1 /* 2 * linux/arch/arm/kernel/signal.c 3 * 4 * Copyright (C) 1995-2009 Russell King 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License version 2 as 8 * published by the Free Software Foundation. 9 */ 10 #include <linux/errno.h> 11 #include <linux/random.h> 12 #include <linux/signal.h> 13 #include <linux/personality.h> 14 #include <linux/uaccess.h> 15 #include <linux/tracehook.h> 16 17 #include <asm/elf.h> 18 #include <asm/cacheflush.h> 19 #include <asm/traps.h> 20 #include <asm/ucontext.h> 21 #include <asm/unistd.h> 22 #include <asm/vfp.h> 23 24 /* 25 * For ARM syscalls, we encode the syscall number into the instruction. 26 */ 27 #define SWI_SYS_SIGRETURN (0xef000000|(__NR_sigreturn)|(__NR_OABI_SYSCALL_BASE)) 28 #define SWI_SYS_RT_SIGRETURN (0xef000000|(__NR_rt_sigreturn)|(__NR_OABI_SYSCALL_BASE)) 29 30 /* 31 * With EABI, the syscall number has to be loaded into r7. 32 */ 33 #define MOV_R7_NR_SIGRETURN (0xe3a07000 | (__NR_sigreturn - __NR_SYSCALL_BASE)) 34 #define MOV_R7_NR_RT_SIGRETURN (0xe3a07000 | (__NR_rt_sigreturn - __NR_SYSCALL_BASE)) 35 36 /* 37 * For Thumb syscalls, we pass the syscall number via r7. We therefore 38 * need two 16-bit instructions. 39 */ 40 #define SWI_THUMB_SIGRETURN (0xdf00 << 16 | 0x2700 | (__NR_sigreturn - __NR_SYSCALL_BASE)) 41 #define SWI_THUMB_RT_SIGRETURN (0xdf00 << 16 | 0x2700 | (__NR_rt_sigreturn - __NR_SYSCALL_BASE)) 42 43 static const unsigned long sigreturn_codes[7] = { 44 MOV_R7_NR_SIGRETURN, SWI_SYS_SIGRETURN, SWI_THUMB_SIGRETURN, 45 MOV_R7_NR_RT_SIGRETURN, SWI_SYS_RT_SIGRETURN, SWI_THUMB_RT_SIGRETURN, 46 }; 47 48 static unsigned long signal_return_offset; 49 50 #ifdef CONFIG_CRUNCH 51 static int preserve_crunch_context(struct crunch_sigframe __user *frame) 52 { 53 char kbuf[sizeof(*frame) + 8]; 54 struct crunch_sigframe *kframe; 55 56 /* the crunch context must be 64 bit aligned */ 57 kframe = (struct crunch_sigframe *)((unsigned long)(kbuf + 8) & ~7); 58 kframe->magic = CRUNCH_MAGIC; 59 kframe->size = CRUNCH_STORAGE_SIZE; 60 crunch_task_copy(current_thread_info(), &kframe->storage); 61 return __copy_to_user(frame, kframe, sizeof(*frame)); 62 } 63 64 static int restore_crunch_context(struct crunch_sigframe __user *frame) 65 { 66 char kbuf[sizeof(*frame) + 8]; 67 struct crunch_sigframe *kframe; 68 69 /* the crunch context must be 64 bit aligned */ 70 kframe = (struct crunch_sigframe *)((unsigned long)(kbuf + 8) & ~7); 71 if (__copy_from_user(kframe, frame, sizeof(*frame))) 72 return -1; 73 if (kframe->magic != CRUNCH_MAGIC || 74 kframe->size != CRUNCH_STORAGE_SIZE) 75 return -1; 76 crunch_task_restore(current_thread_info(), &kframe->storage); 77 return 0; 78 } 79 #endif 80 81 #ifdef CONFIG_IWMMXT 82 83 static int preserve_iwmmxt_context(struct iwmmxt_sigframe *frame) 84 { 85 char kbuf[sizeof(*frame) + 8]; 86 struct iwmmxt_sigframe *kframe; 87 88 /* the iWMMXt context must be 64 bit aligned */ 89 kframe = (struct iwmmxt_sigframe *)((unsigned long)(kbuf + 8) & ~7); 90 kframe->magic = IWMMXT_MAGIC; 91 kframe->size = IWMMXT_STORAGE_SIZE; 92 iwmmxt_task_copy(current_thread_info(), &kframe->storage); 93 return __copy_to_user(frame, kframe, sizeof(*frame)); 94 } 95 96 static int restore_iwmmxt_context(struct