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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> |
72fe4858 | 53 | #include <asm/paravirt.h> |
395a59d0 | 54 | #include <asm/ftrace.h> |
1da177e4 | 55 | |
86a1c34a RM |
56 | /* Avoid __ASSEMBLER__'ifying <linux/audit.h> just for this. */ |
57 | #include <linux/elf-em.h> | |
58 | #define AUDIT_ARCH_X86_64 (EM_X86_64|__AUDIT_ARCH_64BIT|__AUDIT_ARCH_LE) | |
59 | #define __AUDIT_ARCH_64BIT 0x80000000 | |
60 | #define __AUDIT_ARCH_LE 0x40000000 | |
61 | ||
1da177e4 LT |
62 | .code64 |
63 | ||
606576ce | 64 | #ifdef CONFIG_FUNCTION_TRACER |
d61f82d0 SR |
65 | #ifdef CONFIG_DYNAMIC_FTRACE |
66 | ENTRY(mcount) | |
d61f82d0 SR |
67 | retq |
68 | END(mcount) | |
69 | ||
70 | ENTRY(ftrace_caller) | |
60a7ecf4 SR |
71 | cmpl $0, function_trace_stop |
72 | jne ftrace_stub | |
d61f82d0 SR |
73 | |
74 | /* taken from glibc */ | |
75 | subq $0x38, %rsp | |
76 | movq %rax, (%rsp) | |
77 | movq %rcx, 8(%rsp) | |
78 | movq %rdx, 16(%rsp) | |
79 | movq %rsi, 24(%rsp) | |
80 | movq %rdi, 32(%rsp) | |
81 | movq %r8, 40(%rsp) | |
82 | movq %r9, 48(%rsp) | |
83 | ||
84 | movq 0x38(%rsp), %rdi | |
85 | movq 8(%rbp), %rsi | |
395a59d0 | 86 | subq $MCOUNT_INSN_SIZE, %rdi |
d61f82d0 SR |
87 | |
88 | .globl ftrace_call | |
89 | ftrace_call: | |
90 | call ftrace_stub | |
91 | ||
92 | movq 48(%rsp), %r9 | |
93 | movq 40(%rsp), %r8 | |
94 | movq 32(%rsp), %rdi | |
95 | movq 24(%rsp), %rsi | |
96 | movq 16(%rsp), %rdx | |
97 | movq 8(%rsp), %rcx | |
98 | movq (%rsp), %rax | |
99 | addq $0x38, %rsp | |
100 | ||
48d68b20 FW |
101 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
102 | .globl ftrace_graph_call | |
103 | ftrace_graph_call: | |
104 | jmp ftrace_stub | |
105 | #endif | |
106 | ||
d61f82d0 SR |
107 | .globl ftrace_stub |
108 | ftrace_stub: | |
109 | retq | |
110 | END(ftrace_caller) | |
111 | ||
112 | #else /* ! CONFIG_DYNAMIC_FTRACE */ | |
16444a8a | 113 | ENTRY(mcount) |
60a7ecf4 SR |
114 | cmpl $0, function_trace_stop |
115 | jne ftrace_stub | |
116 | ||
16444a8a ACM |
117 | cmpq $ftrace_stub, ftrace_trace_function |
118 | jnz trace | |
48d68b20 FW |
119 | |
120 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER | |
121 | cmpq $ftrace_stub, ftrace_graph_return | |
122 | jnz ftrace_graph_caller | |
e49dc19c SR |
123 | |
124 | cmpq $ftrace_graph_entry_stub, ftrace_graph_entry | |
125 | jnz ftrace_graph_caller | |
48d68b20 FW |
126 | #endif |
127 | ||
16444a8a ACM |
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 | 160 | #endif /* CONFIG_DYNAMIC_FTRACE */ |
606576ce | 161 | #endif /* CONFIG_FUNCTION_TRACER */ |
16444a8a | 162 | |
48d68b20 FW |
163 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
164 | ENTRY(ftrace_graph_caller) | |
165 | cmpl $0, function_trace_stop | |
166 | jne ftrace_stub | |
167 | ||
168 | subq $0x38, %rsp | |
169 | movq %rax, (%rsp) | |
170 | movq %rcx, 8(%rsp) | |
171 | movq %rdx, 16(%rsp) | |
172 | movq %rsi, 24(%rsp) | |
173 | movq %rdi, 32(%rsp) | |
174 | movq %r8, 40(%rsp) | |
175 | movq %r9, 48(%rsp) | |
176 | ||
177 | leaq 8(%rbp), %rdi | |
178 | movq 0x38(%rsp), %rsi | |
bb4304c7 | 179 | subq $MCOUNT_INSN_SIZE, %rsi |
48d68b20 FW |
180 | |
181 | call prepare_ftrace_return | |
182 | ||
183 | movq 48(%rsp), %r9 | |
184 | movq 40(%rsp), %r8 | |
185 | movq 32(%rsp), %rdi | |
186 | movq 24(%rsp), %rsi | |
187 | movq 16(%rsp), %rdx | |
188 | movq 8(%rsp), %rcx | |
189 | movq (%rsp), %rax | |
190 | addq $0x38, %rsp | |
191 | retq | |
192 | END(ftrace_graph_caller) | |
193 | ||
194 | ||
195 | .globl return_to_handler | |
196 | return_to_handler: | |
197 | subq $80, %rsp | |
198 | ||
199 | movq %rax, (%rsp) | |
200 | movq %rcx, 8(%rsp) | |
201 | movq %rdx, 16(%rsp) | |
202 | movq %rsi, 24(%rsp) | |
203 | movq %rdi, 32(%rsp) | |
204 | movq %r8, 40(%rsp) | |
205 | movq %r9, 48(%rsp) | |
206 | movq %r10, 56(%rsp) | |
207 | movq %r11, 64(%rsp) | |
208 | ||
209 | call ftrace_return_to_handler | |
210 | ||
211 | movq %rax, 72(%rsp) | |
212 | movq 64(%rsp), %r11 | |
213 | movq 56(%rsp), %r10 | |
214 | movq 48(%rsp), %r9 | |
215 | movq 40(%rsp), %r8 | |
216 | movq 32(%rsp), %rdi | |
217 | movq 24(%rsp), %rsi | |
218 | movq 16(%rsp), %rdx | |
219 | movq 8(%rsp), %rcx | |
220 | movq (%rsp), %rax | |
221 | addq $72, %rsp | |
222 | retq | |
223 | #endif | |
224 | ||
225 | ||
dc37db4d | 226 | #ifndef CONFIG_PREEMPT |
1da177e4 LT |
227 | #define retint_kernel retint_restore_args |
228 | #endif | |
2601e64d | 229 | |
72fe4858 | 230 | #ifdef CONFIG_PARAVIRT |
2be29982 | 231 | ENTRY(native_usergs_sysret64) |
72fe4858 GOC |
232 | swapgs |
233 | sysretq | |
234 | #endif /* CONFIG_PARAVIRT */ | |
235 | ||
2601e64d IM |
236 | |
237 | .macro TRACE_IRQS_IRETQ offset=ARGOFFSET | |
238 | #ifdef CONFIG_TRACE_IRQFLAGS | |
239 | bt $9,EFLAGS-\offset(%rsp) /* interrupts off? */ | |
240 | jnc 1f | |
241 | TRACE_IRQS_ON | |
242 | 1: | |
243 | #endif | |
244 | .endm | |
245 | ||
1da177e4 LT |
246 | /* |
247 | * C code is not supposed to know about undefined top of stack. Every time | |
248 | * a C function with an pt_regs argument is called from the SYSCALL based | |
249 | * fast path FIXUP_TOP_OF_STACK is needed. | |
250 | * RESTORE_TOP_OF_STACK syncs the syscall state after any possible ptregs | |
251 | * manipulation. | |
252 | */ | |
253 | ||
254 | /* %rsp:at FRAMEEND */ | |
255 | .macro FIXUP_TOP_OF_STACK tmp | |
256 | movq %gs:pda_oldrsp,\tmp | |
257 | movq \tmp,RSP(%rsp) | |
258 | movq $__USER_DS,SS(%rsp) | |
259 | movq $__USER_CS,CS(%rsp) | |
260 | movq $-1,RCX(%rsp) | |
261 | movq R11(%rsp),\tmp /* get eflags */ | |
262 | movq \tmp,EFLAGS(%rsp) | |
263 | .endm | |
264 | ||
265 | .macro RESTORE_TOP_OF_STACK tmp,offset=0 | |
266 | movq RSP-\offset(%rsp),\tmp | |
267 | movq \tmp,%gs:pda_oldrsp | |
268 | movq EFLAGS-\offset(%rsp),\tmp | |
269 | movq \tmp,R11-\offset(%rsp) | |
270 | .endm | |
271 | ||
272 | .macro FAKE_STACK_FRAME child_rip | |
273 | /* push in order ss, rsp, eflags, cs, rip */ | |
3829ee6b | 274 | xorl %eax, %eax |
e04e0a63 | 275 | pushq $__KERNEL_DS /* ss */ |
1da177e4 | 276 | CFI_ADJUST_CFA_OFFSET 8 |
7effaa88 | 277 | /*CFI_REL_OFFSET ss,0*/ |
1da177e4 LT |
278 | pushq %rax /* rsp */ |
279 | CFI_ADJUST_CFA_OFFSET 8 | |
7effaa88 | 280 | CFI_REL_OFFSET rsp,0 |
1da177e4 LT |
281 | pushq $(1<<9) /* eflags - interrupts on */ |
282 | CFI_ADJUST_CFA_OFFSET 8 | |
7effaa88 | 283 | /*CFI_REL_OFFSET rflags,0*/ |
1da177e4 LT |
284 | pushq $__KERNEL_CS /* cs */ |
285 | CFI_ADJUST_CFA_OFFSET 8 | |
7effaa88 | 286 | /*CFI_REL_OFFSET cs,0*/ |
1da177e4 LT |
287 | pushq \child_rip /* rip */ |
288 | CFI_ADJUST_CFA_OFFSET 8 | |
7effaa88 | 289 | CFI_REL_OFFSET rip,0 |
