Commit | Line | Data |
---|---|---|
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. | |
0bd7b798 AH |
14 | * |
15 | * Normal syscalls and interrupts don't save a full stack frame, this is | |
1da177e4 | 16 | * only done for syscall tracing, signals or fork/exec et.al. |
0bd7b798 AH |
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. | |
1da177e4 | 21 | * - partial stack frame: partially saved registers upto R11. |
0bd7b798 | 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> | |
0341c14d | 51 | #include <asm/page_types.h> |
2601e64d | 52 | #include <asm/irqflags.h> |
72fe4858 | 53 | #include <asm/paravirt.h> |
395a59d0 | 54 | #include <asm/ftrace.h> |
9939ddaf | 55 | #include <asm/percpu.h> |
1da177e4 | 56 | |
86a1c34a RM |
57 | /* Avoid __ASSEMBLER__'ifying <linux/audit.h> just for this. */ |
58 | #include <linux/elf-em.h> | |
59 | #define AUDIT_ARCH_X86_64 (EM_X86_64|__AUDIT_ARCH_64BIT|__AUDIT_ARCH_LE) | |
60 | #define __AUDIT_ARCH_64BIT 0x80000000 | |
61 | #define __AUDIT_ARCH_LE 0x40000000 | |
62 | ||
1da177e4 | 63 | .code64 |
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 | 73 | |
d680fe44 | 74 | MCOUNT_SAVE_FRAME |
d61f82d0 SR |
75 | |
76 | movq 0x38(%rsp), %rdi | |
77 | movq 8(%rbp), %rsi | |
395a59d0 | 78 | subq $MCOUNT_INSN_SIZE, %rdi |
d61f82d0 | 79 | |
bc8b2b92 | 80 | GLOBAL(ftrace_call) |
d61f82d0 SR |
81 | call ftrace_stub |
82 | ||
d680fe44 | 83 | MCOUNT_RESTORE_FRAME |
d61f82d0 | 84 | |
48d68b20 | 85 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
bc8b2b92 | 86 | GLOBAL(ftrace_graph_call) |
48d68b20 FW |
87 | jmp ftrace_stub |
88 | #endif | |
d61f82d0 | 89 | |
bc8b2b92 | 90 | GLOBAL(ftrace_stub) |
d61f82d0 SR |
91 | retq |
92 | END(ftrace_caller) | |
93 | ||
94 | #else /* ! CONFIG_DYNAMIC_FTRACE */ | |
16444a8a | 95 | ENTRY(mcount) |
60a7ecf4 SR |
96 | cmpl $0, function_trace_stop |
97 | jne ftrace_stub | |
98 | ||
16444a8a ACM |
99 | cmpq $ftrace_stub, ftrace_trace_function |
100 | jnz trace | |
48d68b20 FW |
101 | |
102 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER | |
103 | cmpq $ftrace_stub, ftrace_graph_return | |
104 | jnz ftrace_graph_caller | |
e49dc19c SR |
105 | |
106 | cmpq $ftrace_graph_entry_stub, ftrace_graph_entry | |
107 | jnz ftrace_graph_caller | |
48d68b20 FW |
108 | #endif |
109 | ||
bc8b2b92 | 110 | GLOBAL(ftrace_stub) |
16444a8a ACM |
111 | retq |
112 | ||
113 | trace: | |
d680fe44 | 114 | MCOUNT_SAVE_FRAME |
16444a8a ACM |
115 | |
116 | movq 0x38(%rsp), %rdi | |
117 | movq 8(%rbp), %rsi | |
395a59d0 | 118 | subq $MCOUNT_INSN_SIZE, %rdi |
16444a8a ACM |
119 | |
120 | call *ftrace_trace_function | |
121 | ||
d680fe44 | 122 | MCOUNT_RESTORE_FRAME |
16444a8a ACM |
123 | |
124 | jmp ftrace_stub | |
125 | END(mcount) | |
d61f82d0 | 126 | #endif /* CONFIG_DYNAMIC_FTRACE */ |
606576ce | 127 | #endif /* CONFIG_FUNCTION_TRACER */ |
16444a8a | 128 | |
48d68b20 FW |
129 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
130 | ENTRY(ftrace_graph_caller) | |
131 | cmpl $0, function_trace_stop | |
132 | jne ftrace_stub | |
133 | ||
d680fe44 | 134 | MCOUNT_SAVE_FRAME |
48d68b20 FW |
135 | |
136 | leaq 8(%rbp), %rdi | |
137 | movq 0x38(%rsp), %rsi | |
71e308a2 | 138 | movq (%rbp), %rdx |
bb4304c7 | 139 | subq $MCOUNT_INSN_SIZE, %rsi |
48d68b20 FW |
140 | |
141 | call prepare_ftrace_return | |
142 | ||
d680fe44 CG |
143 | MCOUNT_RESTORE_FRAME |
144 | ||
48d68b20 FW |
145 | retq |
146 | END(ftrace_graph_caller) | |
147 | ||
bc8b2b92 | 148 | GLOBAL(return_to_handler) |
4818d809 | 149 | subq $24, %rsp |
48d68b20 | 150 | |
e71e99c2 | 151 | /* Save the return values */ |
16444a8a | 152 | movq %rax, (%rsp) |
e71e99c2 | 153 | movq %rdx, 8(%rsp) |
71e308a2 | 154 | movq %rbp, %rdi |
16444a8a | 155 | |
48d68b20 | 156 | call ftrace_return_to_handler |
16444a8a | 157 | |
194ec341 | 158 | movq %rax, %rdi |
e71e99c2 | 159 | movq 8(%rsp), %rdx |
16444a8a | 160 | movq (%rsp), %rax |
194ec341 SR |
161 | addq $24, %rsp |
162 | jmp *%rdi | |
48d68b20 | 163 | #endif |
16444a8a | 164 | |
16444a8a | 165 | |
dc37db4d | 166 | #ifndef CONFIG_PREEMPT |
1da177e4 | 167 | #define retint_kernel retint_restore_args |
0bd7b798 | 168 | #endif |
2601e64d | 169 | |
72fe4858 | 170 | #ifdef CONFIG_PARAVIRT |
2be29982 | 171 | ENTRY(native_usergs_sysret64) |
72fe4858 GOC |
172 | swapgs |
173 | sysretq | |
b3baaa13 | 174 | ENDPROC(native_usergs_sysret64) |
72fe4858 GOC |
175 | #endif /* CONFIG_PARAVIRT */ |
176 | ||
2601e64d IM |
177 | |
178 | .macro TRACE_IRQS_IRETQ offset=ARGOFFSET | |
179 | #ifdef CONFIG_TRACE_IRQFLAGS | |
180 | bt $9,EFLAGS-\offset(%rsp) /* interrupts off? */ | |
181 | jnc 1f | |
182 | TRACE_IRQS_ON | |
183 | 1: | |
184 | #endif | |
185 | .endm | |
186 | ||
1da177e4 | 187 | /* |
0bd7b798 AH |
188 | * C code is not supposed to know about undefined top of stack. Every time |
189 | * a C function with an pt_regs argument is called from the SYSCALL based | |
1da177e4 LT |
190 | * fast path FIXUP_TOP_OF_STACK is needed. |
191 | * RESTORE_TOP_OF_STACK syncs the syscall state after any possible ptregs | |
192 | * manipulation. | |
0bd7b798 AH |
193 | */ |
194 | ||
195 | /* %rsp:at FRAMEEND */ | |
c002a1e6 | 196 | .macro FIXUP_TOP_OF_STACK tmp offset=0 |
3d1e42a7 | 197 | movq PER_CPU_VAR(old_rsp),\tmp |
c002a1e6 AH |
198 | movq \tmp,RSP+\offset(%rsp) |
199 | movq $__USER_DS,SS+\offset(%rsp) | |
200 | movq $__USER_CS,CS+\offset(%rsp) | |
201 | movq $-1,RCX+\offset(%rsp) | |
202 | movq R11+\offset(%rsp),\tmp /* get eflags */ | |
203 | movq \tmp,EFLAGS+\offset(%rsp) | |
1da177e4 LT |
204 | .endm |
205 | ||
c002a1e6 AH |
206 | .macro RESTORE_TOP_OF_STACK tmp offset=0 |
207 | movq RSP+\offset(%rsp),\tmp | |
3d1e42a7 | 208 | movq \tmp,PER_CPU_VAR(old_rsp) |
c002a1e6 AH |
209 | movq EFLAGS+\offset(%rsp),\tmp |
210 | movq \tmp,R11+\offset(%rsp) | |
1da177e4 LT |
211 | .endm |
212 | ||
213 | .macro FAKE_STACK_FRAME child_rip | |
214 | /* push in order ss, rsp, eflags, cs, rip */ | |
3829ee6b | 215 | xorl %eax, %eax |
df5d1874 | 216 | pushq_cfi $__KERNEL_DS /* ss */ |
7effaa88 | 217 | /*CFI_REL_OFFSET ss,0*/ |
df5d1874 | 218 | pushq_cfi %rax /* rsp */ |
7effaa88 | 219 | CFI_REL_OFFSET rsp,0 |
df5d1874 | 220 | pushq_cfi $X86_EFLAGS_IF /* eflags - interrupts on */ |
7effaa88 | 221 | /*CFI_REL_OFFSET rflags,0*/ |
df5d1874 | 222 | pushq_cfi $__KERNEL_CS /* cs */ |
7effaa88 | 223 | /*CFI_REL_OFFSET cs,0*/ |
df5d1874 | 224 | pushq_cfi \child_rip /* rip */ |
7effaa88 | 225 | CFI_REL_OFFSET rip,0 |
df5d1874 | 226 | pushq_cfi %rax /* orig rax */ |
1da177e4 LT |
227 | .endm |
228 | ||
229 | .macro UNFAKE_STACK_FRAME | |
230 | addq $8*6, %rsp | |
231 | CFI_ADJUST_CFA_OFFSET -(6*8) | |
232 | .endm | |
233 | ||
dcd072e2 AH |
234 | /* |
235 | * initial frame state for interrupts (and exceptions without error code) | |
236 | */ | |
237 | .macro EMPTY_FRAME start=1 offset=0 | |
7effaa88 | 238 | .if \start |
dcd072e2 | 239 | CFI_STARTPROC simple |
adf14236 | 240 | CFI_SIGNAL_FRAME |
dcd072e2 | 241 | CFI_DEF_CFA rsp,8+\offset |
7effaa88 | 242 | .else |
dcd072e2 | 243 | CFI_DEF_CFA_OFFSET 8+\offset |
7effaa88 | 244 | .endif |
1da177e4 | 245 | .endm |
d99015b1 AH |
