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Commit | Line | Data |
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3f33ab1c MH |
1 | /* |
2 | * Kernel Probes Jump Optimization (Optprobes) | |
3 | * | |
4 | * This program is free software; you can redistribute it and/or modify | |
5 | * it under the terms of the GNU General Public License as published by | |
6 | * the Free Software Foundation; either version 2 of the License, or | |
7 | * (at your option) any later version. | |
8 | * | |
9 | * This program is distributed in the hope that it will be useful, | |
10 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
11 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
12 | * GNU General Public License for more details. | |
13 | * | |
14 | * You should have received a copy of the GNU General Public License | |
15 | * along with this program; if not, write to the Free Software | |
16 | * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. | |
17 | * | |
18 | * Copyright (C) IBM Corporation, 2002, 2004 | |
19 | * Copyright (C) Hitachi Ltd., 2012 | |
20 | */ | |
21 | #include <linux/kprobes.h> | |
22 | #include <linux/ptrace.h> | |
23 | #include <linux/string.h> | |
24 | #include <linux/slab.h> | |
25 | #include <linux/hardirq.h> | |
26 | #include <linux/preempt.h> | |
744c193e | 27 | #include <linux/extable.h> |
3f33ab1c MH |
28 | #include <linux/kdebug.h> |
29 | #include <linux/kallsyms.h> | |
30 | #include <linux/ftrace.h> | |
c207aee4 | 31 | #include <linux/frame.h> |
3f33ab1c | 32 | |
35de5b06 | 33 | #include <asm/text-patching.h> |
3f33ab1c MH |
34 | #include <asm/cacheflush.h> |
35 | #include <asm/desc.h> | |
36 | #include <asm/pgtable.h> | |
7c0f6ba6 | 37 | #include <linux/uaccess.h> |
3f33ab1c MH |
38 | #include <asm/alternative.h> |
39 | #include <asm/insn.h> | |
40 | #include <asm/debugreg.h> | |
e6ccbff0 | 41 | #include <asm/set_memory.h> |
d9f5f32a | 42 | #include <asm/sections.h> |
c86a32c0 | 43 | #include <asm/nospec-branch.h> |
3f33ab1c | 44 | |
f684199f | 45 | #include "common.h" |
3f33ab1c MH |
46 | |
47 | unsigned long __recover_optprobed_insn(kprobe_opcode_t *buf, unsigned long addr) | |
48 | { | |
49 | struct optimized_kprobe *op; | |
50 | struct kprobe *kp; | |
51 | long offs; | |
52 | int i; | |
53 | ||
54 | for (i = 0; i < RELATIVEJUMP_SIZE; i++) { | |
55 | kp = get_kprobe((void *)addr - i); | |
56 | /* This function only handles jump-optimized kprobe */ | |
57 | if (kp && kprobe_optimized(kp)) { | |
58 | op = container_of(kp, struct optimized_kprobe, kp); | |
59 | /* If op->list is not empty, op is under optimizing */ | |
60 | if (list_empty(&op->list)) | |
61 | goto found; | |
62 | } | |
63 | } | |
64 | ||
65 | return addr; | |
66 | found: | |
67 | /* | |
68 | * If the kprobe can be optimized, original bytes which can be | |
69 | * overwritten by jump destination address. In this case, original | |
70 | * bytes must be recovered from op->optinsn.copied_insn buffer. | |
71 | */ | |
ea1e34fc MH |
72 | if (probe_kernel_read(buf, (void *)addr, |
73 | MAX_INSN_SIZE * sizeof(kprobe_opcode_t))) | |
74 | return 0UL; | |
75 | ||
3f33ab1c MH |
76 | if (addr == (unsigned long)kp->addr) { |
77 | buf[0] = kp->opcode; | |