1da177e4 LT |
290 | pushq %rax /* orig rax */ |
291 | CFI_ADJUST_CFA_OFFSET 8 | |
292 | .endm | |
293 | ||
294 | .macro UNFAKE_STACK_FRAME | |
295 | addq $8*6, %rsp | |
296 | CFI_ADJUST_CFA_OFFSET -(6*8) | |
297 | .endm | |
298 | ||
7effaa88 JB |
299 | .macro CFI_DEFAULT_STACK start=1 |
300 | .if \start | |
301 | CFI_STARTPROC simple | |
adf14236 | 302 | CFI_SIGNAL_FRAME |
7effaa88 JB |
303 | CFI_DEF_CFA rsp,SS+8 |
304 | .else | |
305 | CFI_DEF_CFA_OFFSET SS+8 | |
306 | .endif | |
307 | CFI_REL_OFFSET r15,R15 | |
308 | CFI_REL_OFFSET r14,R14 | |
309 | CFI_REL_OFFSET r13,R13 | |
310 | CFI_REL_OFFSET r12,R12 | |
311 | CFI_REL_OFFSET rbp,RBP | |
312 | CFI_REL_OFFSET rbx,RBX | |
313 | CFI_REL_OFFSET r11,R11 | |
314 | CFI_REL_OFFSET r10,R10 | |
315 | CFI_REL_OFFSET r9,R9 | |
316 | CFI_REL_OFFSET r8,R8 | |
317 | CFI_REL_OFFSET rax,RAX | |
318 | CFI_REL_OFFSET rcx,RCX | |
319 | CFI_REL_OFFSET rdx,RDX | |
320 | CFI_REL_OFFSET rsi,RSI | |
321 | CFI_REL_OFFSET rdi,RDI | |
322 | CFI_REL_OFFSET rip,RIP | |
323 | /*CFI_REL_OFFSET cs,CS*/ | |
324 | /*CFI_REL_OFFSET rflags,EFLAGS*/ | |
325 | CFI_REL_OFFSET rsp,RSP | |
326 | /*CFI_REL_OFFSET ss,SS*/ | |
1da177e4 LT |
327 | .endm |
328 | /* | |
329 | * A newly forked process directly context switches into this. | |
330 | */ | |
331 | /* rdi: prev */ | |
332 | ENTRY(ret_from_fork) | |
1da177e4 | 333 | CFI_DEFAULT_STACK |
658fdbef | 334 | push kernel_eflags(%rip) |
e0a5a5d9 | 335 | CFI_ADJUST_CFA_OFFSET 8 |
658fdbef | 336 | popf # reset kernel eflags |
e0a5a5d9 | 337 | CFI_ADJUST_CFA_OFFSET -8 |
1da177e4 LT |
338 | call schedule_tail |
339 | GET_THREAD_INFO(%rcx) | |
26ccb8a7 | 340 | testl $(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT),TI_flags(%rcx) |
1da177e4 LT |
341 | jnz rff_trace |
342 | rff_action: | |
343 | RESTORE_REST | |
344 | testl $3,CS-ARGOFFSET(%rsp) # from kernel_thread? | |
345 | je int_ret_from_sys_call | |
26ccb8a7 | 346 | testl $_TIF_IA32,TI_flags(%rcx) |
1da177e4 LT |
347 | jnz int_ret_from_sys_call |
348 | RESTORE_TOP_OF_STACK %rdi,ARGOFFSET | |
349 | jmp ret_from_sys_call | |
350 | rff_trace: | |
351 | movq %rsp,%rdi | |
352 | call syscall_trace_leave | |
353 | GET_THREAD_INFO(%rcx) | |
354 | jmp rff_action | |
355 | CFI_ENDPROC | |
4b787e0b | 356 | END(ret_from_fork) |
1da177e4 LT |
357 | |
358 | /* | |
359 | * System call entry. Upto 6 arguments in registers are supported. | |
360 | * | |
361 | * SYSCALL does not save anything on the stack and does not change the | |
362 | * stack pointer. | |
363 | */ | |
364 | ||
365 | /* | |
366 | * Register setup: | |
367 | * rax system call number | |
368 | * rdi arg0 | |
369 | * rcx return address for syscall/sysret, C arg3 | |
370 | * rsi arg1 | |
371 | * rdx arg2 | |
372 | * r10 arg3 (--> moved to rcx for C) | |
373 | * r8 arg4 | |
374 | * r9 arg5 | |
375 | * r11 eflags for syscall/sysret, temporary for C | |
376 | * r12-r15,rbp,rbx saved by C code, not touched. | |
377 | * | |
378 | * Interrupts are off on entry. | |
379 | * Only called from user space. | |
380 | * | |
381 | * XXX if we had a free scratch register we could save the RSP into the stack frame | |
382 | * and report it properly in ps. Unfortunately we haven't. | |
7bf36bbc AK |
383 | * |
384 | * When user can change the frames always force IRET. That is because | |
385 | * it deals with uncanonical addresses better. SYSRET has trouble | |
386 | * with them due to bugs in both AMD and Intel CPUs. | |
1da177e4 LT |
387 | */ |
388 | ||
389 | ENTRY(system_call) | |
7effaa88 | 390 | CFI_STARTPROC simple |
adf14236 | 391 | CFI_SIGNAL_FRAME |
dffead4e | 392 | CFI_DEF_CFA rsp,PDA_STACKOFFSET |
7effaa88 JB |
393 | CFI_REGISTER rip,rcx |
394 | /*CFI_REGISTER rflags,r11*/ | |
72fe4858 GOC |
395 | SWAPGS_UNSAFE_STACK |
396 | /* | |
397 | * A hypervisor implementation might want to use a label | |
398 | * after the swapgs, so that it can do the swapgs | |
399 | * for the guest and jump here on syscall. | |
400 | */ | |
401 | ENTRY(system_call_after_swapgs) | |
402 | ||
1da177e4 LT |
403 | movq %rsp,%gs:pda_oldrsp |
404 | movq %gs:pda_kernelstack,%rsp | |
2601e64d IM |
405 | /* |
406 | * No need to follow this irqs off/on section - it's straight | |
407 | * and short: | |
408 | */ | |
72fe4858 | 409 | ENABLE_INTERRUPTS(CLBR_NONE) |
1da177e4 LT |
410 | SAVE_ARGS 8,1 |
411 | movq %rax,ORIG_RAX-ARGOFFSET(%rsp) | |
7effaa88 JB |
412 | movq %rcx,RIP-ARGOFFSET(%rsp) |
413 | CFI_REL_OFFSET rip,RIP-ARGOFFSET | |
1da177e4 | 414 | GET_THREAD_INFO(%rcx) |
d4d67150 | 415 | testl $_TIF_WORK_SYSCALL_ENTRY,TI_flags(%rcx) |
1da177e4 | 416 | jnz tracesys |
86a1c34a | 417 | system_call_fastpath: |
1da177e4 LT |
418 | cmpq $__NR_syscall_max,%rax |
419 | ja badsys | |
420 | movq %r10,%rcx | |
421 | call *sys_call_table(,%rax,8) # XXX: rip relative | |
422 | movq %rax,RAX-ARGOFFSET(%rsp) | |
423 | /* | |
424 | * Syscall return path ending with SYSRET (fast path) | |
425 | * Has incomplete stack frame and undefined top of stack. | |
426 | */ | |
1da177e4 | 427 | ret_from_sys_call: |
11b854b2 | 428 | movl $_TIF_ALLWORK_MASK,%edi |
1da177e4 LT |
429 | /* edi: flagmask */ |
430 | sysret_check: | |
10cd706d | 431 | LOCKDEP_SYS_EXIT |
1da177e4 | 432 | GET_THREAD_INFO(%rcx) |
72fe4858 | 433 | DISABLE_INTERRUPTS(CLBR_NONE) |
2601e64d | 434 | TRACE_IRQS_OFF |
26ccb8a7 | 435 | movl TI_flags(%rcx),%edx |
1da177e4 LT |
436 | andl %edi,%edx |
437 | jnz sysret_careful | |
bcddc015 | 438 | CFI_REMEMBER_STATE |
2601e64d IM |
439 | /* |
440 | * sysretq will re-enable interrupts: | |
441 | */ | |
442 | TRACE_IRQS_ON | |
1da177e4 | 443 | movq RIP-ARGOFFSET(%rsp),%rcx |
7effaa88 | 444 | CFI_REGISTER rip,rcx |
1da177e4 | 445 | RESTORE_ARGS 0,-ARG_SKIP,1 |
7effaa88 | 446 | /*CFI_REGISTER rflags,r11*/ |
c7245da6 | 447 | movq %gs:pda_oldrsp, %rsp |
2be29982 | 448 | USERGS_SYSRET64 |
1da177e4 | 449 | |
bcddc015 | 450 | CFI_RESTORE_STATE |
1da177e4 LT |
451 | /* Handle reschedules */ |
452 | /* edx: work, edi: workmask */ | |
453 | sysret_careful: | |
454 | bt $TIF_NEED_RESCHED,%edx | |
455 | jnc sysret_signal | |
2601e64d | 456 | TRACE_IRQS_ON |
72fe4858 | 457 | ENABLE_INTERRUPTS(CLBR_NONE) |
1da177e4 | 458 | pushq %rdi |
7effaa88 | 459 | CFI_ADJUST_CFA_OFFSET 8 |
1da177e4 LT |
460 | call schedule |
461 | popq %rdi | |
7effaa88 | 462 | CFI_ADJUST_CFA_OFFSET -8 |
1da177e4 LT |
463 | jmp sysret_check |
464 | ||
465 | /* Handle a signal */ | |
466 | sysret_signal: | |
2601e64d | 467 | TRACE_IRQS_ON |
72fe4858 | 468 | ENABLE_INTERRUPTS(CLBR_NONE) |
86a1c34a RM |
469 | #ifdef CONFIG_AUDITSYSCALL |
470 | bt $TIF_SYSCALL_AUDIT,%edx | |
471 | jc sysret_audit | |
472 | #endif | |
10ffdbb8 | 473 | /* edx: work flags (arg3) */ |
