xref: /openbmc/linux/arch/mips/kernel/ptrace.c (revision 0c874100)
1 /*
2  * This file is subject to the terms and conditions of the GNU General Public
3  * License.  See the file "COPYING" in the main directory of this archive
4  * for more details.
5  *
6  * Copyright (C) 1992 Ross Biro
7  * Copyright (C) Linus Torvalds
8  * Copyright (C) 1994, 95, 96, 97, 98, 2000 Ralf Baechle
9  * Copyright (C) 1996 David S. Miller
10  * Kevin D. Kissell, kevink@mips.com and Carsten Langgaard, carstenl@mips.com
11  * Copyright (C) 1999 MIPS Technologies, Inc.
12  * Copyright (C) 2000 Ulf Carlsson
13  *
14  * At this time Linux/MIPS64 only supports syscall tracing, even for 32-bit
15  * binaries.
16  */
17 #include <linux/compiler.h>
18 #include <linux/context_tracking.h>
19 #include <linux/elf.h>
20 #include <linux/kernel.h>
21 #include <linux/sched.h>
22 #include <linux/sched/task_stack.h>
23 #include <linux/mm.h>
24 #include <linux/errno.h>
25 #include <linux/ptrace.h>
26 #include <linux/regset.h>
27 #include <linux/smp.h>
28 #include <linux/security.h>
29 #include <linux/stddef.h>
30 #include <linux/tracehook.h>
31 #include <linux/audit.h>
32 #include <linux/seccomp.h>
33 #include <linux/ftrace.h>
34 
35 #include <asm/byteorder.h>
36 #include <asm/cpu.h>
37 #include <asm/cpu-info.h>
38 #include <asm/dsp.h>
39 #include <asm/fpu.h>
40 #include <asm/mipsregs.h>
41 #include <asm/mipsmtregs.h>
42 #include <asm/pgtable.h>
43 #include <asm/page.h>
44 #include <asm/processor.h>
45 #include <asm/syscall.h>
46 #include <linux/uaccess.h>
47 #include <asm/bootinfo.h>
48 #include <asm/reg.h>
49 
50 #define CREATE_TRACE_POINTS
51 #include <trace/events/syscalls.h>
52 
53 static void init_fp_ctx(struct task_struct *target)
54 {
55 	/* If FP has been used then the target already has context */
56 	if (tsk_used_math(target))
57 		return;
58 
59 	/* Begin with data registers set to all 1s... */
60 	memset(&target->thread.fpu.fpr, ~0, sizeof(target->thread.fpu.fpr));
61 
62 	/* FCSR has been preset by `mips_set_personality_nan'.  */
63 
64 	/*
65 	 * Record that the target has "used" math, such that the context
66 	 * just initialised, and any modifications made by the caller,
67 	 * aren't discarded.
68 	 */
69 	set_stopped_child_used_math(target);
70 }
71 
72 /*
73  * Called by kernel/ptrace.c when detaching..
74  *
75  * Make sure single step bits etc are not set.
76  */
77 void ptrace_disable(struct task_struct *child)
78 {
79 	/* Don't load the watchpoint registers for the ex-child. */
80 	clear_tsk_thread_flag(child, TIF_LOAD_WATCH);
81 }
82 
83 /*
84  * Poke at FCSR according to its mask.  Set the Cause bits even
85  * if a corresponding Enable bit is set.  This will be noticed at
86  * the time the thread is switched to and SIGFPE thrown accordingly.
87  */
88 static void ptrace_setfcr31(struct task_struct *child, u32 value)
89 {
90 	u32 fcr31;
91 	u32 mask;
92 
93 	fcr31 = child->thread.fpu.fcr31;
94 	mask = boot_cpu_data.fpu_msk31;
95 	child->thread.fpu.fcr31 = (value & ~mask) | (fcr31 & mask);
96 }
97 
98 /*
99  * Read a general register set.	 We always use the 64-bit format, even
100  * for 32-bit kernels and for 32-bit processes on a 64-bit kernel.
101  * Registers are sign extended to fill the available space.
102  */
103 int ptrace_getregs(struct task_struct *child, struct user_pt_regs __user *data)
104 {
105 	struct pt_regs *regs;
106 	int i;
107 
108 	if (!access_ok(VERIFY_WRITE, data, 38 * 8))
109 		return -EIO;
110 
111 	regs = task_pt_regs(child);
112 
113 	for (i = 0; i < 32; i++)
114 		__put_user((long)regs->regs[i], (__s64 __user *)&data->regs[i]);
115 	__put_user((long)regs->lo, (__s64 __user *)&data->lo);
116 	__put_user((long)regs->hi, (__s64 __user *)&data->hi);
117 	__put_user((long)regs->cp0_epc, (__s64 __user *)&data->cp0_epc);
118 	__put_user((long)regs->cp0_badvaddr, (__s64 __user *)&data->cp0_badvaddr);
119 	__put_user((long)regs->cp0_status, (__s64 __user *)&data->cp0_status);
120 	__put_user((long)regs->cp0_cause, (__s64 __user *)&data->cp0_cause);
121 
122 	return 0;
123 }
124 
125 /*
126  * Write a general register set.  As for PTRACE_GETREGS, we always use
127  * the 64-bit format.  On a 32-bit kernel only the lower order half
128  * (according to endianness) will be used.
