1 /* 2 * linux/arch/arm/kernel/signal.c 3 * 4 * Copyright (C) 1995-2002 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/config.h> 11 #include <linux/errno.h> 12 #include <linux/signal.h> 13 #include <linux/ptrace.h> 14 #include <linux/personality.h> 15 16 #include <asm/cacheflush.h> 17 #include <asm/ucontext.h> 18 #include <asm/uaccess.h> 19 #include <asm/unistd.h> 20 21 #include "ptrace.h" 22 #include "signal.h" 23 24 #define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP))) 25 26 /* 27 * For ARM syscalls, we encode the syscall number into the instruction. 28 */ 29 #define SWI_SYS_SIGRETURN (0xef000000|(__NR_sigreturn)) 30 #define SWI_SYS_RT_SIGRETURN (0xef000000|(__NR_rt_sigreturn)) 31 32 /* 33 * With EABI, the syscall number has to be loaded into r7. 34 */ 35 #define MOV_R7_NR_SIGRETURN (0xe3a07000 | (__NR_sigreturn - __NR_SYSCALL_BASE)) 36 #define MOV_R7_NR_RT_SIGRETURN (0xe3a07000 | (__NR_rt_sigreturn - __NR_SYSCALL_BASE)) 37 38 /* 39 * For Thumb syscalls, we pass the syscall number via r7. We therefore 40 * need two 16-bit instructions. 41 */ 42 #define SWI_THUMB_SIGRETURN (0xdf00 << 16 | 0x2700 | (__NR_sigreturn - __NR_SYSCALL_BASE)) 43 #define SWI_THUMB_RT_SIGRETURN (0xdf00 << 16 | 0x2700 | (__NR_rt_sigreturn - __NR_SYSCALL_BASE)) 44 45 const unsigned long sigreturn_codes[7] = { 46 MOV_R7_NR_SIGRETURN, SWI_SYS_SIGRETURN, SWI_THUMB_SIGRETURN, 47 MOV_R7_NR_RT_SIGRETURN, SWI_SYS_RT_SIGRETURN, SWI_THUMB_RT_SIGRETURN, 48 }; 49 50 static int do_signal(sigset_t *oldset, struct pt_regs * regs, int syscall); 51 52 /* 53 * atomically swap in the new signal mask, and wait for a signal. 54 */ 55 asmlinkage int sys_sigsuspend(int restart, unsigned long oldmask, old_sigset_t mask, struct pt_regs *regs) 56 { 57 sigset_t saveset; 58 59 mask &= _BLOCKABLE; 60 spin_lock_irq(¤t->sighand->siglock); 61 saveset = current->blocked; 62 siginitset(¤t->blocked, mask); 63 recalc_sigpending(); 64 spin_unlock_irq(¤t->sighand->siglock); 65 regs->ARM_r0 = -EINTR; 66 67 while (1) { 68 current->state = TASK_INTERRUPTIBLE; 69 schedule(); 70 if (do_signal(&saveset, regs, 0)) 71 return regs->ARM_r0; 72 } 73 } 74 75 asmlinkage int 76 sys_rt_sigsuspend(sigset_t __user *unewset, size_t sigsetsize, struct pt_regs *regs) 77 { 78 sigset_t saveset, newset; 79 80 /* XXX: Don't preclude handling different sized sigset_t's. */ 81 if (sigsetsize != sizeof(sigset_t)) 82 return -EINVAL; 83 84 if (copy_from_user(&newset, unewset, sizeof(newset))) 85 return -EFAULT; 86 sigdelsetmask(&newset, ~_BLOCKABLE); 87 88 spin_lock_irq(¤t->sighand->siglock); 89 saveset = current->blocked; 90 current->blocked = newset; 91 recalc_sigpending(); 92 spin_unlock_irq(¤t->sighand->siglock); 93 regs->ARM_r0 = -EINTR; 94 95 while (1) { 96 current->state = TASK_INTERRUPTIBLE; 97 schedule(); 98 if (do_signal(&saveset, regs, 0)) 99 return regs->ARM_r0; 100 } 101 } 102 103 asmlinkage int 