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TOMOYO Linux Cross Reference
Linux/arch/mips/kernel/signal.c

Version: ~ [ linux-6.0 ] ~ [ linux-5.19.12 ] ~ [ linux-5.18.19 ] ~ [ linux-5.17.15 ] ~ [ linux-5.16.20 ] ~ [ linux-5.15.71 ] ~ [ linux-5.14.21 ] ~ [ linux-5.13.19 ] ~ [ linux-5.12.19 ] ~ [ linux-5.11.22 ] ~ [ linux-5.10.146 ] ~ [ linux-5.9.16 ] ~ [ linux-5.8.18 ] ~ [ linux-5.7.19 ] ~ [ linux-5.6.19 ] ~ [ linux-5.5.19 ] ~ [ linux-5.4.215 ] ~ [ linux-5.3.18 ] ~ [ linux-5.2.21 ] ~ [ linux-5.1.21 ] ~ [ linux-5.0.21 ] ~ [ linux-4.20.17 ] ~ [ linux-4.19.260 ] ~ [ linux-4.18.20 ] ~ [ linux-4.17.19 ] ~ [ linux-4.16.18 ] ~ [ linux-4.15.18 ] ~ [ linux-4.14.295 ] ~ [ linux-4.13.16 ] ~ [ linux-4.12.14 ] ~ [ linux-4.11.12 ] ~ [ linux-4.10.17 ] ~ [ linux-4.9.330 ] ~ [ linux-4.8.17 ] ~ [ linux-4.7.10 ] ~ [ linux-4.6.7 ] ~ [ linux-4.5.7 ] ~ [ linux-4.4.302 ] ~ [ linux-4.3.6 ] ~ [ linux-4.2.8 ] ~ [ linux-4.1.52 ] ~ [ linux-4.0.9 ] ~ [ linux-3.10.108 ] ~ [ linux-2.6.32.71 ] ~ [ linux-2.6.0 ] ~ [ linux-2.4.37.11 ] ~ [ unix-v6-master ] ~ [ ccs-tools-1.8.9 ] ~ [ policy-sample ] ~
Architecture: ~ [ i386 ] ~ [ alpha ] ~ [ m68k ] ~ [ mips ] ~ [ ppc ] ~ [ sparc ] ~ [ sparc64 ] ~

  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) 1991, 1992  Linus Torvalds
  7  * Copyright (C) 1994 - 2000  Ralf Baechle
  8  * Copyright (C) 1999, 2000 Silicon Graphics, Inc.
  9  * Copyright (C) 2014, Imagination Technologies Ltd.
 10  */
 11 #include <linux/cache.h>
 12 #include <linux/context_tracking.h>
 13 #include <linux/irqflags.h>
 14 #include <linux/sched.h>
 15 #include <linux/mm.h>
 16 #include <linux/personality.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/unistd.h>
 24 #include <linux/compiler.h>
 25 #include <linux/syscalls.h>
 26 #include <linux/uaccess.h>
 27 #include <linux/tracehook.h>
 28 
 29 #include <asm/abi.h>
 30 #include <asm/asm.h>
 31 #include <linux/bitops.h>
 32 #include <asm/cacheflush.h>
 33 #include <asm/fpu.h>
 34 #include <asm/sim.h>
 35 #include <asm/ucontext.h>
 36 #include <asm/cpu-features.h>
 37 #include <asm/war.h>
 38 #include <asm/vdso.h>
 39 #include <asm/dsp.h>
 40 #include <asm/inst.h>
 41 
 42 #include "signal-common.h"
 43 
 44 static int (*save_fp_context)(struct sigcontext __user *sc);
 45 static int (*restore_fp_context)(struct sigcontext __user *sc);
 46 
 47 extern asmlinkage int _save_fp_context(struct sigcontext __user *sc);
 48 extern asmlinkage int _restore_fp_context(struct sigcontext __user *sc);
 49 
 50 struct sigframe {
 51         u32 sf_ass[4];          /* argument save space for o32 */
 52         u32 sf_pad[2];          /* Was: signal trampoline */
 53         struct sigcontext sf_sc;
 54         sigset_t sf_mask;
 55 };
 56 
 57 struct rt_sigframe {
 58         u32 rs_ass[4];          /* argument save space for o32 */
 59         u32 rs_pad[2];          /* Was: signal trampoline */
 60         struct siginfo rs_info;
 61         struct ucontext rs_uc;
 62 };
 63 
 64 /*
 65  * Thread saved context copy to/from a signal context presumed to be on the
 66  * user stack, and therefore accessed with appropriate macros from uaccess.h.