1da177e4 LT |
474 | leaq do_notify_resume(%rip),%rax |
475 | leaq -ARGOFFSET(%rsp),%rdi # &pt_regs -> arg1 | |
476 | xorl %esi,%esi # oldset -> arg2 | |
477 | call ptregscall_common | |
15e8f348 | 478 | movl $_TIF_WORK_MASK,%edi |
7bf36bbc AK |
479 | /* Use IRET because user could have changed frame. This |
480 | works because ptregscall_common has called FIXUP_TOP_OF_STACK. */ | |
72fe4858 | 481 | DISABLE_INTERRUPTS(CLBR_NONE) |
2601e64d | 482 | TRACE_IRQS_OFF |
7bf36bbc | 483 | jmp int_with_check |
1da177e4 | 484 | |
7effaa88 JB |
485 | badsys: |
486 | movq $-ENOSYS,RAX-ARGOFFSET(%rsp) | |
487 | jmp ret_from_sys_call | |
488 | ||
86a1c34a RM |
489 | #ifdef CONFIG_AUDITSYSCALL |
490 | /* | |
491 | * Fast path for syscall audit without full syscall trace. | |
492 | * We just call audit_syscall_entry() directly, and then | |
493 | * jump back to the normal fast path. | |
494 | */ | |
495 | auditsys: | |
496 | movq %r10,%r9 /* 6th arg: 4th syscall arg */ | |
497 | movq %rdx,%r8 /* 5th arg: 3rd syscall arg */ | |
498 | movq %rsi,%rcx /* 4th arg: 2nd syscall arg */ | |
499 | movq %rdi,%rdx /* 3rd arg: 1st syscall arg */ | |
500 | movq %rax,%rsi /* 2nd arg: syscall number */ | |
501 | movl $AUDIT_ARCH_X86_64,%edi /* 1st arg: audit arch */ | |
502 | call audit_syscall_entry | |
503 | LOAD_ARGS 0 /* reload call-clobbered registers */ | |
504 | jmp system_call_fastpath | |
505 | ||
506 | /* | |
507 | * Return fast path for syscall audit. Call audit_syscall_exit() | |
508 | * directly and then jump back to the fast path with TIF_SYSCALL_AUDIT | |
509 | * masked off. | |
510 | */ | |
511 | sysret_audit: | |
512 | movq %rax,%rsi /* second arg, syscall return value */ | |
513 | cmpq $0,%rax /* is it < 0? */ | |
514 | setl %al /* 1 if so, 0 if not */ | |
515 | movzbl %al,%edi /* zero-extend that into %edi */ | |
516 | inc %edi /* first arg, 0->1(AUDITSC_SUCCESS), 1->2(AUDITSC_FAILURE) */ | |
517 | call audit_syscall_exit | |
518 | movl $(_TIF_ALLWORK_MASK & ~_TIF_SYSCALL_AUDIT),%edi | |
519 | jmp sysret_check | |
520 | #endif /* CONFIG_AUDITSYSCALL */ | |
521 | ||
1da177e4 LT |
522 | /* Do syscall tracing */ |
523 | tracesys: | |
86a1c34a RM |
524 | #ifdef CONFIG_AUDITSYSCALL |
525 | testl $(_TIF_WORK_SYSCALL_ENTRY & ~_TIF_SYSCALL_AUDIT),TI_flags(%rcx) | |
526 | jz auditsys | |
527 | #endif | |
1da177e4 | 528 | SAVE_REST |
a31f8dd7 | 529 | movq $-ENOSYS,RAX(%rsp) /* ptrace can change this for a bad syscall */ |
1da177e4 LT |
530 | FIXUP_TOP_OF_STACK %rdi |
531 | movq %rsp,%rdi | |
532 | call syscall_trace_enter | |
d4d67150 RM |
533 | /* |
534 | * Reload arg registers from stack in case ptrace changed them. | |
535 | * We don't reload %rax because syscall_trace_enter() returned | |
536 | * the value it wants us to use in the table lookup. | |
537 | */ | |
538 | LOAD_ARGS ARGOFFSET, 1 | |
1da177e4 LT |
539 | RESTORE_REST |
540 | cmpq $__NR_syscall_max,%rax | |
a31f8dd7 | 541 | ja int_ret_from_sys_call /* RAX(%rsp) set to -ENOSYS above */ |
1da177e4 LT |
542 | movq %r10,%rcx /* fixup for C */ |
543 | call *sys_call_table(,%rax,8) | |
a31f8dd7 | 544 | movq %rax,RAX-ARGOFFSET(%rsp) |
7bf36bbc | 545 | /* Use IRET because user could have changed frame */ |
1da177e4 | 546 | |
1da177e4 LT |
547 | /* |
548 | * Syscall return path ending with IRET. | |
549 | * Has correct top of stack, but partial stack frame. | |
bcddc015 JB |
550 | */ |
551 | .globl int_ret_from_sys_call | |
5cbf1565 | 552 | .globl int_with_check |
bcddc015 | 553 | int_ret_from_sys_call: |
72fe4858 | 554 | DISABLE_INTERRUPTS(CLBR_NONE) |
2601e64d | 555 | TRACE_IRQS_OFF |
1da177e4 LT |
556 | testl $3,CS-ARGOFFSET(%rsp) |
557 | je retint_restore_args | |
558 | movl $_TIF_ALLWORK_MASK,%edi | |
559 | /* edi: mask to check */ | |
560 | int_with_check: | |
10cd706d | 561 | LOCKDEP_SYS_EXIT_IRQ |
1da177e4 | 562 | GET_THREAD_INFO(%rcx) |
26ccb8a7 | 563 | movl TI_flags(%rcx),%edx |
1da177e4 LT |
564 | andl %edi,%edx |
565 | jnz int_careful | |
26ccb8a7 | 566 | andl $~TS_COMPAT,TI_status(%rcx) |
1da177e4 LT |
567 | jmp retint_swapgs |
568 | ||
569 | /* Either reschedule or signal or syscall exit tracking needed. */ | |
570 | /* First do a reschedule test. */ | |
571 | /* edx: work, edi: workmask */ | |
572 | int_careful: | |
573 | bt $TIF_NEED_RESCHED,%edx | |
574 | jnc int_very_careful | |
2601e64d | 575 | TRACE_IRQS_ON |
72fe4858 | 576 | ENABLE_INTERRUPTS(CLBR_NONE) |
1da177e4 | 577 | pushq %rdi |
7effaa88 | 578 | CFI_ADJUST_CFA_OFFSET 8 |
1da177e4 LT |
579 | call schedule |
580 | popq %rdi | |
7effaa88 | 581 | CFI_ADJUST_CFA_OFFSET -8 |
72fe4858 | 582 | DISABLE_INTERRUPTS(CLBR_NONE) |
2601e64d | 583 | TRACE_IRQS_OFF |
1da177e4 LT |
584 | jmp int_with_check |
585 | ||
586 | /* handle signals and tracing -- both require a full stack frame */ | |
587 | int_very_careful: | |
2601e64d | 588 | TRACE_IRQS_ON |
72fe4858 | 589 | ENABLE_INTERRUPTS(CLBR_NONE) |
1da177e4 LT |
590 | SAVE_REST |
591 | /* Check for syscall exit trace */ | |
d4d67150 | 592 | testl $_TIF_WORK_SYSCALL_EXIT,%edx |
1da177e4 LT |
593 | jz int_signal |
594 | pushq %rdi | |
7effaa88 | 595 | CFI_ADJUST_CFA_OFFSET 8 |
1da177e4 LT |
596 | leaq 8(%rsp),%rdi # &ptregs -> arg1 |
597 | call syscall_trace_leave | |
598 | popq %rdi | |
7effaa88 | 599 | CFI_ADJUST_CFA_OFFSET -8 |
d4d67150 | 600 | andl $~(_TIF_WORK_SYSCALL_EXIT|_TIF_SYSCALL_EMU),%edi |
1da177e4 LT |
601 | jmp int_restore_rest |
602 | ||
603 | int_signal: | |
8f4d37ec | 604 | testl $_TIF_DO_NOTIFY_MASK,%edx |
1da177e4 LT |
605 | jz 1f |
606 | movq %rsp,%rdi # &ptregs -> arg1 | |
607 | xorl %esi,%esi # oldset -> arg2 | |
608 | call do_notify_resume | |
eca91e78 | 609 | 1: movl $_TIF_WORK_MASK,%edi |
1da177e4 LT |
610 | int_restore_rest: |
611 | RESTORE_REST | |
72fe4858 | 612 | DISABLE_INTERRUPTS(CLBR_NONE) |
2601e64d | 613 | TRACE_IRQS_OFF |
1da177e4 LT |
614 | jmp int_with_check |
615 | CFI_ENDPROC | |
bcddc015 | 616 | END(system_call) |
1da177e4 LT |
617 | |
618 | /* | |
619 | * Certain special system calls that need to save a complete full stack frame. | |
620 | */ | |
621 | ||
622 | .macro PTREGSCALL label,func,arg | |
623 | .globl \label | |
624 | \label: | |
625 | leaq \func(%rip),%rax | |
626 | leaq -ARGOFFSET+8(%rsp),\arg /* 8 for return address */ | |
627 | jmp ptregscall_common | |
4b787e0b | 628 | END(\label) |
1da177e4 LT |
629 | .endm |
630 | ||
7effaa88 JB |
631 | CFI_STARTPROC |
632 | ||
1da177e4 LT |
633 | PTREGSCALL stub_clone, sys_clone, %r8 |
634 | PTREGSCALL stub_fork, sys_fork, %rdi | |
635 | PTREGSCALL stub_vfork, sys_vfork, %rdi | |
1da177e4 LT |
636 | PTREGSCALL stub_sigaltstack, sys_sigaltstack, %rdx |