iwmmxt_sigframe *frame) 97 { 98 char kbuf[sizeof(*frame) + 8]; 99 struct iwmmxt_sigframe *kframe; 100 101 /* the iWMMXt context must be 64 bit aligned */ 102 kframe = (struct iwmmxt_sigframe *)((unsigned long)(kbuf + 8) & ~7); 103 if (__copy_from_user(kframe, frame, sizeof(*frame))) 104 return -1; 105 if (kframe->magic != IWMMXT_MAGIC || 106 kframe->size != IWMMXT_STORAGE_SIZE) 107 return -1; 108 iwmmxt_task_restore(current_thread_info(), &kframe->storage); 109 return 0; 110 } 111 112 #endif 113 114 #ifdef CONFIG_VFP 115 116 static int preserve_vfp_context(struct vfp_sigframe __user *frame) 117 { 118 const unsigned long magic = VFP_MAGIC; 119 const unsigned long size = VFP_STORAGE_SIZE; 120 int err = 0; 121 122 __put_user_error(magic, &frame->magic, err); 123 __put_user_error(size, &frame->size, err); 124 125 if (err) 126 return -EFAULT; 127 128 return vfp_preserve_user_clear_hwstate(&frame->ufp, &frame->ufp_exc); 129 } 130 131 static int restore_vfp_context(struct vfp_sigframe __user *frame) 132 { 133 unsigned long magic; 134 unsigned long size; 135 int err = 0; 136 137 __get_user_error(magic, &frame->magic, err); 138 __get_user_error(size, &frame->size, err); 139 140 if (err) 141 return -EFAULT; 142 if (magic != VFP_MAGIC || size != VFP_STORAGE_SIZE) 143 return -EINVAL; 144 145 return vfp_restore_user_hwstate(&frame->ufp, &frame->ufp_exc); 146 } 147 148 #endif 149 150 /* 151 * Do a signal return; undo the signal stack. These are aligned to 64-bit. 152 */ 153 struct sigframe { 154 struct ucontext uc; 155 unsigned long retcode[2]; 156 }; 157 158 struct rt_sigframe { 159 struct siginfo info; 160 struct sigframe sig; 161 }; 162 163 static int restore_sigframe(struct pt_regs *regs, struct sigframe __user *sf) 164 { 165 struct aux_sigframe __user *aux; 166 sigset_t set; 167 int err; 168 169 err = __copy_from_user(&set, &sf->uc.uc_sigmask, sizeof(set)); 170 if (err == 0) 171 set_current_blocked(&set); 172 173 __get_user_error(regs->ARM_r0, &sf->uc.uc_mcontext.arm_r0, err); 174 __get_user_error(regs->ARM_r1, &sf->uc.uc_mcontext.arm_r1, err); 175 __get_user_error(regs->ARM_r2, &sf->uc.uc_mcontext.arm_r2, err); 176 __get_user_error(regs->ARM_r3, &sf->uc.uc_mcontext.arm_r3, err); 177 __get_user_error(regs->ARM_r4, &sf->uc.uc_mcontext.arm_r4, err); 178 __get_user_error(regs->ARM_r5, &sf->uc.uc_mcontext.arm_r5, err); 179 __get_user_error(regs->ARM_r6, &sf->uc.uc_mcontext.arm_r6, err); 180 __get_user_error(regs->ARM_r7, &sf->uc.uc_mcontext.arm_r7, err); 181 __get_user_error(regs->ARM_r8, &sf->uc.uc_mcontext.arm_r8, err); 182 __get_user_error(regs->ARM_r9, &sf->uc.uc_mcontext.arm_r9, err); 183 __get_user_error(regs->ARM_r10, &sf->uc.uc_mcontext.arm_r10, err); 184 __get_user_error(regs->ARM_fp, &sf->uc.uc_mcontext.arm_fp, err); 185 __get_user_error(regs->ARM_ip, &sf->uc.uc_mcontext.arm_ip, err); 186 __get_user_error(regs->ARM_sp, &sf->uc.uc_mcontext.arm_sp, err); 187 __get_user_error(regs->ARM_lr, &sf->uc.uc_mcontext.arm_lr, err); 188 __get_user_error(regs->ARM_pc, &sf->uc.uc_mcontext.arm_pc, err); 189 __get_user_error(regs->ARM_cpsr, &sf->uc.uc_mcontext.arm_cpsr, err); 190 191 err |= !valid_user_regs(regs); 192 193 aux = (struct aux_sigframe __user *) sf->uc.uc_regspace; 194 #ifdef CONFIG_CRUNCH 195 if (err == 0) 196 err |= restore_crunch_context(&aux->crunch); 197 #endif 198 #ifdef CONFIG_IWMMXT 199 if (err == 0 && test_thread_flag(TIF_USING_IWMMXT)) 200 err |= restore_iwmmxt_context(&aux->iwmmxt); 201 #endif 202 #ifdef CONFIG_VFP 203 if (err == 0) 204 err |= restore_vfp_context(&aux->vfp); 205 #endif 206 207 return err; 208 } 209 210 asmlinkage int sys_sigreturn(struct pt_regs *regs) 211 { 212 struct sigframe __user *frame; 213 214 /* Always make any pending restarted system calls return -EINTR */ 215 current_thread_info()->restart_block.fn = do_no_restart_syscall; 216 217 /* 218 * Since we stacked the signal on a 64-bit boundary, 219 * then 'sp' should be word aligned here. If it's 220 * not, then the user is trying to mess with us. 221 */ 222 if (regs->ARM_sp & 7) 223 goto badframe; 224 225 frame = (struct sigframe __user *)regs->ARM_sp; 226 227 if (!access_ok(VERIFY_READ, frame, sizeof (*frame))) 228 goto badframe; 229 230 if (restore_sigframe(regs, frame)) 231 goto badframe; 232 233 return regs->ARM_r0; 234 235 badframe: 236 force_sig(SIGSEGV, current); 237 return 0; 238 } 239 240 asmlinkage int sys_rt_sigreturn(struct pt_regs *regs) 241 { 242 struct rt_sigframe __user *frame; 243 244 /* Always make any pending restarted system calls return -EINTR */ 245 current_thread_info()->restart_block.fn = do_no_restart_syscall; 246 247 /* 248 * Since we stacked the signal on a 64-bit boundary, 249 * then 'sp' should be word aligned here. If it's 250 * not, then the user is trying to mess with us. 251 */ 252 if (regs->ARM_sp & 7) 253 goto badframe; 254 255 frame = (struct rt_sigframe __user *)regs->ARM_sp; 256 257 if (!access_ok(VERIFY_READ, frame, sizeof (*frame))) 258 goto badframe; 259 260 if (restore_sigframe(regs, &frame->sig)) 261 goto badframe; 262 263 if (restore_altstack(&frame->sig.uc.uc_stack)) 264 goto badframe; 265 266 return regs->ARM_r0; 267 268 badframe: 269 force_sig(SIGSEGV, current); 270 return 0; 271 } 272 273 static int 274 setup_sigframe(struct sigframe __user *sf, struct pt_regs *regs, sigset_t *set) 275 { 276 struct aux_sigframe __user *aux; 277 int err = 0; 278 279 __put_user_error(regs->ARM_r0, &sf->uc.uc_mcontext.arm_r0, err); 280 __put_user_error(regs->ARM_r1, &sf->uc.uc_mcontext.arm_r1, err); 281 __put_user_error(regs->ARM_r2, &sf->uc.uc_mcontext.arm_r2, err); 282 __put_user_error(regs->ARM_r3, &sf->uc.uc_mcontext.arm_r3, err); 283 __put_user_error(regs->ARM_r4, &sf->uc.uc_mcontext.arm_r4, err); 284 __put_user_error(regs->ARM_r5, &sf->uc.uc_mcontext.arm_r5, err); 285 __put_user_error(regs->ARM_r6, &sf->uc.uc_mcontext.arm_r6, err); 286 __put_user_error(regs->ARM_r7, &sf->uc.uc_mcontext.arm_r7, err); 287 __put_user_error(regs->ARM_r8, &sf->uc.uc_mcontext.arm_r8, err); 288 __put_user_error(regs->ARM_r9, &sf->uc.uc_mcontext.arm_r9, err); 289 __put_user_error(regs->ARM_r10, &sf->uc.uc_mcontext.arm_r10, err); 290 __put_user_error(regs->ARM_fp, &sf->uc.uc_mcontext.arm_fp, err); 291 __put_user_error(regs->ARM_ip, &sf->uc.uc_mcontext.arm_ip, err); 292 __put_user_error(regs->ARM_sp, &sf->uc.uc_mcontext.arm_sp, err); 293 __put_user_error(regs->ARM_lr, &sf->uc.uc_mcontext.arm_lr, err); 