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1/*
2 * linux/arch/parisc/kernel/signal.c: Architecture-specific signal
3 * handling support.
4 *
5 * Copyright (C) 2000 David Huggins-Daines <dhd@debian.org>
6 * Copyright (C) 2000 Linuxcare, Inc.
7 *
8 * Based on the ia64, i386, and alpha versions.
9 *
10 * Like the IA-64, we are a recent enough port (we are *starting*
11 * with glibc2.2) that we do not need to support the old non-realtime
12 * Linux signals. Therefore we don't.
13 */
14
15#include <linux/sched.h>
16#include <linux/mm.h>
17#include <linux/smp.h>
18#include <linux/kernel.h>
19#include <linux/signal.h>
20#include <linux/errno.h>
21#include <linux/wait.h>
22#include <linux/ptrace.h>
23#include <linux/tracehook.h>
24#include <linux/unistd.h>
25#include <linux/stddef.h>
26#include <linux/compat.h>
27#include <linux/elf.h>
28#include <asm/ucontext.h>
29#include <asm/rt_sigframe.h>
30#include <asm/uaccess.h>
31#include <asm/pgalloc.h>
32#include <asm/cacheflush.h>
33#include <asm/asm-offsets.h>
34
35#ifdef CONFIG_COMPAT
36#include "signal32.h"
37#endif
38
39#define DEBUG_SIG 0
40#define DEBUG_SIG_LEVEL 2
41
42#if DEBUG_SIG
43#define DBG(LEVEL, ...) \
44 ((DEBUG_SIG_LEVEL >= LEVEL) \
45 ? printk(__VA_ARGS__) : (void) 0)
46#else
47#define DBG(LEVEL, ...)
48#endif
49
50/* gcc will complain if a pointer is cast to an integer of different
51 * size. If you really need to do this (and we do for an ELF32 user
52 * application in an ELF64 kernel) then you have to do a cast to an
53 * integer of the same size first. The A() macro accomplishes
54 * this. */
55#define A(__x) ((unsigned long)(__x))
56
57/*
58 * Do a signal return - restore sigcontext.
59 */
60
61/* Trampoline for calling rt_sigreturn() */
62#define INSN_LDI_R25_0 0x34190000 /* ldi 0,%r25 (in_syscall=0) */
63#define INSN_LDI_R25_1 0x34190002 /* ldi 1,%r25 (in_syscall=1) */
64#define INSN_LDI_R20 0x3414015a /* ldi __NR_rt_sigreturn,%r20 */
65#define INSN_BLE_SR2_R0 0xe4008200 /* be,l 0x100(%sr2,%r0),%sr0,%r31 */
66#define INSN_NOP 0x08000240 /* nop */
67/* For debugging */
68#define INSN_DIE_HORRIBLY 0x68000ccc /* stw %r0,0x666(%sr0,%r0) */
69
70static long
71restore_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs)
72{
73 long err = 0;
74
75 err |= __copy_from_user(regs->gr, sc->sc_gr, sizeof(regs->gr));
76 err |= __copy_from_user(regs->fr, sc->sc_fr, sizeof(regs->fr));
77 err |= __copy_from_user(regs->iaoq, sc->sc_iaoq, sizeof(regs->iaoq));
78 err |= __copy_from_user(regs->iasq, sc->sc_iasq, sizeof(regs->iasq));
79 err |= __get_user(regs->sar, &sc->sc_sar);
80 DBG(2,"restore_sigcontext: iaoq is %#lx / %#lx\n",
81 regs->iaoq[0],regs->iaoq[1]);
82 DBG(2,"restore_sigcontext: r28 is %ld\n", regs->gr[28]);
83 return err;
84}
85
86void
87sys_rt_sigreturn(struct pt_regs *regs, int in_syscall)
88{
89 struct rt_sigframe __user *frame;
90 sigset_t set;
91 unsigned long usp = (regs->gr[30] & ~(0x01UL));
92 unsigned long sigframe_size = PARISC_RT_SIGFRAME_SIZE;
93#ifdef CONFIG_64BIT
94 compat_sigset_t compat_set;
95 struct compat_rt_sigframe __user * compat_frame;
96
97 if (is_compat_task())
98 sigframe_size = PARISC_RT_SIGFRAME_SIZE32;
99#endif
100
101 current->restart_block.fn = do_no_restart_syscall;
102
103 /* Unwind the user stack to get the rt_sigframe structure. */
104 frame = (struct rt_sigframe __user *)
105 (usp - sigframe_size);
106 DBG(2,"sys_rt_sigreturn: frame is %p\n", frame);
107
108 regs->orig_r28 = 1; /* no restarts for sigreturn */
109
110#ifdef CONFIG_64BIT
111 compat_frame = (struct compat_rt_sigframe __user *)frame;
112
113 if (is_compat_task()) {
114 DBG(2,"sys_rt_sigreturn: ELF32 process.\n");
115 if (__copy_from_user(&compat_set, &compat_frame->uc.uc_sigmask, sizeof(compat_set)))
116 goto give_sigsegv;
117 sigset_32to64(&set,&compat_set);
118 } else
119#endif
120 {
121 if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
122 goto give_sigsegv;
123 }
124
125 set_current_blocked(&set);
126
127 /* Good thing we saved the old gr[30], eh? */
128#ifdef CONFIG_64BIT
129 if (is_compat_task()) {
130 DBG(1,"sys_rt_sigreturn: compat_frame->uc.uc_mcontext 0x%p\n",
131 &compat_frame->uc.uc_mcontext);
132// FIXME: Load upper half from register file
133 if (restore_sigcontext32(&compat_frame->uc.uc_mcontext,
134 &compat_frame->regs, regs))
135 goto give_sigsegv;
136 DBG(1,"sys_rt_sigreturn: usp %#08lx stack 0x%p\n",
137 usp, &compat_frame->uc.uc_stack);
138 if (compat_restore_altstack(&compat_frame->uc.uc_stack))
139 goto give_sigsegv;
140 } else
141#endif
142 {
143 DBG(1,"sys_rt_sigreturn: frame->uc.uc_mcontext 0x%p\n",
144 &frame->uc.uc_mcontext);
145 if (restore_sigcontext(&frame->uc.uc_mcontext, regs))
146 goto give_sigsegv;
147 DBG(1,"sys_rt_sigreturn: usp %#08lx stack 0x%p\n",
148 usp, &frame->uc.uc_stack);
149 if (restore_altstack(&frame->uc.uc_stack))
150 goto give_sigsegv;
151 }
152
153
154
155 /* If we are on the syscall path IAOQ will not be restored, and
156 * if we are on the interrupt path we must not corrupt gr31.