78 | memcpy(buf + 1, op->optinsn.copied_insn, RELATIVE_ADDR_SIZE); | |
79 | } else { | |
80 | offs = addr - (unsigned long)kp->addr - 1; | |
81 | memcpy(buf, op->optinsn.copied_insn + offs, RELATIVE_ADDR_SIZE - offs); | |
82 | } | |
83 | ||
84 | return (unsigned long)buf; | |
85 | } | |
86 | ||
87 | /* Insert a move instruction which sets a pointer to eax/rdi (1st arg). */ | |
7ec8a97a | 88 | static void synthesize_set_arg1(kprobe_opcode_t *addr, unsigned long val) |
3f33ab1c MH |
89 | { |
90 | #ifdef CONFIG_X86_64 | |
91 | *addr++ = 0x48; | |
92 | *addr++ = 0xbf; | |
93 | #else | |
94 | *addr++ = 0xb8; | |
95 | #endif | |
96 | *(unsigned long *)addr = val; | |
97 | } | |
98 | ||
04bb591c | 99 | asm ( |
c207aee4 | 100 | "optprobe_template_func:\n" |
3f33ab1c MH |
101 | ".global optprobe_template_entry\n" |
102 | "optprobe_template_entry:\n" | |
103 | #ifdef CONFIG_X86_64 | |
104 | /* We don't bother saving the ss register */ | |
105 | " pushq %rsp\n" | |
106 | " pushfq\n" | |
107 | SAVE_REGS_STRING | |
108 | " movq %rsp, %rsi\n" | |
109 | ".global optprobe_template_val\n" | |
110 | "optprobe_template_val:\n" | |
111 | ASM_NOP5 | |
112 | ASM_NOP5 | |
113 | ".global optprobe_template_call\n" | |
114 | "optprobe_template_call:\n" | |
115 | ASM_NOP5 | |
116 | /* Move flags to rsp */ | |
117 | " movq 144(%rsp), %rdx\n" | |
118 | " movq %rdx, 152(%rsp)\n" | |
119 | RESTORE_REGS_STRING | |
120 | /* Skip flags entry */ | |
121 | " addq $8, %rsp\n" | |
122 | " popfq\n" | |
123 | #else /* CONFIG_X86_32 */ | |
124 | " pushf\n" | |
125 | SAVE_REGS_STRING | |
126 | " movl %esp, %edx\n" | |
127 | ".global optprobe_template_val\n" | |
128 | "optprobe_template_val:\n" | |
129 | ASM_NOP5 | |
130 | ".global optprobe_template_call\n" | |
131 | "optprobe_template_call:\n" | |
132 | ASM_NOP5 | |
133 | RESTORE_REGS_STRING | |
134 | " addl $4, %esp\n" /* skip cs */ | |
135 | " popf\n" | |
136 | #endif | |
137 | ".global optprobe_template_end\n" | |
c207aee4 JP |
138 | "optprobe_template_end:\n" |
139 | ".type optprobe_template_func, @function\n" | |
140 | ".size optprobe_template_func, .-optprobe_template_func\n"); | |
141 | ||
142 | void optprobe_template_func(void); | |
143 | STACK_FRAME_NON_STANDARD(optprobe_template_func); | |
4d7224e8 MH |
144 | NOKPROBE_SYMBOL(optprobe_template_func); |
145 | NOKPROBE_SYMBOL(optprobe_template_entry); | |
146 | NOKPROBE_SYMBOL(optprobe_template_val); | |
147 | NOKPROBE_SYMBOL(optprobe_template_call); | |
148 | NOKPROBE_SYMBOL(optprobe_template_end); | |
3f33ab1c MH |
149 | |
150 | #define TMPL_MOVE_IDX \ | |
a8976fc8 | 151 | ((long)optprobe_template_val - (long)optprobe_template_entry) |
3f33ab1c | 152 | #define TMPL_CALL_IDX \ |
a8976fc8 | 153 | ((long)optprobe_template_call - (long)optprobe_template_entry) |
3f33ab1c | 154 | #define TMPL_END_IDX \ |
a8976fc8 | 155 | ((long)optprobe_template_end - (long)optprobe_template_entry) |
3f33ab1c MH |
156 | |
157 | #define INT3_SIZE sizeof(kprobe_opcode_t) | |
158 | ||
159 | /* Optimized kprobe call back function: called from optinsn */ | |
9326638c MH |
160 | static void |
161 | optimized_callback(struct optimized_kprobe *op, struct pt_regs *regs) | |
3f33ab1c | 162 | { |
3f33ab1c MH |
163 | /* This is possible if op is under delayed unoptimizing */ |
