d | 735 | TRACE_IRQS_ON |
72fe4858 | 736 | ENABLE_INTERRUPTS(CLBR_NONE) |
1da177e4 | 737 | pushq %rdi |
7effaa88 | 738 | CFI_ADJUST_CFA_OFFSET 8 |
1da177e4 LT |
739 | call schedule |
740 | popq %rdi | |
7effaa88 | 741 | CFI_ADJUST_CFA_OFFSET -8 |
1da177e4 | 742 | GET_THREAD_INFO(%rcx) |
72fe4858 | 743 | DISABLE_INTERRUPTS(CLBR_NONE) |
2601e64d | 744 | TRACE_IRQS_OFF |
1da177e4 LT |
745 | jmp retint_check |
746 | ||
747 | retint_signal: | |
8f4d37ec | 748 | testl $_TIF_DO_NOTIFY_MASK,%edx |
10ffdbb8 | 749 | jz retint_swapgs |
2601e64d | 750 | TRACE_IRQS_ON |
72fe4858 | 751 | ENABLE_INTERRUPTS(CLBR_NONE) |
1da177e4 LT |
752 | SAVE_REST |
753 | movq $-1,ORIG_RAX(%rsp) | |
3829ee6b | 754 | xorl %esi,%esi # oldset |
1da177e4 LT |
755 | movq %rsp,%rdi # &pt_regs |
756 | call do_notify_resume | |
757 | RESTORE_REST | |
72fe4858 | 758 | DISABLE_INTERRUPTS(CLBR_NONE) |
2601e64d | 759 | TRACE_IRQS_OFF |
be9e6870 | 760 | GET_THREAD_INFO(%rcx) |
eca91e78 | 761 | jmp retint_with_reschedule |
1da177e4 LT |
762 | |
763 | #ifdef CONFIG_PREEMPT | |
764 | /* Returning to kernel space. Check if we need preemption */ | |
765 | /* rcx: threadinfo. interrupts off. */ | |
b06babac | 766 | ENTRY(retint_kernel) |
26ccb8a7 | 767 | cmpl $0,TI_preempt_count(%rcx) |
1da177e4 | 768 | jnz retint_restore_args |
26ccb8a7 | 769 | bt $TIF_NEED_RESCHED,TI_flags(%rcx) |
1da177e4 LT |
770 | jnc retint_restore_args |
771 | bt $9,EFLAGS-ARGOFFSET(%rsp) /* interrupts off? */ | |
772 | jnc retint_restore_args | |
773 | call preempt_schedule_irq | |
774 | jmp exit_intr | |
775 | #endif | |
4b787e0b | 776 | |
1da177e4 | 777 | CFI_ENDPROC |
4b787e0b | 778 | END(common_interrupt) |
1da177e4 LT |
779 | |
780 | /* | |
781 | * APIC interrupts. | |
782 | */ | |
783 | .macro apicinterrupt num,func | |
7effaa88 | 784 | INTR_FRAME |
19eadf98 | 785 | pushq $~(\num) |
7effaa88 | 786 | CFI_ADJUST_CFA_OFFSET 8 |
1da177e4 LT |
787 | interrupt \func |
788 | jmp ret_from_intr | |
789 | CFI_ENDPROC | |
790 | .endm | |
791 | ||
792 | ENTRY(thermal_interrupt) | |
793 | apicinterrupt THERMAL_APIC_VECTOR,smp_thermal_interrupt | |
4b787e0b | 794 | END(thermal_interrupt) |
1da177e4 | 795 | |
89b831ef JS |
796 | ENTRY(threshold_interrupt) |
797 | apicinterrupt THRESHOLD_APIC_VECTOR,mce_threshold_interrupt | |
4b787e0b | 798 | END(threshold_interrupt) |
89b831ef | 799 | |
1da177e4 LT |
800 | #ifdef CONFIG_SMP |
801 | ENTRY(reschedule_interrupt) | |
802 | apicinterrupt RESCHEDULE_VECTOR,smp_reschedule_interrupt | |
4b787e0b | 803 | END(reschedule_interrupt) |
1da177e4 | 804 | |
e5bc8b6b AK |
805 | .macro INVALIDATE_ENTRY num |
806 | ENTRY(invalidate_interrupt\num) | |