157 */
158 if (in_syscall)
159 regs->gr[31] = regs->iaoq[0];
160#if DEBUG_SIG
161 DBG(1,"sys_rt_sigreturn: returning to %#lx, DUMPING REGS:\n", regs->iaoq[0]);
162 show_regs(regs);
163#endif
164 return;
165
166give_sigsegv:
167 DBG(1,"sys_rt_sigreturn: Sending SIGSEGV\n");
168 force_sig(SIGSEGV, current);
169 return;
170}
171
172/*
173 * Set up a signal frame.
174 */
175
176static inline void __user *
177get_sigframe(struct k_sigaction *ka, unsigned long sp, size_t frame_size)
178{
179 /*FIXME: ELF32 vs. ELF64 has different frame_size, but since we
180 don't use the parameter it doesn't matter */
181
182 DBG(1,"get_sigframe: ka = %#lx, sp = %#lx, frame_size = %#lx\n",
183 (unsigned long)ka, sp, frame_size);
184
185 /* Align alternate stack and reserve 64 bytes for the signal
186 handler's frame marker. */
187 if ((ka->sa.sa_flags & SA_ONSTACK) != 0 && ! sas_ss_flags(sp))
188 sp = (current->sas_ss_sp + 0x7f) & ~0x3f; /* Stacks grow up! */
189
190 DBG(1,"get_sigframe: Returning sp = %#lx\n", (unsigned long)sp);
191 return (void __user *) sp; /* Stacks grow up. Fun. */
192}
193
194static long
195setup_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs, int in_syscall)
196
197{
198 unsigned long flags = 0;
199 long err = 0;
200
201 if (on_sig_stack((unsigned long) sc))
202 flags |= PARISC_SC_FLAG_ONSTACK;
203 if (in_syscall) {
204 flags |= PARISC_SC_FLAG_IN_SYSCALL;
205 /* regs->iaoq is undefined in the syscall return path */
206 err |= __put_user(regs->gr[31], &sc->sc_iaoq[0]);
207 err |= __put_user(regs->gr[31]+4, &sc->sc_iaoq[1]);
208 err |= __put_user(regs->sr[3], &sc->sc_iasq[0]);
209 err |= __put_user(regs->sr[3], &sc->sc_iasq[1]);
210 DBG(1,"setup_sigcontext: iaoq %#lx / %#lx (in syscall)\n",
211 regs->gr[31], regs->gr[31]+4);
212 } else {
213 err |= __copy_to_user(sc->sc_iaoq, regs->iaoq, sizeof(regs->iaoq));
214 err |= __copy_to_user(sc->sc_iasq, regs->iasq, sizeof(regs->iasq));
215 DBG(1,"setup_sigcontext: iaoq %#lx / %#lx (not in syscall)\n",
216 regs->iaoq[0], regs->iaoq[1]);
217 }
218
219 err |= __put_user(flags, &sc->sc_flags);
220 err |= __copy_to_user(sc->sc_gr, regs->gr, sizeof(regs->gr));
221 err |= __copy_to_user(sc->sc_fr, regs->fr, sizeof(regs->fr));
222 err |= __put_user(regs->sar, &sc->sc_sar);
223 DBG(1,"setup_sigcontext: r28 is %ld\n", regs->gr[28]);
224
225 return err;
226}
227
228static long
229setup_rt_frame(struct ksignal *ksig, sigset_t *set, struct pt_regs *regs,
230 int in_syscall)
231{
232 struct rt_sigframe __user *frame;
233 unsigned long rp, usp;
234 unsigned long haddr, sigframe_size;
235 int err = 0;
236#ifdef CONFIG_64BIT
237 struct compat_rt_sigframe __user * compat_frame;
238 compat_sigset_t compat_set;
239#endif
240
241 usp = (regs->gr[30] & ~(0x01UL));
242 /*FIXME: frame_size parameter is unused, remove it. */
243 frame = get_sigframe(&ksig->ka, usp, sizeof(*frame));
244
245 DBG(1,"SETUP_RT_FRAME: START\n");
246 DBG(1,"setup_rt_frame: frame %p info %p\n", frame, ksig->info);
247
248
249#ifdef CONFIG_64BIT
250
251 compat_frame = (struct compat_rt_sigframe __user *)frame;
252
253 if (is_compat_task()) {
254 DBG(1,"setup_rt_frame: frame->info = 0x%p\n", &compat_frame->info);
255 err |= copy_siginfo_to_user32(&compat_frame->info, &ksig->info);
256 err |= __compat_save_altstack( &compat_frame->uc.uc_stack, regs->gr[30]);
257 DBG(1,"setup_rt_frame: frame->uc = 0x%p\n", &compat_frame->uc);
258 DBG(1,"setup_rt_frame: frame->uc.uc_mcontext = 0x%p\n", &compat_frame->uc.uc_mcontext);
259 err |= setup_sigcontext32(&compat_frame->uc.uc_mcontext,
260 &compat_frame->regs, regs, in_syscall);
261 sigset_64to32(&compat_set,set);
262 err |= __copy_to_user(&compat_frame->uc.uc_sigmask, &compat_set, sizeof(compat_set));
263 } else
264#endif
265 {
266 DBG(1,"setup_rt_frame: frame->info = 0x%p\n", &frame->info);
267 err |= copy_siginfo_to_user(&frame->info, &ksig->info);
268 err |= __save_altstack(&frame->uc.uc_stack, regs->gr[30]);
269 DBG(1,"setup_rt_frame: frame->uc = 0x%p\n", &frame->uc);
270 DBG(1,"setup_rt_frame: frame->uc.uc_mcontext = 0x%p\n", &frame->uc.uc_mcontext);
271 err |= setup_sigcontext(&frame->uc.uc_mcontext, regs, in_syscall);
272 /* FIXME: Should probably be converted as well for the compat case */
273 err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