129  */
130 int ptrace_setregs(struct task_struct *child, struct user_pt_regs __user *data)
131 {
132 	struct pt_regs *regs;
133 	int i;
134 
135 	if (!access_ok(VERIFY_READ, data, 38 * 8))
136 		return -EIO;
137 
138 	regs = task_pt_regs(child);
139 
140 	for (i = 0; i < 32; i++)
141 		__get_user(regs->regs[i], (__s64 __user *)&data->regs[i]);
142 	__get_user(regs->lo, (__s64 __user *)&data->lo);
143 	__get_user(regs->hi, (__s64 __user *)&data->hi);
144 	__get_user(regs->cp0_epc, (__s64 __user *)&data->cp0_epc);
145 
146 	/* badvaddr, status, and cause may not be written.  */
147 
148 	/* System call number may have been changed */
149 	mips_syscall_update_nr(child, regs);
150 
151 	return 0;
152 }
153 
154 int ptrace_getfpregs(struct task_struct *child, __u32 __user *data)
155 {
156 	int i;
157 
158 	if (!access_ok(VERIFY_WRITE, data, 33 * 8))
159 		return -EIO;
160 
161 	if (tsk_used_math(child)) {
162 		union fpureg *fregs = get_fpu_regs(child);
163 		for (i = 0; i < 32; i++)
164 			__put_user(get_fpr64(&fregs[i], 0),
165 				   i + (__u64 __user *)data);
166 	} else {
167 		for (i = 0; i < 32; i++)
168 			__put_user((__u64) -1, i + (__u64 __user *) data);
169 	}
170 
171 	__put_user(child->thread.fpu.fcr31, data + 64);
172 	__put_user(boot_cpu_data.fpu_id, data + 65);
173 
174 	return 0;
175 }
176 
177 int ptrace_setfpregs(struct task_struct *child, __u32 __user *data)
178 {
179 	union fpureg *fregs;
180 	u64 fpr_val;
181 	u32 value;
182 	int i;
183 
184 	if (!access_ok(VERIFY_READ, data, 33 * 8))
185 		return -EIO;
186 
187 	init_fp_ctx(child);
188 	fregs = get_fpu_regs(child);
189 
190 	for (i = 0; i < 32; i++) {
191 		__get_user(fpr_val, i + (__u64 __user *)data);
192 		set_fpr64(&fregs[i], 0, fpr_val);
193 	}
194 
195 	__get_user(value, data + 64);
196 	ptrace_setfcr31(child, value);
197 
198 	/* FIR may not be written.  */
199 
200 	return 0;
201 }
202 
203 int ptrace_get_watch_regs(struct task_struct *child,
204 			  struct pt_watch_regs __user *addr)
205 {
206 	enum pt_watch_style style;
207 	int i;
208 
209 	if (!cpu_has_watch || boot_cpu_data.watch_reg_use_cnt == 0)
210 		return -EIO;
211 	if (!access_ok(VERIFY_WRITE, addr, sizeof(struct pt_watch_regs)))
212 		return -EIO;
213 
214 #ifdef CONFIG_32BIT
215 	style = pt_watch_style_mips32;
216 #define WATCH_STYLE mips32
217 #else
218 	style = pt_watch_style_mips64;
219 #define WATCH_STYLE mips64
220 #endif
221 
222 	__put_user(style, &addr->style);
223 	__put_user(boot_cpu_data.watch_reg_use_cnt,
224 		   &addr->WATCH_STYLE.num_valid);
225 	for (i = 0; i < boot_cpu_data.watch_reg_use_cnt; i++) {
226 		__put_user(child->thread.watch.mips3264.watchlo[i],
227 			   &addr->WATCH_STYLE.watchlo[i]);
228 		__put_user(child->thread.watch.mips3264.watchhi[i] &
229 				(MIPS_WATCHHI_MASK | MIPS_WATCHHI_IRW),
230 			   &addr->WATCH_STYLE.watchhi[i]);
231 		__put_user(boot_cpu_data.watch_reg_masks[i],
232 			   &addr->WATCH_STYLE.watch_masks[i]);
233 	}
234 	for (; i < 8; i++) {
235 		__put_user(0, &addr->WATCH_STYLE.watchlo[i]);
236 		__put_user(0, &addr->WATCH_STYLE.watchhi[i]);
237 		__put_user(0, &addr->WATCH_STYLE.watch_masks[i]);
238 	}
239 
240 	return 0;
241 }
242 
243 int ptrace_set_watch_regs(struct task_struct *child,
244 			  struct pt_watch_regs __user *addr)
245 {
246 	int i;
247 	int watch_active = 0;
248 	unsigned long lt[NUM_WATCH_REGS];
249 	u16 ht[NUM_WATCH_REGS];
250 
251 	if (!cpu_has_watch || boot_cpu_data.watch_reg_use_cnt == 0)
252 		return -EIO;
253 	if (!access_ok(VERIFY_READ, addr, sizeof(struct pt_watch_regs)))
254 		return -EIO;
255 	/* Check the values. */
256 	for (i = 0; i < boot_cpu_data.watch_reg_use_cnt; i++) {
257 		__get_user(lt[i], &addr->WATCH_STYLE.watchlo[i]);
258 #ifdef CONFIG_32BIT
259 		if (lt[i] & __UA_LIMIT)
260 			return -EINVAL;
261 #else
262 		if (test_tsk_thread_flag(child, TIF_32BIT_ADDR)) {
263 			if (lt[i] & 0xffffffff80000000UL)
264 				return -EINVAL;
265 		} else {
266 			if (lt[i] & __UA_LIMIT)
267 				return -EINVAL;
268 		}
269 #endif
270 		__get_user(ht[i], &addr->WATCH_STYLE.watchhi[i]);
271 		if (ht[i] & ~MIPS_WATCHHI_MASK)
272 			return -EINVAL;
273 	}
274 	/* Install them. */
275 	for (i = 0; i < boot_cpu_data.watch_reg_use_cnt; i++) {
276 		if (lt[i] & MIPS_WATCHLO_IRW)
277 			watch_active = 1;
278 		child->thread.watch.mips3264.watchlo[i] = lt[i];
279 		/* Set the G bit. */
280 		child->thread.watch.mips3264.watchhi[i] = ht[i];
281 	}
282 
283 	if (watch_active)
284 		set_tsk_thread_flag(child, TIF_LOAD_WATCH);
285 	else
286 		clear_tsk_thread_flag(child, TIF_LOAD_WATCH);
287 
288 	return 0;
289 }
290 
291 /* regset get/set implementations */
292 
293 #if defined(CONFIG_32BIT) || defined(CONFIG_MIPS32_O32)
294 
295 static int gpr32_get(struct task_struct *target,
296 		     const struct user_regset *regset,
297 		     unsigned int pos, unsigned int count,
298 		     void *kbuf, void __user *ubuf)
299 {
300 	struct pt_regs *regs = task_pt_regs(target);
301 	u32 uregs[ELF_NGREG] = {};
302 
303 	mips_dump_regs32(uregs, regs);
304 	return user_regset_copyout(&pos, &count, &kbuf, &ubuf, uregs, 0,
305 				   sizeof(uregs));
306 }
307 
308 static int gpr32_set(struct task_struct *target,
309 		     const struct user_regset *regset,
310 		     unsigned int pos, unsigned int count,
311 		     const void *kbuf, const void __user *ubuf)
312 {
313 	struct pt_regs *regs = task_pt_regs(target);
314 	u32 uregs[ELF_NGREG];
315 	unsigned start, num_regs, i;
316 	int err;
317 
318 	start = pos / sizeof(u32);
319 	num_regs = count / sizeof(u32);
320 
321 	if (start + num_regs > ELF_NGREG)
322 		return -EIO;
323 
324 	err = user_regset_copyin(&pos, &count, &kbuf, &ubuf, uregs, 0,
325 				 sizeof(uregs));
326 	if (err)
327 		return err;
328 
329 	for (i = start; i < num_regs; i++) {
330 		/*
331 		 * Cast all values to signed here so that if this is a 64-bit
332 		 * kernel, the supplied 32-bit values will be sign extended.