807 | apicinterrupt INVALIDATE_TLB_VECTOR_START+\num,smp_invalidate_interrupt | |
4b787e0b | 808 | END(invalidate_interrupt\num) |
e5bc8b6b AK |
809 | .endm |
810 | ||
811 | INVALIDATE_ENTRY 0 | |
812 | INVALIDATE_ENTRY 1 | |
813 | INVALIDATE_ENTRY 2 | |
814 | INVALIDATE_ENTRY 3 | |
815 | INVALIDATE_ENTRY 4 | |
816 | INVALIDATE_ENTRY 5 | |
817 | INVALIDATE_ENTRY 6 | |
818 | INVALIDATE_ENTRY 7 | |
1da177e4 LT |
819 | |
820 | ENTRY(call_function_interrupt) | |
821 | apicinterrupt CALL_FUNCTION_VECTOR,smp_call_function_interrupt | |
4b787e0b | 822 | END(call_function_interrupt) |
3b16cf87 JA |
823 | ENTRY(call_function_single_interrupt) |
824 | apicinterrupt CALL_FUNCTION_SINGLE_VECTOR,smp_call_function_single_interrupt | |
825 | END(call_function_single_interrupt) | |
61014292 EB |
826 | ENTRY(irq_move_cleanup_interrupt) |
827 | apicinterrupt IRQ_MOVE_CLEANUP_VECTOR,smp_irq_move_cleanup_interrupt | |
828 | END(irq_move_cleanup_interrupt) | |
1da177e4 LT |
829 | #endif |
830 | ||
1da177e4 LT |
831 | ENTRY(apic_timer_interrupt) |
832 | apicinterrupt LOCAL_TIMER_VECTOR,smp_apic_timer_interrupt | |
4b787e0b | 833 | END(apic_timer_interrupt) |
1da177e4 | 834 | |
1812924b CW |
835 | ENTRY(uv_bau_message_intr1) |
836 | apicinterrupt 220,uv_bau_message_interrupt | |
837 | END(uv_bau_message_intr1) | |
838 | ||
1da177e4 LT |
839 | ENTRY(error_interrupt) |
840 | apicinterrupt ERROR_APIC_VECTOR,smp_error_interrupt | |
4b787e0b | 841 | END(error_interrupt) |
1da177e4 LT |
842 | |
843 | ENTRY(spurious_interrupt) | |
844 | apicinterrupt SPURIOUS_APIC_VECTOR,smp_spurious_interrupt | |
4b787e0b | 845 | END(spurious_interrupt) |
1da177e4 LT |
846 | |
847 | /* | |
848 | * Exception entry points. | |
849 | */ | |
850 | .macro zeroentry sym | |
7effaa88 | 851 | INTR_FRAME |
fab58420 | 852 | PARAVIRT_ADJUST_EXCEPTION_FRAME |
1da177e4 | 853 | pushq $0 /* push error code/oldrax */ |
7effaa88 | 854 | CFI_ADJUST_CFA_OFFSET 8 |
1da177e4 | 855 | pushq %rax /* push real oldrax to the rdi slot */ |
7effaa88 | 856 | CFI_ADJUST_CFA_OFFSET 8 |
37550907 | 857 | CFI_REL_OFFSET rax,0 |
1da177e4 LT |
858 | leaq \sym(%rip),%rax |
859 | jmp error_entry | |
7effaa88 | 860 | CFI_ENDPROC |
1da177e4 LT |
861 | .endm |
862 | ||
863 | .macro errorentry sym | |
7effaa88 | 864 | XCPT_FRAME |
fab58420 | 865 | PARAVIRT_ADJUST_EXCEPTION_FRAME |
1da177e4 | 866 | pushq %rax |
7effaa88 | 867 | CFI_ADJUST_CFA_OFFSET 8 |
37550907 | 868 | CFI_REL_OFFSET rax,0 |
1da177e4 LT |
869 | leaq \sym(%rip),%rax |
870 | jmp error_entry | |
7effaa88 | 871 | CFI_ENDPROC |
1da177e4 LT |
872 | .endm |
873 | ||