164 | if (kprobe_disabled(&op->kp)) | |
165 | return; | |
166 | ||
9a09f261 | 167 | preempt_disable(); |
3f33ab1c MH |
168 | if (kprobe_running()) { |
169 | kprobes_inc_nmissed_count(&op->kp); | |
170 | } else { | |
cd52edad | 171 | struct kprobe_ctlblk *kcb = get_kprobe_ctlblk(); |
3f33ab1c MH |
172 | /* Save skipped registers */ |
173 | #ifdef CONFIG_X86_64 | |
174 | regs->cs = __KERNEL_CS; | |
175 | #else | |
176 | regs->cs = __KERNEL_CS | get_kernel_rpl(); | |
177 | regs->gs = 0; | |
178 | #endif | |
179 | regs->ip = (unsigned long)op->kp.addr + INT3_SIZE; | |
180 | regs->orig_ax = ~0UL; | |
181 | ||
182 | __this_cpu_write(current_kprobe, &op->kp); | |
183 | kcb->kprobe_status = KPROBE_HIT_ACTIVE; | |
184 | opt_pre_handler(&op->kp, regs); | |
185 | __this_cpu_write(current_kprobe, NULL); | |
186 | } | |
87208eb1 | 187 | preempt_enable(); |
3f33ab1c | 188 | } |
9326638c | 189 | NOKPROBE_SYMBOL(optimized_callback); |
3f33ab1c | 190 | |
63fef14f | 191 | static int copy_optimized_instructions(u8 *dest, u8 *src, u8 *real) |
3f33ab1c | 192 | { |
a8d11cd0 | 193 | struct insn insn; |
3f33ab1c MH |
194 | int len = 0, ret; |
195 | ||
196 | while (len < RELATIVEJUMP_SIZE) { | |
6fd1ae94 | 197 | ret = __copy_instruction(dest + len, src + len, real + len, &insn); |
a8d11cd0 | 198 | if (!ret || !can_boost(&insn, src + len)) |
3f33ab1c MH |
199 | return -EINVAL; |
200 | len += ret; | |
201 | } | |
202 | /* Check whether the address range is reserved */ | |
203 | if (ftrace_text_reserved(src, src + len - 1) || | |
204 | alternatives_text_reserved(src, src + len - 1) || | |
205 | jump_label_text_reserved(src, src + len - 1)) | |
206 | return -EBUSY; | |
207 | ||
208 | return len; | |
209 | } | |
210 | ||
211 | /* Check whether insn is indirect jump */ | |
c86a32c0 | 212 | static int __insn_is_indirect_jump(struct insn *insn) |
3f33ab1c MH |
213 | { |
214 | return ((insn->opcode.bytes[0] == 0xff && | |
215 | (X86_MODRM_REG(insn->modrm.value) & 6) == 4) || /* Jump */ | |
216 | insn->opcode.bytes[0] == 0xea); /* Segment based jump */ | |
217 | } | |
218 | ||
219 | /* Check whether insn jumps into specified address range */ | |
220 | static int insn_jump_into_range(struct insn *insn, unsigned long start, int len) | |
221 | { | |
222 | unsigned long target = 0; | |
223 | ||
224 | switch (insn->opcode.bytes[0]) { | |
225 | case 0xe0: /* loopne */ | |
226 | case 0xe1: /* loope */ | |
227 | case 0xe2: /* loop */ | |
228 | case 0xe3: /* jcxz */ | |
229 | case 0xe9: /* near relative jump */ | |
230 | case 0xeb: /* short relative jump */ | |
231 | break; | |
232 | case 0x0f: | |
233 | if ((insn->opcode.bytes[1] & 0xf0) == 0x80) /* jcc near */ | |
234 | break; | |
235 | return 0; | |
236 | default: | |
237 | if ((insn->opcode.bytes[0] & 0xf0) == 0x70) /* jcc short */ | |
238 | break; | |
239 | return 0; | |
240 | } | |
241 | target = (unsigned long)insn->next_byte + insn->immediate.value; | |
242 | ||
243 | return (start <= target && target <= start + len); | |
244 | } | |
245 | ||
c86a32c0 MH |
246 | static int insn_is_indirect_jump(struct insn *insn) |
247 | { | |
248 | int ret = __insn_is_indirect_jump(insn); | |
249 | ||
250 | #ifdef CONFIG_RETPOLINE | |
251 | /* | |