 67  */
 68 static int copy_fp_to_sigcontext(struct sigcontext __user *sc)
 69 {
 70         int i;
 71         int err = 0;
 72 
 73         for (i = 0; i < NUM_FPU_REGS; i++) {
 74                 err |=
 75                     __put_user(get_fpr64(&current->thread.fpu.fpr[i], 0),
 76                                &sc->sc_fpregs[i]);
 77         }
 78         err |= __put_user(current->thread.fpu.fcr31, &sc->sc_fpc_csr);
 79 
 80         return err;
 81 }
 82 
 83 static int copy_fp_from_sigcontext(struct sigcontext __user *sc)
 84 {
 85         int i;
 86         int err = 0;
 87         u64 fpr_val;
 88 
 89         for (i = 0; i < NUM_FPU_REGS; i++) {
 90                 err |= __get_user(fpr_val, &sc->sc_fpregs[i]);
 91                 set_fpr64(&current->thread.fpu.fpr[i], 0, fpr_val);
 92         }
 93         err |= __get_user(current->thread.fpu.fcr31, &sc->sc_fpc_csr);
 94 
 95         return err;
 96 }
 97 
 98 /*
 99  * Helper routines
100  */
101 static int protected_save_fp_context(struct sigcontext __user *sc)
102 {
103         int err;
104 #ifndef CONFIG_EVA
105         while (1) {
106                 lock_fpu_owner();
107                 if (is_fpu_owner()) {
108                         err = save_fp_context(sc);
109                         unlock_fpu_owner();
110                 } else {
111                         unlock_fpu_owner();
112                         err = copy_fp_to_sigcontext(sc);
113                 }
114                 if (likely(!err))
115                         break;
116                 /* touch the sigcontext and try again */
117                 err = __put_user(0, &sc->sc_fpregs[0]) |
118                         __put_user(0, &sc->sc_fpregs[31]) |
119                         __put_user(0, &sc->sc_fpc_csr);
120                 if (err)
121                         break;  /* really bad sigcontext */
122         }
123 #else
124         /*
125          * EVA does not have FPU EVA instructions so saving fpu context directly
126          * does not work.
127          */
128         lose_fpu(1);
129         err = save_fp_context(sc); /* this might fail */
130 #endif
131         return err;
132 }
133 
134 static int protected_restore_fp_context(struct sigcontext __user *sc)
135 {
136         int err, tmp __maybe_unused;
137 #ifndef CONFIG_EVA
138         while (1) {
139                 lock_fpu_owner();
140                 if (is_fpu_owner()) {
141                         err = restore_fp_context(sc);
142                         unlock_fpu_owner();
143                 } else {
144                         unlock_fpu_owner();
145                         err = copy_fp_from_sigcontext(sc);
146                 }
147                 if (likely(!err))
148                         break;
149                 /* touch the sigcontext and try again */
150                 err = __get_user(tmp, &sc->sc_fpregs[0]) |
151                         __get_user(tmp, &sc->sc_fpregs[31]) |
152                         __get_user(tmp, &sc->sc_fpc_csr);
153                 if (err)
154                         break;  /* really bad sigcontext */
155         }
156 #else
157         /*
158          * EVA does not have FPU EVA instructions so restoring fpu context
159          * directly does not work.
160          */
161         lose_fpu(0);
162         err = restore_fp_context(sc); /* this might fail */
163 #endif
164         return err;
165 }
166 
167 int setup_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc)
168 {
169         int err = 0;
170         int i;
171         unsigned int used_math;
172 
173         err |= __put_user(regs->cp0_epc, &sc->sc_pc);
174 
175         err |= __put_user(0, &sc->sc_regs[0]);
176         for (i = 1; i < 32; i++)
177                 err |= __put_user(regs->regs[i], &sc->sc_regs[i]);
178 
179 #ifdef CONFIG_CPU_HAS_SMARTMIPS
180         err |= __put_user(regs->acx, &sc->sc_acx);
181 #endif
182         err |= __put_user(regs->hi, &sc->sc_mdhi);
183         err |= __put_user(regs->lo, &sc->sc_mdlo);
184         if (cpu_has_dsp) {
185                 err |= __put_user(mfhi1(), &sc->sc_hi1);
186                 err |= __put_user(mflo1(), &sc->sc_lo1);
187                 err |= __put_user(mfhi2(), &sc->sc_hi2);
188                 err |= __put_user(mflo2(), &sc->sc_lo2);
189                 err |= __put_user(mfhi3(), &sc->sc_hi3);
190                 err |= __put_user(mflo3(), &sc->sc_lo3);
191                 err |= __put_user(rddsp(DSP_MASK), &sc->sc_dsp);
192         }
193 
194         used_math = !!used_math();
195         err |= __put_user(used_math, &sc->sc_used_math);
196 
197         if (used_math) {
198                 /*
199                  * Save FPU state to signal context. Signal handler
200                  * will "inherit" current FPU state.