874 | /* error code is on the stack already */ | |
875 | /* handle NMI like exceptions that can happen everywhere */ | |
2601e64d | 876 | .macro paranoidentry sym, ist=0, irqtrace=1 |
1da177e4 LT |
877 | SAVE_ALL |
878 | cld | |
879 | movl $1,%ebx | |
880 | movl $MSR_GS_BASE,%ecx | |
881 | rdmsr | |
882 | testl %edx,%edx | |
883 | js 1f | |
72fe4858 | 884 | SWAPGS |
1da177e4 | 885 | xorl %ebx,%ebx |
b556b35e JB |
886 | 1: |
887 | .if \ist | |
888 | movq %gs:pda_data_offset, %rbp | |
889 | .endif | |
890 | movq %rsp,%rdi | |
1da177e4 LT |
891 | movq ORIG_RAX(%rsp),%rsi |
892 | movq $-1,ORIG_RAX(%rsp) | |
b556b35e | 893 | .if \ist |
5f8efbb9 | 894 | subq $EXCEPTION_STKSZ, per_cpu__init_tss + TSS_ist + (\ist - 1) * 8(%rbp) |
b556b35e | 895 | .endif |
1da177e4 | 896 | call \sym |
b556b35e | 897 | .if \ist |
5f8efbb9 | 898 | addq $EXCEPTION_STKSZ, per_cpu__init_tss + TSS_ist + (\ist - 1) * 8(%rbp) |
b556b35e | 899 | .endif |
72fe4858 | 900 | DISABLE_INTERRUPTS(CLBR_NONE) |
2601e64d IM |
901 | .if \irqtrace |
902 | TRACE_IRQS_OFF | |
903 | .endif | |
1da177e4 | 904 | .endm |
2601e64d IM |
905 | |
906 | /* | |
907 | * "Paranoid" exit path from exception stack. | |
908 | * Paranoid because this is used by NMIs and cannot take | |
909 | * any kernel state for granted. | |
910 | * We don't do kernel preemption checks here, because only | |
911 | * NMI should be common and it does not enable IRQs and | |
912 | * cannot get reschedule ticks. | |
913 | * | |
914 | * "trace" is 0 for the NMI handler only, because irq-tracing | |
915 | * is fundamentally NMI-unsafe. (we cannot change the soft and | |
916 | * hard flags at once, atomically) | |
917 | */ | |
918 | .macro paranoidexit trace=1 | |
919 | /* ebx: no swapgs flag */ | |
920 | paranoid_exit\trace: | |
921 | testl %ebx,%ebx /* swapgs needed? */ | |
922 | jnz paranoid_restore\trace | |
923 | testl $3,CS(%rsp) | |
924 | jnz paranoid_userspace\trace | |
925 | paranoid_swapgs\trace: | |
7a0a2dff | 926 | .if \trace |
2601e64d | 927 | TRACE_IRQS_IRETQ 0 |
7a0a2dff | 928 | .endif |
72fe4858 | 929 | SWAPGS_UNSAFE_STACK |
2601e64d IM |
930 | paranoid_restore\trace: |
931 | RESTORE_ALL 8 | |
3701d863 | 932 | jmp irq_return |
2601e64d IM |
933 | paranoid_userspace\trace: |
934 | GET_THREAD_INFO(%rcx) | |
26ccb8a7 | 935 | movl TI_flags(%rcx),%ebx |
2601e64d IM |
936 | andl $_TIF_WORK_MASK,%ebx |
937 | jz paranoid_swapgs\trace | |
938 | movq %rsp,%rdi /* &pt_regs */ | |
939 | call sync_regs | |
940 | movq %rax,%rsp /* switch stack for scheduling */ | |
941 | testl $_TIF_NEED_RESCHED,%ebx | |
942 | jnz paranoid_schedule\trace | |
943 | movl %ebx,%edx /* arg3: thread flags */ | |