246 | |
247 | /* | |
dcd072e2 | 248 | * initial frame state for interrupts (and exceptions without error code) |
d99015b1 | 249 | */ |
dcd072e2 | 250 | .macro INTR_FRAME start=1 offset=0 |
e8a0e276 IM |
251 | EMPTY_FRAME \start, SS+8+\offset-RIP |
252 | /*CFI_REL_OFFSET ss, SS+\offset-RIP*/ | |
253 | CFI_REL_OFFSET rsp, RSP+\offset-RIP | |
254 | /*CFI_REL_OFFSET rflags, EFLAGS+\offset-RIP*/ | |
255 | /*CFI_REL_OFFSET cs, CS+\offset-RIP*/ | |
256 | CFI_REL_OFFSET rip, RIP+\offset-RIP | |
d99015b1 AH |
257 | .endm |
258 | ||
d99015b1 AH |
259 | /* |
260 | * initial frame state for exceptions with error code (and interrupts | |
261 | * with vector already pushed) | |
262 | */ | |
dcd072e2 | 263 | .macro XCPT_FRAME start=1 offset=0 |
e8a0e276 | 264 | INTR_FRAME \start, RIP+\offset-ORIG_RAX |
dcd072e2 AH |
265 | /*CFI_REL_OFFSET orig_rax, ORIG_RAX-ORIG_RAX*/ |
266 | .endm | |
267 | ||
268 | /* | |
269 | * frame that enables calling into C. | |
270 | */ | |
271 | .macro PARTIAL_FRAME start=1 offset=0 | |
e8a0e276 IM |
272 | XCPT_FRAME \start, ORIG_RAX+\offset-ARGOFFSET |
273 | CFI_REL_OFFSET rdi, RDI+\offset-ARGOFFSET | |
274 | CFI_REL_OFFSET rsi, RSI+\offset-ARGOFFSET | |
275 | CFI_REL_OFFSET rdx, RDX+\offset-ARGOFFSET | |
276 | CFI_REL_OFFSET rcx, RCX+\offset-ARGOFFSET | |
277 | CFI_REL_OFFSET rax, RAX+\offset-ARGOFFSET | |
278 | CFI_REL_OFFSET r8, R8+\offset-ARGOFFSET | |
279 | CFI_REL_OFFSET r9, R9+\offset-ARGOFFSET | |
280 | CFI_REL_OFFSET r10, R10+\offset-ARGOFFSET | |
281 | CFI_REL_OFFSET r11, R11+\offset-ARGOFFSET | |
dcd072e2 AH |
282 | .endm |
283 | ||
284 | /* | |
285 | * frame that enables passing a complete pt_regs to a C function. | |
286 | */ | |
287 | .macro DEFAULT_FRAME start=1 offset=0 | |
e8a0e276 | 288 | PARTIAL_FRAME \start, R11+\offset-R15 |
dcd072e2 AH |
289 | CFI_REL_OFFSET rbx, RBX+\offset |
290 | CFI_REL_OFFSET rbp, RBP+\offset | |
291 | CFI_REL_OFFSET r12, R12+\offset | |
292 | CFI_REL_OFFSET r13, R13+\offset | |
293 | CFI_REL_OFFSET r14, R14+\offset | |
294 | CFI_REL_OFFSET r15, R15+\offset | |
295 | .endm | |
d99015b1 AH |
296 | |
297 | /* save partial stack frame */ | |
de31ec8a | 298 | .pushsection .kprobes.text, "ax" |
d99015b1 AH |
299 | ENTRY(save_args) |
300 | XCPT_FRAME | |
301 | cld | |
625dbc3b FW |
302 | /* |
303 | * start from rbp in pt_regs and jump over | |
304 | * return address. | |
305 | */ | |
306 | movq_cfi rdi, RDI+8-RBP | |
307 | movq_cfi rsi, RSI+8-RBP | |
308 | movq_cfi rdx, RDX+8-RBP | |
309 | movq_cfi rcx, RCX+8-RBP | |
310 | movq_cfi rax, RAX+8-RBP | |
311 | movq_cfi r8, R8+8-RBP | |
312 | movq_cfi r9, R9+8-RBP | |
313 | movq_cfi r10, R10+8-RBP | |
314 | movq_cfi r11, R11+8-RBP | |
315 | ||
316 | leaq -RBP+8(%rsp),%rdi /* arg1 for handler */ | |
14ae22ba | 317 | movq_cfi rbp, 8 /* push %rbp */ |
d99015b1 AH |
318 | leaq 8(%rsp), %rbp /* mov %rsp, %ebp */ |
319 | testl $3, CS(%rdi) | |
320 | je 1f | |
321 | SWAPGS | |
322 | /* | |
56895530 | 323 | * irq_count is used to check if a CPU is already on an interrupt stack |
d99015b1 AH |
324 | * or not. While this is essentially redundant with preempt_count it is |
325 | * a little cheaper to use a separate counter in the PDA (short of | |
326 | * moving irq_enter into assembly, which would be too much work) | |
327 | */ | |
56895530 | 328 | 1: incl PER_CPU_VAR(irq_count) |
d99015b1 | 329 | jne 2f |
14ae22ba | 330 | popq_cfi %rax /* move return address... */ |
26f80bd6 | 331 | mov PER_CPU_VAR(irq_stack_ptr),%rsp |
dcd072e2 | 332 | EMPTY_FRAME 0 |
a67798cd | 333 | pushq_cfi %rbp /* backlink for unwinder */ |
14ae22ba | 334 | pushq_cfi %rax /* ... to the new stack */ |
d99015b1 AH |
335 | /* |
336 | * We entered an interrupt context - irqs are off: | |
337 | */ | |
338 | 2: TRACE_IRQS_OFF | |
339 | ret | |
340 | CFI_ENDPROC | |
341 | END(save_args) | |
de31ec8a | 342 | .popsection |
d99015b1 | 343 | |
c002a1e6 AH |
344 | ENTRY(save_rest) |
345 | PARTIAL_FRAME 1 REST_SKIP+8 | |
346 | movq 5*8+16(%rsp), %r11 /* save return address */ | |
347 | movq_cfi rbx, RBX+16 | |
348 | movq_cfi rbp, RBP+16 | |
349 | movq_cfi r12, R12+16 | |
350 | movq_cfi r13, R13+16 | |
351 | movq_cfi r14, R14+16 | |
352 | movq_cfi r15, R15+16 | |
353 | movq %r11, 8(%rsp) /* return address */ | |
354 | FIXUP_TOP_OF_STACK %r11, 16 | |
355 | ret | |
356 | CFI_ENDPROC | |
357 | END(save_rest) | |
358 | ||
e2f6bc25 | 359 | /* save complete stack frame */ |
c2810188 | 360 | .pushsection .kprobes.text, "ax" |
e2f6bc25 AH |
361 | ENTRY(save_paranoid) |
362 | XCPT_FRAME 1 RDI+8 | |
363 | cld | |
364 | movq_cfi rdi, RDI+8 | |
365 | movq_cfi rsi, RSI+8 | |
366 | movq_cfi rdx, RDX+8 | |
367 | movq_cfi rcx, RCX+8 | |
368 | movq_cfi rax, RAX+8 | |
369 | movq_cfi r8, R8+8 | |
370 | movq_cfi r9, R9+8 | |
371 | movq_cfi r10, R10+8 | |
372 | movq_cfi r11, R11+8 | |
373 | movq_cfi rbx, RBX+8 | |
374 | movq_cfi rbp, RBP+8 | |
375 | movq_cfi r12, R12+8 | |
376 | movq_cfi r13, R13+8 | |
377 | movq_cfi r14, R14+8 | |
378 | movq_cfi r15, R15+8 | |
379 | movl $1,%ebx | |
380 | movl $MSR_GS_BASE,%ecx | |
381 | rdmsr | |
382 | testl %edx,%edx | |
383 | js 1f /* negative -> in kernel */ | |
384 | SWAPGS | |
385 | xorl %ebx,%ebx | |
386 | 1: ret | |
387 | CFI_ENDPROC | |
388 | END(save_paranoid) | |
c2810188 | 389 | .popsection |
e2f6bc25 | 390 | |
1da177e4 | 391 | /* |
5b3eec0c IM |
392 | * A newly forked process directly context switches into this address. |
393 | * | |
394 | * rdi: prev task we switched from | |
0bd7b798 | 395 | */ |
1da177e4 | 396 | ENTRY(ret_from_fork) |
dcd072e2 | 397 | DEFAULT_FRAME |
5b3eec0c | 398 | |
7106a5ab BL |
399 | LOCK ; btr $TIF_FORK,TI_flags(%r8) |
400 | ||
df5d1874 JB |
401 | pushq_cfi kernel_eflags(%rip) |
402 | popfq_cfi # reset kernel eflags | |
5b3eec0c IM |
403 | |
404 | call schedule_tail # rdi: 'prev' task parameter | |
405 | ||
1da177e4 | 406 | GET_THREAD_INFO(%rcx) |
5b3eec0c | 407 | |
1da177e4 | 408 | RESTORE_REST |
5b3eec0c IM |
409 | |
410 | testl $3, CS-ARGOFFSET(%rsp) # from kernel_thread? | |
1da177e4 | 411 | je int_ret_from_sys_call |
5b3eec0c IM |
412 | |
413 | testl $_TIF_IA32, TI_flags(%rcx) # 32-bit compat task needs IRET | |
1da177e4 | 414 | jnz int_ret_from_sys_call |
5b3eec0c | 415 | |
c002a1e6 | 416 | RESTORE_TOP_OF_STACK %rdi, -ARGOFFSET |
5b3eec0c IM |
417 | jmp ret_from_sys_call # go to the SYSRET fastpath |
418 | ||
1da177e4 | 419 | CFI_ENDPROC |
4b787e0b | 420 | END(ret_from_fork) |
1da177e4 LT |
421 | |
422 | /* | |
423 | * System call entry. Upto 6 arguments in registers are supported. | |
424 | * | |
425 | * SYSCALL does not save anything on the stack and does not change the | |
426 | * stack pointer. | |
427 | */ | |
0bd7b798 | 428 | |
1da177e4 | 429 | /* |
0bd7b798 | 430 | * Register setup: |
1da177e4 LT |
431 | * rax system call number |
432 | * rdi arg0 | |
0bd7b798 | 433 | * rcx return address for syscall/sysret, C arg3 |
1da177e4 | 434 | * rsi arg1 |
0bd7b798 | 435 | * rdx arg2 |
1da177e4 LT |
436 | * r10 arg3 (--> moved to rcx for C) |
437 | * r8 arg4 | |
438 | * r9 arg5 | |
439 | * r11 eflags for syscall/sysret, temporary for C | |
0bd7b798 AH |