201                  */
202                 err |= protected_save_fp_context(sc);
203         }
204         return err;
205 }
206 
207 int fpcsr_pending(unsigned int __user *fpcsr)
208 {
209         int err, sig = 0;
210         unsigned int csr, enabled;
211 
212         err = __get_user(csr, fpcsr);
213         enabled = FPU_CSR_UNI_X | ((csr & FPU_CSR_ALL_E) << 5);
214         /*
215          * If the signal handler set some FPU exceptions, clear it and
216          * send SIGFPE.
217          */
218         if (csr & enabled) {
219                 csr &= ~enabled;
220                 err |= __put_user(csr, fpcsr);
221                 sig = SIGFPE;
222         }
223         return err ?: sig;
224 }
225 
226 static int
227 check_and_restore_fp_context(struct sigcontext __user *sc)
228 {
229         int err, sig;
230 
231         err = sig = fpcsr_pending(&sc->sc_fpc_csr);
232         if (err > 0)
233                 err = 0;
234         err |= protected_restore_fp_context(sc);
235         return err ?: sig;
236 }
237 
238 int restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc)
239 {
240         unsigned int used_math;
241         unsigned long treg;
242         int err = 0;
243         int i;
244 
245         /* Always make any pending restarted system calls return -EINTR */
246         current->restart_block.fn = do_no_restart_syscall;
247 
248         err |= __get_user(regs->cp0_epc, &sc->sc_pc);
249 
250 #ifdef CONFIG_CPU_HAS_SMARTMIPS
251         err |= __get_user(regs->acx, &sc->sc_acx);
252 #endif
253         err |= __get_user(regs->hi, &sc->sc_mdhi);
254         err |= __get_user(regs->lo, &sc->sc_mdlo);
255         if (cpu_has_dsp) {
256                 err |= __get_user(treg, &sc->sc_hi1); mthi1(treg);
257                 err |= __get_user(treg, &sc->sc_lo1); mtlo1(treg);
258                 err |= __get_user(treg, &sc->sc_hi2); mthi2(treg);
259                 err |= __get_user(treg, &sc->sc_lo2); mtlo2(treg);
260                 err |= __get_user(treg, &sc->sc_hi3); mthi3(treg);
261                 err |= __get_user(treg, &sc->sc_lo3); mtlo3(treg);
262                 err |= __get_user(treg, &sc->sc_dsp); wrdsp(treg, DSP_MASK);
263         }
264 
265         for (i = 1; i < 32; i++)
266                 err |= __get_user(regs->regs[i], &sc->sc_regs[i]);
267 
268         err |= __get_user(used_math, &sc->sc_used_math);
269         conditional_used_math(used_math);
270 
271         if (used_math) {
272                 /* restore fpu context if we have used it before */
273                 if (!err)
274                         err = check_and_restore_fp_context(sc);
275         } else {
276                 /* signal handler may have used FPU.  Give it up. */
277                 lose_fpu(0);
278         }
279 
280         return err;
281 }
282 
283 void __user *get_sigframe(struct ksignal *ksig, struct pt_regs *regs,
284                           size_t frame_size)
285 {
286         unsigned long sp;
287 
288         /* Default to using normal stack */
289         sp = regs->regs[29];
290 
291         /*
292          * FPU emulator may have it's own trampoline active just
293          * above the user stack, 16-bytes before the next lowest
294          * 16 byte boundary.  Try to avoid trashing it.
295          */
296         sp -= 32;
297 
298         sp = sigsp(sp, ksig);
299 
300         return (void __user *)((sp - frame_size) & (ICACHE_REFILLS_WORKAROUND_WAR ? ~(cpu_icache_line_size()-1) : ALMASK));
301 }
302 
303 /*
304  * Atomically swap in the new signal mask, and wait for a signal.