637 | PTREGSCALL stub_iopl, sys_iopl, %rsi | |
638 | ||
639 | ENTRY(ptregscall_common) | |
1da177e4 | 640 | popq %r11 |
7effaa88 JB |
641 | CFI_ADJUST_CFA_OFFSET -8 |
642 | CFI_REGISTER rip, r11 | |
1da177e4 LT |
643 | SAVE_REST |
644 | movq %r11, %r15 | |
7effaa88 | 645 | CFI_REGISTER rip, r15 |
1da177e4 LT |
646 | FIXUP_TOP_OF_STACK %r11 |
647 | call *%rax | |
648 | RESTORE_TOP_OF_STACK %r11 | |
649 | movq %r15, %r11 | |
7effaa88 | 650 | CFI_REGISTER rip, r11 |
1da177e4 LT |
651 | RESTORE_REST |
652 | pushq %r11 | |
7effaa88 JB |
653 | CFI_ADJUST_CFA_OFFSET 8 |
654 | CFI_REL_OFFSET rip, 0 | |
1da177e4 LT |
655 | ret |
656 | CFI_ENDPROC | |
4b787e0b | 657 | END(ptregscall_common) |
1da177e4 LT |
658 | |
659 | ENTRY(stub_execve) | |
660 | CFI_STARTPROC | |
661 | popq %r11 | |
7effaa88 JB |
662 | CFI_ADJUST_CFA_OFFSET -8 |
663 | CFI_REGISTER rip, r11 | |
1da177e4 | 664 | SAVE_REST |
1da177e4 | 665 | FIXUP_TOP_OF_STACK %r11 |
5d119b2c | 666 | movq %rsp, %rcx |
1da177e4 | 667 | call sys_execve |
1da177e4 | 668 | RESTORE_TOP_OF_STACK %r11 |
1da177e4 LT |
669 | movq %rax,RAX(%rsp) |
670 | RESTORE_REST | |
671 | jmp int_ret_from_sys_call | |
672 | CFI_ENDPROC | |
4b787e0b | 673 | END(stub_execve) |
1da177e4 LT |
674 | |
675 | /* | |
676 | * sigreturn is special because it needs to restore all registers on return. | |
677 | * This cannot be done with SYSRET, so use the IRET return path instead. | |
678 | */ | |
679 | ENTRY(stub_rt_sigreturn) | |
680 | CFI_STARTPROC | |
7effaa88 JB |
681 | addq $8, %rsp |
682 | CFI_ADJUST_CFA_OFFSET -8 | |
1da177e4 LT |
683 | SAVE_REST |
684 | movq %rsp,%rdi | |
685 | FIXUP_TOP_OF_STACK %r11 | |
686 | call sys_rt_sigreturn | |
687 | movq %rax,RAX(%rsp) # fixme, this could be done at the higher layer | |
688 | RESTORE_REST | |
689 | jmp int_ret_from_sys_call | |
690 | CFI_ENDPROC | |
4b787e0b | 691 | END(stub_rt_sigreturn) |
1da177e4 | 692 | |
7effaa88 JB |
693 | /* |
694 | * initial frame state for interrupts and exceptions | |
695 | */ | |
696 | .macro _frame ref | |
697 | CFI_STARTPROC simple | |
adf14236 | 698 | CFI_SIGNAL_FRAME |
7effaa88 JB |
699 | CFI_DEF_CFA rsp,SS+8-\ref |
700 | /*CFI_REL_OFFSET ss,SS-\ref*/ | |
701 | CFI_REL_OFFSET rsp,RSP-\ref | |
702 | /*CFI_REL_OFFSET rflags,EFLAGS-\ref*/ | |
703 | /*CFI_REL_OFFSET cs,CS-\ref*/ | |
704 | CFI_REL_OFFSET rip,RIP-\ref | |
705 | .endm | |
706 | ||
707 | /* initial frame state for interrupts (and exceptions without error code) */ | |
708 | #define INTR_FRAME _frame RIP | |
709 | /* initial frame state for exceptions with error code (and interrupts with | |
710 | vector already pushed) */ | |
711 | #define XCPT_FRAME _frame ORIG_RAX | |
712 | ||
1da177e4 LT |
713 | /* |
714 | * Interrupt entry/exit. | |
715 | * | |
716 | * Interrupt entry points save only callee clobbered registers in fast path. | |
717 | * | |
718 | * Entry runs with interrupts off. | |
719 | */ | |
720 | ||
721 | /* 0(%rsp): interrupt number */ | |
722 | .macro interrupt func | |
1da177e4 | 723 | cld |
1da177e4 LT |
724 | SAVE_ARGS |
725 | leaq -ARGOFFSET(%rsp),%rdi # arg1 for handler | |
1de9c3f6 | 726 | pushq %rbp |
097a0788 GC |
727 | /* |
728 | * Save rbp twice: One is for marking the stack frame, as usual, and the | |
729 | * other, to fill pt_regs properly. This is because bx comes right | |
730 | * before the last saved register in that structure, and not bp. If the | |
731 | * base pointer were in the place bx is today, this would not be needed. | |
732 | */ | |
733 | movq %rbp, -8(%rsp) | |
1de9c3f6 JB |
734 | CFI_ADJUST_CFA_OFFSET 8 |
735 | CFI_REL_OFFSET rbp, 0 | |
736 | movq %rsp,%rbp | |
737 | CFI_DEF_CFA_REGISTER rbp | |
1da177e4 LT |
738 | testl $3,CS(%rdi) |
739 | je 1f | |
72fe4858 | 740 | SWAPGS |
96e54049 AK |
741 | /* irqcount is used to check if a CPU is already on an interrupt |
742 | stack or not. While this is essentially redundant with preempt_count | |
743 | it is a little cheaper to use a separate counter in the PDA | |
744 | (short of moving irq_enter into assembly, which would be too | |
745 | much work) */ | |
746 | 1: incl %gs:pda_irqcount | |
1de9c3f6 | 747 | cmoveq %gs:pda_irqstackptr,%rsp |
2699500b | 748 | push %rbp # backlink for old unwinder |
2601e64d IM |
749 | /* |
750 | * We entered an interrupt context - irqs are off: | |
751 | */ | |
752 | TRACE_IRQS_OFF | |
1da177e4 LT |
753 | call \func |
754 | .endm | |
755 | ||
756 | ENTRY(common_interrupt) | |
7effaa88 | 757 | XCPT_FRAME |
1da177e4 LT |
758 | interrupt do_IRQ |
759 | /* 0(%rsp): oldrsp-ARGOFFSET */ | |
7effaa88 | 760 | ret_from_intr: |
72fe4858 | 761 | DISABLE_INTERRUPTS(CLBR_NONE) |
2601e64d | 762 | TRACE_IRQS_OFF |
3829ee6b | 763 | decl %gs:pda_irqcount |
1de9c3f6 | 764 | leaveq |
7effaa88 | 765 | CFI_DEF_CFA_REGISTER rsp |
1de9c3f6 | 766 | CFI_ADJUST_CFA_OFFSET -8 |
7effaa88 | 767 | exit_intr: |
1da177e4 LT |
768 | GET_THREAD_INFO(%rcx) |
769 | testl $3,CS-ARGOFFSET(%rsp) | |
770 | je retint_kernel | |
771 | ||
772 | /* Interrupt came from user space */ | |
773 | /* | |
774 | * Has a correct top of stack, but a partial stack frame | |
775 | * %rcx: thread info. Interrupts off. | |
776 | */ | |
777 | retint_with_reschedule: | |
778 | movl $_TIF_WORK_MASK,%edi | |
7effaa88 | 779 | retint_check: |
10cd706d | 780 | LOCKDEP_SYS_EXIT_IRQ |
26ccb8a7 | 781 | movl TI_flags(%rcx),%edx |
1da177e4 | 782 | andl %edi,%edx |
7effaa88 | 783 | CFI_REMEMBER_STATE |
1da177e4 | 784 | jnz retint_careful |
10cd706d PZ |
785 | |
786 | retint_swapgs: /* return to user-space */ | |
2601e64d IM |
787 | /* |
788 | * The iretq could re-enable interrupts: | |
789 | */ | |
72fe4858 | 790 | DISABLE_INTERRUPTS(CLBR_ANY) |
2601e64d | 791 | TRACE_IRQS_IRETQ |
72fe4858 | 792 | SWAPGS |
2601e64d IM |
793 | jmp restore_args |
794 | ||
10cd706d | 795 | retint_restore_args: /* return to kernel space */ |
72fe4858 | 796 | DISABLE_INTERRUPTS(CLBR_ANY) |
2601e64d IM |
797 | /* |
798 | * The iretq could re-enable interrupts: | |
799 | */ | |
800 | TRACE_IRQS_IRETQ | |
801 | restore_args: | |
3701d863 IM |
802 | RESTORE_ARGS 0,8,0 |
803 | ||
f7f3d791 | 804 | irq_return: |
72fe4858 | 805 | INTERRUPT_RETURN |
3701d863 IM |
806 | |
807 | .section __ex_table, "a" | |
808 | .quad irq_return, bad_iret | |
809 | .previous | |
810 | ||
811 | #ifdef CONFIG_PARAVIRT | |
72fe4858 | 812 | ENTRY(native_iret) |
1da177e4 LT |
813 | iretq |
814 | ||
815 | .section __ex_table,"a" | |
72fe4858 | 816 | .quad native_iret, bad_iret |
1da177e4 | 817 | .previous |
3701d863 IM |
818 | #endif |
819 | ||
1da177e4 | 820 | .section .fixup,"ax" |
1da177e4 | 821 | bad_iret: |
3aa4b37d RM |
822 | /* |
823 | * The iret traps when the %cs or %ss being restored is bogus. | |