440 | * r12-r15,rbp,rbx saved by C code, not touched. |
441 | * | |
1da177e4 LT |
442 | * Interrupts are off on entry. |
443 | * Only called from user space. | |
444 | * | |
445 | * XXX if we had a free scratch register we could save the RSP into the stack frame | |
446 | * and report it properly in ps. Unfortunately we haven't. | |
7bf36bbc AK |
447 | * |
448 | * When user can change the frames always force IRET. That is because | |
449 | * it deals with uncanonical addresses better. SYSRET has trouble | |
450 | * with them due to bugs in both AMD and Intel CPUs. | |
0bd7b798 | 451 | */ |
1da177e4 LT |
452 | |
453 | ENTRY(system_call) | |
7effaa88 | 454 | CFI_STARTPROC simple |
adf14236 | 455 | CFI_SIGNAL_FRAME |
9af45651 | 456 | CFI_DEF_CFA rsp,KERNEL_STACK_OFFSET |
7effaa88 JB |
457 | CFI_REGISTER rip,rcx |
458 | /*CFI_REGISTER rflags,r11*/ | |
72fe4858 GOC |
459 | SWAPGS_UNSAFE_STACK |
460 | /* | |
461 | * A hypervisor implementation might want to use a label | |
462 | * after the swapgs, so that it can do the swapgs | |
463 | * for the guest and jump here on syscall. | |
464 | */ | |
465 | ENTRY(system_call_after_swapgs) | |
466 | ||
3d1e42a7 | 467 | movq %rsp,PER_CPU_VAR(old_rsp) |
9af45651 | 468 | movq PER_CPU_VAR(kernel_stack),%rsp |
2601e64d IM |
469 | /* |
470 | * No need to follow this irqs off/on section - it's straight | |
471 | * and short: | |
472 | */ | |
72fe4858 | 473 | ENABLE_INTERRUPTS(CLBR_NONE) |
1da177e4 | 474 | SAVE_ARGS 8,1 |
0bd7b798 | 475 | movq %rax,ORIG_RAX-ARGOFFSET(%rsp) |
7effaa88 JB |
476 | movq %rcx,RIP-ARGOFFSET(%rsp) |
477 | CFI_REL_OFFSET rip,RIP-ARGOFFSET | |
1da177e4 | 478 | GET_THREAD_INFO(%rcx) |
d4d67150 | 479 | testl $_TIF_WORK_SYSCALL_ENTRY,TI_flags(%rcx) |
1da177e4 | 480 | jnz tracesys |
86a1c34a | 481 | system_call_fastpath: |
1da177e4 LT |
482 | cmpq $__NR_syscall_max,%rax |
483 | ja badsys | |
484 | movq %r10,%rcx | |
485 | call *sys_call_table(,%rax,8) # XXX: rip relative | |
486 | movq %rax,RAX-ARGOFFSET(%rsp) | |
487 | /* | |
488 | * Syscall return path ending with SYSRET (fast path) | |
0bd7b798 AH |
489 | * Has incomplete stack frame and undefined top of stack. |
490 | */ | |
1da177e4 | 491 | ret_from_sys_call: |
11b854b2 | 492 | movl $_TIF_ALLWORK_MASK,%edi |
1da177e4 | 493 | /* edi: flagmask */ |
0bd7b798 | 494 | sysret_check: |
10cd706d | 495 | LOCKDEP_SYS_EXIT |
1da177e4 | 496 | GET_THREAD_INFO(%rcx) |
72fe4858 | 497 | DISABLE_INTERRUPTS(CLBR_NONE) |
2601e64d | 498 | TRACE_IRQS_OFF |
26ccb8a7 | 499 | movl TI_flags(%rcx),%edx |
1da177e4 | 500 | andl %edi,%edx |
0bd7b798 | 501 | jnz sysret_careful |
bcddc015 | 502 | CFI_REMEMBER_STATE |
2601e64d IM |
503 | /* |
504 | * sysretq will re-enable interrupts: | |
505 | */ | |
506 | TRACE_IRQS_ON | |
1da177e4 | 507 | movq RIP-ARGOFFSET(%rsp),%rcx |
7effaa88 | 508 | CFI_REGISTER rip,rcx |
1da177e4 | 509 | RESTORE_ARGS 0,-ARG_SKIP,1 |
7effaa88 | 510 | /*CFI_REGISTER rflags,r11*/ |
3d1e42a7 | 511 | movq PER_CPU_VAR(old_rsp), %rsp |
2be29982 | 512 | USERGS_SYSRET64 |
1da177e4 | 513 | |
bcddc015 | 514 | CFI_RESTORE_STATE |
1da177e4 | 515 | /* Handle reschedules */ |
0bd7b798 | 516 | /* edx: work, edi: workmask */ |
1da177e4 LT |
517 | sysret_careful: |
518 | bt $TIF_NEED_RESCHED,%edx | |
519 | jnc sysret_signal | |
2601e64d | 520 | TRACE_IRQS_ON |
72fe4858 | 521 | ENABLE_INTERRUPTS(CLBR_NONE) |
df5d1874 | 522 | pushq_cfi %rdi |
1da177e4 | 523 | call schedule |
df5d1874 | 524 | popq_cfi %rdi |
1da177e4 LT |
525 | jmp sysret_check |
526 | ||
0bd7b798 | 527 | /* Handle a signal */ |
1da177e4 | 528 | sysret_signal: |
2601e64d | 529 | TRACE_IRQS_ON |
72fe4858 | 530 | ENABLE_INTERRUPTS(CLBR_NONE) |
86a1c34a RM |
531 | #ifdef CONFIG_AUDITSYSCALL |
532 | bt $TIF_SYSCALL_AUDIT,%edx | |
533 | jc sysret_audit | |
534 | #endif | |
b60e714d RM |
535 | /* |
536 | * We have a signal, or exit tracing or single-step. | |
537 | * These all wind up with the iret return path anyway, | |
538 | * so just join that path right now. | |
539 | */ | |
540 | FIXUP_TOP_OF_STACK %r11, -ARGOFFSET | |
541 | jmp int_check_syscall_exit_work | |
0bd7b798 | 542 | |
7effaa88 JB |
543 | badsys: |
544 | movq $-ENOSYS,RAX-ARGOFFSET(%rsp) | |
545 | jmp ret_from_sys_call | |
546 | ||
86a1c34a RM |
547 | #ifdef CONFIG_AUDITSYSCALL |
548 | /* | |
549 | * Fast path for syscall audit without full syscall trace. | |
550 | * We just call audit_syscall_entry() directly, and then | |
551 | * jump back to the normal fast path. | |
552 | */ | |
553 | auditsys: | |
554 | movq %r10,%r9 /* 6th arg: 4th syscall arg */ | |
555 | movq %rdx,%r8 /* 5th arg: 3rd syscall arg */ | |
556 | movq %rsi,%rcx /* 4th arg: 2nd syscall arg */ | |
557 | movq %rdi,%rdx /* 3rd arg: 1st syscall arg */ | |
558 | movq %rax,%rsi /* 2nd arg: syscall number */ | |
559 | movl $AUDIT_ARCH_X86_64,%edi /* 1st arg: audit arch */ | |
560 | call audit_syscall_entry | |
561 | LOAD_ARGS 0 /* reload call-clobbered registers */ | |
562 | jmp system_call_fastpath | |
563 | ||
564 | /* | |
565 | * Return fast path for syscall audit. Call audit_syscall_exit() | |
566 | * directly and then jump back to the fast path with TIF_SYSCALL_AUDIT | |
567 | * masked off. | |
568 | */ | |
569 | sysret_audit: | |
03275591 RM |
570 | movq RAX-ARGOFFSET(%rsp),%rsi /* second arg, syscall return value */ |
571 | cmpq $0,%rsi /* is it < 0? */ | |
86a1c34a RM |
572 | setl %al /* 1 if so, 0 if not */ |
573 | movzbl %al,%edi /* zero-extend that into %edi */ | |
574 | inc %edi /* first arg, 0->1(AUDITSC_SUCCESS), 1->2(AUDITSC_FAILURE) */ | |
575 | call audit_syscall_exit | |
576 | movl $(_TIF_ALLWORK_MASK & ~_TIF_SYSCALL_AUDIT),%edi | |
577 | jmp sysret_check | |
578 | #endif /* CONFIG_AUDITSYSCALL */ | |
579 | ||
1da177e4 | 580 | /* Do syscall tracing */ |
0bd7b798 | 581 | tracesys: |
86a1c34a RM |
582 | #ifdef CONFIG_AUDITSYSCALL |
583 | testl $(_TIF_WORK_SYSCALL_ENTRY & ~_TIF_SYSCALL_AUDIT),TI_flags(%rcx) | |
584 | jz auditsys | |
585 | #endif | |
1da177e4 | 586 | SAVE_REST |
a31f8dd7 | 587 | movq $-ENOSYS,RAX(%rsp) /* ptrace can change this for a bad syscall */ |
1da177e4 LT |
588 | FIXUP_TOP_OF_STACK %rdi |
589 | movq %rsp,%rdi | |
590 | call syscall_trace_enter | |
d4d67150 RM |
591 | /* |
592 | * Reload arg registers from stack in case ptrace changed them. | |
593 | * We don't reload %rax because syscall_trace_enter() returned | |
594 | * the value it wants us to use in the table lookup. | |
595 | */ | |
596 | LOAD_ARGS ARGOFFSET, 1 | |
1da177e4 LT |
597 | RESTORE_REST |
598 | cmpq $__NR_syscall_max,%rax | |
a31f8dd7 | 599 | ja int_ret_from_sys_call /* RAX(%rsp) set to -ENOSYS above */ |
1da177e4 LT |
600 | movq %r10,%rcx /* fixup for C */ |
601 | call *sys_call_table(,%rax,8) | |
a31f8dd7 | 602 | movq %rax,RAX-ARGOFFSET(%rsp) |
7bf36bbc | 603 | /* Use IRET because user could have changed frame */ |
0bd7b798 AH |
604 | |
605 | /* | |
1da177e4 LT |
606 | * Syscall return path ending with IRET. |
607 | * Has correct top of stack, but partial stack frame. | |
bcddc015 | 608 | */ |
bc8b2b92 | 609 | GLOBAL(int_ret_from_sys_call) |
72fe4858 | 610 | DISABLE_INTERRUPTS(CLBR_NONE) |
2601e64d | 611 | TRACE_IRQS_OFF |