274 }
275
276 if (err)
277 return -EFAULT;
278
279 /* Set up to return from userspace. If provided, use a stub
280 already in userspace. The first words of tramp are used to
281 save the previous sigrestartblock trampoline that might be
282 on the stack. We start the sigreturn trampoline at
283 SIGRESTARTBLOCK_TRAMP+X. */
284 err |= __put_user(in_syscall ? INSN_LDI_R25_1 : INSN_LDI_R25_0,
285 &frame->tramp[SIGRESTARTBLOCK_TRAMP+0]);
286 err |= __put_user(INSN_LDI_R20,
287 &frame->tramp[SIGRESTARTBLOCK_TRAMP+1]);
288 err |= __put_user(INSN_BLE_SR2_R0,
289 &frame->tramp[SIGRESTARTBLOCK_TRAMP+2]);
290 err |= __put_user(INSN_NOP, &frame->tramp[SIGRESTARTBLOCK_TRAMP+3]);
291
292#if DEBUG_SIG
293 /* Assert that we're flushing in the correct space... */
294 {
295 unsigned long sid;
296 asm ("mfsp %%sr3,%0" : "=r" (sid));
297 DBG(1,"setup_rt_frame: Flushing 64 bytes at space %#x offset %p\n",
298 sid, frame->tramp);
299 }
300#endif
301
302 flush_user_dcache_range((unsigned long) &frame->tramp[0],
303 (unsigned long) &frame->tramp[TRAMP_SIZE]);
304 flush_user_icache_range((unsigned long) &frame->tramp[0],
305 (unsigned long) &frame->tramp[TRAMP_SIZE]);
306
307 /* TRAMP Words 0-4, Length 5 = SIGRESTARTBLOCK_TRAMP
308 * TRAMP Words 5-9, Length 4 = SIGRETURN_TRAMP
309 * So the SIGRETURN_TRAMP is at the end of SIGRESTARTBLOCK_TRAMP
310 */
311 rp = (unsigned long) &frame->tramp[SIGRESTARTBLOCK_TRAMP];
312
313 if (err)
314 return -EFAULT;
315
316 haddr = A(ksig->ka.sa.sa_handler);
317 /* The sa_handler may be a pointer to a function descriptor */
318#ifdef CONFIG_64BIT
319 if (is_compat_task()) {
320#endif
321 if (haddr & PA_PLABEL_FDESC) {
322 Elf32_Fdesc fdesc;
323 Elf32_Fdesc __user *ufdesc = (Elf32_Fdesc __user *)A(haddr & ~3);
324
325 err = __copy_from_user(&fdesc, ufdesc, sizeof(fdesc));
326
327 if (err)
328 return -EFAULT;
329
330 haddr = fdesc.addr;
331 regs->gr[19] = fdesc.gp;
332 }
333#ifdef CONFIG_64BIT
334 } else {
335 Elf64_Fdesc fdesc;
336 Elf64_Fdesc __user *ufdesc = (Elf64_Fdesc __user *)A(haddr & ~3);
337
338 err = __copy_from_user(&fdesc, ufdesc, sizeof(fdesc));
339
340 if (err)
341 return -EFAULT;
342
343 haddr = fdesc.addr;
344 regs->gr[19] = fdesc.gp;
345 DBG(1,"setup_rt_frame: 64 bit signal, exe=%#lx, r19=%#lx, in_syscall=%d\n",
346 haddr, regs->gr[19], in_syscall);
347 }
348#endif
349
350 /* The syscall return path will create IAOQ values from r31.
351 */
352 sigframe_size = PARISC_RT_SIGFRAME_SIZE;
353#ifdef CONFIG_64BIT
354 if (is_compat_task())
355 sigframe_size = PARISC_RT_SIGFRAME_SIZE32;
356#endif
357 if (in_syscall) {
358 regs->gr[31] = haddr;
359#ifdef CONFIG_64BIT
360 if (!test_thread_flag(TIF_32BIT))
361 sigframe_size |= 1;
362#endif
363 } else {
364 unsigned long psw = USER_PSW;
365#ifdef CONFIG_64BIT
366 if (!test_thread_flag(TIF_32BIT))
367 psw |= PSW_W;
368#endif
369
370 /* If we are singlestepping, arrange a trap to be delivered
371 when we return to userspace. Note the semantics -- we
372 should trap before the first insn in the handler is
373 executed. Ref:
374 http://sources.redhat.com/ml/gdb/2004-11/msg00245.html
375 */
376 if (pa_psw(current)->r) {
377 pa_psw(current)->r = 0;
378 psw |= PSW_R;
379 mtctl(-1, 0);
380 }
381
382 regs->gr[0] = psw;
383 regs->iaoq[0] = haddr | 3;
384 regs->iaoq[1] = regs->iaoq[0] + 4;
385 }
386
387 regs->gr[2] = rp; /* userland return pointer */
388 regs->gr[26] = ksig->sig; /* signal number */
389
390#ifdef CONFIG_64BIT
391 if (is_compat_task()) {
392 regs->gr[25] = A(&compat_frame->info); /* siginfo pointer */
393 regs->gr[24] = A(&compat_frame->uc); /* ucontext pointer */
394 } else
395#endif
396 {
397 regs->gr[25] = A(&frame->info); /* siginfo pointer */
398 regs->gr[24] = A(&frame->uc); /* ucontext pointer */
399 }
400
401 DBG(1,"setup_rt_frame: making sigreturn frame: %#lx + %#lx = %#lx\n",
402 regs->gr[30], sigframe_size,
403 regs->gr[30] + sigframe_size);
404 /* Raise the user stack pointer to make a proper call frame. */
405 regs->gr[30] = (A(frame) + sigframe_size);
406
407
408 DBG(1,"setup_rt_frame: sig deliver (%s,%d) frame=0x%p sp=%#lx iaoq=%#lx/%#lx rp=%#lx\n",
409 current->comm, current->pid, frame, regs->gr[30],
410 regs->iaoq[0], regs->iaoq[1], rp);
411
412 return 0;
413}
414
415/*
416 * OK, we're invoking a handler.