824 | * We've lost the original trap vector and error code. | |
825 | * #GPF is the most likely one to get for an invalid selector. | |
826 | * So pretend we completed the iret and took the #GPF in user mode. | |
827 | * | |
828 | * We are now running with the kernel GS after exception recovery. | |
829 | * But error_entry expects us to have user GS to match the user %cs, | |
830 | * so swap back. | |
831 | */ | |
832 | pushq $0 | |
833 | ||
834 | SWAPGS | |
835 | jmp general_protection | |
836 | ||
72fe4858 GOC |
837 | .previous |
838 | ||
7effaa88 | 839 | /* edi: workmask, edx: work */ |
1da177e4 | 840 | retint_careful: |
7effaa88 | 841 | CFI_RESTORE_STATE |
1da177e4 LT |
842 | bt $TIF_NEED_RESCHED,%edx |
843 | jnc retint_signal | |
2601e64d | 844 | TRACE_IRQS_ON |
72fe4858 | 845 | ENABLE_INTERRUPTS(CLBR_NONE) |
1da177e4 | 846 | pushq %rdi |
7effaa88 | 847 | CFI_ADJUST_CFA_OFFSET 8 |
1da177e4 LT |
848 | call schedule |
849 | popq %rdi | |
7effaa88 | 850 | CFI_ADJUST_CFA_OFFSET -8 |
1da177e4 | 851 | GET_THREAD_INFO(%rcx) |
72fe4858 | 852 | DISABLE_INTERRUPTS(CLBR_NONE) |
2601e64d | 853 | TRACE_IRQS_OFF |
1da177e4 LT |
854 | jmp retint_check |
855 | ||
856 | retint_signal: | |
8f4d37ec | 857 | testl $_TIF_DO_NOTIFY_MASK,%edx |
10ffdbb8 | 858 | jz retint_swapgs |
2601e64d | 859 | TRACE_IRQS_ON |
72fe4858 | 860 | ENABLE_INTERRUPTS(CLBR_NONE) |
1da177e4 LT |
861 | SAVE_REST |
862 | movq $-1,ORIG_RAX(%rsp) | |
3829ee6b | 863 | xorl %esi,%esi # oldset |
1da177e4 LT |
864 | movq %rsp,%rdi # &pt_regs |
865 | call do_notify_resume | |
866 | RESTORE_REST | |
72fe4858 | 867 | DISABLE_INTERRUPTS(CLBR_NONE) |
2601e64d | 868 | TRACE_IRQS_OFF |
be9e6870 | 869 | GET_THREAD_INFO(%rcx) |
eca91e78 | 870 | jmp retint_with_reschedule |
1da177e4 LT |
871 | |
872 | #ifdef CONFIG_PREEMPT | |
873 | /* Returning to kernel space. Check if we need preemption */ | |
874 | /* rcx: threadinfo. interrupts off. */ | |
b06babac | 875 | ENTRY(retint_kernel) |
26ccb8a7 | 876 | cmpl $0,TI_preempt_count(%rcx) |
1da177e4 | 877 | jnz retint_restore_args |
26ccb8a7 | 878 | bt $TIF_NEED_RESCHED,TI_flags(%rcx) |
1da177e4 LT |
879 | jnc retint_restore_args |
880 | bt $9,EFLAGS-ARGOFFSET(%rsp) /* interrupts off? */ | |
881 | jnc retint_restore_args | |
882 | call preempt_schedule_irq | |
883 | jmp exit_intr | |
884 | #endif | |
4b787e0b | 885 | |
1da177e4 | 886 | CFI_ENDPROC |
4b787e0b | 887 | END(common_interrupt) |
1da177e4 LT |
888 | |
889 | /* | |
890 | * APIC interrupts. | |
891 | */ | |
892 | .macro apicinterrupt num,func | |
7effaa88 | 893 | INTR_FRAME |
19eadf98 | 894 | pushq $~(\num) |
7effaa88 | 895 | CFI_ADJUST_CFA_OFFSET 8 |
1da177e4 LT |
896 | interrupt \func |
897 | jmp ret_from_intr | |
898 | CFI_ENDPROC | |
899 | .endm | |
900 | ||
901 | ENTRY(thermal_interrupt) | |
902 | apicinterrupt THERMAL_APIC_VECTOR,smp_thermal_interrupt | |
4b787e0b | 903 | END(thermal_interrupt) |
1da177e4 | 904 | |
89b831ef JS |
905 | ENTRY(threshold_interrupt) |
906 | apicinterrupt THRESHOLD_APIC_VECTOR,mce_threshold_interrupt | |
4b787e0b | 907 | END(threshold_interrupt) |
89b831ef | 908 | |
1da177e4 LT |
909 | #ifdef CONFIG_SMP |
910 | ENTRY(reschedule_interrupt) | |
911 | apicinterrupt RESCHEDULE_VECTOR,smp_reschedule_interrupt | |
4b787e0b | 912 | END(reschedule_interrupt) |
1da177e4 | 913 | |
e5bc8b6b AK |
914 | .macro INVALIDATE_ENTRY num |
915 | ENTRY(invalidate_interrupt\num) | |
916 | apicinterrupt INVALIDATE_TLB_VECTOR_START+\num,smp_invalidate_interrupt | |
4b787e0b | 917 | END(invalidate_interrupt\num) |
e5bc8b6b AK |
918 | .endm |
919 | ||
920 | INVALIDATE_ENTRY 0 | |
921 | INVALIDATE_ENTRY 1 | |
922 | INVALIDATE_ENTRY 2 | |
923 | INVALIDATE_ENTRY 3 | |
924 | INVALIDATE_ENTRY 4 | |
925 | INVALIDATE_ENTRY 5 | |
926 | INVALIDATE_ENTRY 6 | |
927 | INVALIDATE_ENTRY 7 | |
1da177e4 LT |
928 | |
929 | ENTRY(call_function_interrupt) | |
930 | apicinterrupt CALL_FUNCTION_VECTOR,smp_call_function_interrupt | |
4b787e0b | 931 | END(call_function_interrupt) |
3b16cf87 JA |
932 | ENTRY(call_function_single_interrupt) |
933 | apicinterrupt CALL_FUNCTION_SINGLE_VECTOR,smp_call_function_single_interrupt | |
934 | END(call_function_single_interrupt) | |
61014292 EB |
935 | ENTRY(irq_move_cleanup_interrupt) |
936 | apicinterrupt IRQ_MOVE_CLEANUP_VECTOR,smp_irq_move_cleanup_interrupt | |
937 | END(irq_move_cleanup_interrupt) | |
1da177e4 LT |
938 | #endif |
939 | ||
1da177e4 LT |
940 | ENTRY(apic_timer_interrupt) |
941 | apicinterrupt LOCAL_TIMER_VECTOR,smp_apic_timer_interrupt | |
4b787e0b | 942 | END(apic_timer_interrupt) |
1da177e4 | 943 | |
1812924b CW |
944 | ENTRY(uv_bau_message_intr1) |
945 | apicinterrupt 220,uv_bau_message_interrupt | |
946 | END(uv_bau_message_intr1) | |
947 | ||
1da177e4 LT |
948 | ENTRY(error_interrupt) |
949 | apicinterrupt ERROR_APIC_VECTOR,smp_error_interrupt | |
4b787e0b | 950 | END(error_interrupt) |
1da177e4 LT |
951 | |
952 | ENTRY(spurious_interrupt) | |
953 | apicinterrupt SPURIOUS_APIC_VECTOR,smp_spurious_interrupt | |
4b787e0b | 954 | END(spurious_interrupt) |
1da177e4 LT |
955 | |
956 | /* | |
957 | * Exception entry points. | |
958 | */ | |
959 | .macro zeroentry sym | |
7effaa88 | 960 | INTR_FRAME |
fab58420 | 961 | PARAVIRT_ADJUST_EXCEPTION_FRAME |
1da177e4 | 962 | pushq $0 /* push error code/oldrax */ |
7effaa88 | 963 | CFI_ADJUST_CFA_OFFSET 8 |
1da177e4 | 964 | pushq %rax /* push real oldrax to the rdi slot */ |
7effaa88 | 965 | CFI_ADJUST_CFA_OFFSET 8 |
37550907 | 966 | CFI_REL_OFFSET rax,0 |
1da177e4 LT |
967 | leaq \sym(%rip),%rax |
968 | jmp error_entry | |
7effaa88 | 969 | CFI_ENDPROC |
1da177e4 LT |
970 | .endm |
971 | ||
972 | .macro errorentry sym | |
7effaa88 | 973 | XCPT_FRAME |
fab58420 | 974 | PARAVIRT_ADJUST_EXCEPTION_FRAME |
1da177e4 | 975 | pushq %rax |
7effaa88 | 976 | CFI_ADJUST_CFA_OFFSET 8 |
37550907 | 977 | CFI_REL_OFFSET rax,0 |
1da177e4 LT |
978 | leaq \sym(%rip),%rax |
979 | jmp error_entry | |
7effaa88 | 980 | CFI_ENDPROC |
1da177e4 LT |
981 | .endm |
982 | ||
983 | /* error code is on the stack already */ | |
984 | /* handle NMI like exceptions that can happen everywhere */ | |
2601e64d | 985 | .macro paranoidentry sym, ist=0, irqtrace=1 |
1da177e4 LT |
986 | SAVE_ALL |
987 | cld | |
988 | movl $1,%ebx | |
989 | movl $MSR_GS_BASE,%ecx | |
990 | rdmsr | |
991 | testl %edx,%edx | |
992 | js 1f | |
72fe4858 | 993 | SWAPGS |
1da177e4 | 994 | xorl %ebx,%ebx |
b556b35e JB |
995 | 1: |
996 | .if \ist | |
997 | movq %gs:pda_data_offset, %rbp | |
998 | .endif | |
7e61a793 AH |
999 | .if \irqtrace |
1000 | TRACE_IRQS_OFF | |
1001 | .endif | |
b556b35e | 1002 | movq %rsp,%rdi |
1da177e4 LT |