333 		 */
334 		switch (i) {
335 		case MIPS32_EF_R1 ... MIPS32_EF_R25:
336 			/* k0/k1 are ignored. */
337 		case MIPS32_EF_R28 ... MIPS32_EF_R31:
338 			regs->regs[i - MIPS32_EF_R0] = (s32)uregs[i];
339 			break;
340 		case MIPS32_EF_LO:
341 			regs->lo = (s32)uregs[i];
342 			break;
343 		case MIPS32_EF_HI:
344 			regs->hi = (s32)uregs[i];
345 			break;
346 		case MIPS32_EF_CP0_EPC:
347 			regs->cp0_epc = (s32)uregs[i];
348 			break;
349 		}
350 	}
351 
352 	/* System call number may have been changed */
353 	mips_syscall_update_nr(target, regs);
354 
355 	return 0;
356 }
357 
358 #endif /* CONFIG_32BIT || CONFIG_MIPS32_O32 */
359 
360 #ifdef CONFIG_64BIT
361 
362 static int gpr64_get(struct task_struct *target,
363 		     const struct user_regset *regset,
364 		     unsigned int pos, unsigned int count,
365 		     void *kbuf, void __user *ubuf)
366 {
367 	struct pt_regs *regs = task_pt_regs(target);
368 	u64 uregs[ELF_NGREG] = {};
369 
370 	mips_dump_regs64(uregs, regs);
371 	return user_regset_copyout(&pos, &count, &kbuf, &ubuf, uregs, 0,
372 				   sizeof(uregs));
373 }
374 
375 static int gpr64_set(struct task_struct *target,
376 		     const struct user_regset *regset,
377 		     unsigned int pos, unsigned int count,
378 		     const void *kbuf, const void __user *ubuf)
379 {
380 	struct pt_regs *regs = task_pt_regs(target);
381 	u64 uregs[ELF_NGREG];
382 	unsigned start, num_regs, i;
383 	int err;
384 
385 	start = pos / sizeof(u64);
386 	num_regs = count / sizeof(u64);
387 
388 	if (start + num_regs > ELF_NGREG)
389 		return -EIO;
390 
391 	err = user_regset_copyin(&pos, &count, &kbuf, &ubuf, uregs, 0,
392 				 sizeof(uregs));
393 	if (err)
394 		return err;
395 
396 	for (i = start; i < num_regs; i++) {
397 		switch (i) {
398 		case MIPS64_EF_R1 ... MIPS64_EF_R25:
399 			/* k0/k1 are ignored. */
400 		case MIPS64_EF_R28 ... MIPS64_EF_R31:
401 			regs->regs[i - MIPS64_EF_R0] = uregs[i];
402 			break;
403 		case MIPS64_EF_LO:
404 			regs->lo = uregs[i];
405 			break;
406 		case MIPS64_EF_HI:
407 			regs->hi = uregs[i];
408 			break;
409 		case MIPS64_EF_CP0_EPC:
410 			regs->cp0_epc = uregs[i];
411 			break;
412 		}
413 	}
414 
415 	/* System call number may have been changed */
416 	mips_syscall_update_nr(target, regs);
417 
418 	return 0;
419 }
420 
421 #endif /* CONFIG_64BIT */
422 
423 /*
424  * Copy the floating-point context to the supplied NT_PRFPREG buffer,
425  * !CONFIG_CPU_HAS_MSA variant.  FP context's general register slots
426  * correspond 1:1 to buffer slots.  Only general registers are copied.
427  */
428 static int fpr_get_fpa(struct task_struct *target,
429 		       unsigned int *pos, unsigned int *count,
430 		       void **kbuf, void __user **ubuf)
431 {
432 	return user_regset_copyout(pos, count, kbuf, ubuf,
433 				   &target->thread.fpu,
434 				   0, NUM_FPU_REGS * sizeof(elf_fpreg_t));
435 }
436 
437 /*
438  * Copy the floating-point context to the supplied NT_PRFPREG buffer,
439  * CONFIG_CPU_HAS_MSA variant.  Only lower 64 bits of FP context's
440  * general register slots are copied to buffer slots.  Only general
441  * registers are copied.
442  */
443 static int fpr_get_msa(struct task_struct *target,
444 		       unsigned int *pos, unsigned int *count,
445 		       void **kbuf, void __user **ubuf)
446 {
447 	unsigned int i;
448 	u64 fpr_val;
449 	int err;
450 
451 	BUILD_BUG_ON(sizeof(fpr_val) != sizeof(elf_fpreg_t));
452 	for (i = 0; i < NUM_FPU_REGS; i++) {
453 		fpr_val = get_fpr64(&target->thread.fpu.fpr[i], 0);
454 		err = user_regset_copyout(pos, count, kbuf, ubuf,
455 					  &fpr_val, i * sizeof(elf_fpreg_t),
456 					  (i + 1) * sizeof(elf_fpreg_t));
457 		if (err)
458 			return err;
459 	}
460 
461 	return 0;
462 }
463 
464 /*
465  * Copy the floating-point context to the supplied NT_PRFPREG buffer.
466  * Choose the appropriate helper for general registers, and then copy
467  * the FCSR and FIR registers separately.