294 __put_user_error(regs->ARM_pc, &sf->uc.uc_mcontext.arm_pc, err); 295 __put_user_error(regs->ARM_cpsr, &sf->uc.uc_mcontext.arm_cpsr, err); 296 297 __put_user_error(current->thread.trap_no, &sf->uc.uc_mcontext.trap_no, err); 298 __put_user_error(current->thread.error_code, &sf->uc.uc_mcontext.error_code, err); 299 __put_user_error(current->thread.address, &sf->uc.uc_mcontext.fault_address, err); 300 __put_user_error(set->sig[0], &sf->uc.uc_mcontext.oldmask, err); 301 302 err |= __copy_to_user(&sf->uc.uc_sigmask, set, sizeof(*set)); 303 304 aux = (struct aux_sigframe __user *) sf->uc.uc_regspace; 305 #ifdef CONFIG_CRUNCH 306 if (err == 0) 307 err |= preserve_crunch_context(&aux->crunch); 308 #endif 309 #ifdef CONFIG_IWMMXT 310 if (err == 0 && test_thread_flag(TIF_USING_IWMMXT)) 311 err |= preserve_iwmmxt_context(&aux->iwmmxt); 312 #endif 313 #ifdef CONFIG_VFP 314 if (err == 0) 315 err |= preserve_vfp_context(&aux->vfp); 316 #endif 317 __put_user_error(0, &aux->end_magic, err); 318 319 return err; 320 } 321 322 static inline void __user * 323 get_sigframe(struct ksignal *ksig, struct pt_regs *regs, int framesize) 324 { 325 unsigned long sp = sigsp(regs->ARM_sp, ksig); 326 void __user *frame; 327 328 /* 329 * ATPCS B01 mandates 8-byte alignment 330 */ 331 frame = (void __user *)((sp - framesize) & ~7); 332 333 /* 334 * Check that we can actually write to the signal frame. 335 */ 336 if (!access_ok(VERIFY_WRITE, frame, framesize)) 337 frame = NULL; 338 339 return frame; 340 } 341 342 /* 343 * translate the signal 344 */ 345 static inline int map_sig(int sig) 346 { 347 struct thread_info *thread = current_thread_info(); 348 if (sig < 32 && thread->exec_domain && thread->exec_domain->signal_invmap) 349 sig = thread->exec_domain->signal_invmap[sig]; 350 return sig; 351 } 352 353 static int 354 setup_return(struct pt_regs *regs, struct ksignal *ksig, 355 unsigned long __user *rc, void __user *frame) 356 { 357 unsigned long handler = (unsigned long)ksig->ka.sa.sa_handler; 358 unsigned long retcode; 359 int thumb = 0; 360 unsigned long cpsr = regs->ARM_cpsr & ~(PSR_f | PSR_E_BIT); 361 362 cpsr |= PSR_ENDSTATE; 363 364 /* 365 * Maybe we need to deliver a 32-bit signal to a 26-bit task. 366 */ 367 if (ksig->ka.sa.sa_flags & SA_THIRTYTWO) 368 cpsr = (cpsr & ~MODE_MASK) | USR_MODE; 369 370 #ifdef CONFIG_ARM_THUMB 371 if (elf_hwcap & HWCAP_THUMB) { 372 /* 373 * The LSB of the handler determines if we're going to 374 * be using THUMB or ARM mode for this signal handler. 375 */ 376 thumb = handler & 1; 377 378 if (thumb) { 379 cpsr |= PSR_T_BIT; 380 #if __LINUX_ARM_ARCH__ >= 7 381 /* clear the If-Then Thumb-2 execution state */ 382 cpsr &= ~PSR_IT_MASK; 383 #endif 384 } else 385 cpsr &= ~PSR_T_BIT; 386 } 387 #endif 388 389 if (ksig->ka.sa.sa_flags & SA_RESTORER) { 390 retcode = (unsigned long)ksig->ka.sa.sa_restorer; 391 } else { 392 unsigned int idx = thumb << 1; 393 394 if (ksig->ka.sa.sa_flags & SA_SIGINFO) 395 idx += 3; 396 397 /* 398 * Put the sigreturn code on the stack no matter which return 399 * mechanism we use in order to remain ABI compliant 400 */ 401 if (__put_user(sigreturn_codes[idx], rc) || 402 __put_user(sigreturn_codes[idx+1], rc+1)) 403 return 1; 404 405 #ifdef CONFIG_MMU 406 if (cpsr & MODE32_BIT) { 407 struct mm_struct *mm = current->mm; 408 409 /* 410 * 32-bit code can use the signal return page 411 * except when the MPU has protected the vectors 412 * page from PL0 413 */ 414 retcode = mm->context.sigpage + signal_return_offset + 415 (idx << 2) + thumb; 416 } else 417 #endif 418 { 419 /* 420 * Ensure that the instruction cache sees 421 * the return code written onto the stack. 