944 | .if \trace | |
945 | TRACE_IRQS_ON | |
946 | .endif | |
72fe4858 | 947 | ENABLE_INTERRUPTS(CLBR_NONE) |
2601e64d IM |
948 | xorl %esi,%esi /* arg2: oldset */ |
949 | movq %rsp,%rdi /* arg1: &pt_regs */ | |
950 | call do_notify_resume | |
72fe4858 | 951 | DISABLE_INTERRUPTS(CLBR_NONE) |
2601e64d IM |
952 | .if \trace |
953 | TRACE_IRQS_OFF | |
954 | .endif | |
955 | jmp paranoid_userspace\trace | |
956 | paranoid_schedule\trace: | |
957 | .if \trace | |
958 | TRACE_IRQS_ON | |
959 | .endif | |
72fe4858 | 960 | ENABLE_INTERRUPTS(CLBR_ANY) |
2601e64d | 961 | call schedule |
72fe4858 | 962 | DISABLE_INTERRUPTS(CLBR_ANY) |
2601e64d IM |
963 | .if \trace |
964 | TRACE_IRQS_OFF | |
965 | .endif | |
966 | jmp paranoid_userspace\trace | |
967 | CFI_ENDPROC | |
968 | .endm | |
969 | ||
1da177e4 LT |
970 | /* |
971 | * Exception entry point. This expects an error code/orig_rax on the stack | |
972 | * and the exception handler in %rax. | |
973 | */ | |
d28c4393 | 974 | KPROBE_ENTRY(error_entry) |
7effaa88 | 975 | _frame RDI |
37550907 | 976 | CFI_REL_OFFSET rax,0 |
1da177e4 LT |
977 | /* rdi slot contains rax, oldrax contains error code */ |
978 | cld | |
979 | subq $14*8,%rsp | |
980 | CFI_ADJUST_CFA_OFFSET (14*8) | |
981 | movq %rsi,13*8(%rsp) | |
982 | CFI_REL_OFFSET rsi,RSI | |
983 | movq 14*8(%rsp),%rsi /* load rax from rdi slot */ | |
37550907 | 984 | CFI_REGISTER rax,rsi |
1da177e4 LT |
985 | movq %rdx,12*8(%rsp) |
986 | CFI_REL_OFFSET rdx,RDX | |
987 | movq %rcx,11*8(%rsp) | |
988 | CFI_REL_OFFSET rcx,RCX | |
989 | movq %rsi,10*8(%rsp) /* store rax */ | |
990 | CFI_REL_OFFSET rax,RAX | |
991 | movq %r8, 9*8(%rsp) | |
992 | CFI_REL_OFFSET r8,R8 | |
993 | movq %r9, 8*8(%rsp) | |
994 | CFI_REL_OFFSET r9,R9 | |
995 | movq %r10,7*8(%rsp) | |
996 | CFI_REL_OFFSET r10,R10 | |
997 | movq %r11,6*8(%rsp) | |
998 | CFI_REL_OFFSET r11,R11 | |
999 | movq %rbx,5*8(%rsp) | |
1000 | CFI_REL_OFFSET rbx,RBX | |
1001 | movq %rbp,4*8(%rsp) | |
1002 | CFI_REL_OFFSET rbp,RBP | |
1003 | movq %r12,3*8(%rsp) | |
1004 | CFI_REL_OFFSET r12,R12 | |
1005 | movq %r13,2*8(%rsp) | |
1006 | CFI_REL_OFFSET r13,R13 | |
1007 | movq %r14,1*8(%rsp) | |
1008 | CFI_REL_OFFSET r14,R14 | |
1009 | movq %r15,(%rsp) | |
1010 | CFI_REL_OFFSET r15,R15 | |
1011 | xorl %ebx,%ebx | |
1012 | testl $3,CS(%rsp) | |
1013 | je error_kernelspace | |
1014 | error_swapgs: | |
72fe4858 | 1015 | SWAPGS |
1da177e4 LT |
1016 | error_sti: |
1017 | movq %rdi,RDI(%rsp) | |
37550907 | 1018 | CFI_REL_OFFSET rdi,RDI |
1da177e4 LT |
1019 | movq %rsp,%rdi |
1020 | movq ORIG_RAX(%rsp),%rsi /* get error code */ | |
1021 | movq $-1,ORIG_RAX(%rsp) | |