468  */
469 static int fpr_get(struct task_struct *target,
470 		   const struct user_regset *regset,
471 		   unsigned int pos, unsigned int count,
472 		   void *kbuf, void __user *ubuf)
473 {
474 	const int fcr31_pos = NUM_FPU_REGS * sizeof(elf_fpreg_t);
475 	const int fir_pos = fcr31_pos + sizeof(u32);
476 	int err;
477 
478 	if (sizeof(target->thread.fpu.fpr[0]) == sizeof(elf_fpreg_t))
479 		err = fpr_get_fpa(target, &pos, &count, &kbuf, &ubuf);
480 	else
481 		err = fpr_get_msa(target, &pos, &count, &kbuf, &ubuf);
482 	if (err)
483 		return err;
484 
485 	err = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
486 				  &target->thread.fpu.fcr31,
487 				  fcr31_pos, fcr31_pos + sizeof(u32));
488 	if (err)
489 		return err;
490 
491 	err = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
492 				  &boot_cpu_data.fpu_id,
493 				  fir_pos, fir_pos + sizeof(u32));
494 
495 	return err;
496 }
497 
498 /*
499  * Copy the supplied NT_PRFPREG buffer to the floating-point context,
500  * !CONFIG_CPU_HAS_MSA variant.   Buffer slots correspond 1:1 to FP
501  * context's general register slots.  Only general registers are copied.
502  */
503 static int fpr_set_fpa(struct task_struct *target,
504 		       unsigned int *pos, unsigned int *count,
505 		       const void **kbuf, const void __user **ubuf)
506 {
507 	return user_regset_copyin(pos, count, kbuf, ubuf,
508 				  &target->thread.fpu,
509 				  0, NUM_FPU_REGS * sizeof(elf_fpreg_t));
510 }
511 
512 /*
513  * Copy the supplied NT_PRFPREG buffer to the floating-point context,
514  * CONFIG_CPU_HAS_MSA variant.  Buffer slots are copied to lower 64
515  * bits only of FP context's general register slots.  Only general
516  * registers are copied.
517  */
518 static int fpr_set_msa(struct task_struct *target,
519 		       unsigned int *pos, unsigned int *count,
520 		       const void **kbuf, const void __user **ubuf)
521 {
522 	unsigned int i;
523 	u64 fpr_val;
524 	int err;
525 
526 	BUILD_BUG_ON(sizeof(fpr_val) != sizeof(elf_fpreg_t));
527 	for (i = 0; i < NUM_FPU_REGS && *count > 0; i++) {
528 		err = user_regset_copyin(pos, count, kbuf, ubuf,
529 					 &fpr_val, i * sizeof(elf_fpreg_t),
530 					 (i + 1) * sizeof(elf_fpreg_t));
531 		if (err)
532 			return err;
533 		set_fpr64(&target->thread.fpu.fpr[i], 0, fpr_val);
534 	}
535 
536 	return 0;
537 }
538 
539 /*
540  * Copy the supplied NT_PRFPREG buffer to the floating-point context.
541  * Choose the appropriate helper for general registers, and then copy
542  * the FCSR register separately.  Ignore the incoming FIR register
543  * contents though, as the register is read-only.
544  *
545  * We optimize for the case where `count % sizeof(elf_fpreg_t) == 0',
546  * which is supposed to have been guaranteed by the kernel before
547  * calling us, e.g. in `ptrace_regset'.  We enforce that requirement,
548  * so that we can safely avoid preinitializing temporaries for
549  * partial register writes.
550  */
551 static int fpr_set(struct task_struct *target,
552 		   const struct user_regset *regset,
553 		   unsigned int pos, unsigned int count,
554 		   const void *kbuf, const void __user *ubuf)
555 {
556 	const int fcr31_pos = NUM_FPU_REGS * sizeof(elf_fpreg_t);
557 	const int fir_pos = fcr31_pos + sizeof(u32);
558 	u32 fcr31;
559 	int err;
560 
561 	BUG_ON(count % sizeof(elf_fpreg_t));
562 
563 	if (pos + count > sizeof(elf_fpregset_t))
564 		return -EIO;
565 
566 	init_fp_ctx(target);
567 
568 	if (sizeof(target->thread.fpu.fpr[0]) == sizeof(elf_fpreg_t))
569 		err = fpr_set_fpa(target, &pos, &count, &kbuf, &ubuf);
570 	else
571 		err = fpr_set_msa(target, &pos, &count, &kbuf, &ubuf);
572 	if (err)
573 		return err;
574 
575 	if (count > 0) {
576 		err = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
577 					 &fcr31,
578 					 fcr31_pos, fcr31_pos + sizeof(u32));
579 		if (err)
580 			return err;
581 
582 		ptrace_setfcr31(target, fcr31);
583 	}
584 
585 	if (count > 0)
586 		err = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
587 						fir_pos,
588 						fir_pos + sizeof(u32));
589 
590 	return err;
591 }
592 
593 #if defined(CONFIG_32BIT) || defined(CONFIG_MIPS32_O32)
594 
595 /*
596  * Copy the DSP context to the supplied 32-bit NT_MIPS_DSP buffer.
597  */
598 static int dsp32_get(struct task_struct *target,
599 		     const struct user_regset *regset,
600 		     unsigned int pos, unsigned int count,
601 		     void *kbuf, void __user *ubuf)
602 {
603 	unsigned int start, num_regs, i;
604 	u32 dspregs[NUM_DSP_REGS + 1];
605 
606 	BUG_ON(count % sizeof(u32));
607 
608 	if (!cpu_has_dsp)
609 		return -EIO;
610 
611 	start = pos / sizeof(u32);
612 	num_regs = count / sizeof(u32);
613 
614 	if (start + num_regs > NUM_DSP_REGS + 1)
615 		return -EIO;
616 
617 	for (i = start; i < num_regs; i++)
618 		switch (i) {
619 		case 0 ... NUM_DSP_REGS - 1:
620 			dspregs[i] = target->thread.dsp.dspr[i];
621 			break;
622 		case NUM_DSP_REGS:
623 			dspregs[i] = target->thread.dsp.dspcontrol;
624 			break;
625 		}
626 	return user_regset_copyout(&pos, &count, &kbuf, &ubuf, dspregs, 0,
627 				   sizeof(dspregs));
628 }
629 
630 /*
631  * Copy the supplied 32-bit NT_MIPS_DSP buffer to the DSP context.