1003 | movq ORIG_RAX(%rsp),%rsi |
1004 | movq $-1,ORIG_RAX(%rsp) | |
b556b35e | 1005 | .if \ist |
5f8efbb9 | 1006 | subq $EXCEPTION_STKSZ, per_cpu__init_tss + TSS_ist + (\ist - 1) * 8(%rbp) |
b556b35e | 1007 | .endif |
1da177e4 | 1008 | call \sym |
b556b35e | 1009 | .if \ist |
5f8efbb9 | 1010 | addq $EXCEPTION_STKSZ, per_cpu__init_tss + TSS_ist + (\ist - 1) * 8(%rbp) |
b556b35e | 1011 | .endif |
72fe4858 | 1012 | DISABLE_INTERRUPTS(CLBR_NONE) |
2601e64d IM |
1013 | .if \irqtrace |
1014 | TRACE_IRQS_OFF | |
1015 | .endif | |
1da177e4 | 1016 | .endm |
2601e64d IM |
1017 | |
1018 | /* | |
1019 | * "Paranoid" exit path from exception stack. | |
1020 | * Paranoid because this is used by NMIs and cannot take | |
1021 | * any kernel state for granted. | |
1022 | * We don't do kernel preemption checks here, because only | |
1023 | * NMI should be common and it does not enable IRQs and | |
1024 | * cannot get reschedule ticks. | |
1025 | * | |
1026 | * "trace" is 0 for the NMI handler only, because irq-tracing | |
1027 | * is fundamentally NMI-unsafe. (we cannot change the soft and | |
1028 | * hard flags at once, atomically) | |
1029 | */ | |
1030 | .macro paranoidexit trace=1 | |
1031 | /* ebx: no swapgs flag */ | |
1032 | paranoid_exit\trace: | |
1033 | testl %ebx,%ebx /* swapgs needed? */ | |
1034 | jnz paranoid_restore\trace | |
1035 | testl $3,CS(%rsp) | |
1036 | jnz paranoid_userspace\trace | |
1037 | paranoid_swapgs\trace: | |
7a0a2dff | 1038 | .if \trace |
2601e64d | 1039 | TRACE_IRQS_IRETQ 0 |
7a0a2dff | 1040 | .endif |
72fe4858 | 1041 | SWAPGS_UNSAFE_STACK |
2601e64d IM |
1042 | paranoid_restore\trace: |
1043 | RESTORE_ALL 8 | |
3701d863 | 1044 | jmp irq_return |
2601e64d IM |
1045 | paranoid_userspace\trace: |
1046 | GET_THREAD_INFO(%rcx) | |
26ccb8a7 | 1047 | movl TI_flags(%rcx),%ebx |
2601e64d IM |
1048 | andl $_TIF_WORK_MASK,%ebx |
1049 | jz paranoid_swapgs\trace | |
1050 | movq %rsp,%rdi /* &pt_regs */ | |
1051 | call sync_regs | |
1052 | movq %rax,%rsp /* switch stack for scheduling */ | |
1053 | testl $_TIF_NEED_RESCHED,%ebx | |
1054 | jnz paranoid_schedule\trace | |
1055 | movl %ebx,%edx /* arg3: thread flags */ | |
1056 | .if \trace | |
1057 | TRACE_IRQS_ON | |
1058 | .endif | |
72fe4858 | 1059 | ENABLE_INTERRUPTS(CLBR_NONE) |
2601e64d IM |
1060 | xorl %esi,%esi /* arg2: oldset */ |
1061 | movq %rsp,%rdi /* arg1: &pt_regs */ | |
1062 | call do_notify_resume | |
72fe4858 | 1063 | DISABLE_INTERRUPTS(CLBR_NONE) |
2601e64d IM |
1064 | .if \trace |
1065 | TRACE_IRQS_OFF | |
1066 | .endif | |
1067 | jmp paranoid_userspace\trace | |
1068 | paranoid_schedule\trace: | |
1069 | .if \trace | |
1070 | TRACE_IRQS_ON | |
1071 | .endif | |
72fe4858 | 1072 | ENABLE_INTERRUPTS(CLBR_ANY) |
2601e64d | 1073 | call schedule |
72fe4858 | 1074 | DISABLE_INTERRUPTS(CLBR_ANY) |
2601e64d IM |
1075 | .if \trace |
1076 | TRACE_IRQS_OFF | |
1077 | .endif | |
1078 | jmp paranoid_userspace\trace | |
1079 | CFI_ENDPROC | |
1080 | .endm | |
1081 | ||
1da177e4 LT |
1082 | /* |
1083 | * Exception entry point. This expects an error code/orig_rax on the stack | |
1084 | * and the exception handler in %rax. | |
1085 | */ | |
d28c4393 | 1086 | KPROBE_ENTRY(error_entry) |
7effaa88 | 1087 | _frame RDI |
37550907 | 1088 | CFI_REL_OFFSET rax,0 |
1da177e4 LT |
1089 | /* rdi slot contains rax, oldrax contains error code */ |
1090 | cld | |
1091 | subq $14*8,%rsp | |
1092 | CFI_ADJUST_CFA_OFFSET (14*8) | |
1093 | movq %rsi,13*8(%rsp) | |
1094 | CFI_REL_OFFSET rsi,RSI | |
1095 | movq 14*8(%rsp),%rsi /* load rax from rdi slot */ | |
37550907 | 1096 | CFI_REGISTER rax,rsi |
1da177e4 LT |
1097 | movq %rdx,12*8(%rsp) |
1098 | CFI_REL_OFFSET rdx,RDX | |
1099 | movq %rcx,11*8(%rsp) | |
1100 | CFI_REL_OFFSET rcx,RCX | |
1101 | movq %rsi,10*8(%rsp) /* store rax */ | |
1102 | CFI_REL_OFFSET rax,RAX | |
1103 | movq %r8, 9*8(%rsp) | |
1104 | CFI_REL_OFFSET r8,R8 | |
1105 | movq %r9, 8*8(%rsp) | |
1106 | CFI_REL_OFFSET r9,R9 | |
1107 | movq %r10,7*8(%rsp) | |
1108 | CFI_REL_OFFSET r10,R10 | |
1109 | movq %r11,6*8(%rsp) | |
1110 | CFI_REL_OFFSET r11,R11 | |
1111 | movq %rbx,5*8(%rsp) | |
1112 | CFI_REL_OFFSET rbx,RBX | |
1113 | movq %rbp,4*8(%rsp) | |
1114 | CFI_REL_OFFSET rbp,RBP | |
1115 | movq %r12,3*8(%rsp) | |
1116 | CFI_REL_OFFSET r12,R12 | |
1117 | movq %r13,2*8(%rsp) | |
1118 | CFI_REL_OFFSET r13,R13 | |
1119 | movq %r14,1*8(%rsp) | |
1120 | CFI_REL_OFFSET r14,R14 | |
1121 | movq %r15,(%rsp) | |
1122 | CFI_REL_OFFSET r15,R15 | |
1123 | xorl %ebx,%ebx | |
1124 | testl $3,CS(%rsp) | |
1125 | je error_kernelspace | |
1126 | error_swapgs: | |
72fe4858 | 1127 | SWAPGS |
6b11d4ef AH |
1128 | error_sti: |
1129 | TRACE_IRQS_OFF | |
1da177e4 | 1130 | movq %rdi,RDI(%rsp) |
37550907 | 1131 | CFI_REL_OFFSET rdi,RDI |
1da177e4 LT |
1132 | movq %rsp,%rdi |
1133 | movq ORIG_RAX(%rsp),%rsi /* get error code */ | |
1134 | movq $-1,ORIG_RAX(%rsp) | |
1135 | call *%rax | |
10cd706d PZ |
1136 | /* ebx: no swapgs flag (1: don't need swapgs, 0: need it) */ |
1137 | error_exit: | |
1138 | movl %ebx,%eax | |
1da177e4 | 1139 | RESTORE_REST |
72fe4858 | 1140 | DISABLE_INTERRUPTS(CLBR_NONE) |
2601e64d | 1141 | TRACE_IRQS_OFF |
1da177e4 LT |
1142 | GET_THREAD_INFO(%rcx) |
1143 | testl %eax,%eax | |
1144 | jne retint_kernel | |
10cd706d | 1145 | LOCKDEP_SYS_EXIT_IRQ |
26ccb8a7 | 1146 | movl TI_flags(%rcx),%edx |
1da177e4 LT |
1147 | movl $_TIF_WORK_MASK,%edi |
1148 | andl %edi,%edx | |
1149 | jnz retint_careful | |
10cd706d | 1150 | jmp retint_swapgs |
1da177e4 LT |
1151 | CFI_ENDPROC |
1152 | ||
1153 | error_kernelspace: | |
1154 | incl %ebx | |
1155 | /* There are two places in the kernel that can potentially fault with | |
1156 | usergs. Handle them here. The exception handlers after | |
1157 | iret run with kernel gs again, so don't set the user space flag. | |
1158 | B stepping K8s sometimes report an truncated RIP for IRET | |
1159 | exceptions returning to compat mode. Check for these here too. */ | |
9d8ad5d6 VN |
1160 | leaq irq_return(%rip),%rcx |
1161 | cmpq %rcx,RIP(%rsp) | |
1da177e4 | 1162 | je error_swapgs |
9d8ad5d6 VN |
1163 | movl %ecx,%ecx /* zero extend */ |
1164 | cmpq %rcx,RIP(%rsp) | |
1da177e4 LT |
1165 | je error_swapgs |
1166 | cmpq $gs_change,RIP(%rsp) | |
1167 | je error_swapgs | |
1168 | jmp error_sti | |
d28c4393 | 1169 | KPROBE_END(error_entry) |
1da177e4 LT |
1170 | |
1171 | /* Reload gs selector with exception handling */ | |
1172 | /* edi: new selector */ | |
9f9d489a | 1173 | ENTRY(native_load_gs_index) |
7effaa88 | 1174 | CFI_STARTPROC |
1da177e4 | 1175 | pushf |
7effaa88 | 1176 | CFI_ADJUST_CFA_OFFSET 8 |
72fe4858 GOC |
1177 | DISABLE_INTERRUPTS(CLBR_ANY | ~(CLBR_RDI)) |