1022 | call *%rax | |
10cd706d PZ |
1023 | /* ebx: no swapgs flag (1: don't need swapgs, 0: need it) */ |
1024 | error_exit: | |
1025 | movl %ebx,%eax | |
1da177e4 | 1026 | RESTORE_REST |
72fe4858 | 1027 | DISABLE_INTERRUPTS(CLBR_NONE) |
2601e64d | 1028 | TRACE_IRQS_OFF |
1da177e4 LT |
1029 | GET_THREAD_INFO(%rcx) |
1030 | testl %eax,%eax | |
1031 | jne retint_kernel | |
10cd706d | 1032 | LOCKDEP_SYS_EXIT_IRQ |
26ccb8a7 | 1033 | movl TI_flags(%rcx),%edx |
1da177e4 LT |
1034 | movl $_TIF_WORK_MASK,%edi |
1035 | andl %edi,%edx | |
1036 | jnz retint_careful | |
10cd706d | 1037 | jmp retint_swapgs |
1da177e4 LT |
1038 | CFI_ENDPROC |
1039 | ||
1040 | error_kernelspace: | |
1041 | incl %ebx | |
1042 | /* There are two places in the kernel that can potentially fault with | |
1043 | usergs. Handle them here. The exception handlers after | |
1044 | iret run with kernel gs again, so don't set the user space flag. | |
1045 | B stepping K8s sometimes report an truncated RIP for IRET | |
1046 | exceptions returning to compat mode. Check for these here too. */ | |
9d8ad5d6 VN |
1047 | leaq irq_return(%rip),%rcx |
1048 | cmpq %rcx,RIP(%rsp) | |
1da177e4 | 1049 | je error_swapgs |
9d8ad5d6 VN |
1050 | movl %ecx,%ecx /* zero extend */ |
1051 | cmpq %rcx,RIP(%rsp) | |
1da177e4 LT |
1052 | je error_swapgs |
1053 | cmpq $gs_change,RIP(%rsp) | |
1054 | je error_swapgs | |
1055 | jmp error_sti | |
d28c4393 | 1056 | KPROBE_END(error_entry) |
1da177e4 LT |
1057 | |
1058 | /* Reload gs selector with exception handling */ | |
1059 | /* edi: new selector */ | |
9f9d489a | 1060 | ENTRY(native_load_gs_index) |
7effaa88 | 1061 | CFI_STARTPROC |
1da177e4 | 1062 | pushf |
7effaa88 | 1063 | CFI_ADJUST_CFA_OFFSET 8 |
72fe4858 GOC |
1064 | DISABLE_INTERRUPTS(CLBR_ANY | ~(CLBR_RDI)) |
1065 | SWAPGS | |
1da177e4 LT |
1066 | gs_change: |
1067 | movl %edi,%gs | |
1068 | 2: mfence /* workaround */ | |
72fe4858 | 1069 | SWAPGS |
1da177e4 | 1070 | popf |
7effaa88 | 1071 | CFI_ADJUST_CFA_OFFSET -8 |
1da177e4 | 1072 | ret |
7effaa88 | 1073 | CFI_ENDPROC |
9f9d489a | 1074 | ENDPROC(native_load_gs_index) |
1da177e4 LT |
1075 | |
1076 | .section __ex_table,"a" | |
1077 | .align 8 | |
1078 | .quad gs_change,bad_gs | |
1079 | .previous | |
1080 | .section .fixup,"ax" | |
1081 | /* running with kernelgs */ | |
1082 | bad_gs: | |
72fe4858 | 1083 | SWAPGS /* switch back to user gs */ |
1da177e4 LT |
1084 | xorl %eax,%eax |
1085 | movl %eax,%gs | |
1086 | jmp 2b | |
1087 | .previous | |
1088 | ||
1089 | /* | |
1090 | * Create a kernel thread. | |
1091 | * | |
1092 | * C extern interface: | |