632  */
633 static int dsp32_set(struct task_struct *target,
634 		     const struct user_regset *regset,
635 		     unsigned int pos, unsigned int count,
636 		     const void *kbuf, const void __user *ubuf)
637 {
638 	unsigned int start, num_regs, i;
639 	u32 dspregs[NUM_DSP_REGS + 1];
640 	int err;
641 
642 	BUG_ON(count % sizeof(u32));
643 
644 	if (!cpu_has_dsp)
645 		return -EIO;
646 
647 	start = pos / sizeof(u32);
648 	num_regs = count / sizeof(u32);
649 
650 	if (start + num_regs > NUM_DSP_REGS + 1)
651 		return -EIO;
652 
653 	err = user_regset_copyin(&pos, &count, &kbuf, &ubuf, dspregs, 0,
654 				 sizeof(dspregs));
655 	if (err)
656 		return err;
657 
658 	for (i = start; i < num_regs; i++)
659 		switch (i) {
660 		case 0 ... NUM_DSP_REGS - 1:
661 			target->thread.dsp.dspr[i] = (s32)dspregs[i];
662 			break;
663 		case NUM_DSP_REGS:
664 			target->thread.dsp.dspcontrol = (s32)dspregs[i];
665 			break;
666 		}
667 
668 	return 0;
669 }
670 
671 #endif /* CONFIG_32BIT || CONFIG_MIPS32_O32 */
672 
673 #ifdef CONFIG_64BIT
674 
675 /*
676  * Copy the DSP context to the supplied 64-bit NT_MIPS_DSP buffer.
677  */
678 static int dsp64_get(struct task_struct *target,
679 		     const struct user_regset *regset,
680 		     unsigned int pos, unsigned int count,
681 		     void *kbuf, void __user *ubuf)
682 {
683 	unsigned int start, num_regs, i;
684 	u64 dspregs[NUM_DSP_REGS + 1];
685 
686 	BUG_ON(count % sizeof(u64));
687 
688 	if (!cpu_has_dsp)
689 		return -EIO;
690 
691 	start = pos / sizeof(u64);
692 	num_regs = count / sizeof(u64);
693 
694 	if (start + num_regs > NUM_DSP_REGS + 1)
695 		return -EIO;
696 
697 	for (i = start; i < num_regs; i++)
698 		switch (i) {
699 		case 0 ... NUM_DSP_REGS - 1:
700 			dspregs[i] = target->thread.dsp.dspr[i];
701 			break;
702 		case NUM_DSP_REGS:
703 			dspregs[i] = target->thread.dsp.dspcontrol;
704 			break;
705 		}
706 	return user_regset_copyout(&pos, &count, &kbuf, &ubuf, dspregs, 0,
707 				   sizeof(dspregs));
708 }
709 
710 /*
711  * Copy the supplied 64-bit NT_MIPS_DSP buffer to the DSP context.
712  */
713 static int dsp64_set(struct task_struct *target,
714 		     const struct user_regset *regset,
715 		     unsigned int pos, unsigned int count,
716 		     const void *kbuf, const void __user *ubuf)
717 {
718 	unsigned int start, num_regs, i;
719 	u64 dspregs[NUM_DSP_REGS + 1];
720 	int err;
721 
722 	BUG_ON(count % sizeof(u64));
723 
724 	if (!cpu_has_dsp)
725 		return -EIO;
726 
727 	start = pos / sizeof(u64);
728 	num_regs = count / sizeof(u64);
729 
730 	if (start + num_regs > NUM_DSP_REGS + 1)
731 		return -EIO;
732 
733 	err = user_regset_copyin(&pos, &count, &kbuf, &ubuf, dspregs, 0,
734 				 sizeof(dspregs));
735 	if (err)
736 		return err;
737 
738 	for (i = start; i < num_regs; i++)
739 		switch (i) {
740 		case 0 ... NUM_DSP_REGS - 1:
741 			target->thread.dsp.dspr[i] = dspregs[i];
742 			break;
743 		case NUM_DSP_REGS:
744 			target->thread.dsp.dspcontrol = dspregs[i];
745 			break;
746 		}
747 
748 	return 0;
749 }
750 
751 #endif /* CONFIG_64BIT */
752 
753 /*
754  * Determine whether the DSP context is present.
755  */
756 static int dsp_active(struct task_struct *target,
757 		      const struct user_regset *regset)
758 {
759 	return cpu_has_dsp ? NUM_DSP_REGS + 1 : -ENODEV;
760 }
761 
762 /* Copy the FP mode setting to the supplied NT_MIPS_FP_MODE buffer.  */
763 static int fp_mode_get(struct task_struct *target,
764 		       const struct user_regset *regset,
765 		       unsigned int pos, unsigned int count,
766 		       void *kbuf, void __user *ubuf)
767 {
768 	int fp_mode;
769 
770 	fp_mode = mips_get_process_fp_mode(target);
771 	return user_regset_copyout(&pos, &count, &kbuf, &ubuf, &fp_mode, 0,
772 				   sizeof(fp_mode));
773 }
774 
775 /*
776  * Copy the supplied NT_MIPS_FP_MODE buffer to the FP mode setting.
777  *
778  * We optimize for the case where `count % sizeof(int) == 0', which
779  * is supposed to have been guaranteed by the kernel before calling
780  * us, e.g. in `ptrace_regset'.  We enforce that requirement, so
781  * that we can safely avoid preinitializing temporaries for partial
782  * mode writes.