417 */
418
419static void
420handle_signal(struct ksignal *ksig, struct pt_regs *regs, int in_syscall)
421{
422 int ret;
423 sigset_t *oldset = sigmask_to_save();
424
425 DBG(1,"handle_signal: sig=%ld, ka=%p, info=%p, oldset=%p, regs=%p\n",
426 ksig->sig, ksig->ka, ksig->info, oldset, regs);
427
428 /* Set up the stack frame */
429 ret = setup_rt_frame(ksig, oldset, regs, in_syscall);
430
431 signal_setup_done(ret, ksig, test_thread_flag(TIF_SINGLESTEP) ||
432 test_thread_flag(TIF_BLOCKSTEP));
433
434 DBG(1,KERN_DEBUG "do_signal: Exit (success), regs->gr[28] = %ld\n",
435 regs->gr[28]);
436}
437
438/*
439 * Check how the syscall number gets loaded into %r20 within
440 * the delay branch in userspace and adjust as needed.
441 */
442
443static void check_syscallno_in_delay_branch(struct pt_regs *regs)
444{
445 u32 opcode, source_reg;
446 u32 __user *uaddr;
447 int err;
448
449 /* Usually we don't have to restore %r20 (the system call number)
450 * because it gets loaded in the delay slot of the branch external
451 * instruction via the ldi instruction.
452 * In some cases a register-to-register copy instruction might have
453 * been used instead, in which case we need to copy the syscall
454 * number into the source register before returning to userspace.
455 */
456
457 /* A syscall is just a branch, so all we have to do is fiddle the
458 * return pointer so that the ble instruction gets executed again.
459 */
460 regs->gr[31] -= 8; /* delayed branching */
461
462 /* Get assembler opcode of code in delay branch */
463 uaddr = (unsigned int *) ((regs->gr[31] & ~3) + 4);
464 err = get_user(opcode, uaddr);
465 if (err)
466 return;
467
468 /* Check if delay branch uses "ldi int,%r20" */
469 if ((opcode & 0xffff0000) == 0x34140000)
470 return; /* everything ok, just return */
471
472 /* Check if delay branch uses "nop" */
473 if (opcode == INSN_NOP)
474 return;
475
476 /* Check if delay branch uses "copy %rX,%r20" */
477 if ((opcode & 0xffe0ffff) == 0x08000254) {
478 source_reg = (opcode >> 16) & 31;
479 regs->gr[source_reg] = regs->gr[20];
480 return;
481 }
482
483 pr_warn("syscall restart: %s (pid %d): unexpected opcode 0x%08x\n",
484 current->comm, task_pid_nr(current), opcode);
485}
486
487static inline void
488syscall_restart(struct pt_regs *regs, struct k_sigaction *ka)
489{
490 if (regs->orig_r28)
491 return;
492 regs->orig_r28 = 1; /* no more restarts */
493 /* Check the return code */
494 switch (regs->gr[28]) {
495 case -ERESTART_RESTARTBLOCK:
496 case -ERESTARTNOHAND:
497 DBG(1,"ERESTARTNOHAND: returning -EINTR\n");
498 regs->gr[28] = -EINTR;
499 break;
500
501 case -ERESTARTSYS:
502 if (!(ka->sa.sa_flags & SA_RESTART)) {
503 DBG(1,"ERESTARTSYS: putting -EINTR\n");
504 regs->gr[28] = -EINTR;
505 break;
506 }
507 /* fallthrough */
508 case -ERESTARTNOINTR:
509 check_syscallno_in_delay_branch(regs);
510 break;
511 }
512}
513
514static inline void
515insert_restart_trampoline(struct pt_regs *regs)
516{
517 if (regs->orig_r28)
518 return;
519 regs->orig_r28 = 1; /* no more restarts */
520 switch(regs->gr[28]) {
521 case -ERESTART_RESTARTBLOCK: {
522 /* Restart the system call - no handlers present */
523 unsigned int *usp = (unsigned int *)regs->gr[30];
524 unsigned long start = (unsigned long) &usp[2];
525 unsigned long end = (unsigned long) &usp[5];
526 long err = 0;
527
528 /* Setup a trampoline to restart the syscall
529 * with __NR_restart_syscall
530 *
531 * 0: <return address (orig r31)>
532 * 4: <2nd half for 64-bit>
533 * 8: ldw 0(%sp), %r31
534 * 12: be 0x100(%sr2, %r0)
535 * 16: ldi __NR_restart_syscall, %r20
536 */
537#ifdef CONFIG_64BIT
538 err |= put_user(regs->gr[31] >> 32, &usp[0]);
539 err |= put_user(regs->gr[31] & 0xffffffff, &usp[1]);
540 err |= put_user(0x0fc010df, &usp[2]);
541#else
542 err |= put_user(regs->gr[31], &usp[0]);
543 err |= put_user(0x0fc0109f, &usp[2]);
544#endif
545 err |= put_user(0xe0008200, &usp[3]);
546 err |= put_user(0x34140000, &usp[4]);
547
548 WARN_ON(err);
549
550 /* flush data/instruction cache for new insns */
551 flush_user_dcache_range(start, end);
552 flush_user_icache_range(start, end);
553
554 regs->gr[31] = regs->gr[30] + 8;
555 return;
556 }
557 case -ERESTARTNOHAND:
558 case -ERESTARTSYS:
559 case -ERESTARTNOINTR:
560 check_syscallno_in_delay_branch(regs);
561 return;
562 default:
563 break;
564 }
565}
566
567/*
568 * Note that 'init' is a special process: it doesn't get signals it doesn't
569 * want to handle. Thus you cannot kill init even with a SIGKILL even by
570 * mistake.
571 *
572 * We need to be able to restore the syscall arguments (r21-r26) to
573 * restart syscalls. Thus, the syscall path should save them in the
574 * pt_regs structure (it's okay to do so since they are caller-save
575 * registers). As noted below, the syscall number gets restored for
576 * us due to the magic of delayed branching.
577 */
578asmlinkage void
579do_signal(struct pt_regs *regs, long in_syscall)
580{
581 struct ksignal ksig;
582
583 DBG(1,"\ndo_signal: regs=0x%p, sr7 %#lx, in_syscall=%d\n",
584 regs, regs->sr[7], in_syscall);
585
586 if (get_signal(&ksig)) {
587 DBG(3,"do_signal: signr = %d, regs->gr[28] = %ld\n", signr, regs->gr[28]);
588 /* Restart a system call if necessary. */
589 if (in_syscall)
590 syscall_restart(regs, &ksig.ka);
591
592 handle_signal(&ksig, regs, in_syscall);
593 return;
594 }
595
596 /* Did we come from a system call? */
597 if (in_syscall)
598 insert_restart_trampoline(regs);
599
600 DBG(1,"do_signal: Exit (not delivered), regs->gr[28] = %ld\n",
601 regs->gr[28]);
602
603 restore_saved_sigmask();
604}
605
606void do_notify_resume(struct pt_regs *regs, long in_syscall)
607{
608 if (test_thread_flag(TIF_SIGPENDING))
609 do_signal(regs, in_syscall);
610
611 if (test_thread_flag(TIF_NOTIFY_RESUME)) {
612 clear_thread_flag(TIF_NOTIFY_RESUME);
613 tracehook_notify_resume(regs);
614 }
615}
1/*
2 * linux/arch/parisc/kernel/signal.c: Architecture-specific signal
3 * handling support.