1093 | * extern long kernel_thread(int (*fn)(void *), void * arg, unsigned long flags) | |
1094 | * | |
1095 | * asm input arguments: | |
1096 | * rdi: fn, rsi: arg, rdx: flags | |
1097 | */ | |
1098 | ENTRY(kernel_thread) | |
1099 | CFI_STARTPROC | |
1100 | FAKE_STACK_FRAME $child_rip | |
1101 | SAVE_ALL | |
1102 | ||
1103 | # rdi: flags, rsi: usp, rdx: will be &pt_regs | |
1104 | movq %rdx,%rdi | |
1105 | orq kernel_thread_flags(%rip),%rdi | |
1106 | movq $-1, %rsi | |
1107 | movq %rsp, %rdx | |
1108 | ||
1109 | xorl %r8d,%r8d | |
1110 | xorl %r9d,%r9d | |
1111 | ||
1112 | # clone now | |
1113 | call do_fork | |
1114 | movq %rax,RAX(%rsp) | |
1115 | xorl %edi,%edi | |
1116 | ||
1117 | /* | |
1118 | * It isn't worth to check for reschedule here, | |
1119 | * so internally to the x86_64 port you can rely on kernel_thread() | |
1120 | * not to reschedule the child before returning, this avoids the need | |
1121 | * of hacks for example to fork off the per-CPU idle tasks. | |
1122 | * [Hopefully no generic code relies on the reschedule -AK] | |
1123 | */ | |
1124 | RESTORE_ALL | |
1125 | UNFAKE_STACK_FRAME | |
1126 | ret | |
1127 | CFI_ENDPROC | |
4b787e0b | 1128 | ENDPROC(kernel_thread) |
1da177e4 LT |
1129 | |
1130 | child_rip: | |
c05991ed AK |
1131 | pushq $0 # fake return address |
1132 | CFI_STARTPROC | |
1da177e4 LT |
1133 | /* |
1134 | * Here we are in the child and the registers are set as they were | |
1135 | * at kernel_thread() invocation in the parent. | |
1136 | */ | |
1137 | movq %rdi, %rax | |
1138 | movq %rsi, %rdi | |
1139 | call *%rax | |
1140 | # exit | |
1c5b5cfd | 1141 | mov %eax, %edi |
1da177e4 | 1142 | call do_exit |
c05991ed | 1143 | CFI_ENDPROC |
4b787e0b | 1144 | ENDPROC(child_rip) |
1da177e4 LT |
1145 | |
1146 | /* | |
1147 | * execve(). This function needs to use IRET, not SYSRET, to set up all state properly. | |
1148 | * | |
1149 | * C extern interface: | |
1150 | * extern long execve(char *name, char **argv, char **envp) | |
1151 | * | |
1152 | * asm input arguments: | |
1153 | * rdi: name, rsi: argv, rdx: envp | |
1154 | * | |
1155 | * We want to fallback into: | |
5d119b2c | 1156 | * extern long sys_execve(char *name, char **argv,char **envp, struct pt_regs *regs) |
1da177e4 LT |
1157 | * |
1158 | * do_sys_execve asm fallback arguments: | |
5d119b2c | 1159 | * rdi: name, rsi: argv, rdx: envp, rcx: fake frame on the stack |
1da177e4 | 1160 | */ |
3db03b4a | 1161 | ENTRY(kernel_execve) |
1da177e4 LT |
1162 | CFI_STARTPROC |
1163 | FAKE_STACK_FRAME $0 | |
1164 | SAVE_ALL | |
5d119b2c | 1165 | movq %rsp,%rcx |
1da177e4 LT |
1166 | call sys_execve |
1167 | movq %rax, RAX(%rsp) | |