1da177e4 LT |
612 | testl $3,CS-ARGOFFSET(%rsp) |
613 | je retint_restore_args | |
614 | movl $_TIF_ALLWORK_MASK,%edi | |
615 | /* edi: mask to check */ | |
bc8b2b92 | 616 | GLOBAL(int_with_check) |
10cd706d | 617 | LOCKDEP_SYS_EXIT_IRQ |
1da177e4 | 618 | GET_THREAD_INFO(%rcx) |
26ccb8a7 | 619 | movl TI_flags(%rcx),%edx |
1da177e4 LT |
620 | andl %edi,%edx |
621 | jnz int_careful | |
26ccb8a7 | 622 | andl $~TS_COMPAT,TI_status(%rcx) |
1da177e4 LT |
623 | jmp retint_swapgs |
624 | ||
625 | /* Either reschedule or signal or syscall exit tracking needed. */ | |
626 | /* First do a reschedule test. */ | |
627 | /* edx: work, edi: workmask */ | |
628 | int_careful: | |
629 | bt $TIF_NEED_RESCHED,%edx | |
630 | jnc int_very_careful | |
2601e64d | 631 | TRACE_IRQS_ON |
72fe4858 | 632 | ENABLE_INTERRUPTS(CLBR_NONE) |
df5d1874 | 633 | pushq_cfi %rdi |
1da177e4 | 634 | call schedule |
df5d1874 | 635 | popq_cfi %rdi |
72fe4858 | 636 | DISABLE_INTERRUPTS(CLBR_NONE) |
2601e64d | 637 | TRACE_IRQS_OFF |
1da177e4 LT |
638 | jmp int_with_check |
639 | ||
640 | /* handle signals and tracing -- both require a full stack frame */ | |
641 | int_very_careful: | |
2601e64d | 642 | TRACE_IRQS_ON |
72fe4858 | 643 | ENABLE_INTERRUPTS(CLBR_NONE) |
b60e714d | 644 | int_check_syscall_exit_work: |
1da177e4 | 645 | SAVE_REST |
0bd7b798 | 646 | /* Check for syscall exit trace */ |
d4d67150 | 647 | testl $_TIF_WORK_SYSCALL_EXIT,%edx |
1da177e4 | 648 | jz int_signal |
df5d1874 | 649 | pushq_cfi %rdi |
0bd7b798 | 650 | leaq 8(%rsp),%rdi # &ptregs -> arg1 |
1da177e4 | 651 | call syscall_trace_leave |
df5d1874 | 652 | popq_cfi %rdi |
d4d67150 | 653 | andl $~(_TIF_WORK_SYSCALL_EXIT|_TIF_SYSCALL_EMU),%edi |
1da177e4 | 654 | jmp int_restore_rest |
0bd7b798 | 655 | |
1da177e4 | 656 | int_signal: |
8f4d37ec | 657 | testl $_TIF_DO_NOTIFY_MASK,%edx |
1da177e4 LT |
658 | jz 1f |
659 | movq %rsp,%rdi # &ptregs -> arg1 | |
660 | xorl %esi,%esi # oldset -> arg2 | |
661 | call do_notify_resume | |
eca91e78 | 662 | 1: movl $_TIF_WORK_MASK,%edi |
1da177e4 LT |
663 | int_restore_rest: |
664 | RESTORE_REST | |
72fe4858 | 665 | DISABLE_INTERRUPTS(CLBR_NONE) |
2601e64d | 666 | TRACE_IRQS_OFF |
1da177e4 LT |
667 | jmp int_with_check |
668 | CFI_ENDPROC | |
bcddc015 | 669 | END(system_call) |
0bd7b798 AH |
670 | |
671 | /* | |
1da177e4 | 672 | * Certain special system calls that need to save a complete full stack frame. |
0bd7b798 | 673 | */ |
1da177e4 | 674 | .macro PTREGSCALL label,func,arg |
c002a1e6 AH |
675 | ENTRY(\label) |
676 | PARTIAL_FRAME 1 8 /* offset 8: return address */ | |
677 | subq $REST_SKIP, %rsp | |
678 | CFI_ADJUST_CFA_OFFSET REST_SKIP | |
679 | call save_rest | |
680 | DEFAULT_FRAME 0 8 /* offset 8: return address */ | |
681 | leaq 8(%rsp), \arg /* pt_regs pointer */ | |
682 | call \func | |
683 | jmp ptregscall_common | |
684 | CFI_ENDPROC | |
4b787e0b | 685 | END(\label) |
1da177e4 LT |
686 | .endm |
687 | ||
688 | PTREGSCALL stub_clone, sys_clone, %r8 | |
689 | PTREGSCALL stub_fork, sys_fork, %rdi | |
690 | PTREGSCALL stub_vfork, sys_vfork, %rdi | |
1da177e4 LT |
691 | PTREGSCALL stub_sigaltstack, sys_sigaltstack, %rdx |
692 | PTREGSCALL stub_iopl, sys_iopl, %rsi | |
693 | ||
694 | ENTRY(ptregscall_common) | |
c002a1e6 AH |
695 | DEFAULT_FRAME 1 8 /* offset 8: return address */ |
696 | RESTORE_TOP_OF_STACK %r11, 8 | |
697 | movq_cfi_restore R15+8, r15 | |
698 | movq_cfi_restore R14+8, r14 | |
699 | movq_cfi_restore R13+8, r13 | |
700 | movq_cfi_restore R12+8, r12 | |
701 | movq_cfi_restore RBP+8, rbp | |
702 | movq_cfi_restore RBX+8, rbx | |
703 | ret $REST_SKIP /* pop extended registers */ | |
1da177e4 | 704 | CFI_ENDPROC |
4b787e0b | 705 | END(ptregscall_common) |
0bd7b798 | 706 | |
1da177e4 LT |
707 | ENTRY(stub_execve) |
708 | CFI_STARTPROC | |
e6b04b6b JB |
709 | addq $8, %rsp |
710 | PARTIAL_FRAME 0 | |
1da177e4 | 711 | SAVE_REST |
1da177e4 | 712 | FIXUP_TOP_OF_STACK %r11 |
5d119b2c | 713 | movq %rsp, %rcx |
1da177e4 | 714 | call sys_execve |
1da177e4 | 715 | RESTORE_TOP_OF_STACK %r11 |
1da177e4 LT |
716 | movq %rax,RAX(%rsp) |
717 | RESTORE_REST | |
718 | jmp int_ret_from_sys_call | |
719 | CFI_ENDPROC | |
4b787e0b | 720 | END(stub_execve) |
0bd7b798 | 721 | |
1da177e4 LT |
722 | /* |
723 | * sigreturn is special because it needs to restore all registers on return. | |
724 | * This cannot be done with SYSRET, so use the IRET return path instead. | |
0bd7b798 | 725 | */ |
1da177e4 LT |
726 | ENTRY(stub_rt_sigreturn) |
727 | CFI_STARTPROC | |
7effaa88 | 728 | addq $8, %rsp |
e6b04b6b | 729 | PARTIAL_FRAME 0 |
1da177e4 LT |
730 | SAVE_REST |
731 | movq %rsp,%rdi | |
732 | FIXUP_TOP_OF_STACK %r11 | |
733 | call sys_rt_sigreturn | |
734 | movq %rax,RAX(%rsp) # fixme, this could be done at the higher layer | |
735 | RESTORE_REST | |
736 | jmp int_ret_from_sys_call | |
737 | CFI_ENDPROC | |
4b787e0b | 738 | END(stub_rt_sigreturn) |
1da177e4 | 739 | |
939b7871 PA |
740 | /* |
741 | * Build the entry stubs and pointer table with some assembler magic. | |
742 | * We pack 7 stubs into a single 32-byte chunk, which will fit in a | |
743 | * single cache line on all modern x86 implementations. | |
744 | */ | |
745 | .section .init.rodata,"a" | |
746 | ENTRY(interrupt) | |
747 | .text | |
748 | .p2align 5 | |
749 | .p2align CONFIG_X86_L1_CACHE_SHIFT | |
750 | ENTRY(irq_entries_start) | |
751 | INTR_FRAME | |
752 | vector=FIRST_EXTERNAL_VECTOR | |
753 | .rept (NR_VECTORS-FIRST_EXTERNAL_VECTOR+6)/7 | |
754 | .balign 32 | |
755 | .rept 7 | |
756 | .if vector < NR_VECTORS | |
8665596e | 757 | .if vector <> FIRST_EXTERNAL_VECTOR |
939b7871 PA |
758 | CFI_ADJUST_CFA_OFFSET -8 |
759 | .endif | |
df5d1874 | 760 | 1: pushq_cfi $(~vector+0x80) /* Note: always in signed byte range */ |
8665596e | 761 | .if ((vector-FIRST_EXTERNAL_VECTOR)%7) <> 6 |
939b7871 PA |
762 | jmp 2f |
763 | .endif | |
764 | .previous | |
765 | .quad 1b | |
766 | .text | |
767 | vector=vector+1 | |
768 | .endif | |
769 | .endr | |
770 | 2: jmp common_interrupt | |
771 | .endr | |
772 | CFI_ENDPROC | |
773 | END(irq_entries_start) | |
774 | ||
775 | .previous | |
776 | END(interrupt) | |
777 | .previous | |
778 | ||
d99015b1 | 779 | /* |
1da177e4 LT |
780 | * Interrupt entry/exit. |
781 | * | |
782 | * Interrupt entry points save only callee clobbered registers in fast path. | |
d99015b1 AH |
783 | * |
784 | * Entry runs with interrupts off. | |
785 | */ | |
1da177e4 | 786 | |
722024db | 787 | /* 0(%rsp): ~(interrupt number) */ |
1da177e4 | 788 | .macro interrupt func |
625dbc3b FW |
789 | /* reserve pt_regs for scratch regs and rbp */ |
790 | subq $ORIG_RAX-RBP, %rsp | |
791 | CFI_ADJUST_CFA_OFFSET ORIG_RAX-RBP | |
d99015b1 | 792 | call save_args |
dcd072e2 | 793 | PARTIAL_FRAME 0 |
1da177e4 LT |
794 | call \func |
795 | .endm | |
796 | ||
8222d718 MH |
797 | /* |
798 | * Interrupt entry/exit should be protected against kprobes | |
799 | */ | |
800 | .pushsection .kprobes.text, "ax" | |
722024db AH |
801 | /* |
802 | * The interrupt stubs push (~vector+0x80) onto the stack and | |
803 | * then jump to common_interrupt. | |
804 | */ | |
939b7871 PA |