4 *
5 * Copyright (C) 2000 David Huggins-Daines <dhd@debian.org>
6 * Copyright (C) 2000 Linuxcare, Inc.
7 *
8 * Based on the ia64, i386, and alpha versions.
9 *
10 * Like the IA-64, we are a recent enough port (we are *starting*
11 * with glibc2.2) that we do not need to support the old non-realtime
12 * Linux signals. Therefore we don't. HP/UX signals will go in
13 * arch/parisc/hpux/signal.c when we figure out how to do them.
14 */
15
16#include <linux/sched.h>
17#include <linux/mm.h>
18#include <linux/smp.h>
19#include <linux/kernel.h>
20#include <linux/signal.h>
21#include <linux/errno.h>
22#include <linux/wait.h>
23#include <linux/ptrace.h>
24#include <linux/tracehook.h>
25#include <linux/unistd.h>
26#include <linux/stddef.h>
27#include <linux/compat.h>
28#include <linux/elf.h>
29#include <asm/ucontext.h>
30#include <asm/rt_sigframe.h>
31#include <asm/uaccess.h>
32#include <asm/pgalloc.h>
33#include <asm/cacheflush.h>
34#include <asm/asm-offsets.h>
35
36#ifdef CONFIG_COMPAT
37#include "signal32.h"
38#endif
39
40#define DEBUG_SIG 0
41#define DEBUG_SIG_LEVEL 2
42
43#if DEBUG_SIG
44#define DBG(LEVEL, ...) \
45 ((DEBUG_SIG_LEVEL >= LEVEL) \
46 ? printk(__VA_ARGS__) : (void) 0)
47#else
48#define DBG(LEVEL, ...)
49#endif
50
51/* gcc will complain if a pointer is cast to an integer of different
52 * size. If you really need to do this (and we do for an ELF32 user
53 * application in an ELF64 kernel) then you have to do a cast to an
54 * integer of the same size first. The A() macro accomplishes
55 * this. */
56#define A(__x) ((unsigned long)(__x))
57
58/*
59 * Do a signal return - restore sigcontext.
60 */
61
62/* Trampoline for calling rt_sigreturn() */
63#define INSN_LDI_R25_0 0x34190000 /* ldi 0,%r25 (in_syscall=0) */
64#define INSN_LDI_R25_1 0x34190002 /* ldi 1,%r25 (in_syscall=1) */
65#define INSN_LDI_R20 0x3414015a /* ldi __NR_rt_sigreturn,%r20 */
66#define INSN_BLE_SR2_R0 0xe4008200 /* be,l 0x100(%sr2,%r0),%sr0,%r31 */
67#define INSN_NOP 0x08000240 /* nop */
68/* For debugging */
69#define INSN_DIE_HORRIBLY 0x68000ccc /* stw %r0,0x666(%sr0,%r0) */
70
71static long
72restore_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs)
73{
74 long err = 0;
75
76 err |= __copy_from_user(regs->gr, sc->sc_gr, sizeof(regs->gr));
77 err |= __copy_from_user(regs->fr, sc->sc_fr, sizeof(regs->fr));
78 err |= __copy_from_user(regs->iaoq, sc->sc_iaoq, sizeof(regs->iaoq));
79 err |= __copy_from_user(regs->iasq, sc->sc_iasq, sizeof(regs->iasq));
80 err |= __get_user(regs->sar, &sc->sc_sar);
81 DBG(2,"restore_sigcontext: iaoq is %#lx / %#lx\n",
82 regs->iaoq[0],regs->iaoq[1]);
83 DBG(2,"restore_sigcontext: r28 is %ld\n", regs->gr[28]);
84 return err;
85}
86
87void
88sys_rt_sigreturn(struct pt_regs *regs, int in_syscall)
89{
90 struct rt_sigframe __user *frame;
91 sigset_t set;
92 unsigned long usp = (regs->gr[30] & ~(0x01UL));
93 unsigned long sigframe_size = PARISC_RT_SIGFRAME_SIZE;
94#ifdef CONFIG_64BIT
95 compat_sigset_t compat_set;
96 struct compat_rt_sigframe __user * compat_frame;
97
98 if (is_compat_task())
99 sigframe_size = PARISC_RT_SIGFRAME_SIZE32;
100#endif
101
102 current_thread_info()->restart_block.fn = do_no_restart_syscall;
103
104 /* Unwind the user stack to get the rt_sigframe structure. */
105 frame = (struct rt_sigframe __user *)
106 (usp - sigframe_size);
107 DBG(2,"sys_rt_sigreturn: frame is %p\n", frame);
108
109 regs->orig_r28 = 1; /* no restarts for sigreturn */
110
111#ifdef CONFIG_64BIT
112 compat_frame = (struct compat_rt_sigframe __user *)frame;
113
114 if (is_compat_task()) {
115 DBG(2,"sys_rt_sigreturn: ELF32 process.\n");
116 if (__copy_from_user(&compat_set, &compat_frame->uc.uc_sigmask, sizeof(compat_set)))
117 goto give_sigsegv;
118 sigset_32to64(&set,&compat_set);
119 } else
120#endif
121 {
122 if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
123 goto give_sigsegv;
124 }
125
126 set_current_blocked(&set);
127
128 /* Good thing we saved the old gr[30], eh? */
129#ifdef CONFIG_64BIT
130 if (is_compat_task()) {
131 DBG(1,"sys_rt_sigreturn: compat_frame->uc.uc_mcontext 0x%p\n",
132 &compat_frame->uc.uc_mcontext);
133// FIXME: Load upper half from register file
134 if (restore_sigcontext32(&compat_frame->uc.uc_mcontext,
135 &compat_frame->regs, regs))
136 goto give_sigsegv;
137 DBG(1,"sys_rt_sigreturn: usp %#08lx stack 0x%p\n",
138 usp, &compat_frame->uc.uc_stack);
139 if (compat_restore_altstack(&compat_frame->uc.uc_stack))
140 goto give_sigsegv;
141 } else
142#endif
143 {
144 DBG(1,"sys_rt_sigreturn: frame->uc.uc_mcontext 0x%p\n",
145 &frame->uc.uc_mcontext);
146 if (restore_sigcontext(&frame->uc.uc_mcontext, regs))
147 goto give_sigsegv;
148 DBG(1,"sys_rt_sigreturn: usp %#08lx stack 0x%p\n",
149 usp, &frame->uc.uc_stack);
150 if (restore_altstack(&frame->uc.uc_stack))
151 goto give_sigsegv;
152 }
153
154
155
156 /* If we are on the syscall path IAOQ will not be restored, and
157 * if we are on the interrupt path we must not corrupt gr31.