1168 | RESTORE_REST | |
1169 | testq %rax,%rax | |
1170 | je int_ret_from_sys_call | |
1171 | RESTORE_ARGS | |
1172 | UNFAKE_STACK_FRAME | |
1173 | ret | |
1174 | CFI_ENDPROC | |
3db03b4a | 1175 | ENDPROC(kernel_execve) |
1da177e4 | 1176 | |
0f2fbdcb | 1177 | KPROBE_ENTRY(page_fault) |
1da177e4 | 1178 | errorentry do_page_fault |
d28c4393 | 1179 | KPROBE_END(page_fault) |
1da177e4 LT |
1180 | |
1181 | ENTRY(coprocessor_error) | |
1182 | zeroentry do_coprocessor_error | |
4b787e0b | 1183 | END(coprocessor_error) |
1da177e4 LT |
1184 | |
1185 | ENTRY(simd_coprocessor_error) | |
1186 | zeroentry do_simd_coprocessor_error | |
4b787e0b | 1187 | END(simd_coprocessor_error) |
1da177e4 LT |
1188 | |
1189 | ENTRY(device_not_available) | |
1190 | zeroentry math_state_restore | |
4b787e0b | 1191 | END(device_not_available) |
1da177e4 LT |
1192 | |
1193 | /* runs on exception stack */ | |
0f2fbdcb | 1194 | KPROBE_ENTRY(debug) |
7effaa88 | 1195 | INTR_FRAME |
1da177e4 LT |
1196 | pushq $0 |
1197 | CFI_ADJUST_CFA_OFFSET 8 | |
5f8efbb9 | 1198 | paranoidentry do_debug, DEBUG_STACK |
2601e64d | 1199 | paranoidexit |
d28c4393 | 1200 | KPROBE_END(debug) |
1da177e4 LT |
1201 | |
1202 | /* runs on exception stack */ | |
eddb6fb9 | 1203 | KPROBE_ENTRY(nmi) |
7effaa88 | 1204 | INTR_FRAME |
1da177e4 | 1205 | pushq $-1 |
7effaa88 | 1206 | CFI_ADJUST_CFA_OFFSET 8 |
2601e64d IM |
1207 | paranoidentry do_nmi, 0, 0 |
1208 | #ifdef CONFIG_TRACE_IRQFLAGS | |
1209 | paranoidexit 0 | |
1210 | #else | |
1211 | jmp paranoid_exit1 | |
1212 | CFI_ENDPROC | |
1213 | #endif | |
d28c4393 | 1214 | KPROBE_END(nmi) |
6fefb0d1 | 1215 | |
0f2fbdcb | 1216 | KPROBE_ENTRY(int3) |
b556b35e JB |
1217 | INTR_FRAME |
1218 | pushq $0 | |
1219 | CFI_ADJUST_CFA_OFFSET 8 | |
5f8efbb9 | 1220 | paranoidentry do_int3, DEBUG_STACK |
2601e64d | 1221 | jmp paranoid_exit1 |
b556b35e | 1222 | CFI_ENDPROC |
d28c4393 | 1223 | KPROBE_END(int3) |
1da177e4 LT |
1224 | |
1225 | ENTRY(overflow) | |
1226 | zeroentry do_overflow | |
4b787e0b | 1227 | END(overflow) |
1da177e4 LT |
1228 | |
1229 | ENTRY(bounds) | |
1230 | zeroentry do_bounds | |
4b787e0b | 1231 | END(bounds) |
1da177e4 LT |
1232 | |
1233 | ENTRY(invalid_op) | |
1234 | zeroentry do_invalid_op | |
4b787e0b | 1235 | END(invalid_op) |
1da177e4 LT |
1236 | |
1237 | ENTRY(coprocessor_segment_overrun) | |
1238 | zeroentry do_coprocessor_segment_overrun | |
4b787e0b | 1239 | END(coprocessor_segment_overrun) |
1da177e4 | 1240 | |
1da177e4 LT |
1241 | /* runs on exception stack */ |
1242 | ENTRY(double_fault) | |
7effaa88 | 1243 | XCPT_FRAME |
1da177e4 | 1244 | paranoidentry do_double_fault |