805 | .p2align CONFIG_X86_L1_CACHE_SHIFT |
806 | common_interrupt: | |
7effaa88 | 807 | XCPT_FRAME |
722024db | 808 | addq $-0x80,(%rsp) /* Adjust vector to [-256,-1] range */ |
1da177e4 | 809 | interrupt do_IRQ |
3d1e42a7 | 810 | /* 0(%rsp): old_rsp-ARGOFFSET */ |
7effaa88 | 811 | ret_from_intr: |
72fe4858 | 812 | DISABLE_INTERRUPTS(CLBR_NONE) |
2601e64d | 813 | TRACE_IRQS_OFF |
56895530 | 814 | decl PER_CPU_VAR(irq_count) |
1de9c3f6 | 815 | leaveq |
625dbc3b | 816 | |
df5d1874 | 817 | CFI_RESTORE rbp |
7effaa88 | 818 | CFI_DEF_CFA_REGISTER rsp |
1de9c3f6 | 819 | CFI_ADJUST_CFA_OFFSET -8 |
625dbc3b FW |
820 | |
821 | /* we did not save rbx, restore only from ARGOFFSET */ | |
822 | addq $8, %rsp | |
823 | CFI_ADJUST_CFA_OFFSET -8 | |
7effaa88 | 824 | exit_intr: |
1da177e4 LT |
825 | GET_THREAD_INFO(%rcx) |
826 | testl $3,CS-ARGOFFSET(%rsp) | |
827 | je retint_kernel | |
0bd7b798 | 828 | |
1da177e4 LT |
829 | /* Interrupt came from user space */ |
830 | /* | |
831 | * Has a correct top of stack, but a partial stack frame | |
832 | * %rcx: thread info. Interrupts off. | |
0bd7b798 | 833 | */ |
1da177e4 LT |
834 | retint_with_reschedule: |
835 | movl $_TIF_WORK_MASK,%edi | |
7effaa88 | 836 | retint_check: |
10cd706d | 837 | LOCKDEP_SYS_EXIT_IRQ |
26ccb8a7 | 838 | movl TI_flags(%rcx),%edx |
1da177e4 | 839 | andl %edi,%edx |
7effaa88 | 840 | CFI_REMEMBER_STATE |
1da177e4 | 841 | jnz retint_careful |
10cd706d PZ |
842 | |
843 | retint_swapgs: /* return to user-space */ | |
2601e64d IM |
844 | /* |
845 | * The iretq could re-enable interrupts: | |
846 | */ | |
72fe4858 | 847 | DISABLE_INTERRUPTS(CLBR_ANY) |
2601e64d | 848 | TRACE_IRQS_IRETQ |
72fe4858 | 849 | SWAPGS |
2601e64d IM |
850 | jmp restore_args |
851 | ||
10cd706d | 852 | retint_restore_args: /* return to kernel space */ |
72fe4858 | 853 | DISABLE_INTERRUPTS(CLBR_ANY) |
2601e64d IM |
854 | /* |
855 | * The iretq could re-enable interrupts: | |
856 | */ | |
857 | TRACE_IRQS_IRETQ | |
858 | restore_args: | |
3701d863 IM |
859 | RESTORE_ARGS 0,8,0 |
860 | ||
f7f3d791 | 861 | irq_return: |
72fe4858 | 862 | INTERRUPT_RETURN |
3701d863 IM |
863 | |
864 | .section __ex_table, "a" | |
865 | .quad irq_return, bad_iret | |
866 | .previous | |
867 | ||
868 | #ifdef CONFIG_PARAVIRT | |
72fe4858 | 869 | ENTRY(native_iret) |
1da177e4 LT |
870 | iretq |
871 | ||
872 | .section __ex_table,"a" | |
72fe4858 | 873 | .quad native_iret, bad_iret |
1da177e4 | 874 | .previous |
3701d863 IM |
875 | #endif |
876 | ||
1da177e4 | 877 | .section .fixup,"ax" |
1da177e4 | 878 | bad_iret: |
3aa4b37d RM |
879 | /* |
880 | * The iret traps when the %cs or %ss being restored is bogus. | |
881 | * We've lost the original trap vector and error code. | |
882 | * #GPF is the most likely one to get for an invalid selector. | |
883 | * So pretend we completed the iret and took the #GPF in user mode. | |
884 | * | |
885 | * We are now running with the kernel GS after exception recovery. | |
886 | * But error_entry expects us to have user GS to match the user %cs, | |
887 | * so swap back. | |
888 | */ | |
889 | pushq $0 | |
890 | ||
891 | SWAPGS | |
892 | jmp general_protection | |
893 | ||
72fe4858 GOC |
894 | .previous |
895 | ||
7effaa88 | 896 | /* edi: workmask, edx: work */ |
1da177e4 | 897 | retint_careful: |
7effaa88 | 898 | CFI_RESTORE_STATE |
1da177e4 LT |
899 | bt $TIF_NEED_RESCHED,%edx |
900 | jnc retint_signal | |
2601e64d | 901 | TRACE_IRQS_ON |
72fe4858 | 902 | ENABLE_INTERRUPTS(CLBR_NONE) |
df5d1874 | 903 | pushq_cfi %rdi |
1da177e4 | 904 | call schedule |
df5d1874 | 905 | popq_cfi %rdi |
1da177e4 | 906 | GET_THREAD_INFO(%rcx) |
72fe4858 | 907 | DISABLE_INTERRUPTS(CLBR_NONE) |
2601e64d | 908 | TRACE_IRQS_OFF |
1da177e4 | 909 | jmp retint_check |
0bd7b798 | 910 | |
1da177e4 | 911 | retint_signal: |
8f4d37ec | 912 | testl $_TIF_DO_NOTIFY_MASK,%edx |
10ffdbb8 | 913 | jz retint_swapgs |
2601e64d | 914 | TRACE_IRQS_ON |
72fe4858 | 915 | ENABLE_INTERRUPTS(CLBR_NONE) |
1da177e4 | 916 | SAVE_REST |
0bd7b798 | 917 | movq $-1,ORIG_RAX(%rsp) |
3829ee6b | 918 | xorl %esi,%esi # oldset |
1da177e4 LT |
919 | movq %rsp,%rdi # &pt_regs |
920 | call do_notify_resume | |
921 | RESTORE_REST | |
72fe4858 | 922 | DISABLE_INTERRUPTS(CLBR_NONE) |
2601e64d | 923 | TRACE_IRQS_OFF |
be9e6870 | 924 | GET_THREAD_INFO(%rcx) |
eca91e78 | 925 | jmp retint_with_reschedule |
1da177e4 LT |
926 | |
927 | #ifdef CONFIG_PREEMPT | |
928 | /* Returning to kernel space. Check if we need preemption */ | |
929 | /* rcx: threadinfo. interrupts off. */ | |
b06babac | 930 | ENTRY(retint_kernel) |
26ccb8a7 | 931 | cmpl $0,TI_preempt_count(%rcx) |
1da177e4 | 932 | jnz retint_restore_args |
26ccb8a7 | 933 | bt $TIF_NEED_RESCHED,TI_flags(%rcx) |
1da177e4 LT |
934 | jnc retint_restore_args |
935 | bt $9,EFLAGS-ARGOFFSET(%rsp) /* interrupts off? */ | |
936 | jnc retint_restore_args | |
937 | call preempt_schedule_irq | |
938 | jmp exit_intr | |
0bd7b798 | 939 | #endif |
4b787e0b | 940 | |
1da177e4 | 941 | CFI_ENDPROC |
4b787e0b | 942 | END(common_interrupt) |
8222d718 MH |
943 | /* |
944 | * End of kprobes section | |
945 | */ | |
946 | .popsection | |
0bd7b798 | 947 | |
1da177e4 LT |
948 | /* |
949 | * APIC interrupts. | |
0bd7b798 | 950 | */ |
322648d1 AH |
951 | .macro apicinterrupt num sym do_sym |
952 | ENTRY(\sym) | |
7effaa88 | 953 | INTR_FRAME |
df5d1874 | 954 | pushq_cfi $~(\num) |
322648d1 | 955 | interrupt \do_sym |
1da177e4 LT |
956 | jmp ret_from_intr |
957 | CFI_ENDPROC | |
322648d1 AH |
958 | END(\sym) |
959 | .endm | |
1da177e4 | 960 | |
322648d1 AH |
961 | #ifdef CONFIG_SMP |
962 | apicinterrupt IRQ_MOVE_CLEANUP_VECTOR \ | |
963 | irq_move_cleanup_interrupt smp_irq_move_cleanup_interrupt | |
4ef702c1 AK |
964 | apicinterrupt REBOOT_VECTOR \ |
965 | reboot_interrupt smp_reboot_interrupt | |
322648d1 | 966 | #endif |
1da177e4 | 967 | |
03b48632 | 968 | #ifdef CONFIG_X86_UV |
5ae3a139 | 969 | apicinterrupt UV_BAU_MESSAGE \ |
322648d1 | 970 | uv_bau_message_intr1 uv_bau_message_interrupt |
03b48632 | 971 | #endif |
322648d1 AH |
972 | apicinterrupt LOCAL_TIMER_VECTOR \ |
973 | apic_timer_interrupt smp_apic_timer_interrupt | |
4a4de9c7 DS |
974 | apicinterrupt X86_PLATFORM_IPI_VECTOR \ |
975 | x86_platform_ipi smp_x86_platform_ipi | |
89b831ef | 976 | |
0bd7b798 | 977 | #ifdef CONFIG_SMP |
3234282f JB |
978 | .irpc idx, "01234567" |
979 | apicinterrupt (INVALIDATE_TLB_VECTOR_START)+\idx \ | |
980 | invalidate_interrupt\idx smp_invalidate_interrupt | |
981 | .endr | |
1da177e4 LT |
982 | #endif |
983 | ||
322648d1 | 984 | apicinterrupt THRESHOLD_APIC_VECTOR \ |
7856f6cc | 985 | threshold_interrupt smp_threshold_interrupt |
322648d1 AH |
986 | apicinterrupt THERMAL_APIC_VECTOR \ |
987 | thermal_interrupt smp_thermal_interrupt | |
1812924b | 988 | |
ccc3c319 AK |
989 | #ifdef CONFIG_X86_MCE |
990 | apicinterrupt MCE_SELF_VECTOR \ | |
991 | mce_self_interrupt smp_mce_self_interrupt | |
992 | #endif | |
993 | ||
322648d1 AH |
994 | #ifdef CONFIG_SMP |
995 | apicinterrupt CALL_FUNCTION_SINGLE_VECTOR \ | |
996 | call_function_single_interrupt smp_call_function_single_interrupt | |