422 */ 423 flush_icache_range((unsigned long)rc, 424 (unsigned long)(rc + 2)); 425 426 retcode = ((unsigned long)rc) + thumb; 427 } 428 } 429 430 regs->ARM_r0 = map_sig(ksig->sig); 431 regs->ARM_sp = (unsigned long)frame; 432 regs->ARM_lr = retcode; 433 regs->ARM_pc = handler; 434 regs->ARM_cpsr = cpsr; 435 436 return 0; 437 } 438 439 static int 440 setup_frame(struct ksignal *ksig, sigset_t *set, struct pt_regs *regs) 441 { 442 struct sigframe __user *frame = get_sigframe(ksig, regs, sizeof(*frame)); 443 int err = 0; 444 445 if (!frame) 446 return 1; 447 448 /* 449 * Set uc.uc_flags to a value which sc.trap_no would never have. 450 */ 451 __put_user_error(0x5ac3c35a, &frame->uc.uc_flags, err); 452 453 err |= setup_sigframe(frame, regs, set); 454 if (err == 0) 455 err = setup_return(regs, ksig, frame->retcode, frame); 456 457 return err; 458 } 459 460 static int 461 setup_rt_frame(struct ksignal *ksig, sigset_t *set, struct pt_regs *regs) 462 { 463 struct rt_sigframe __user *frame = get_sigframe(ksig, regs, sizeof(*frame)); 464 int err = 0; 465 466 if (!frame) 467 return 1; 468 469 err |= copy_siginfo_to_user(&frame->info, &ksig->info); 470 471 __put_user_error(0, &frame->sig.uc.uc_flags, err); 472 __put_user_error(NULL, &frame->sig.uc.uc_link, err); 473 474 err |= __save_altstack(&frame->sig.uc.uc_stack, regs->ARM_sp); 475 err |= setup_sigframe(&frame->sig, regs, set); 476 if (err == 0) 477 err = setup_return(regs, ksig, frame->sig.retcode, frame); 478 479 if (err == 0) { 480 /* 481 * For realtime signals we must also set the second and third 482 * arguments for the signal handler. 483 * -- Peter Maydell <pmaydell@chiark.greenend.org.uk> 2000-12-06 484 */ 485 regs->ARM_r1 = (unsigned long)&frame->info; 486 regs->ARM_r2 = (unsigned long)&frame->sig.uc; 487 } 488 489 return err; 490 } 491 492 /* 493 * OK, we're invoking a handler 494 */ 495 static void handle_signal(struct ksignal *ksig, struct pt_regs *regs) 496 { 497 sigset_t *oldset = sigmask_to_save(); 498 int ret; 499 500 /* 501 * Set up the stack frame 502 */ 503 if (ksig->ka.sa.sa_flags & SA_SIGINFO) 504 ret = setup_rt_frame(ksig, oldset, regs); 505 else 506 ret = setup_frame(ksig, oldset, regs); 507 508 /* 509 * Check that the resulting registers are actually sane. 510 */ 511 ret |= !valid_user_regs(regs); 512 513 signal_setup_done(ret, ksig, 0); 514 } 515 516 /* 517 * Note that 'init' is a special process: it doesn't get signals it doesn't 518 * want to handle. Thus you cannot kill init even with a SIGKILL even by 519 * mistake. 