252 | * Jump to x86_indirect_thunk_* is treated as an indirect jump. | |
253 | * Note that even with CONFIG_RETPOLINE=y, the kernel compiled with | |
254 | * older gcc may use indirect jump. So we add this check instead of | |
255 | * replace indirect-jump check. | |
256 | */ | |
257 | if (!ret) | |
258 | ret = insn_jump_into_range(insn, | |
259 | (unsigned long)__indirect_thunk_start, | |
260 | (unsigned long)__indirect_thunk_end - | |
261 | (unsigned long)__indirect_thunk_start); | |
262 | #endif | |
263 | return ret; | |
264 | } | |
265 | ||
3f33ab1c | 266 | /* Decode whole function to ensure any instructions don't jump into target */ |
7ec8a97a | 267 | static int can_optimize(unsigned long paddr) |
3f33ab1c MH |
268 | { |
269 | unsigned long addr, size = 0, offset = 0; | |
270 | struct insn insn; | |
271 | kprobe_opcode_t buf[MAX_INSN_SIZE]; | |
272 | ||
273 | /* Lookup symbol including addr */ | |
274 | if (!kallsyms_lookup_size_offset(paddr, &size, &offset)) | |
275 | return 0; | |
276 | ||
277 | /* | |
278 | * Do not optimize in the entry code due to the unstable | |
d9f5f32a | 279 | * stack handling and registers setup. |
3f33ab1c | 280 | */ |
d9f5f32a MH |
281 | if (((paddr >= (unsigned long)__entry_text_start) && |
282 | (paddr < (unsigned long)__entry_text_end)) || | |
283 | ((paddr >= (unsigned long)__irqentry_text_start) && | |
284 | (paddr < (unsigned long)__irqentry_text_end))) | |
3f33ab1c MH |
285 | return 0; |
286 | ||
287 | /* Check there is enough space for a relative jump. */ | |
288 | if (size - offset < RELATIVEJUMP_SIZE) | |
289 | return 0; | |
290 | ||
291 | /* Decode instructions */ | |
292 | addr = paddr - offset; | |
293 | while (addr < paddr - offset + size) { /* Decode until function end */ | |
6ba48ff4 | 294 | unsigned long recovered_insn; |
3f33ab1c MH |
295 | if (search_exception_tables(addr)) |
296 | /* | |
297 | * Since some fixup code will jumps into this function, | |
298 | * we can't optimize kprobe in this function. | |
299 | */ | |
300 | return 0; | |
6ba48ff4 | 301 | recovered_insn = recover_probed_instruction(buf, addr); |
2a6730c8 PM |
302 | if (!recovered_insn) |
303 | return 0; | |
6ba48ff4 | 304 | kernel_insn_init(&insn, (void *)recovered_insn, MAX_INSN_SIZE); |
3f33ab1c MH |
305 | insn_get_length(&insn); |
306 | /* Another subsystem puts a breakpoint */ | |
307 | if (insn.opcode.bytes[0] == BREAKPOINT_INSTRUCTION) | |
308 | return 0; | |
309 | /* Recover address */ | |
310 | insn.kaddr = (void *)addr; | |
311 | insn.next_byte = (void *)(addr + insn.length); | |
312 | /* Check any instructions don't jump into target */ | |
313 | if (insn_is_indirect_jump(&insn) || | |
314 | insn_jump_into_range(&insn, paddr + INT3_SIZE, | |
315 | RELATIVE_ADDR_SIZE)) | |
316 | return 0; | |
317 | addr += insn.length; | |
318 | } | |
319 | ||
320 | return 1; | |
321 | } | |
322 | ||
323 | /* Check optimized_kprobe can actually be optimized. */ | |
7ec8a97a | 324 | int arch_check_optimized_kprobe(struct optimized_kprobe *op) |
3f33ab1c MH |
325 | { |
326 | int i; | |
327 | struct kprobe *p; | |
328 | ||
329 | for (i = 1; i < op->optinsn.size; i++) { | |
330 | p = get_kprobe(op->kp.addr + i); | |
331 | if (p && !kprobe_disabled(p)) | |
332 | return -EEXIST; | |
333 | } | |