783  */
784 static int fp_mode_set(struct task_struct *target,
785 		       const struct user_regset *regset,
786 		       unsigned int pos, unsigned int count,
787 		       const void *kbuf, const void __user *ubuf)
788 {
789 	int fp_mode;
790 	int err;
791 
792 	BUG_ON(count % sizeof(int));
793 
794 	if (pos + count > sizeof(fp_mode))
795 		return -EIO;
796 
797 	err = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &fp_mode, 0,
798 				 sizeof(fp_mode));
799 	if (err)
800 		return err;
801 
802 	if (count > 0)
803 		err = mips_set_process_fp_mode(target, fp_mode);
804 
805 	return err;
806 }
807 
808 enum mips_regset {
809 	REGSET_GPR,
810 	REGSET_FPR,
811 	REGSET_DSP,
812 	REGSET_FP_MODE,
813 };
814 
815 struct pt_regs_offset {
816 	const char *name;
817 	int offset;
818 };
819 
820 #define REG_OFFSET_NAME(reg, r) {					\
821 	.name = #reg,							\
822 	.offset = offsetof(struct pt_regs, r)				\
823 }
824 
825 #define REG_OFFSET_END {						\
826 	.name = NULL,							\
827 	.offset = 0							\
828 }
829 
830 static const struct pt_regs_offset regoffset_table[] = {
831 	REG_OFFSET_NAME(r0, regs[0]),
832 	REG_OFFSET_NAME(r1, regs[1]),
833 	REG_OFFSET_NAME(r2, regs[2]),
834 	REG_OFFSET_NAME(r3, regs[3]),
835 	REG_OFFSET_NAME(r4, regs[4]),
836 	REG_OFFSET_NAME(r5, regs[5]),
837 	REG_OFFSET_NAME(r6, regs[6]),
838 	REG_OFFSET_NAME(r7, regs[7]),
839 	REG_OFFSET_NAME(r8, regs[8]),
840 	REG_OFFSET_NAME(r9, regs[9]),
841 	REG_OFFSET_NAME(r10, regs[10]),
842 	REG_OFFSET_NAME(r11, regs[11]),
843 	REG_OFFSET_NAME(r12, regs[12]),
844 	REG_OFFSET_NAME(r13, regs[13]),
845 	REG_OFFSET_NAME(r14, regs[14]),
846 	REG_OFFSET_NAME(r15, regs[15]),
847 	REG_OFFSET_NAME(r16, regs[16]),
848 	REG_OFFSET_NAME(r17, regs[17]),
849 	REG_OFFSET_NAME(r18, regs[18]),
850 	REG_OFFSET_NAME(r19, regs[19]),
851 	REG_OFFSET_NAME(r20, regs[20]),
852 	REG_OFFSET_NAME(r21, regs[21]),
853 	REG_OFFSET_NAME(r22, regs[22]),
854 	REG_OFFSET_NAME(r23, regs[23]),
855 	REG_OFFSET_NAME(r24, regs[24]),
856 	REG_OFFSET_NAME(r25, regs[25]),
857 	REG_OFFSET_NAME(r26, regs[26]),
858 	REG_OFFSET_NAME(r27, regs[27]),
859 	REG_OFFSET_NAME(r28, regs[28]),
860 	REG_OFFSET_NAME(r29, regs[29]),
861 	REG_OFFSET_NAME(r30, regs[30]),
862 	REG_OFFSET_NAME(r31, regs[31]),
863 	REG_OFFSET_NAME(c0_status, cp0_status),
864 	REG_OFFSET_NAME(hi, hi),
865 	REG_OFFSET_NAME(lo, lo),
866 #ifdef CONFIG_CPU_HAS_SMARTMIPS
867 	REG_OFFSET_NAME(acx, acx),
868 #endif
869 	REG_OFFSET_NAME(c0_badvaddr, cp0_badvaddr),
870 	REG_OFFSET_NAME(c0_cause, cp0_cause),
871 	REG_OFFSET_NAME(c0_epc, cp0_epc),
872 #ifdef CONFIG_CPU_CAVIUM_OCTEON
873 	REG_OFFSET_NAME(mpl0, mpl[0]),
874 	REG_OFFSET_NAME(mpl1, mpl[1]),
875 	REG_OFFSET_NAME(mpl2, mpl[2]),
876 	REG_OFFSET_NAME(mtp0, mtp[0]),
877 	REG_OFFSET_NAME(mtp1, mtp[1]),
878 	REG_OFFSET_NAME(mtp2, mtp[2]),
879 #endif
880 	REG_OFFSET_END,
881 };
882 
883 /**
884  * regs_query_register_offset() - query register offset from its name
885  * @name:       the name of a register
886  *
887  * regs_query_register_offset() returns the offset of a register in struct
888  * pt_regs from its name. If the name is invalid, this returns -EINVAL;
889  */
890 int regs_query_register_offset(const char *name)
891 {
892         const struct pt_regs_offset *roff;
893         for (roff = regoffset_table; roff->name != NULL; roff++)
894                 if (!strcmp(roff->name, name))
895                         return roff->offset;
896         return -EINVAL;
897 }
898 
899 #if defined(CONFIG_32BIT) || defined(CONFIG_MIPS32_O32)
900 
901 static const struct user_regset mips_regsets[] = {
902 	[REGSET_GPR] = {
903 		.core_note_type	= NT_PRSTATUS,
904 		.n		= ELF_NGREG,
905 		.size		= sizeof(unsigned int),
906 		.align		= sizeof(unsigned int),
907 		.get		= gpr32_get,
908 		.set		= gpr32_set,
909 	},
910 	[REGSET_FPR] = {
911 		.core_note_type	= NT_PRFPREG,
912 		.n		= ELF_NFPREG,
913 		.size		= sizeof(elf_fpreg_t),
914 		.align		= sizeof(elf_fpreg_t),
915 		.get		= fpr_get,
916 		.set		= fpr_set,
917 	},
918 	[REGSET_DSP] = {
919 		.core_note_type	= NT_MIPS_DSP,
920 		.n		= NUM_DSP_REGS + 1,
921 		.size		= sizeof(u32),
922 		.align		= sizeof(u32),
923 		.get		= dsp32_get,
924 		.set		= dsp32_set,
925 		.active		= dsp_active,
926 	},
927 	[REGSET_FP_MODE] = {
928 		.core_note_type	= NT_MIPS_FP_MODE,
929 		.n		= 1,
930 		.size		= sizeof(int),
931 		.align		= sizeof(int),
932 		.get		= fp_mode_get,
933 		.set		= fp_mode_set,
934 	},
935 };
936 
937 static const struct user_regset_view user_mips_view = {
938 	.name		= "mips",
939 	.e_machine	= ELF_ARCH,
940 	.ei_osabi	= ELF_OSABI,
941 	.regsets	= mips_regsets,
942 	.n		= ARRAY_SIZE(mips_regsets),
943 };
944 
945 #endif /* CONFIG_32BIT || CONFIG_MIPS32_O32 */
946 
947 #ifdef CONFIG_64BIT
948 
949 static const struct user_regset mips64_regsets[] = {
950 	[REGSET_GPR] = {
951 		.core_note_type	= NT_PRSTATUS,
952 		.n		= ELF_NGREG,
953 		.size		= sizeof(unsigned long),
954 		.align		= sizeof(unsigned long),
955 		.get		= gpr64_get,
956 		.set		= gpr64_set,
957 	},
958 	[REGSET_FPR] = {
959 		.core_note_type	= NT_PRFPREG,
960 		.n		= ELF_NFPREG,
961 		.size		= sizeof(elf_fpreg_t),
962 		.align		= sizeof(elf_fpreg_t),
963 		.get		= fpr_get,
964 		.set		= fpr_set,
965 	},
966 	[REGSET_DSP] = {