1178 | SWAPGS | |
1da177e4 LT |
1179 | gs_change: |
1180 | movl %edi,%gs | |
1181 | 2: mfence /* workaround */ | |
72fe4858 | 1182 | SWAPGS |
1da177e4 | 1183 | popf |
7effaa88 | 1184 | CFI_ADJUST_CFA_OFFSET -8 |
1da177e4 | 1185 | ret |
7effaa88 | 1186 | CFI_ENDPROC |
9f9d489a | 1187 | ENDPROC(native_load_gs_index) |
1da177e4 LT |
1188 | |
1189 | .section __ex_table,"a" | |
1190 | .align 8 | |
1191 | .quad gs_change,bad_gs | |
1192 | .previous | |
1193 | .section .fixup,"ax" | |
1194 | /* running with kernelgs */ | |
1195 | bad_gs: | |
72fe4858 | 1196 | SWAPGS /* switch back to user gs */ |
1da177e4 LT |
1197 | xorl %eax,%eax |
1198 | movl %eax,%gs | |
1199 | jmp 2b | |
1200 | .previous | |
1201 | ||
1202 | /* | |
1203 | * Create a kernel thread. | |
1204 | * | |
1205 | * C extern interface: | |
1206 | * extern long kernel_thread(int (*fn)(void *), void * arg, unsigned long flags) | |
1207 | * | |
1208 | * asm input arguments: | |
1209 | * rdi: fn, rsi: arg, rdx: flags | |
1210 | */ | |
1211 | ENTRY(kernel_thread) | |
1212 | CFI_STARTPROC | |
1213 | FAKE_STACK_FRAME $child_rip | |
1214 | SAVE_ALL | |
1215 | ||
1216 | # rdi: flags, rsi: usp, rdx: will be &pt_regs | |
1217 | movq %rdx,%rdi | |
1218 | orq kernel_thread_flags(%rip),%rdi | |
1219 | movq $-1, %rsi | |
1220 | movq %rsp, %rdx | |
1221 | ||
1222 | xorl %r8d,%r8d | |
1223 | xorl %r9d,%r9d | |
1224 | ||
1225 | # clone now | |
1226 | call do_fork | |
1227 | movq %rax,RAX(%rsp) | |
1228 | xorl %edi,%edi | |
1229 | ||
1230 | /* | |
1231 | * It isn't worth to check for reschedule here, | |
1232 | * so internally to the x86_64 port you can rely on kernel_thread() | |
1233 | * not to reschedule the child before returning, this avoids the need | |
1234 | * of hacks for example to fork off the per-CPU idle tasks. | |
1235 | * [Hopefully no generic code relies on the reschedule -AK] | |
1236 | */ | |
1237 | RESTORE_ALL | |
1238 | UNFAKE_STACK_FRAME | |
1239 | ret | |
1240 | CFI_ENDPROC | |
4b787e0b | 1241 | ENDPROC(kernel_thread) |
1da177e4 LT |
1242 | |
1243 | child_rip: | |
c05991ed AK |
1244 | pushq $0 # fake return address |
1245 | CFI_STARTPROC | |
1da177e4 LT |
1246 | /* |
1247 | * Here we are in the child and the registers are set as they were | |
1248 | * at kernel_thread() invocation in the parent. | |
1249 | */ | |
1250 | movq %rdi, %rax | |
1251 | movq %rsi, %rdi | |
1252 | call *%rax | |
1253 | # exit | |
1c5b5cfd | 1254 | mov %eax, %edi |
1da177e4 | 1255 | call do_exit |
c05991ed | 1256 | CFI_ENDPROC |
4b787e0b | 1257 | ENDPROC(child_rip) |
1da177e4 LT |
1258 | |
1259 | /* | |
1260 | * execve(). This function needs to use IRET, not SYSRET, to set up all state properly. | |
1261 | * | |
1262 | * C extern interface: | |
1263 | * extern long execve(char *name, char **argv, char **envp) | |
1264 | * | |
1265 | * asm input arguments: | |
1266 | * rdi: name, rsi: argv, rdx: envp | |
1267 | * | |
1268 | * We want to fallback into: | |
5d119b2c | 1269 | * extern long sys_execve(char *name, char **argv,char **envp, struct pt_regs *regs) |
1da177e4 LT |
1270 | * |
1271 | * do_sys_execve asm fallback arguments: | |
5d119b2c | 1272 | * rdi: name, rsi: argv, rdx: envp, rcx: fake frame on the stack |
1da177e4 | 1273 | */ |
3db03b4a | 1274 | ENTRY(kernel_execve) |
1da177e4 LT |
1275 | CFI_STARTPROC |
1276 | FAKE_STACK_FRAME $0 | |
1277 | SAVE_ALL | |
5d119b2c | 1278 | movq %rsp,%rcx |
1da177e4 LT |
1279 | call sys_execve |
1280 | movq %rax, RAX(%rsp) | |
1281 | RESTORE_REST | |
1282 | testq %rax,%rax | |
1283 | je int_ret_from_sys_call | |
1284 | RESTORE_ARGS | |
1285 | UNFAKE_STACK_FRAME | |
1286 | ret | |
1287 | CFI_ENDPROC | |
3db03b4a | 1288 | ENDPROC(kernel_execve) |
1da177e4 | 1289 | |
0f2fbdcb | 1290 | KPROBE_ENTRY(page_fault) |
1da177e4 | 1291 | errorentry do_page_fault |
d28c4393 | 1292 | KPROBE_END(page_fault) |
1da177e4 LT |
1293 | |
1294 | ENTRY(coprocessor_error) | |
1295 | zeroentry do_coprocessor_error | |
4b787e0b | 1296 | END(coprocessor_error) |
1da177e4 LT |
1297 | |
1298 | ENTRY(simd_coprocessor_error) | |
1299 | zeroentry do_simd_coprocessor_error | |
4b787e0b | 1300 | END(simd_coprocessor_error) |
1da177e4 LT |
1301 | |
1302 | ENTRY(device_not_available) | |
e407d620 | 1303 | zeroentry do_device_not_available |
4b787e0b | 1304 | END(device_not_available) |
1da177e4 LT |
1305 | |
1306 | /* runs on exception stack */ | |
0f2fbdcb | 1307 | KPROBE_ENTRY(debug) |
7effaa88 | 1308 | INTR_FRAME |
09402947 | 1309 | PARAVIRT_ADJUST_EXCEPTION_FRAME |
1da177e4 LT |
1310 | pushq $0 |
1311 | CFI_ADJUST_CFA_OFFSET 8 | |
5f8efbb9 | 1312 | paranoidentry do_debug, DEBUG_STACK |
2601e64d | 1313 | paranoidexit |
d28c4393 | 1314 | KPROBE_END(debug) |
1da177e4 LT |
1315 | |
1316 | /* runs on exception stack */ | |
eddb6fb9 | 1317 | KPROBE_ENTRY(nmi) |
7effaa88 | 1318 | INTR_FRAME |
09402947 | 1319 | PARAVIRT_ADJUST_EXCEPTION_FRAME |
1da177e4 | 1320 | pushq $-1 |
7effaa88 | 1321 | CFI_ADJUST_CFA_OFFSET 8 |
2601e64d IM |
1322 | paranoidentry do_nmi, 0, 0 |
1323 | #ifdef CONFIG_TRACE_IRQFLAGS | |
1324 | paranoidexit 0 | |
1325 | #else | |
1326 | jmp paranoid_exit1 | |
1327 | CFI_ENDPROC | |
1328 | #endif | |
d28c4393 | 1329 | KPROBE_END(nmi) |
6fefb0d1 | 1330 | |
0f2fbdcb | 1331 | KPROBE_ENTRY(int3) |
b556b35e | 1332 | INTR_FRAME |
09402947 | 1333 | PARAVIRT_ADJUST_EXCEPTION_FRAME |
b556b35e JB |
1334 | pushq $0 |
1335 | CFI_ADJUST_CFA_OFFSET 8 | |
5f8efbb9 | 1336 | paranoidentry do_int3, DEBUG_STACK |
2601e64d | 1337 | jmp paranoid_exit1 |
b556b35e | 1338 | CFI_ENDPROC |
d28c4393 | 1339 | KPROBE_END(int3) |
1da177e4 LT |
1340 | |
1341 | ENTRY(overflow) | |
1342 | zeroentry do_overflow | |
4b787e0b | 1343 | END(overflow) |
1da177e4 LT |
1344 | |
1345 | ENTRY(bounds) | |
1346 | zeroentry do_bounds | |
4b787e0b | 1347 | END(bounds) |
1da177e4 LT |
1348 | |
1349 | ENTRY(invalid_op) | |
1350 | zeroentry do_invalid_op | |
4b787e0b | 1351 | END(invalid_op) |
1da177e4 LT |
1352 | |
1353 | ENTRY(coprocessor_segment_overrun) | |
1354 | zeroentry do_coprocessor_segment_overrun | |
4b787e0b | 1355 | END(coprocessor_segment_overrun) |
1da177e4 | 1356 | |
1da177e4 LT |
1357 | /* runs on exception stack */ |
1358 | ENTRY(double_fault) | |
7effaa88 | 1359 | XCPT_FRAME |
09402947 | 1360 | PARAVIRT_ADJUST_EXCEPTION_FRAME |
1da177e4 | 1361 | paranoidentry do_double_fault |
2601e64d | 1362 | jmp paranoid_exit1 |
1da177e4 | 1363 | CFI_ENDPROC |
4b787e0b | 1364 | END(double_fault) |
1da177e4 LT |
1365 | |
1366 | ENTRY(invalid_TSS) | |
1367 | errorentry do_invalid_TSS | |
4b787e0b | 1368 | END(invalid_TSS) |
1da177e4 LT |
1369 | |
1370 | ENTRY(segment_not_present) | |