997 | apicinterrupt CALL_FUNCTION_VECTOR \ | |
998 | call_function_interrupt smp_call_function_interrupt | |
999 | apicinterrupt RESCHEDULE_VECTOR \ | |
1000 | reschedule_interrupt smp_reschedule_interrupt | |
1001 | #endif | |
1da177e4 | 1002 | |
322648d1 AH |
1003 | apicinterrupt ERROR_APIC_VECTOR \ |
1004 | error_interrupt smp_error_interrupt | |
1005 | apicinterrupt SPURIOUS_APIC_VECTOR \ | |
1006 | spurious_interrupt smp_spurious_interrupt | |
0bd7b798 | 1007 | |
e360adbe PZ |
1008 | #ifdef CONFIG_IRQ_WORK |
1009 | apicinterrupt IRQ_WORK_VECTOR \ | |
1010 | irq_work_interrupt smp_irq_work_interrupt | |
241771ef IM |
1011 | #endif |
1012 | ||
1da177e4 LT |
1013 | /* |
1014 | * Exception entry points. | |
0bd7b798 | 1015 | */ |
322648d1 AH |
1016 | .macro zeroentry sym do_sym |
1017 | ENTRY(\sym) | |
7effaa88 | 1018 | INTR_FRAME |
fab58420 | 1019 | PARAVIRT_ADJUST_EXCEPTION_FRAME |
14ae22ba | 1020 | pushq_cfi $-1 /* ORIG_RAX: no syscall to restart */ |
b1cccb1b JB |
1021 | subq $ORIG_RAX-R15, %rsp |
1022 | CFI_ADJUST_CFA_OFFSET ORIG_RAX-R15 | |
d99015b1 | 1023 | call error_entry |
dcd072e2 | 1024 | DEFAULT_FRAME 0 |
d99015b1 AH |
1025 | movq %rsp,%rdi /* pt_regs pointer */ |
1026 | xorl %esi,%esi /* no error code */ | |
322648d1 | 1027 | call \do_sym |
d99015b1 | 1028 | jmp error_exit /* %ebx: no swapgs flag */ |
7effaa88 | 1029 | CFI_ENDPROC |
322648d1 AH |
1030 | END(\sym) |
1031 | .endm | |
1da177e4 | 1032 | |
322648d1 | 1033 | .macro paranoidzeroentry sym do_sym |
ddeb8f21 | 1034 | ENTRY(\sym) |
b8b1d08b AH |
1035 | INTR_FRAME |
1036 | PARAVIRT_ADJUST_EXCEPTION_FRAME | |
b1cccb1b JB |
1037 | pushq_cfi $-1 /* ORIG_RAX: no syscall to restart */ |
1038 | subq $ORIG_RAX-R15, %rsp | |
1039 | CFI_ADJUST_CFA_OFFSET ORIG_RAX-R15 | |
b8b1d08b AH |
1040 | call save_paranoid |
1041 | TRACE_IRQS_OFF | |
1042 | movq %rsp,%rdi /* pt_regs pointer */ | |
1043 | xorl %esi,%esi /* no error code */ | |
322648d1 | 1044 | call \do_sym |
b8b1d08b AH |
1045 | jmp paranoid_exit /* %ebx: no swapgs flag */ |
1046 | CFI_ENDPROC | |
ddeb8f21 | 1047 | END(\sym) |
322648d1 | 1048 | .endm |
b8b1d08b | 1049 | |
c15a5958 | 1050 | #define INIT_TSS_IST(x) PER_CPU_VAR(init_tss) + (TSS_ist + ((x) - 1) * 8) |
322648d1 | 1051 | .macro paranoidzeroentry_ist sym do_sym ist |
ddeb8f21 | 1052 | ENTRY(\sym) |
9f1e87ea | 1053 | INTR_FRAME |
b8b1d08b | 1054 | PARAVIRT_ADJUST_EXCEPTION_FRAME |
b1cccb1b JB |
1055 | pushq_cfi $-1 /* ORIG_RAX: no syscall to restart */ |
1056 | subq $ORIG_RAX-R15, %rsp | |
1057 | CFI_ADJUST_CFA_OFFSET ORIG_RAX-R15 | |
b8b1d08b AH |
1058 | call save_paranoid |
1059 | TRACE_IRQS_OFF | |
1060 | movq %rsp,%rdi /* pt_regs pointer */ | |
1061 | xorl %esi,%esi /* no error code */ | |
c15a5958 | 1062 | subq $EXCEPTION_STKSZ, INIT_TSS_IST(\ist) |
322648d1 | 1063 | call \do_sym |
c15a5958 | 1064 | addq $EXCEPTION_STKSZ, INIT_TSS_IST(\ist) |
b8b1d08b AH |
1065 | jmp paranoid_exit /* %ebx: no swapgs flag */ |
1066 | CFI_ENDPROC | |
ddeb8f21 | 1067 | END(\sym) |
322648d1 | 1068 | .endm |
b8b1d08b | 1069 | |
ddeb8f21 | 1070 | .macro errorentry sym do_sym |
322648d1 | 1071 | ENTRY(\sym) |
7effaa88 | 1072 | XCPT_FRAME |
fab58420 | 1073 | PARAVIRT_ADJUST_EXCEPTION_FRAME |
b1cccb1b JB |
1074 | subq $ORIG_RAX-R15, %rsp |
1075 | CFI_ADJUST_CFA_OFFSET ORIG_RAX-R15 | |
d99015b1 | 1076 | call error_entry |
dcd072e2 | 1077 | DEFAULT_FRAME 0 |
d99015b1 AH |
1078 | movq %rsp,%rdi /* pt_regs pointer */ |
1079 | movq ORIG_RAX(%rsp),%rsi /* get error code */ | |
1080 | movq $-1,ORIG_RAX(%rsp) /* no syscall to restart */ | |
322648d1 | 1081 | call \do_sym |
d99015b1 | 1082 | jmp error_exit /* %ebx: no swapgs flag */ |
7effaa88 | 1083 | CFI_ENDPROC |
322648d1 | 1084 | END(\sym) |
322648d1 | 1085 | .endm |
1da177e4 LT |
1086 | |
1087 | /* error code is on the stack already */ | |
ddeb8f21 | 1088 | .macro paranoiderrorentry sym do_sym |
322648d1 | 1089 | ENTRY(\sym) |
b8b1d08b AH |
1090 | XCPT_FRAME |
1091 | PARAVIRT_ADJUST_EXCEPTION_FRAME | |
b1cccb1b JB |
1092 | subq $ORIG_RAX-R15, %rsp |
1093 | CFI_ADJUST_CFA_OFFSET ORIG_RAX-R15 | |
e2f6bc25 AH |
1094 | call save_paranoid |
1095 | DEFAULT_FRAME 0 | |
7e61a793 | 1096 | TRACE_IRQS_OFF |
b8b1d08b AH |
1097 | movq %rsp,%rdi /* pt_regs pointer */ |
1098 | movq ORIG_RAX(%rsp),%rsi /* get error code */ | |
1099 | movq $-1,ORIG_RAX(%rsp) /* no syscall to restart */ | |
322648d1 | 1100 | call \do_sym |
b8b1d08b AH |
1101 | jmp paranoid_exit /* %ebx: no swapgs flag */ |
1102 | CFI_ENDPROC | |
322648d1 | 1103 | END(\sym) |
322648d1 AH |
1104 | .endm |
1105 | ||
1106 | zeroentry divide_error do_divide_error | |
322648d1 AH |
1107 | zeroentry overflow do_overflow |
1108 | zeroentry bounds do_bounds | |
1109 | zeroentry invalid_op do_invalid_op | |
1110 | zeroentry device_not_available do_device_not_available | |
ddeb8f21 | 1111 | paranoiderrorentry double_fault do_double_fault |
322648d1 AH |
1112 | zeroentry coprocessor_segment_overrun do_coprocessor_segment_overrun |
1113 | errorentry invalid_TSS do_invalid_TSS | |
1114 | errorentry segment_not_present do_segment_not_present | |
322648d1 AH |
1115 | zeroentry spurious_interrupt_bug do_spurious_interrupt_bug |
1116 | zeroentry coprocessor_error do_coprocessor_error | |
1117 | errorentry alignment_check do_alignment_check | |
322648d1 | 1118 | zeroentry simd_coprocessor_error do_simd_coprocessor_error |
2601e64d | 1119 | |
9f1e87ea CG |
1120 | /* Reload gs selector with exception handling */ |
1121 | /* edi: new selector */ | |
9f9d489a | 1122 | ENTRY(native_load_gs_index) |
7effaa88 | 1123 | CFI_STARTPROC |
df5d1874 | 1124 | pushfq_cfi |
b8aa287f | 1125 | DISABLE_INTERRUPTS(CLBR_ANY & ~CLBR_RDI) |
9f1e87ea | 1126 | SWAPGS |
0bd7b798 | 1127 | gs_change: |
9f1e87ea | 1128 | movl %edi,%gs |
1da177e4 | 1129 | 2: mfence /* workaround */ |
72fe4858 | 1130 | SWAPGS |
df5d1874 | 1131 | popfq_cfi |
9f1e87ea | 1132 | ret |
7effaa88 | 1133 | CFI_ENDPROC |
6efdcfaf | 1134 | END(native_load_gs_index) |
0bd7b798 | 1135 | |
9f1e87ea CG |
1136 | .section __ex_table,"a" |
1137 | .align 8 | |
1138 | .quad gs_change,bad_gs | |
1139 | .previous | |
1140 | .section .fixup,"ax" | |
1da177e4 | 1141 | /* running with kernelgs */ |
0bd7b798 | 1142 | bad_gs: |
72fe4858 | 1143 | SWAPGS /* switch back to user gs */ |
1da177e4 | 1144 | xorl %eax,%eax |
9f1e87ea CG |
1145 | movl %eax,%gs |
1146 | jmp 2b | |
1147 | .previous | |
0bd7b798 | 1148 | |
3bd95dfb | 1149 | ENTRY(kernel_thread_helper) |
c05991ed AK |
1150 | pushq $0 # fake return address |
1151 | CFI_STARTPROC | |
1da177e4 LT |
1152 | /* |
1153 | * Here we are in the child and the registers are set as they were | |
1154 | * at kernel_thread() invocation in the parent. | |
1155 | */ | |
3bd95dfb | 1156 | call *%rsi |
1da177e4 | 1157 | # exit |
1c5b5cfd | 1158 | mov %eax, %edi |
1da177e4 | 1159 | call do_exit |
5f5db591 | 1160 | ud2 # padding for call trace |
c05991ed | 1161 | CFI_ENDPROC |
3bd95dfb | 1162 | END(kernel_thread_helper) |
1da177e4 LT |
1163 | |
1164 | /* | |
1165 | * execve(). This function needs to use IRET, not SYSRET, to set up all state properly. | |
1166 | * | |
1167 | * C extern interface: | |