104 sys_sigaction(int sig, const struct old_sigaction __user *act, 105 struct old_sigaction __user *oact) 106 { 107 struct k_sigaction new_ka, old_ka; 108 int ret; 109 110 if (act) { 111 old_sigset_t mask; 112 if (!access_ok(VERIFY_READ, act, sizeof(*act)) || 113 __get_user(new_ka.sa.sa_handler, &act->sa_handler) || 114 __get_user(new_ka.sa.sa_restorer, &act->sa_restorer)) 115 return -EFAULT; 116 __get_user(new_ka.sa.sa_flags, &act->sa_flags); 117 __get_user(mask, &act->sa_mask); 118 siginitset(&new_ka.sa.sa_mask, mask); 119 } 120 121 ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL); 122 123 if (!ret && oact) { 124 if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) || 125 __put_user(old_ka.sa.sa_handler, &oact->sa_handler) || 126 __put_user(old_ka.sa.sa_restorer, &oact->sa_restorer)) 127 return -EFAULT; 128 __put_user(old_ka.sa.sa_flags, &oact->sa_flags); 129 __put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask); 130 } 131 132 return ret; 133 } 134 135 #ifdef CONFIG_IWMMXT 136 137 /* iwmmxt_area is 0x98 bytes long, preceeded by 8 bytes of signature */ 138 #define IWMMXT_STORAGE_SIZE (0x98 + 8) 139 #define IWMMXT_MAGIC0 0x12ef842a 140 #define IWMMXT_MAGIC1 0x1c07ca71 141 142 struct iwmmxt_sigframe { 143 unsigned long magic0; 144 unsigned long magic1; 145 unsigned long storage[0x98/4]; 146 }; 147 148 static int preserve_iwmmxt_context(struct iwmmxt_sigframe *frame) 149 { 150 char kbuf[sizeof(*frame) + 8]; 151 struct iwmmxt_sigframe *kframe; 152 153 /* the iWMMXt context must be 64 bit aligned */ 154 kframe = (struct iwmmxt_sigframe *)((unsigned long)(kbuf + 8) & ~7); 155 kframe->magic0 = IWMMXT_MAGIC0; 156 kframe->magic1 = IWMMXT_MAGIC1; 157 iwmmxt_task_copy(current_thread_info(), &kframe->storage); 158 return __copy_to_user(frame, kframe, sizeof(*frame)); 159 } 160 161 static int restore_iwmmxt_context(struct iwmmxt_sigframe *frame) 162 { 163 char kbuf[sizeof(*frame) + 8]; 164 struct iwmmxt_sigframe *kframe; 165 166 /* the iWMMXt context must be 64 bit aligned */ 167 kframe = (struct iwmmxt_sigframe *)((unsigned long)(kbuf + 8) & ~7); 168 if (__copy_from_user(kframe, frame, sizeof(*frame))) 169 return -1; 170 if (kframe->magic0 != IWMMXT_MAGIC0 || 171 kframe->magic1 != IWMMXT_MAGIC1) 172 return -1; 173 iwmmxt_task_restore(current_thread_info(), &kframe->storage); 174 return 0; 175 } 176 177 #endif 178 179 /* 180 * Auxiliary signal frame. This saves stuff like FP state. 181 * The layout of this structure is not part of the user ABI. 182 */ 183 struct aux_sigframe { 184 #ifdef CONFIG_IWMMXT 185 struct iwmmxt_sigframe iwmmxt; 186 #endif 187 #ifdef CONFIG_VFP 188 union vfp_state vfp; 189 #endif 190 }; 191 192 /* 193 * Do a signal return; undo the signal stack. These are aligned to 64-bit. 194 */ 195 struct sigframe { 196 struct sigcontext sc; 197 unsigned long extramask[_NSIG_WORDS-1]; 198 unsigned long retcode[2]; 