158 */
159 if (in_syscall)
160 regs->gr[31] = regs->iaoq[0];
161#if DEBUG_SIG
162 DBG(1,"sys_rt_sigreturn: returning to %#lx, DUMPING REGS:\n", regs->iaoq[0]);
163 show_regs(regs);
164#endif
165 return;
166
167give_sigsegv:
168 DBG(1,"sys_rt_sigreturn: Sending SIGSEGV\n");
169 force_sig(SIGSEGV, current);
170 return;
171}
172
173/*
174 * Set up a signal frame.
175 */
176
177static inline void __user *
178get_sigframe(struct k_sigaction *ka, unsigned long sp, size_t frame_size)
179{
180 /*FIXME: ELF32 vs. ELF64 has different frame_size, but since we
181 don't use the parameter it doesn't matter */
182
183 DBG(1,"get_sigframe: ka = %#lx, sp = %#lx, frame_size = %#lx\n",
184 (unsigned long)ka, sp, frame_size);
185
186 /* Align alternate stack and reserve 64 bytes for the signal
187 handler's frame marker. */
188 if ((ka->sa.sa_flags & SA_ONSTACK) != 0 && ! sas_ss_flags(sp))
189 sp = (current->sas_ss_sp + 0x7f) & ~0x3f; /* Stacks grow up! */
190
191 DBG(1,"get_sigframe: Returning sp = %#lx\n", (unsigned long)sp);
192 return (void __user *) sp; /* Stacks grow up. Fun. */
193}
194
195static long
196setup_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs, int in_syscall)
197
198{
199 unsigned long flags = 0;
200 long err = 0;
201
202 if (on_sig_stack((unsigned long) sc))
203 flags |= PARISC_SC_FLAG_ONSTACK;
204 if (in_syscall) {
205 flags |= PARISC_SC_FLAG_IN_SYSCALL;
206 /* regs->iaoq is undefined in the syscall return path */
207 err |= __put_user(regs->gr[31], &sc->sc_iaoq[0]);
208 err |= __put_user(regs->gr[31]+4, &sc->sc_iaoq[1]);
209 err |= __put_user(regs->sr[3], &sc->sc_iasq[0]);
210 err |= __put_user(regs->sr[3], &sc->sc_iasq[1]);
211 DBG(1,"setup_sigcontext: iaoq %#lx / %#lx (in syscall)\n",
212 regs->gr[31], regs->gr[31]+4);
213 } else {
214 err |= __copy_to_user(sc->sc_iaoq, regs->iaoq, sizeof(regs->iaoq));
215 err |= __copy_to_user(sc->sc_iasq, regs->iasq, sizeof(regs->iasq));
216 DBG(1,"setup_sigcontext: iaoq %#lx / %#lx (not in syscall)\n",
217 regs->iaoq[0], regs->iaoq[1]);
218 }
219
220 err |= __put_user(flags, &sc->sc_flags);
221 err |= __copy_to_user(sc->sc_gr, regs->gr, sizeof(regs->gr));
222 err |= __copy_to_user(sc->sc_fr, regs->fr, sizeof(regs->fr));
223 err |= __put_user(regs->sar, &sc->sc_sar);
224 DBG(1,"setup_sigcontext: r28 is %ld\n", regs->gr[28]);
225
226 return err;
227}
228
229static long
230setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
231 sigset_t *set, struct pt_regs *regs, int in_syscall)
232{
233 struct rt_sigframe __user *frame;
234 unsigned long rp, usp;
235 unsigned long haddr, sigframe_size;
236 int err = 0;
237#ifdef CONFIG_64BIT
238 struct compat_rt_sigframe __user * compat_frame;
239 compat_sigset_t compat_set;
240#endif
241
242 usp = (regs->gr[30] & ~(0x01UL));
243 /*FIXME: frame_size parameter is unused, remove it. */
244 frame = get_sigframe(ka, usp, sizeof(*frame));
245
246 DBG(1,"SETUP_RT_FRAME: START\n");
247 DBG(1,"setup_rt_frame: frame %p info %p\n", frame, info);
248
249
250#ifdef CONFIG_64BIT
251
252 compat_frame = (struct compat_rt_sigframe __user *)frame;
253
254 if (is_compat_task()) {
255 DBG(1,"setup_rt_frame: frame->info = 0x%p\n", &compat_frame->info);
256 err |= copy_siginfo_to_user32(&compat_frame->info, info);
257 err |= __compat_save_altstack( &compat_frame->uc.uc_stack, regs->gr[30]);
258 DBG(1,"setup_rt_frame: frame->uc = 0x%p\n", &compat_frame->uc);
259 DBG(1,"setup_rt_frame: frame->uc.uc_mcontext = 0x%p\n", &compat_frame->uc.uc_mcontext);
260 err |= setup_sigcontext32(&compat_frame->uc.uc_mcontext,
261 &compat_frame->regs, regs, in_syscall);
262 sigset_64to32(&compat_set,set);
263 err |= __copy_to_user(&compat_frame->uc.uc_sigmask, &compat_set, sizeof(compat_set));
264 } else
265#endif
266 {
267 DBG(1,"setup_rt_frame: frame->info = 0x%p\n", &frame->info);
268 err |= copy_siginfo_to_user(&frame->info, info);
269 err |= __save_altstack(&frame->uc.uc_stack, regs->gr[30]);
270 DBG(1,"setup_rt_frame: frame->uc = 0x%p\n", &frame->uc);
271 DBG(1,"setup_rt_frame: frame->uc.uc_mcontext = 0x%p\n", &frame->uc.uc_mcontext);
272 err |= setup_sigcontext(&frame->uc.uc_mcontext, regs, in_syscall);
273 /* FIXME: Should probably be converted as well for the compat case */
274 err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
275 }
276
277 if (err)
278 goto give_sigsegv;
279