c7887325 | 1168 | * extern long execve(const char *name, char **argv, char **envp) |
1da177e4 LT |
1169 | * |
1170 | * asm input arguments: | |
1171 | * rdi: name, rsi: argv, rdx: envp | |
1172 | * | |
1173 | * We want to fallback into: | |
c7887325 | 1174 | * extern long sys_execve(const char *name, char **argv,char **envp, struct pt_regs *regs) |
1da177e4 LT |
1175 | * |
1176 | * do_sys_execve asm fallback arguments: | |
5d119b2c | 1177 | * rdi: name, rsi: argv, rdx: envp, rcx: fake frame on the stack |
1da177e4 | 1178 | */ |
3db03b4a | 1179 | ENTRY(kernel_execve) |
1da177e4 LT |
1180 | CFI_STARTPROC |
1181 | FAKE_STACK_FRAME $0 | |
0bd7b798 | 1182 | SAVE_ALL |
5d119b2c | 1183 | movq %rsp,%rcx |
1da177e4 | 1184 | call sys_execve |
0bd7b798 | 1185 | movq %rax, RAX(%rsp) |
1da177e4 LT |
1186 | RESTORE_REST |
1187 | testq %rax,%rax | |
1188 | je int_ret_from_sys_call | |
1189 | RESTORE_ARGS | |
1190 | UNFAKE_STACK_FRAME | |
1191 | ret | |
1192 | CFI_ENDPROC | |
6efdcfaf | 1193 | END(kernel_execve) |
1da177e4 | 1194 | |
2699500b | 1195 | /* Call softirq on interrupt stack. Interrupts are off. */ |
ed6b676c | 1196 | ENTRY(call_softirq) |
7effaa88 | 1197 | CFI_STARTPROC |
df5d1874 | 1198 | pushq_cfi %rbp |
2699500b AK |
1199 | CFI_REL_OFFSET rbp,0 |
1200 | mov %rsp,%rbp | |
1201 | CFI_DEF_CFA_REGISTER rbp | |
56895530 | 1202 | incl PER_CPU_VAR(irq_count) |
26f80bd6 | 1203 | cmove PER_CPU_VAR(irq_stack_ptr),%rsp |
2699500b | 1204 | push %rbp # backlink for old unwinder |
ed6b676c | 1205 | call __do_softirq |
2699500b | 1206 | leaveq |
df5d1874 | 1207 | CFI_RESTORE rbp |
7effaa88 | 1208 | CFI_DEF_CFA_REGISTER rsp |
2699500b | 1209 | CFI_ADJUST_CFA_OFFSET -8 |
56895530 | 1210 | decl PER_CPU_VAR(irq_count) |
ed6b676c | 1211 | ret |
7effaa88 | 1212 | CFI_ENDPROC |
6efdcfaf | 1213 | END(call_softirq) |
75154f40 | 1214 | |
3d75e1b8 | 1215 | #ifdef CONFIG_XEN |
322648d1 | 1216 | zeroentry xen_hypervisor_callback xen_do_hypervisor_callback |
3d75e1b8 JF |
1217 | |
1218 | /* | |
9f1e87ea CG |
1219 | * A note on the "critical region" in our callback handler. |
1220 | * We want to avoid stacking callback handlers due to events occurring | |
1221 | * during handling of the last event. To do this, we keep events disabled | |
1222 | * until we've done all processing. HOWEVER, we must enable events before | |
1223 | * popping the stack frame (can't be done atomically) and so it would still | |
1224 | * be possible to get enough handler activations to overflow the stack. | |
1225 | * Although unlikely, bugs of that kind are hard to track down, so we'd | |
1226 | * like to avoid the possibility. | |
1227 | * So, on entry to the handler we detect whether we interrupted an | |
1228 | * existing activation in its critical region -- if so, we pop the current | |
1229 | * activation and restart the handler using the previous one. | |
1230 | */ | |
3d75e1b8 JF |
1231 | ENTRY(xen_do_hypervisor_callback) # do_hypervisor_callback(struct *pt_regs) |
1232 | CFI_STARTPROC | |
9f1e87ea CG |
1233 | /* |
1234 | * Since we don't modify %rdi, evtchn_do_upall(struct *pt_regs) will | |
1235 | * see the correct pointer to the pt_regs | |
1236 | */ | |
3d75e1b8 JF |
1237 | movq %rdi, %rsp # we don't return, adjust the stack frame |
1238 | CFI_ENDPROC | |
dcd072e2 | 1239 | DEFAULT_FRAME |
56895530 | 1240 | 11: incl PER_CPU_VAR(irq_count) |
3d75e1b8 JF |
1241 | movq %rsp,%rbp |
1242 | CFI_DEF_CFA_REGISTER rbp | |
26f80bd6 | 1243 | cmovzq PER_CPU_VAR(irq_stack_ptr),%rsp |
3d75e1b8 JF |
1244 | pushq %rbp # backlink for old unwinder |
1245 | call xen_evtchn_do_upcall | |
1246 | popq %rsp | |
1247 | CFI_DEF_CFA_REGISTER rsp | |
56895530 | 1248 | decl PER_CPU_VAR(irq_count) |
3d75e1b8 JF |
1249 | jmp error_exit |
1250 | CFI_ENDPROC | |
1251 | END(do_hypervisor_callback) | |
1252 | ||
1253 | /* | |
9f1e87ea CG |
1254 | * Hypervisor uses this for application faults while it executes. |
1255 | * We get here for two reasons: | |
1256 | * 1. Fault while reloading DS, ES, FS or GS | |
1257 | * 2. Fault while executing IRET | |
1258 | * Category 1 we do not need to fix up as Xen has already reloaded all segment | |
1259 | * registers that could be reloaded and zeroed the others. | |
1260 | * Category 2 we fix up by killing the current process. We cannot use the | |
1261 | * normal Linux return path in this case because if we use the IRET hypercall | |
1262 | * to pop the stack frame we end up in an infinite loop of failsafe callbacks. | |
1263 | * We distinguish between categories by comparing each saved segment register | |
1264 | * with its current contents: any discrepancy means we in category 1. | |
1265 | */ | |
3d75e1b8 | 1266 | ENTRY(xen_failsafe_callback) |
dcd072e2 AH |
1267 | INTR_FRAME 1 (6*8) |
1268 | /*CFI_REL_OFFSET gs,GS*/ | |
1269 | /*CFI_REL_OFFSET fs,FS*/ | |
1270 | /*CFI_REL_OFFSET es,ES*/ | |
1271 | /*CFI_REL_OFFSET ds,DS*/ | |
1272 | CFI_REL_OFFSET r11,8 | |
1273 | CFI_REL_OFFSET rcx,0 | |
3d75e1b8 JF |
1274 | movw %ds,%cx |
1275 | cmpw %cx,0x10(%rsp) | |
1276 | CFI_REMEMBER_STATE | |
1277 | jne 1f | |
1278 | movw %es,%cx | |
1279 | cmpw %cx,0x18(%rsp) | |
1280 | jne 1f | |
1281 | movw %fs,%cx | |
1282 | cmpw %cx,0x20(%rsp) | |
1283 | jne 1f | |
1284 | movw %gs,%cx | |
1285 | cmpw %cx,0x28(%rsp) | |
1286 | jne 1f | |
1287 | /* All segments match their saved values => Category 2 (Bad IRET). */ | |
1288 | movq (%rsp),%rcx | |
1289 | CFI_RESTORE rcx | |
1290 | movq 8(%rsp),%r11 | |
1291 | CFI_RESTORE r11 | |
1292 | addq $0x30,%rsp | |
1293 | CFI_ADJUST_CFA_OFFSET -0x30 | |
14ae22ba IM |
1294 | pushq_cfi $0 /* RIP */ |
1295 | pushq_cfi %r11 | |
1296 | pushq_cfi %rcx | |
4a5c3e77 | 1297 | jmp general_protection |
3d75e1b8 JF |
1298 | CFI_RESTORE_STATE |
1299 | 1: /* Segment mismatch => Category 1 (Bad segment). Retry the IRET. */ | |
1300 | movq (%rsp),%rcx | |
1301 | CFI_RESTORE rcx | |
1302 | movq 8(%rsp),%r11 | |
1303 | CFI_RESTORE r11 | |
1304 | addq $0x30,%rsp | |
1305 | CFI_ADJUST_CFA_OFFSET -0x30 | |
14ae22ba | 1306 | pushq_cfi $0 |
3d75e1b8 JF |
1307 | SAVE_ALL |
1308 | jmp error_exit | |
1309 | CFI_ENDPROC | |
3d75e1b8 JF |
1310 | END(xen_failsafe_callback) |
1311 | ||
38e20b07 SY |
1312 | apicinterrupt XEN_HVM_EVTCHN_CALLBACK \ |
1313 | xen_hvm_callback_vector xen_evtchn_do_upcall | |
1314 | ||
3d75e1b8 | 1315 | #endif /* CONFIG_XEN */ |
ddeb8f21 AH |
1316 | |
1317 | /* | |
1318 | * Some functions should be protected against kprobes | |
1319 | */ | |
1320 | .pushsection .kprobes.text, "ax" | |
1321 | ||
1322 | paranoidzeroentry_ist debug do_debug DEBUG_STACK | |
1323 | paranoidzeroentry_ist int3 do_int3 DEBUG_STACK | |
1324 | paranoiderrorentry stack_segment do_stack_segment | |
6cac5a92 JF |
1325 | #ifdef CONFIG_XEN |
1326 | zeroentry xen_debug do_debug | |
1327 | zeroentry xen_int3 do_int3 | |
1328 | errorentry xen_stack_segment do_stack_segment | |
1329 | #endif | |
ddeb8f21 AH |
1330 | errorentry general_protection do_general_protection |
1331 | errorentry page_fault do_page_fault | |
631bc487 GN |
1332 | #ifdef CONFIG_KVM_GUEST |
1333 | errorentry async_page_fault do_async_page_fault | |