1371 | errorentry do_segment_not_present | |
4b787e0b | 1372 | END(segment_not_present) |
1da177e4 LT |
1373 | |
1374 | /* runs on exception stack */ | |
1375 | ENTRY(stack_segment) | |
7effaa88 | 1376 | XCPT_FRAME |
09402947 | 1377 | PARAVIRT_ADJUST_EXCEPTION_FRAME |
1da177e4 | 1378 | paranoidentry do_stack_segment |
2601e64d | 1379 | jmp paranoid_exit1 |
1da177e4 | 1380 | CFI_ENDPROC |
4b787e0b | 1381 | END(stack_segment) |
1da177e4 | 1382 | |
0f2fbdcb | 1383 | KPROBE_ENTRY(general_protection) |
1da177e4 | 1384 | errorentry do_general_protection |
d28c4393 | 1385 | KPROBE_END(general_protection) |
1da177e4 LT |
1386 | |
1387 | ENTRY(alignment_check) | |
1388 | errorentry do_alignment_check | |
4b787e0b | 1389 | END(alignment_check) |
1da177e4 LT |
1390 | |
1391 | ENTRY(divide_error) | |
1392 | zeroentry do_divide_error | |
4b787e0b | 1393 | END(divide_error) |
1da177e4 LT |
1394 | |
1395 | ENTRY(spurious_interrupt_bug) | |
1396 | zeroentry do_spurious_interrupt_bug | |
4b787e0b | 1397 | END(spurious_interrupt_bug) |
1da177e4 LT |
1398 | |
1399 | #ifdef CONFIG_X86_MCE | |
1400 | /* runs on exception stack */ | |
1401 | ENTRY(machine_check) | |
7effaa88 | 1402 | INTR_FRAME |
09402947 | 1403 | PARAVIRT_ADJUST_EXCEPTION_FRAME |
1da177e4 LT |
1404 | pushq $0 |
1405 | CFI_ADJUST_CFA_OFFSET 8 | |
1406 | paranoidentry do_machine_check | |
2601e64d | 1407 | jmp paranoid_exit1 |
1da177e4 | 1408 | CFI_ENDPROC |
4b787e0b | 1409 | END(machine_check) |
1da177e4 LT |
1410 | #endif |
1411 | ||
2699500b | 1412 | /* Call softirq on interrupt stack. Interrupts are off. */ |
ed6b676c | 1413 | ENTRY(call_softirq) |
7effaa88 | 1414 | CFI_STARTPROC |
2699500b AK |
1415 | push %rbp |
1416 | CFI_ADJUST_CFA_OFFSET 8 | |
1417 | CFI_REL_OFFSET rbp,0 | |
1418 | mov %rsp,%rbp | |
1419 | CFI_DEF_CFA_REGISTER rbp | |
ed6b676c | 1420 | incl %gs:pda_irqcount |
2699500b AK |
1421 | cmove %gs:pda_irqstackptr,%rsp |
1422 | push %rbp # backlink for old unwinder | |
ed6b676c | 1423 | call __do_softirq |
2699500b | 1424 | leaveq |
7effaa88 | 1425 | CFI_DEF_CFA_REGISTER rsp |
2699500b | 1426 | CFI_ADJUST_CFA_OFFSET -8 |
ed6b676c | 1427 | decl %gs:pda_irqcount |
ed6b676c | 1428 | ret |
7effaa88 | 1429 | CFI_ENDPROC |
4b787e0b | 1430 | ENDPROC(call_softirq) |
75154f40 AK |
1431 | |
1432 | KPROBE_ENTRY(ignore_sysret) | |
1433 | CFI_STARTPROC | |
1434 | mov $-ENOSYS,%eax | |
1435 | sysret | |
1436 | CFI_ENDPROC | |
1437 | ENDPROC(ignore_sysret) | |
3d75e1b8 JF |
1438 | |
1439 | #ifdef CONFIG_XEN | |
1440 | ENTRY(xen_hypervisor_callback) | |
1441 | zeroentry xen_do_hypervisor_callback | |
1442 | END(xen_hypervisor_callback) | |
1443 | ||
1444 | /* | |
1445 | # A note on the "critical region" in our callback handler. | |
1446 | # We want to avoid stacking callback handlers due to events occurring | |
1447 | # during handling of the last event. To do this, we keep events disabled | |
1448 | # until we've done all processing. HOWEVER, we must enable events before | |
1449 | # popping the stack frame (can't be done atomically) and so it would still | |
1450 | # be possible to get enough handler activations to overflow the stack. | |
1451 | # Although unlikely, bugs of that kind are hard to track down, so we'd | |
1452 | # like to avoid the possibility. | |
1453 | # So, on entry to the handler we detect whether we interrupted an | |
1454 | # existing activation in its critical region -- if so, we pop the current | |
1455 | # activation and restart the handler using the previous one. | |
1456 | */ | |
1457 | ENTRY(xen_do_hypervisor_callback) # do_hypervisor_callback(struct *pt_regs) | |
1458 | CFI_STARTPROC | |
1459 | /* Since we don't modify %rdi, evtchn_do_upall(struct *pt_regs) will | |
1460 | see the correct pointer to the pt_regs */ | |
1461 | movq %rdi, %rsp # we don't return, adjust the stack frame | |
1462 | CFI_ENDPROC | |
1463 | CFI_DEFAULT_STACK | |
1464 | 11: incl %gs:pda_irqcount | |
1465 | movq %rsp,%rbp | |
1466 | CFI_DEF_CFA_REGISTER rbp | |
1467 | cmovzq %gs:pda_irqstackptr,%rsp | |
1468 | pushq %rbp # backlink for old unwinder | |
1469 | call xen_evtchn_do_upcall | |
1470 | popq %rsp | |
1471 | CFI_DEF_CFA_REGISTER rsp | |
1472 | decl %gs:pda_irqcount | |
1473 | jmp error_exit | |
1474 | CFI_ENDPROC | |
1475 | END(do_hypervisor_callback) | |
1476 | ||
1477 | /* | |
1478 | # Hypervisor uses this for application faults while it executes. | |
1479 | # We get here for two reasons: | |
1480 | # 1. Fault while reloading DS, ES, FS or GS | |
1481 | # 2. Fault while executing IRET | |
1482 | # Category 1 we do not need to fix up as Xen has already reloaded all segment | |
1483 | # registers that could be reloaded and zeroed the others. | |
1484 | # Category 2 we fix up by killing the current process. We cannot use the | |
1485 | # normal Linux return path in this case because if we use the IRET hypercall | |
1486 | # to pop the stack frame we end up in an infinite loop of failsafe callbacks. | |
1487 | # We distinguish between categories by comparing each saved segment register | |
1488 | # with its current contents: any discrepancy means we in category 1. | |
1489 | */ | |
1490 | ENTRY(xen_failsafe_callback) | |
4a5c3e77 JF |
1491 | framesz = (RIP-0x30) /* workaround buggy gas */ |
1492 | _frame framesz | |
3d75e1b8 JF |
1493 | CFI_REL_OFFSET rcx, 0 |
1494 | CFI_REL_OFFSET r11, 8 | |
1495 | movw %ds,%cx | |
1496 | cmpw %cx,0x10(%rsp) | |
1497 | CFI_REMEMBER_STATE | |
1498 | jne 1f | |
1499 | movw %es,%cx | |
1500 | cmpw %cx,0x18(%rsp) | |
1501 | jne 1f | |
1502 | movw %fs,%cx | |
1503 | cmpw %cx,0x20(%rsp) | |
1504 | jne 1f | |
1505 | movw %gs,%cx | |
1506 | cmpw %cx,0x28(%rsp) | |
1507 | jne 1f | |
1508 | /* All segments match their saved values => Category 2 (Bad IRET). */ | |
1509 | movq (%rsp),%rcx | |
1510 | CFI_RESTORE rcx | |
1511 | movq 8(%rsp),%r11 | |
1512 | CFI_RESTORE r11 | |
1513 | addq $0x30,%rsp | |
1514 | CFI_ADJUST_CFA_OFFSET -0x30 | |
4a5c3e77 JF |
1515 | pushq $0 |
1516 | CFI_ADJUST_CFA_OFFSET 8 | |
1517 | pushq %r11 | |
1518 | CFI_ADJUST_CFA_OFFSET 8 | |
1519 | pushq %rcx | |
1520 | CFI_ADJUST_CFA_OFFSET 8 | |
1521 | jmp general_protection | |
3d75e1b8 JF |
1522 | CFI_RESTORE_STATE |
1523 | 1: /* Segment mismatch => Category 1 (Bad segment). Retry the IRET. */ | |
1524 | movq (%rsp),%rcx | |
1525 | CFI_RESTORE rcx | |
1526 | movq 8(%rsp),%r11 | |
1527 | CFI_RESTORE r11 | |
1528 | addq $0x30,%rsp | |
1529 | CFI_ADJUST_CFA_OFFSET -0x30 | |
1530 | pushq $0 | |
1531 | CFI_ADJUST_CFA_OFFSET 8 | |
1532 | SAVE_ALL | |
1533 | jmp error_exit | |
1534 | CFI_ENDPROC | |
3d75e1b8 JF |
1535 | END(xen_failsafe_callback) |
1536 | ||
1537 | #endif /* CONFIG_XEN */ |