305  */
306 
307 #ifdef CONFIG_TRAD_SIGNALS
308 SYSCALL_DEFINE1(sigsuspend, sigset_t __user *, uset)
309 {
310         return sys_rt_sigsuspend(uset, sizeof(sigset_t));
311 }
312 #endif
313 
314 #ifdef CONFIG_TRAD_SIGNALS
315 SYSCALL_DEFINE3(sigaction, int, sig, const struct sigaction __user *, act,
316         struct sigaction __user *, oact)
317 {
318         struct k_sigaction new_ka, old_ka;
319         int ret;
320         int err = 0;
321 
322         if (act) {
323                 old_sigset_t mask;
324 
325                 if (!access_ok(VERIFY_READ, act, sizeof(*act)))
326                         return -EFAULT;
327                 err |= __get_user(new_ka.sa.sa_handler, &act->sa_handler);
328                 err |= __get_user(new_ka.sa.sa_flags, &act->sa_flags);
329                 err |= __get_user(mask, &act->sa_mask.sig[0]);
330                 if (err)
331                         return -EFAULT;
332 
333                 siginitset(&new_ka.sa.sa_mask, mask);
334         }
335 
336         ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
337 
338         if (!ret && oact) {
339                 if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)))
340                         return -EFAULT;
341                 err |= __put_user(old_ka.sa.sa_flags, &oact->sa_flags);
342                 err |= __put_user(old_ka.sa.sa_handler, &oact->sa_handler);
343                 err |= __put_user(old_ka.sa.sa_mask.sig[0], oact->sa_mask.sig);
344                 err |= __put_user(0, &oact->sa_mask.sig[1]);
345                 err |= __put_user(0, &oact->sa_mask.sig[2]);
346                 err |= __put_user(0, &oact->sa_mask.sig[3]);
347                 if (err)
348                         return -EFAULT;
349         }
350 
351         return ret;
352 }
353 #endif
354 
355 #ifdef CONFIG_TRAD_SIGNALS
356 asmlinkage void sys_sigreturn(nabi_no_regargs struct pt_regs regs)
357 {
358         struct sigframe __user *frame;
359         sigset_t blocked;
360         int sig;
361 
362         frame = (struct sigframe __user *) regs.regs[29];
363         if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
364                 goto badframe;
365         if (__copy_from_user(&blocked, &frame->sf_mask, sizeof(blocked)))
366                 goto badframe;
367 
368         set_current_blocked(&blocked);
369 
370         sig = restore_sigcontext(&regs, &frame->sf_sc);
371         if (sig < 0)
372                 goto badframe;
373         else if (sig)
374                 force_sig(sig, current);
375 
376         /*
377          * Don't let your children do this ...
378          */
379         __asm__ __volatile__(
380                 "move\t$29, %0\n\t"
381                 "j\tsyscall_exit"
382                 :/* no outputs */
383                 :"r" (&regs));
384         /* Unreached */
385 
386 badframe:
387         force_sig(SIGSEGV, current);
388 }
389 #endif /* CONFIG_TRAD_SIGNALS */
390 
391 asmlinkage void sys_rt_sigreturn(nabi_no_regargs struct pt_regs regs)
392 {
393         struct rt_sigframe __user *frame;
394         sigset_t set;
395         int sig;
396 
397         frame = (struct rt_sigframe __user *) regs.regs[29];
398         if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
399                 goto badframe;
400         if (__copy_from_user(&set, &frame->rs_uc.uc_sigmask, sizeof(set)))
401                 goto badframe;
402 
403         set_current_blocked(&set);
404 
405         sig = restore_sigcontext(&regs, &frame->rs_uc.uc_mcontext);
406         if (sig < 0)
407                 goto badframe;
408         else if (sig)
409                 force_sig(sig, current);
410 
411         if (restore_altstack(&frame->rs_uc.uc_stack))
412                 goto badframe;
413 
414         /*
415          * Don't let your children do this ...
416          */
417         __asm__ __volatile__(
418                 "move\t$29, %0\n\t"
419                 "j\tsyscall_exit"
420                 :/* no outputs */
421                 :"r" (&regs));
422         /* Unreached */
423 
424 badframe:
425         force_sig(SIGSEGV, current);
426 }
427 
428 #ifdef CONFIG_TRAD_SIGNALS
429 static int setup_frame(void *sig_return, struct ksignal *ksig,
430                        struct pt_regs *regs, sigset_t *set)
431 {
432         struct sigframe __user *frame;
433         int err = 0;
434 
435         frame = get_sigframe(ksig, regs, sizeof(*frame));
436         if (!access_ok(VERIFY_WRITE, frame, sizeof (*frame)))
437                 return -EFAULT;
438 
439         err |= setup_sigcontext(regs, &frame->sf_sc);
440         err |= __copy_to_user(&frame->sf_mask, set, sizeof(*set));
441         if (err)
442                 return -EFAULT;
443 
444         /*
445          * Arguments to signal handler:
446          *
447          *   a0 = signal number
448          *   a1 = 0 (should be cause)
449          *   a2 = pointer to struct sigcontext
450          *
451          * $25 and c0_epc point to the signal handler, $29 points to the
452          * struct sigframe.