199 struct aux_sigframe aux __attribute__((aligned(8))); 200 }; 201 202 struct rt_sigframe { 203 struct siginfo __user *pinfo; 204 void __user *puc; 205 struct siginfo info; 206 struct ucontext uc; 207 unsigned long retcode[2]; 208 struct aux_sigframe aux __attribute__((aligned(8))); 209 }; 210 211 static int 212 restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc, 213 struct aux_sigframe __user *aux) 214 { 215 int err = 0; 216 217 __get_user_error(regs->ARM_r0, &sc->arm_r0, err); 218 __get_user_error(regs->ARM_r1, &sc->arm_r1, err); 219 __get_user_error(regs->ARM_r2, &sc->arm_r2, err); 220 __get_user_error(regs->ARM_r3, &sc->arm_r3, err); 221 __get_user_error(regs->ARM_r4, &sc->arm_r4, err); 222 __get_user_error(regs->ARM_r5, &sc->arm_r5, err); 223 __get_user_error(regs->ARM_r6, &sc->arm_r6, err); 224 __get_user_error(regs->ARM_r7, &sc->arm_r7, err); 225 __get_user_error(regs->ARM_r8, &sc->arm_r8, err); 226 __get_user_error(regs->ARM_r9, &sc->arm_r9, err); 227 __get_user_error(regs->ARM_r10, &sc->arm_r10, err); 228 __get_user_error(regs->ARM_fp, &sc->arm_fp, err); 229 __get_user_error(regs->ARM_ip, &sc->arm_ip, err); 230 __get_user_error(regs->ARM_sp, &sc->arm_sp, err); 231 __get_user_error(regs->ARM_lr, &sc->arm_lr, err); 232 __get_user_error(regs->ARM_pc, &sc->arm_pc, err); 233 __get_user_error(regs->ARM_cpsr, &sc->arm_cpsr, err); 234 235 err |= !valid_user_regs(regs); 236 237 #ifdef CONFIG_IWMMXT 238 if (err == 0 && test_thread_flag(TIF_USING_IWMMXT)) 239 err |= restore_iwmmxt_context(&aux->iwmmxt); 240 #endif 241 #ifdef CONFIG_VFP 242 // if (err == 0) 243 // err |= vfp_restore_state(&aux->vfp); 244 #endif 245 246 return err; 247 } 248 249 asmlinkage int sys_sigreturn(struct pt_regs *regs) 250 { 251 struct sigframe __user *frame; 252 sigset_t set; 253 254 /* Always make any pending restarted system calls return -EINTR */ 255 current_thread_info()->restart_block.fn = do_no_restart_syscall; 256 257 /* 258 * Since we stacked the signal on a 64-bit boundary, 259 * then 'sp' should be word aligned here. If it's 260 * not, then the user is trying to mess with us. 261 */ 262 if (regs->ARM_sp & 7) 263 goto badframe; 264 265 frame = (struct sigframe __user *)regs->ARM_sp; 266 267 if (!access_ok(VERIFY_READ, frame, sizeof (*frame))) 268 goto badframe; 269 if (__get_user(set.sig[0], &frame->sc.oldmask) 270 || (_NSIG_WORDS > 1 271 && __copy_from_user(&set.sig[1], &frame->extramask, 272 sizeof(frame->extramask)))) 273 goto badframe; 274 275 sigdelsetmask(&set, ~_BLOCKABLE); 276 spin_lock_irq(¤t->sighand->siglock); 277 current->blocked = set; 278 recalc_sigpending(); 279 spin_unlock_irq(¤t->sighand->siglock); 280 281 if (restore_sigcontext(regs, &frame->sc, &frame->aux)) 282 goto badframe; 283 284 /* Send SIGTRAP if we're single-stepping */ 285 if (current->ptrace & PT_SINGLESTEP) { 286 ptrace_cancel_bpt(current); 287 send_sig(SIGTRAP, current, 