967 		.core_note_type	= NT_MIPS_DSP,
968 		.n		= NUM_DSP_REGS + 1,
969 		.size		= sizeof(u64),
970 		.align		= sizeof(u64),
971 		.get		= dsp64_get,
972 		.set		= dsp64_set,
973 		.active		= dsp_active,
974 	},
975 	[REGSET_FP_MODE] = {
976 		.core_note_type	= NT_MIPS_FP_MODE,
977 		.n		= 1,
978 		.size		= sizeof(int),
979 		.align		= sizeof(int),
980 		.get		= fp_mode_get,
981 		.set		= fp_mode_set,
982 	},
983 };
984 
985 static const struct user_regset_view user_mips64_view = {
986 	.name		= "mips64",
987 	.e_machine	= ELF_ARCH,
988 	.ei_osabi	= ELF_OSABI,
989 	.regsets	= mips64_regsets,
990 	.n		= ARRAY_SIZE(mips64_regsets),
991 };
992 
993 #ifdef CONFIG_MIPS32_N32
994 
995 static const struct user_regset_view user_mipsn32_view = {
996 	.name		= "mipsn32",
997 	.e_flags	= EF_MIPS_ABI2,
998 	.e_machine	= ELF_ARCH,
999 	.ei_osabi	= ELF_OSABI,
1000 	.regsets	= mips64_regsets,
1001 	.n		= ARRAY_SIZE(mips64_regsets),
1002 };
1003 
1004 #endif /* CONFIG_MIPS32_N32 */
1005 
1006 #endif /* CONFIG_64BIT */
1007 
1008 const struct user_regset_view *task_user_regset_view(struct task_struct *task)
1009 {
1010 #ifdef CONFIG_32BIT
1011 	return &user_mips_view;
1012 #else
1013 #ifdef CONFIG_MIPS32_O32
1014 	if (test_tsk_thread_flag(task, TIF_32BIT_REGS))
1015 		return &user_mips_view;
1016 #endif
1017 #ifdef CONFIG_MIPS32_N32
1018 	if (test_tsk_thread_flag(task, TIF_32BIT_ADDR))
1019 		return &user_mipsn32_view;
1020 #endif
1021 	return &user_mips64_view;
1022 #endif
1023 }
1024 
1025 long arch_ptrace(struct task_struct *child, long request,
1026 		 unsigned long addr, unsigned long data)
1027 {
1028 	int ret;
1029 	void __user *addrp = (void __user *) addr;
1030 	void __user *datavp = (void __user *) data;
1031 	unsigned long __user *datalp = (void __user *) data;
1032 
1033 	switch (request) {
1034 	/* when I and D space are separate, these will need to be fixed. */
1035 	case PTRACE_PEEKTEXT: /* read word at location addr. */
1036 	case PTRACE_PEEKDATA:
1037 		ret = generic_ptrace_peekdata(child, addr, data);
1038 		break;
1039 
1040 	/* Read the word at location addr in the USER area. */
1041 	case PTRACE_PEEKUSR: {
1042 		struct pt_regs *regs;
1043 		union fpureg *fregs;
1044 		unsigned long tmp = 0;
1045 
1046 		regs = task_pt_regs(child);
1047 		ret = 0;  /* Default return value. */
1048 
1049 		switch (addr) {
1050 		case 0 ... 31:
1051 			tmp = regs->regs[addr];
1052 			break;
1053 		case FPR_BASE ... FPR_BASE + 31:
1054 			if (!tsk_used_math(child)) {
1055 				/* FP not yet used */
1056 				tmp = -1;
1057 				break;
1058 			}
1059 			fregs = get_fpu_regs(child);
1060 
1061 #ifdef CONFIG_32BIT
1062 			if (test_tsk_thread_flag(child, TIF_32BIT_FPREGS)) {
1063 				/*
1064 				 * The odd registers are actually the high
1065 				 * order bits of the values stored in the even
1066 				 * registers.
1067 				 */
1068 				tmp = get_fpr32(&fregs[(addr & ~1) - FPR_BASE],
1069 						addr & 1);
1070 				break;
1071 			}
1072 #endif
1073 			tmp = get_fpr64(&fregs[addr - FPR_BASE], 0);
1074 			break;
1075 		case PC:
1076 			tmp = regs->cp0_epc;
1077 			break;
1078 		case CAUSE:
1079 			tmp = regs->cp0_cause;
1080 			break;
1081 		case BADVADDR:
1082 			tmp = regs->cp0_badvaddr;
1083 			break;
1084 		case MMHI:
1085 			tmp = regs->hi;
1086 			break;
1087 		case MMLO:
1088 			tmp = regs->lo;
1089 			break;
1090 #ifdef CONFIG_CPU_HAS_SMARTMIPS
1091 		case ACX:
1092 			tmp = regs->acx;
1093 			break;
1094 #endif
1095 		case FPC_CSR:
1096 			tmp = child->thread.fpu.fcr31;
1097 			break;
1098 		case FPC_EIR:
1099 			/* implementation / version register */
1100 			tmp = boot_cpu_data.fpu_id;
1101 			break;
1102 		case DSP_BASE ... DSP_BASE + 5: {
1103 			dspreg_t *dregs;
1104 
1105 			if (!cpu_has_dsp) {
1106 				tmp = 0;
1107 				ret = -EIO;
1108 				goto out;
1109 			}
1110 			dregs = __get_dsp_regs(child);
1111 			tmp = dregs[addr - DSP_BASE];
1112 			break;
1113 		}
1114 		case DSP_CONTROL:
1115 			if (!cpu_has_dsp) {
1116 				tmp = 0;
1117 				ret = -EIO;
1118 				goto out;
1119 			}
1120 			tmp = child->thread.dsp.dspcontrol;
1121 			break;
1122 		default:
1123 			tmp = 0;
1124 			ret = -EIO;
1125 			goto out;
1126 		}
1127 		ret = put_user(tmp, datalp);
1128 		break;
1129 	}
1130 
1131 	/* when I and D space are separate, this will have to be fixed. */
1132 	case PTRACE_POKETEXT: /* write the word at location addr. */
1133 	case PTRACE_POKEDATA:
1134 		ret = generic_ptrace_pokedata(child, addr, data);
1135 		break;
1136 
1137 	case PTRACE_POKEUSR: {
1138 		struct pt_regs *regs;
1139 		ret = 0;
1140 		regs = task_pt_regs(child);
1141 
1142 		switch (addr) {
1143 		case 0 ... 31:
1144 			regs->regs[addr] = data;
1145 			/* System call number may have been changed */
1146 			if (addr == 2)
1147 				mips_syscall_update_nr(child, regs);
1148 			else if (addr == 4 &&
1149 				 mips_syscall_is_indirect(child, regs))
1150 				mips_syscall_update_nr(child, regs);
1151 			break;
1152 		case FPR_BASE ... FPR_BASE + 31: {
1153 			union fpureg *fregs = get_fpu_regs(child);
1154 
1155 			init_fp_ctx(child);
1156 #ifdef CONFIG_32BIT
1157 			if (test_tsk_thread_flag(child, TIF_32BIT_FPREGS)) {
1158 				/*
1159 				 * The odd registers are actually the high
1160 				 * order bits of the values stored in the even
1161 				 * registers.