453          */
454         regs->regs[ 4] = ksig->sig;
455         regs->regs[ 5] = 0;
456         regs->regs[ 6] = (unsigned long) &frame->sf_sc;
457         regs->regs[29] = (unsigned long) frame;
458         regs->regs[31] = (unsigned long) sig_return;
459         regs->cp0_epc = regs->regs[25] = (unsigned long) ksig->ka.sa.sa_handler;
460 
461         DEBUGP("SIG deliver (%s:%d): sp=0x%p pc=0x%lx ra=0x%lx\n",
462                current->comm, current->pid,
463                frame, regs->cp0_epc, regs->regs[31]);
464         return 0;
465 }
466 #endif
467 
468 static int setup_rt_frame(void *sig_return, struct ksignal *ksig,
469                           struct pt_regs *regs, sigset_t *set)
470 {
471         struct rt_sigframe __user *frame;
472         int err = 0;
473 
474         frame = get_sigframe(ksig, regs, sizeof(*frame));
475         if (!access_ok(VERIFY_WRITE, frame, sizeof (*frame)))
476                 return -EFAULT;
477 
478         /* Create siginfo.  */
479         err |= copy_siginfo_to_user(&frame->rs_info, &ksig->info);
480 
481         /* Create the ucontext.  */
482         err |= __put_user(0, &frame->rs_uc.uc_flags);
483         err |= __put_user(NULL, &frame->rs_uc.uc_link);
484         err |= __save_altstack(&frame->rs_uc.uc_stack, regs->regs[29]);
485         err |= setup_sigcontext(regs, &frame->rs_uc.uc_mcontext);
486         err |= __copy_to_user(&frame->rs_uc.uc_sigmask, set, sizeof(*set));
487 
488         if (err)
489                 return -EFAULT;
490 
491         /*
492          * Arguments to signal handler:
493          *
494          *   a0 = signal number
495          *   a1 = 0 (should be cause)
496          *   a2 = pointer to ucontext
497          *
498          * $25 and c0_epc point to the signal handler, $29 points to
499          * the struct rt_sigframe.
500          */
501         regs->regs[ 4] = ksig->sig;
502         regs->regs[ 5] = (unsigned long) &frame->rs_info;
503         regs->regs[ 6] = (unsigned long) &frame->rs_uc;
504         regs->regs[29] = (unsigned long) frame;
505         regs->regs[31] = (unsigned long) sig_return;
506         regs->cp0_epc = regs->regs[25] = (unsigned long) ksig->ka.sa.sa_handler;
507 
508         DEBUGP("SIG deliver (%s:%d): sp=0x%p pc=0x%lx ra=0x%lx\n",
509                current->comm, current->pid,
510                frame, regs->cp0_epc, regs->regs[31]);
511 
512         return 0;
513 }
514 
515 struct mips_abi mips_abi = {
516 #ifdef CONFIG_TRAD_SIGNALS
517         .setup_frame    = setup_frame,
518         .signal_return_offset = offsetof(struct mips_vdso, signal_trampoline),
519 #endif
520         .setup_rt_frame = setup_rt_frame,
521         .rt_signal_return_offset =
522                 offsetof(struct mips_vdso, rt_signal_trampoline),
523         .restart        = __NR_restart_syscall
524 };
525 
526 static void handle_signal(struct ksignal *ksig, struct pt_regs *regs)
527 {
528         sigset_t *oldset = sigmask_to_save();
529         int ret;
530         struct mips_abi *abi = current->thread.abi;
531 #ifdef CONFIG_CPU_MICROMIPS
532         void *vdso;
533         unsigned long tmp = (unsigned long)current->mm->context.vdso;
534 
535         set_isa16_mode(tmp);
536         vdso = (void *)tmp;
537 #else
538         void *vdso = current->mm->context.vdso;
539 #endif
540 
541         if (regs->regs[0]) {
542                 switch(regs->regs[2]) {
543                 case ERESTART_RESTARTBLOCK:
544                 case ERESTARTNOHAND:
545                         regs->regs[2] = EINTR;
546                         break;
547                 case ERESTARTSYS:
548                         if (!(ksig->ka.sa.sa_flags & SA_RESTART)) {
549                                 regs->regs[2] = EINTR;
550                                 break;
551                         }
552                 /* fallthrough */
553                 case ERESTARTNOINTR:
554                         regs->regs[7] = regs->regs[26];