1334 | #endif | |
ddeb8f21 | 1335 | #ifdef CONFIG_X86_MCE |
5d727926 | 1336 | paranoidzeroentry machine_check *machine_check_vector(%rip) |
ddeb8f21 AH |
1337 | #endif |
1338 | ||
1339 | /* | |
9f1e87ea CG |
1340 | * "Paranoid" exit path from exception stack. |
1341 | * Paranoid because this is used by NMIs and cannot take | |
ddeb8f21 AH |
1342 | * any kernel state for granted. |
1343 | * We don't do kernel preemption checks here, because only | |
1344 | * NMI should be common and it does not enable IRQs and | |
1345 | * cannot get reschedule ticks. | |
1346 | * | |
1347 | * "trace" is 0 for the NMI handler only, because irq-tracing | |
1348 | * is fundamentally NMI-unsafe. (we cannot change the soft and | |
1349 | * hard flags at once, atomically) | |
1350 | */ | |
1351 | ||
1352 | /* ebx: no swapgs flag */ | |
1353 | ENTRY(paranoid_exit) | |
1f130a78 | 1354 | DEFAULT_FRAME |
ddeb8f21 AH |
1355 | DISABLE_INTERRUPTS(CLBR_NONE) |
1356 | TRACE_IRQS_OFF | |
1357 | testl %ebx,%ebx /* swapgs needed? */ | |
1358 | jnz paranoid_restore | |
1359 | testl $3,CS(%rsp) | |
1360 | jnz paranoid_userspace | |
1361 | paranoid_swapgs: | |
1362 | TRACE_IRQS_IRETQ 0 | |
1363 | SWAPGS_UNSAFE_STACK | |
0300e7f1 SR |
1364 | RESTORE_ALL 8 |
1365 | jmp irq_return | |
ddeb8f21 | 1366 | paranoid_restore: |
0300e7f1 | 1367 | TRACE_IRQS_IRETQ 0 |
ddeb8f21 AH |
1368 | RESTORE_ALL 8 |
1369 | jmp irq_return | |
1370 | paranoid_userspace: | |
1371 | GET_THREAD_INFO(%rcx) | |
1372 | movl TI_flags(%rcx),%ebx | |
1373 | andl $_TIF_WORK_MASK,%ebx | |
1374 | jz paranoid_swapgs | |
1375 | movq %rsp,%rdi /* &pt_regs */ | |
1376 | call sync_regs | |
1377 | movq %rax,%rsp /* switch stack for scheduling */ | |
1378 | testl $_TIF_NEED_RESCHED,%ebx | |
1379 | jnz paranoid_schedule | |
1380 | movl %ebx,%edx /* arg3: thread flags */ | |
1381 | TRACE_IRQS_ON | |
1382 | ENABLE_INTERRUPTS(CLBR_NONE) | |
1383 | xorl %esi,%esi /* arg2: oldset */ | |
1384 | movq %rsp,%rdi /* arg1: &pt_regs */ | |
1385 | call do_notify_resume | |
1386 | DISABLE_INTERRUPTS(CLBR_NONE) | |
1387 | TRACE_IRQS_OFF | |
1388 | jmp paranoid_userspace | |
1389 | paranoid_schedule: | |
1390 | TRACE_IRQS_ON | |
1391 | ENABLE_INTERRUPTS(CLBR_ANY) | |
1392 | call schedule | |
1393 | DISABLE_INTERRUPTS(CLBR_ANY) | |
1394 | TRACE_IRQS_OFF | |
1395 | jmp paranoid_userspace | |
1396 | CFI_ENDPROC | |
1397 | END(paranoid_exit) | |
1398 | ||
1399 | /* | |
1400 | * Exception entry point. This expects an error code/orig_rax on the stack. | |
1401 | * returns in "no swapgs flag" in %ebx. | |
1402 | */ | |
1403 | ENTRY(error_entry) | |
1404 | XCPT_FRAME | |
1405 | CFI_ADJUST_CFA_OFFSET 15*8 | |
1406 | /* oldrax contains error code */ | |
1407 | cld | |
1408 | movq_cfi rdi, RDI+8 | |
1409 | movq_cfi rsi, RSI+8 | |
1410 | movq_cfi rdx, RDX+8 | |
1411 | movq_cfi rcx, RCX+8 | |
1412 | movq_cfi rax, RAX+8 | |
1413 | movq_cfi r8, R8+8 | |
1414 | movq_cfi r9, R9+8 | |
1415 | movq_cfi r10, R10+8 | |
1416 | movq_cfi r11, R11+8 | |
1417 | movq_cfi rbx, RBX+8 | |
1418 | movq_cfi rbp, RBP+8 | |
1419 | movq_cfi r12, R12+8 | |
1420 | movq_cfi r13, R13+8 | |
1421 | movq_cfi r14, R14+8 | |
1422 | movq_cfi r15, R15+8 | |
1423 | xorl %ebx,%ebx | |
1424 | testl $3,CS+8(%rsp) | |
1425 | je error_kernelspace | |
1426 | error_swapgs: | |
1427 | SWAPGS | |
1428 | error_sti: | |
1429 | TRACE_IRQS_OFF | |
1430 | ret | |
ddeb8f21 AH |
1431 | |
1432 | /* | |
1433 | * There are two places in the kernel that can potentially fault with | |
1434 | * usergs. Handle them here. The exception handlers after iret run with | |
1435 | * kernel gs again, so don't set the user space flag. B stepping K8s | |
1436 | * sometimes report an truncated RIP for IRET exceptions returning to | |
1437 | * compat mode. Check for these here too. | |
1438 | */ | |
1439 | error_kernelspace: | |
1440 | incl %ebx | |
1441 | leaq irq_return(%rip),%rcx | |
1442 | cmpq %rcx,RIP+8(%rsp) | |
1443 | je error_swapgs | |
ae24ffe5 BG |
1444 | movl %ecx,%eax /* zero extend */ |
1445 | cmpq %rax,RIP+8(%rsp) | |
1446 | je bstep_iret | |
ddeb8f21 | 1447 | cmpq $gs_change,RIP+8(%rsp) |
9f1e87ea | 1448 | je error_swapgs |
ddeb8f21 | 1449 | jmp error_sti |
ae24ffe5 BG |
1450 | |
1451 | bstep_iret: | |
1452 | /* Fix truncated RIP */ | |
1453 | movq %rcx,RIP+8(%rsp) | |
97829de5 | 1454 | jmp error_swapgs |
e6b04b6b | 1455 | CFI_ENDPROC |
ddeb8f21 AH |
1456 | END(error_entry) |
1457 | ||
1458 | ||
1459 | /* ebx: no swapgs flag (1: don't need swapgs, 0: need it) */ | |
1460 | ENTRY(error_exit) | |
1461 | DEFAULT_FRAME | |
1462 | movl %ebx,%eax | |
1463 | RESTORE_REST | |
1464 | DISABLE_INTERRUPTS(CLBR_NONE) | |
1465 | TRACE_IRQS_OFF | |
1466 | GET_THREAD_INFO(%rcx) | |
1467 | testl %eax,%eax | |
1468 | jne retint_kernel | |
1469 | LOCKDEP_SYS_EXIT_IRQ | |
1470 | movl TI_flags(%rcx),%edx | |
1471 | movl $_TIF_WORK_MASK,%edi | |
1472 | andl %edi,%edx | |
1473 | jnz retint_careful | |
1474 | jmp retint_swapgs | |
1475 | CFI_ENDPROC | |
1476 | END(error_exit) | |
1477 | ||
1478 | ||
1479 | /* runs on exception stack */ | |
1480 | ENTRY(nmi) | |
1481 | INTR_FRAME | |
1482 | PARAVIRT_ADJUST_EXCEPTION_FRAME | |
1483 | pushq_cfi $-1 | |
b1cccb1b JB |
1484 | subq $ORIG_RAX-R15, %rsp |
1485 | CFI_ADJUST_CFA_OFFSET ORIG_RAX-R15 | |
ddeb8f21 AH |
1486 | call save_paranoid |
1487 | DEFAULT_FRAME 0 | |
1488 | /* paranoidentry do_nmi, 0; without TRACE_IRQS_OFF */ | |
1489 | movq %rsp,%rdi | |
1490 | movq $-1,%rsi | |
1491 | call do_nmi | |
1492 | #ifdef CONFIG_TRACE_IRQFLAGS | |
1493 | /* paranoidexit; without TRACE_IRQS_OFF */ | |
1494 | /* ebx: no swapgs flag */ | |
1495 | DISABLE_INTERRUPTS(CLBR_NONE) | |
1496 | testl %ebx,%ebx /* swapgs needed? */ | |
1497 | jnz nmi_restore | |
1498 | testl $3,CS(%rsp) | |
1499 | jnz nmi_userspace | |
1500 | nmi_swapgs: | |
1501 | SWAPGS_UNSAFE_STACK | |
1502 | nmi_restore: | |
1503 | RESTORE_ALL 8 | |
1504 | jmp irq_return | |
1505 | nmi_userspace: | |
1506 | GET_THREAD_INFO(%rcx) | |
1507 | movl TI_flags(%rcx),%ebx | |
1508 | andl $_TIF_WORK_MASK,%ebx | |
1509 | jz nmi_swapgs | |
1510 | movq %rsp,%rdi /* &pt_regs */ | |
1511 | call sync_regs | |
1512 | movq %rax,%rsp /* switch stack for scheduling */ | |
1513 | testl $_TIF_NEED_RESCHED,%ebx | |
1514 | jnz nmi_schedule | |
1515 | movl %ebx,%edx /* arg3: thread flags */ | |
1516 | ENABLE_INTERRUPTS(CLBR_NONE) | |
1517 | xorl %esi,%esi /* arg2: oldset */ | |
1518 | movq %rsp,%rdi /* arg1: &pt_regs */ | |
1519 | call do_notify_resume | |
1520 | DISABLE_INTERRUPTS(CLBR_NONE) | |
1521 | jmp nmi_userspace | |
1522 | nmi_schedule: | |
1523 | ENABLE_INTERRUPTS(CLBR_ANY) | |
1524 | call schedule | |
1525 | DISABLE_INTERRUPTS(CLBR_ANY) | |
1526 | jmp nmi_userspace | |
1527 | CFI_ENDPROC | |
1528 | #else | |
1529 | jmp paranoid_exit | |
9f1e87ea | 1530 | CFI_ENDPROC |
ddeb8f21 AH |
1531 | #endif |
1532 | END(nmi) | |
1533 | ||
1534 | ENTRY(ignore_sysret) | |
1535 | CFI_STARTPROC | |
1536 | mov $-ENOSYS,%eax | |
1537 | sysret | |
1538 | CFI_ENDPROC | |
1539 | END(ignore_sysret) | |
1540 | ||
1541 | /* | |
1542 | * End of kprobes section | |
1543 | */ | |
1544 | .popsection |