280 /* Set up to return from userspace. If provided, use a stub
281 already in userspace. The first words of tramp are used to
282 save the previous sigrestartblock trampoline that might be
283 on the stack. We start the sigreturn trampoline at
284 SIGRESTARTBLOCK_TRAMP+X. */
285 err |= __put_user(in_syscall ? INSN_LDI_R25_1 : INSN_LDI_R25_0,
286 &frame->tramp[SIGRESTARTBLOCK_TRAMP+0]);
287 err |= __put_user(INSN_LDI_R20,
288 &frame->tramp[SIGRESTARTBLOCK_TRAMP+1]);
289 err |= __put_user(INSN_BLE_SR2_R0,
290 &frame->tramp[SIGRESTARTBLOCK_TRAMP+2]);
291 err |= __put_user(INSN_NOP, &frame->tramp[SIGRESTARTBLOCK_TRAMP+3]);
292
293#if DEBUG_SIG
294 /* Assert that we're flushing in the correct space... */
295 {
296 unsigned long sid;
297 asm ("mfsp %%sr3,%0" : "=r" (sid));
298 DBG(1,"setup_rt_frame: Flushing 64 bytes at space %#x offset %p\n",
299 sid, frame->tramp);
300 }
301#endif
302
303 flush_user_dcache_range((unsigned long) &frame->tramp[0],
304 (unsigned long) &frame->tramp[TRAMP_SIZE]);
305 flush_user_icache_range((unsigned long) &frame->tramp[0],
306 (unsigned long) &frame->tramp[TRAMP_SIZE]);
307
308 /* TRAMP Words 0-4, Length 5 = SIGRESTARTBLOCK_TRAMP
309 * TRAMP Words 5-9, Length 4 = SIGRETURN_TRAMP
310 * So the SIGRETURN_TRAMP is at the end of SIGRESTARTBLOCK_TRAMP
311 */
312 rp = (unsigned long) &frame->tramp[SIGRESTARTBLOCK_TRAMP];
313
314 if (err)
315 goto give_sigsegv;
316
317 haddr = A(ka->sa.sa_handler);
318 /* The sa_handler may be a pointer to a function descriptor */
319#ifdef CONFIG_64BIT
320 if (is_compat_task()) {
321#endif
322 if (haddr & PA_PLABEL_FDESC) {
323 Elf32_Fdesc fdesc;
324 Elf32_Fdesc __user *ufdesc = (Elf32_Fdesc __user *)A(haddr & ~3);
325
326 err = __copy_from_user(&fdesc, ufdesc, sizeof(fdesc));
327
328 if (err)
329 goto give_sigsegv;
330
331 haddr = fdesc.addr;
332 regs->gr[19] = fdesc.gp;
333 }
334#ifdef CONFIG_64BIT
335 } else {
336 Elf64_Fdesc fdesc;
337 Elf64_Fdesc __user *ufdesc = (Elf64_Fdesc __user *)A(haddr & ~3);
338
339 err = __copy_from_user(&fdesc, ufdesc, sizeof(fdesc));
340
341 if (err)
342 goto give_sigsegv;
343
344 haddr = fdesc.addr;
345 regs->gr[19] = fdesc.gp;
346 DBG(1,"setup_rt_frame: 64 bit signal, exe=%#lx, r19=%#lx, in_syscall=%d\n",
347 haddr, regs->gr[19], in_syscall);
348 }
349#endif
350
351 /* The syscall return path will create IAOQ values from r31.
352 */
353 sigframe_size = PARISC_RT_SIGFRAME_SIZE;
354#ifdef CONFIG_64BIT
355 if (is_compat_task())
356 sigframe_size = PARISC_RT_SIGFRAME_SIZE32;
357#endif
358 if (in_syscall) {
359 regs->gr[31] = haddr;
360#ifdef CONFIG_64BIT
361 if (!test_thread_flag(TIF_32BIT))
362 sigframe_size |= 1;
363#endif
364 } else {
365 unsigned long psw = USER_PSW;
366#ifdef CONFIG_64BIT
367 if (!test_thread_flag(TIF_32BIT))
368 psw |= PSW_W;
369#endif
370
371 /* If we are singlestepping, arrange a trap to be delivered
372 when we return to userspace. Note the semantics -- we
373 should trap before the first insn in the handler is
374 executed. Ref:
375 http://sources.redhat.com/ml/gdb/2004-11/msg00245.html
376 */
377 if (pa_psw(current)->r) {
378 pa_psw(current)->r = 0;
379 psw |= PSW_R;
380 mtctl(-1, 0);
381 }
382
383 regs->gr[0] = psw;
384 regs->iaoq[0] = haddr | 3;
385 regs->iaoq[1] = regs->iaoq[0] + 4;
386 }
387
388 regs->gr[2] = rp; /* userland return pointer */
389 regs->gr[26] = sig; /* signal number */
390
391#ifdef CONFIG_64BIT
392 if (is_compat_task()) {
393 regs->gr[25] = A(&compat_frame->info); /* siginfo pointer */
394 regs->gr[24] = A(&compat_frame->uc); /* ucontext pointer */
395 } else
396#endif
397 {
398 regs->gr[25] = A(&frame->info); /* siginfo pointer */
399 regs->gr[24] = A(&frame->uc); /* ucontext pointer */
400 }
401
402 DBG(1,"setup_rt_frame: making sigreturn frame: %#lx + %#lx = %#lx\n",
403 regs->gr[30], sigframe_size,
404 regs->gr[30] + sigframe_size);
405 /* Raise the user stack pointer to make a proper call frame. */
406 regs->gr[30] = (A(frame) + sigframe_size);
407
408
409 DBG(1,"setup_rt_frame: sig deliver (%s,%d) frame=0x%p sp=%#lx iaoq=%#lx/%#lx rp=%#lx\n",
410 current->comm, current->pid, frame, regs->gr[30],
411 regs->iaoq[0], regs->iaoq[1], rp);
412
413 return 1;
414
415give_sigsegv:
416 DBG(1,"setup_rt_frame: sending SIGSEGV\n");
417 force_sigsegv(sig, current);
418 return 0;
419}
420
421/*
422 * OK, we're invoking a handler.