520 * 521 * Note that we go through the signals twice: once to check the signals that 522 * the kernel can handle, and then we build all the user-level signal handling 523 * stack-frames in one go after that. 524 */ 525 static int do_signal(struct pt_regs *regs, int syscall) 526 { 527 unsigned int retval = 0, continue_addr = 0, restart_addr = 0; 528 struct ksignal ksig; 529 int restart = 0; 530 531 /* 532 * If we were from a system call, check for system call restarting... 533 */ 534 if (syscall) { 535 continue_addr = regs->ARM_pc; 536 restart_addr = continue_addr - (thumb_mode(regs) ? 2 : 4); 537 retval = regs->ARM_r0; 538 539 /* 540 * Prepare for system call restart. We do this here so that a 541 * debugger will see the already changed PSW. 542 */ 543 switch (retval) { 544 case -ERESTART_RESTARTBLOCK: 545 restart -= 2; 546 case -ERESTARTNOHAND: 547 case -ERESTARTSYS: 548 case -ERESTARTNOINTR: 549 restart++; 550 regs->ARM_r0 = regs->ARM_ORIG_r0; 551 regs->ARM_pc = restart_addr; 552 break; 553 } 554 } 555 556 /* 557 * Get the signal to deliver. When running under ptrace, at this 558 * point the debugger may change all our registers ... 559 */ 560 /* 561 * Depending on the signal settings we may need to revert the 562 * decision to restart the system call. But skip this if a 563 * debugger has chosen to restart at a different PC. 564 */ 565 if (get_signal(&ksig)) { 566 /* handler */ 567 if (unlikely(restart) && regs->ARM_pc == restart_addr) { 568 if (retval == -ERESTARTNOHAND || 569 retval == -ERESTART_RESTARTBLOCK 570 || (retval == -ERESTARTSYS 571 && !(ksig.ka.sa.sa_flags & SA_RESTART))) { 572 regs->ARM_r0 = -EINTR; 573 regs->ARM_pc = continue_addr; 574 } 575 } 576 handle_signal(&ksig, regs); 577 } else { 578 /* no handler */ 579 restore_saved_sigmask(); 580 if (unlikely(restart) && regs->ARM_pc == restart_addr) { 581 regs->ARM_pc = continue_addr; 582 return restart; 583 } 584 } 585 return 0; 586 } 587 588 asmlinkage int 589 do_work_pending(struct pt_regs *regs, unsigned int thread_flags, int syscall) 590 { 591 do { 592 if (likely(thread_flags & _TIF_NEED_RESCHED)) { 593 schedule(); 594 } else { 595 if (unlikely(!user_mode(regs))) 596 return 0; 597 local_irq_enable(); 598 if (thread_flags & _TIF_SIGPENDING) { 599 int restart = do_signal(regs, syscall); 600 if (unlikely(restart)) { 601 /* 602 * Restart without handlers. 603 * Deal with it without leaving 604 * the kernel space. 605 */ 606 return restart; 607 } 608 syscall = 0; 609 } else { 610 clear_thread_flag(TIF_NOTIFY_RESUME); 611 tracehook_notify_resume(regs); 612 } 613 } 614 local_irq_disable(); 615 thread_flags = current_thread_info()->flags; 616 } while (thread_flags & _TIF_WORK_MASK); 617 return 0; 618 } 619 620 struct page *get_signal_page(void) 621 { 622 unsigned long ptr; 623 unsigned offset; 624 struct page *page; 625 void *addr; 626 627 page = alloc_pages(GFP_KERNEL, 0); 628 629 if (!page) 630 return NULL; 631 632 addr = page_address(page); 633 634 /* Give the signal return code some randomness */ 635 offset = 0x200 + (get_random_int() & 0x7fc); 636 signal_return_offset = offset; 637 638 /* 639 * Copy signal return handlers into the vector page, and 640 * set sigreturn to be a pointer to these. 641 */ 642 memcpy(addr + offset, sigreturn_codes, sizeof(sigreturn_codes)); 643 644 ptr = (unsigned long)addr + offset; 645 flush_icache_range(ptr, ptr + sizeof(sigreturn_codes)); 646 647 return page; 648 } 649