1162 				 */
1163 				set_fpr32(&fregs[(addr & ~1) - FPR_BASE],
1164 					  addr & 1, data);
1165 				break;
1166 			}
1167 #endif
1168 			set_fpr64(&fregs[addr - FPR_BASE], 0, data);
1169 			break;
1170 		}
1171 		case PC:
1172 			regs->cp0_epc = data;
1173 			break;
1174 		case MMHI:
1175 			regs->hi = data;
1176 			break;
1177 		case MMLO:
1178 			regs->lo = data;
1179 			break;
1180 #ifdef CONFIG_CPU_HAS_SMARTMIPS
1181 		case ACX:
1182 			regs->acx = data;
1183 			break;
1184 #endif
1185 		case FPC_CSR:
1186 			init_fp_ctx(child);
1187 			ptrace_setfcr31(child, data);
1188 			break;
1189 		case DSP_BASE ... DSP_BASE + 5: {
1190 			dspreg_t *dregs;
1191 
1192 			if (!cpu_has_dsp) {
1193 				ret = -EIO;
1194 				break;
1195 			}
1196 
1197 			dregs = __get_dsp_regs(child);
1198 			dregs[addr - DSP_BASE] = data;
1199 			break;
1200 		}
1201 		case DSP_CONTROL:
1202 			if (!cpu_has_dsp) {
1203 				ret = -EIO;
1204 				break;
1205 			}
1206 			child->thread.dsp.dspcontrol = data;
1207 			break;
1208 		default:
1209 			/* The rest are not allowed. */
1210 			ret = -EIO;
1211 			break;
1212 		}
1213 		break;
1214 		}
1215 
1216 	case PTRACE_GETREGS:
1217 		ret = ptrace_getregs(child, datavp);
1218 		break;
1219 
1220 	case PTRACE_SETREGS:
1221 		ret = ptrace_setregs(child, datavp);
1222 		break;
1223 
1224 	case PTRACE_GETFPREGS:
1225 		ret = ptrace_getfpregs(child, datavp);
1226 		break;
1227 
1228 	case PTRACE_SETFPREGS:
1229 		ret = ptrace_setfpregs(child, datavp);
1230 		break;
1231 
1232 	case PTRACE_GET_THREAD_AREA:
1233 		ret = put_user(task_thread_info(child)->tp_value, datalp);
1234 		break;
1235 
1236 	case PTRACE_GET_WATCH_REGS:
1237 		ret = ptrace_get_watch_regs(child, addrp);
1238 		break;
1239 
1240 	case PTRACE_SET_WATCH_REGS:
1241 		ret = ptrace_set_watch_regs(child, addrp);
1242 		break;
1243 
1244 	default:
1245 		ret = ptrace_request(child, request, addr, data);
1246 		break;
1247 	}
1248  out:
1249 	return ret;
1250 }
1251 
1252 /*
1253  * Notification of system call entry/exit
1254  * - triggered by current->work.syscall_trace
1255  */
1256 asmlinkage long syscall_trace_enter(struct pt_regs *regs, long syscall)
1257 {
1258 	user_exit();
1259 
1260 	current_thread_info()->syscall = syscall;
1261 
1262 	if (test_thread_flag(TIF_SYSCALL_TRACE)) {
1263 		if (tracehook_report_syscall_entry(regs))
1264 			return -1;
1265 		syscall = current_thread_info()->syscall;
1266 	}
1267 
1268 #ifdef CONFIG_SECCOMP
1269 	if (unlikely(test_thread_flag(TIF_SECCOMP))) {
1270 		int ret, i;
1271 		struct seccomp_data sd;
1272 		unsigned long args[6];
1273 
1274 		sd.nr = syscall;
1275 		sd.arch = syscall_get_arch();
1276 		syscall_get_arguments(current, regs, 0, 6, args);
1277 		for (i = 0; i < 6; i++)
1278 			sd.args[i] = args[i];
1279 		sd.instruction_pointer = KSTK_EIP(current);
1280 
1281 		ret = __secure_computing(&sd);
1282 		if (ret == -1)
1283 			return ret;
1284 		syscall = current_thread_info()->syscall;
1285 	}
1286 #endif
1287 
1288 	if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
1289 		trace_sys_enter(regs, regs->regs[2]);
1290 
1291 	audit_syscall_entry(syscall, regs->regs[4], regs->regs[5],
1292 			    regs->regs[6], regs->regs[7]);
1293 
1294 	/*
1295 	 * Negative syscall numbers are mistaken for rejected syscalls, but
1296 	 * won't have had the return value set appropriately, so we do so now.
1297 	 */
1298 	if (syscall < 0)
1299 		syscall_set_return_value(current, regs, -ENOSYS, 0);
1300 	return syscall;
1301 }
1302 
1303 /*
1304  * Notification of system call entry/exit
1305  * - triggered by current->work.syscall_trace
1306  */
1307 asmlinkage void syscall_trace_leave(struct pt_regs *regs)
1308 {
1309         /*
1310 	 * We may come here right after calling schedule_user()
1311 	 * or do_notify_resume(), in which case we can be in RCU
1312 	 * user mode.
1313 	 */
1314 	user_exit();
1315 
1316 	audit_syscall_exit(regs);
1317 
1318 	if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
1319 		trace_sys_exit(regs, regs_return_value(regs));
1320 
1321 	if (test_thread_flag(TIF_SYSCALL_TRACE))
1322 		tracehook_report_syscall_exit(regs, 0);
1323 
1324 	user_enter();
1325 }
1326