2601e64d | 1245 | jmp paranoid_exit1 |
1da177e4 | 1246 | CFI_ENDPROC |
4b787e0b | 1247 | END(double_fault) |
1da177e4 LT |
1248 | |
1249 | ENTRY(invalid_TSS) | |
1250 | errorentry do_invalid_TSS | |
4b787e0b | 1251 | END(invalid_TSS) |
1da177e4 LT |
1252 | |
1253 | ENTRY(segment_not_present) | |
1254 | errorentry do_segment_not_present | |
4b787e0b | 1255 | END(segment_not_present) |
1da177e4 LT |
1256 | |
1257 | /* runs on exception stack */ | |
1258 | ENTRY(stack_segment) | |
7effaa88 | 1259 | XCPT_FRAME |
1da177e4 | 1260 | paranoidentry do_stack_segment |
2601e64d | 1261 | jmp paranoid_exit1 |
1da177e4 | 1262 | CFI_ENDPROC |
4b787e0b | 1263 | END(stack_segment) |
1da177e4 | 1264 | |
0f2fbdcb | 1265 | KPROBE_ENTRY(general_protection) |
1da177e4 | 1266 | errorentry do_general_protection |
d28c4393 | 1267 | KPROBE_END(general_protection) |
1da177e4 LT |
1268 | |
1269 | ENTRY(alignment_check) | |
1270 | errorentry do_alignment_check | |
4b787e0b | 1271 | END(alignment_check) |
1da177e4 LT |
1272 | |
1273 | ENTRY(divide_error) | |
1274 | zeroentry do_divide_error | |
4b787e0b | 1275 | END(divide_error) |
1da177e4 LT |
1276 | |
1277 | ENTRY(spurious_interrupt_bug) | |
1278 | zeroentry do_spurious_interrupt_bug | |
4b787e0b | 1279 | END(spurious_interrupt_bug) |
1da177e4 LT |
1280 | |
1281 | #ifdef CONFIG_X86_MCE | |
1282 | /* runs on exception stack */ | |
1283 | ENTRY(machine_check) | |
7effaa88 | 1284 | INTR_FRAME |
1da177e4 LT |
1285 | pushq $0 |
1286 | CFI_ADJUST_CFA_OFFSET 8 | |
1287 | paranoidentry do_machine_check | |
2601e64d | 1288 | jmp paranoid_exit1 |
1da177e4 | 1289 | CFI_ENDPROC |
4b787e0b | 1290 | END(machine_check) |
1da177e4 LT |
1291 | #endif |
1292 | ||
2699500b | 1293 | /* Call softirq on interrupt stack. Interrupts are off. */ |
ed6b676c | 1294 | ENTRY(call_softirq) |
7effaa88 | 1295 | CFI_STARTPROC |
2699500b AK |
1296 | push %rbp |
1297 | CFI_ADJUST_CFA_OFFSET 8 | |
1298 | CFI_REL_OFFSET rbp,0 | |
1299 | mov %rsp,%rbp | |
1300 | CFI_DEF_CFA_REGISTER rbp | |
ed6b676c | 1301 | incl %gs:pda_irqcount |
2699500b AK |
1302 | cmove %gs:pda_irqstackptr,%rsp |
1303 | push %rbp # backlink for old unwinder | |
ed6b676c | 1304 | call __do_softirq |
2699500b | 1305 | leaveq |
7effaa88 | 1306 | CFI_DEF_CFA_REGISTER rsp |
2699500b | 1307 | CFI_ADJUST_CFA_OFFSET -8 |
ed6b676c | 1308 | decl %gs:pda_irqcount |
ed6b676c | 1309 | ret |
7effaa88 | 1310 | CFI_ENDPROC |
4b787e0b | 1311 | ENDPROC(call_softirq) |
75154f40 AK |
1312 | |
1313 | KPROBE_ENTRY(ignore_sysret) | |
1314 | CFI_STARTPROC | |
1315 | mov $-ENOSYS,%eax | |
1316 | sysret | |
1317 | CFI_ENDPROC | |
1318 | ENDPROC(ignore_sysret) |