555                         regs->regs[2] = regs->regs[0];
556                         regs->cp0_epc -= 4;
557                 }
558 
559                 regs->regs[0] = 0;              /* Don't deal with this again.  */
560         }
561 
562         if (sig_uses_siginfo(&ksig->ka))
563                 ret = abi->setup_rt_frame(vdso + abi->rt_signal_return_offset,
564                                           ksig, regs, oldset);
565         else
566                 ret = abi->setup_frame(vdso + abi->signal_return_offset, ksig,
567                                        regs, oldset);
568 
569         signal_setup_done(ret, ksig, 0);
570 }
571 
572 static void do_signal(struct pt_regs *regs)
573 {
574         struct ksignal ksig;
575 
576         if (get_signal(&ksig)) {
577                 /* Whee!  Actually deliver the signal.  */
578                 handle_signal(&ksig, regs);
579                 return;
580         }
581 
582         if (regs->regs[0]) {
583                 switch (regs->regs[2]) {
584                 case ERESTARTNOHAND:
585                 case ERESTARTSYS:
586                 case ERESTARTNOINTR:
587                         regs->regs[2] = regs->regs[0];
588                         regs->regs[7] = regs->regs[26];
589                         regs->cp0_epc -= 4;
590                         break;
591 
592                 case ERESTART_RESTARTBLOCK:
593                         regs->regs[2] = current->thread.abi->restart;
594                         regs->regs[7] = regs->regs[26];
595                         regs->cp0_epc -= 4;
596                         break;
597                 }
598                 regs->regs[0] = 0;      /* Don't deal with this again.  */
599         }
600 
601         /*
602          * If there's no signal to deliver, we just put the saved sigmask
603          * back
604          */
605         restore_saved_sigmask();
606 }
607 
608 /*
609  * notification of userspace execution resumption
610  * - triggered by the TIF_WORK_MASK flags
611  */
612 asmlinkage void do_notify_resume(struct pt_regs *regs, void *unused,
613         __u32 thread_info_flags)
614 {
615         local_irq_enable();
616 
617         user_exit();
618 
619         /* deal with pending signal delivery */
620         if (thread_info_flags & _TIF_SIGPENDING)
621                 do_signal(regs);
622 
623         if (thread_info_flags & _TIF_NOTIFY_RESUME) {
624                 clear_thread_flag(TIF_NOTIFY_RESUME);
625                 tracehook_notify_resume(regs);
626         }
627 
628         user_enter();
629 }
630 
631 #ifdef CONFIG_SMP
632 #ifndef CONFIG_EVA
633 static int smp_save_fp_context(struct sigcontext __user *sc)
634 {
635         return raw_cpu_has_fpu
636                ? _save_fp_context(sc)
637                : copy_fp_to_sigcontext(sc);
638 }
639 
640 static int smp_restore_fp_context(struct sigcontext __user *sc)
641 {
642         return raw_cpu_has_fpu
643                ? _restore_fp_context(sc)
644                : copy_fp_from_sigcontext(sc);
645 }
646 #endif /* CONFIG_EVA */
647 #endif
648 
649 static int signal_setup(void)
650 {
651 #ifndef CONFIG_EVA
652 #ifdef CONFIG_SMP
653         /* For now just do the cpu_has_fpu check when the functions are invoked */
654         save_fp_context = smp_save_fp_context;
655         restore_fp_context = smp_restore_fp_context;
656 #else
657         if (cpu_has_fpu) {
658                 save_fp_context = _save_fp_context;
659                 restore_fp_context = _restore_fp_context;
660         } else {
661                 save_fp_context = copy_fp_to_sigcontext;
662                 restore_fp_context = copy_fp_from_sigcontext;
663         }
664 #endif /* CONFIG_SMP */
665 #else
666         save_fp_context = copy_fp_to_sigcontext;
667         restore_fp_context = copy_fp_from_sigcontext;
668 #endif
669 
670         return 0;
671 }
672 
673 arch_initcall(signal_setup);
674 

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