334 | ||
335 | return 0; | |
336 | } | |
337 | ||
338 | /* Check the addr is within the optimized instructions. */ | |
7ec8a97a MH |
339 | int arch_within_optimized_kprobe(struct optimized_kprobe *op, |
340 | unsigned long addr) | |
3f33ab1c MH |
341 | { |
342 | return ((unsigned long)op->kp.addr <= addr && | |
343 | (unsigned long)op->kp.addr + op->optinsn.size > addr); | |
344 | } | |
345 | ||
346 | /* Free optimized instruction slot */ | |
7ec8a97a | 347 | static |
3f33ab1c MH |
348 | void __arch_remove_optimized_kprobe(struct optimized_kprobe *op, int dirty) |
349 | { | |
350 | if (op->optinsn.insn) { | |
351 | free_optinsn_slot(op->optinsn.insn, dirty); | |
352 | op->optinsn.insn = NULL; | |
353 | op->optinsn.size = 0; | |
354 | } | |
355 | } | |
356 | ||
7ec8a97a | 357 | void arch_remove_optimized_kprobe(struct optimized_kprobe *op) |
3f33ab1c MH |
358 | { |
359 | __arch_remove_optimized_kprobe(op, 1); | |
360 | } | |
361 | ||
362 | /* | |
363 | * Copy replacing target instructions | |
364 | * Target instructions MUST be relocatable (checked inside) | |
365 | * This is called when new aggr(opt)probe is allocated or reused. | |
366 | */ | |
cbf6ab52 MH |
367 | int arch_prepare_optimized_kprobe(struct optimized_kprobe *op, |
368 | struct kprobe *__unused) | |
3f33ab1c | 369 | { |
63fef14f MH |
370 | u8 *buf = NULL, *slot; |
371 | int ret, len; | |
3f33ab1c MH |
372 | long rel; |
373 | ||
374 | if (!can_optimize((unsigned long)op->kp.addr)) | |
375 | return -EILSEQ; | |
376 | ||
63fef14f MH |
377 | buf = kzalloc(MAX_OPTINSN_SIZE, GFP_KERNEL); |
378 | if (!buf) | |
3f33ab1c MH |
379 | return -ENOMEM; |
380 | ||
63fef14f MH |
381 | op->optinsn.insn = slot = get_optinsn_slot(); |
382 | if (!slot) { | |
383 | ret = -ENOMEM; | |
384 | goto out; | |
385 | } | |
386 | ||
3f33ab1c MH |
387 | /* |
388 | * Verify if the address gap is in 2GB range, because this uses | |
389 | * a relative jump. | |
390 | */ | |
63fef14f | 391 | rel = (long)slot - (long)op->kp.addr + RELATIVEJUMP_SIZE; |
256aae5e | 392 | if (abs(rel) > 0x7fffffff) { |
63fef14f MH |
393 | ret = -ERANGE; |
394 | goto err; | |
256aae5e | 395 | } |
3f33ab1c | 396 | |
63fef14f | 397 | /* Copy arch-dep-instance from template */ |
a8976fc8 | 398 | memcpy(buf, optprobe_template_entry, TMPL_END_IDX); |
3f33ab1c MH |
399 | |
400 | /* Copy instructions into the out-of-line buffer */ | |
63fef14f MH |
401 | ret = copy_optimized_instructions(buf + TMPL_END_IDX, op->kp.addr, |
402 | slot + TMPL_END_IDX); | |
403 | if (ret < 0) | |
404 | goto err; | |
3f33ab1c | 405 | op->optinsn.size = ret; |
63fef14f | 406 | len = TMPL_END_IDX + op->optinsn.size; |
3f33ab1c MH |
407 | |
408 | /* Set probe information */ | |
409 | synthesize_set_arg1(buf + TMPL_MOVE_IDX, (unsigned long)op); | |
410 | ||
411 | /* Set probe function call */ | |
63fef14f MH |
412 | synthesize_relcall(buf + TMPL_CALL_IDX, |
413 | slot + TMPL_CALL_IDX, optimized_callback); | |
3f33ab1c MH |
414 | |
415 | /* Set returning jmp instruction at the tail of out-of-line buffer */ | |
63fef14f | 416 | synthesize_reljump(buf + len, slot + len, |
3f33ab1c | 417 | (u8 *)op->kp.addr + op->optinsn.size); |
63fef14f MH |
418 | len += RELATIVEJUMP_SIZE; |
419 | ||