423 */
424
425static void
426handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka,
427 struct pt_regs *regs, int in_syscall)
428{
429 sigset_t *oldset = sigmask_to_save();
430 DBG(1,"handle_signal: sig=%ld, ka=%p, info=%p, oldset=%p, regs=%p\n",
431 sig, ka, info, oldset, regs);
432
433 /* Set up the stack frame */
434 if (!setup_rt_frame(sig, ka, info, oldset, regs, in_syscall))
435 return;
436
437 signal_delivered(sig, info, ka, regs,
438 test_thread_flag(TIF_SINGLESTEP) ||
439 test_thread_flag(TIF_BLOCKSTEP));
440
441 DBG(1,KERN_DEBUG "do_signal: Exit (success), regs->gr[28] = %ld\n",
442 regs->gr[28]);
443}
444
445static inline void
446syscall_restart(struct pt_regs *regs, struct k_sigaction *ka)
447{
448 if (regs->orig_r28)
449 return;
450 regs->orig_r28 = 1; /* no more restarts */
451 /* Check the return code */
452 switch (regs->gr[28]) {
453 case -ERESTART_RESTARTBLOCK:
454 case -ERESTARTNOHAND:
455 DBG(1,"ERESTARTNOHAND: returning -EINTR\n");
456 regs->gr[28] = -EINTR;
457 break;
458
459 case -ERESTARTSYS:
460 if (!(ka->sa.sa_flags & SA_RESTART)) {
461 DBG(1,"ERESTARTSYS: putting -EINTR\n");
462 regs->gr[28] = -EINTR;
463 break;
464 }
465 /* fallthrough */
466 case -ERESTARTNOINTR:
467 /* A syscall is just a branch, so all
468 * we have to do is fiddle the return pointer.
469 */
470 regs->gr[31] -= 8; /* delayed branching */
471 break;
472 }
473}
474
475static inline void
476insert_restart_trampoline(struct pt_regs *regs)
477{
478 if (regs->orig_r28)
479 return;
480 regs->orig_r28 = 1; /* no more restarts */
481 switch(regs->gr[28]) {
482 case -ERESTART_RESTARTBLOCK: {
483 /* Restart the system call - no handlers present */
484 unsigned int *usp = (unsigned int *)regs->gr[30];
485
486 /* Setup a trampoline to restart the syscall
487 * with __NR_restart_syscall
488 *
489 * 0: <return address (orig r31)>
490 * 4: <2nd half for 64-bit>
491 * 8: ldw 0(%sp), %r31
492 * 12: be 0x100(%sr2, %r0)
493 * 16: ldi __NR_restart_syscall, %r20
494 */
495#ifdef CONFIG_64BIT
496 put_user(regs->gr[31] >> 32, &usp[0]);
497 put_user(regs->gr[31] & 0xffffffff, &usp[1]);
498 put_user(0x0fc010df, &usp[2]);
499#else
500 put_user(regs->gr[31], &usp[0]);
501 put_user(0x0fc0109f, &usp[2]);
502#endif
503 put_user(0xe0008200, &usp[3]);
504 put_user(0x34140000, &usp[4]);
505
506 /* Stack is 64-byte aligned, and we only need
507 * to flush 1 cache line.
508 * Flushing one cacheline is cheap.
509 * "sync" on bigger (> 4 way) boxes is not.
510 */
511 flush_user_dcache_range(regs->gr[30], regs->gr[30] + 4);
512 flush_user_icache_range(regs->gr[30], regs->gr[30] + 4);
513
514 regs->gr[31] = regs->gr[30] + 8;
515 return;
516 }
517 case -ERESTARTNOHAND:
518 case -ERESTARTSYS:
519 case -ERESTARTNOINTR: {
520 /* Hooray for delayed branching. We don't
521 * have to restore %r20 (the system call
522 * number) because it gets loaded in the delay
523 * slot of the branch external instruction.
524 */
525 regs->gr[31] -= 8;
526 return;
527 }
528 default:
529 break;
530 }
531}
532
533/*
534 * Note that 'init' is a special process: it doesn't get signals it doesn't
535 * want to handle. Thus you cannot kill init even with a SIGKILL even by
536 * mistake.
537 *
538 * We need to be able to restore the syscall arguments (r21-r26) to
539 * restart syscalls. Thus, the syscall path should save them in the
540 * pt_regs structure (it's okay to do so since they are caller-save
541 * registers). As noted below, the syscall number gets restored for
542 * us due to the magic of delayed branching.
543 */
544asmlinkage void
545do_signal(struct pt_regs *regs, long in_syscall)
546{
547 siginfo_t info;
548 struct k_sigaction ka;
549 int signr;
550
551 DBG(1,"\ndo_signal: regs=0x%p, sr7 %#lx, in_syscall=%d\n",
552 regs, regs->sr[7], in_syscall);
553
554 signr = get_signal_to_deliver(&info, &ka, regs, NULL);
555 DBG(3,"do_signal: signr = %d, regs->gr[28] = %ld\n", signr, regs->gr[28]);
556
557 if (signr > 0) {
558 /* Restart a system call if necessary. */
559 if (in_syscall)
560 syscall_restart(regs, &ka);
561
562 handle_signal(signr, &info, &ka, regs, in_syscall);
563 return;
564 }
565
566 /* Did we come from a system call? */
567 if (in_syscall)
568 insert_restart_trampoline(regs);
569
570 DBG(1,"do_signal: Exit (not delivered), regs->gr[28] = %ld\n",
571 regs->gr[28]);
572
573 restore_saved_sigmask();
574}
575
576void do_notify_resume(struct pt_regs *regs, long in_syscall)
577{
578 if (test_thread_flag(TIF_SIGPENDING))
579 do_signal(regs, in_syscall);
580
581 if (test_thread_flag(TIF_NOTIFY_RESUME)) {
582 clear_thread_flag(TIF_NOTIFY_RESUME);
583 tracehook_notify_resume(regs);
584 }
585}