420 | /* We have to use text_poke for instuction buffer because it is RO */ | |
421 | text_poke(slot, buf, len); | |
422 | ret = 0; | |
423 | out: | |
424 | kfree(buf); | |
425 | return ret; | |
426 | ||
427 | err: | |
428 | __arch_remove_optimized_kprobe(op, 0); | |
429 | goto out; | |
3f33ab1c MH |
430 | } |
431 | ||
3f33ab1c MH |
432 | /* |
433 | * Replace breakpoints (int3) with relative jumps. | |
434 | * Caller must call with locking kprobe_mutex and text_mutex. | |
435 | */ | |
7ec8a97a | 436 | void arch_optimize_kprobes(struct list_head *oplist) |
3f33ab1c MH |
437 | { |
438 | struct optimized_kprobe *op, *tmp; | |
a7b0133e | 439 | u8 insn_buf[RELATIVEJUMP_SIZE]; |
3f33ab1c MH |
440 | |
441 | list_for_each_entry_safe(op, tmp, oplist, list) { | |
a7b0133e MH |
442 | s32 rel = (s32)((long)op->optinsn.insn - |
443 | ((long)op->kp.addr + RELATIVEJUMP_SIZE)); | |
444 | ||
3f33ab1c | 445 | WARN_ON(kprobe_disabled(&op->kp)); |
a7b0133e MH |
446 | |
447 | /* Backup instructions which will be replaced by jump address */ | |
448 | memcpy(op->optinsn.copied_insn, op->kp.addr + INT3_SIZE, | |
449 | RELATIVE_ADDR_SIZE); | |
450 | ||
451 | insn_buf[0] = RELATIVEJUMP_OPCODE; | |
452 | *(s32 *)(&insn_buf[1]) = rel; | |
453 | ||
454 | text_poke_bp(op->kp.addr, insn_buf, RELATIVEJUMP_SIZE, | |
455 | op->optinsn.insn); | |
456 | ||
3f33ab1c | 457 | list_del_init(&op->list); |
3f33ab1c | 458 | } |
3f33ab1c MH |
459 | } |
460 | ||
a7b0133e | 461 | /* Replace a relative jump with a breakpoint (int3). */ |
7ec8a97a | 462 | void arch_unoptimize_kprobe(struct optimized_kprobe *op) |
3f33ab1c | 463 | { |
a7b0133e MH |
464 | u8 insn_buf[RELATIVEJUMP_SIZE]; |
465 | ||
3f33ab1c MH |
466 | /* Set int3 to first byte for kprobes */ |
467 | insn_buf[0] = BREAKPOINT_INSTRUCTION; | |
468 | memcpy(insn_buf + 1, op->optinsn.copied_insn, RELATIVE_ADDR_SIZE); | |
a7b0133e MH |
469 | text_poke_bp(op->kp.addr, insn_buf, RELATIVEJUMP_SIZE, |
470 | op->optinsn.insn); | |
3f33ab1c MH |
471 | } |
472 | ||
473 | /* | |
474 | * Recover original instructions and breakpoints from relative jumps. | |
475 | * Caller must call with locking kprobe_mutex. | |
476 | */ | |
477 | extern void arch_unoptimize_kprobes(struct list_head *oplist, | |
478 | struct list_head *done_list) | |
479 | { | |
480 | struct optimized_kprobe *op, *tmp; | |
3f33ab1c MH |
481 | |
482 | list_for_each_entry_safe(op, tmp, oplist, list) { | |
a7b0133e | 483 | arch_unoptimize_kprobe(op); |
3f33ab1c | 484 | list_move(&op->list, done_list); |
3f33ab1c | 485 | } |
3f33ab1c MH |
486 | } |
487 | ||
9326638c | 488 | int setup_detour_execution(struct kprobe *p, struct pt_regs *regs, int reenter) |
3f33ab1c MH |
489 | { |
490 | struct optimized_kprobe *op; | |
491 | ||
492 | if (p->flags & KPROBE_FLAG_OPTIMIZED) { | |
493 | /* This kprobe is really able to run optimized path. */ | |
494 | op = container_of(p, struct optimized_kprobe, kp); | |
495 | /* Detour through copied instructions */ | |
496 | regs->ip = (unsigned long)op->optinsn.insn + TMPL_END_IDX; | |
497 | if (!reenter) | |
498 | reset_current_kprobe(); | |
499 | preempt_enable_no_resched(); | |
500 | return 1; | |
501 | } | |
502 | return 0; | |
503 | } | |
9326638c | 504 | NOKPROBE_SYMBOL(setup_detour_execution); |