1); 288 } 289 290 return regs->ARM_r0; 291 292 badframe: 293 force_sig(SIGSEGV, current); 294 return 0; 295 } 296 297 asmlinkage int sys_rt_sigreturn(struct pt_regs *regs) 298 { 299 struct rt_sigframe __user *frame; 300 sigset_t set; 301 302 /* Always make any pending restarted system calls return -EINTR */ 303 current_thread_info()->restart_block.fn = do_no_restart_syscall; 304 305 /* 306 * Since we stacked the signal on a 64-bit boundary, 307 * then 'sp' should be word aligned here. If it's 308 * not, then the user is trying to mess with us. 309 */ 310 if (regs->ARM_sp & 7) 311 goto badframe; 312 313 frame = (struct rt_sigframe __user *)regs->ARM_sp; 314 315 if (!access_ok(VERIFY_READ, frame, sizeof (*frame))) 316 goto badframe; 317 if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set))) 318 goto badframe; 319 320 sigdelsetmask(&set, ~_BLOCKABLE); 321 spin_lock_irq(¤t->sighand->siglock); 322 current->blocked = set; 323 recalc_sigpending(); 324 spin_unlock_irq(¤t->sighand->siglock); 325 326 if (restore_sigcontext(regs, &frame->uc.uc_mcontext, &frame->aux)) 327 goto badframe; 328 329 if (do_sigaltstack(&frame->uc.uc_stack, NULL, regs->ARM_sp) == -EFAULT) 330 goto badframe; 331 332 /* Send SIGTRAP if we're single-stepping */ 333 if (current->ptrace & PT_SINGLESTEP) { 334 ptrace_cancel_bpt(current); 335 send_sig(SIGTRAP, current, 1); 336 } 337 338 return regs->ARM_r0; 339 340 badframe: 341 force_sig(SIGSEGV, current); 342 return 0; 343 } 344 345 static int 346 setup_sigcontext(struct sigcontext __user *sc, struct aux_sigframe __user *aux, 347 struct pt_regs *regs, unsigned long mask) 348 { 349 int err = 0; 350 351 __put_user_error(regs->ARM_r0, &sc->arm_r0, err); 352 __put_user_error(regs->ARM_r1, &sc->arm_r1, err); 353 __put_user_error(regs->ARM_r2, &sc->arm_r2, err); 354 __put_user_error(regs->ARM_r3, &sc->arm_r3, err); 355 __put_user_error(regs->ARM_r4, &sc->arm_r4, err); 356 __put_user_error(regs->ARM_r5, &sc->arm_r5, err); 357 __put_user_error(regs->ARM_r6, &sc->arm_r6, err); 358 __put_user_error(regs->ARM_r7, &sc->arm_r7, err); 359 __put_user_error(regs->ARM_r8, &sc->arm_r8, err); 360 __put_user_error(regs->ARM_r9, &sc->arm_r9, err); 361 __put_user_error(regs->ARM_r10, &sc->arm_r10, err); 362 __put_user_error(regs->ARM_fp, &sc->arm_fp, err); 363 __put_user_error(regs->ARM_ip, &sc->arm_ip, err); 364 __put_user_error(regs->ARM_sp, &sc->arm_sp, err); 365 __put_user_error(regs->ARM_lr, &sc->arm_lr, err); 366 __put_user_error(regs->ARM_pc, &sc->arm_pc, err); 367 __put_user_error(regs->ARM_cpsr, &sc->arm_cpsr, err); 368 369 __put_user_error(current->thread.trap_no, &sc->trap_no, err); 370 __put_user_error(current->thread.error_code, &sc->error_code, err); 371 __put_user_error(current->thread.address, &sc->fault_address, err); 372 __put_user_error(mask, &sc->oldmask, err); 373 374 #ifdef CONFIG_IWMMXT 375 if (err == 0 && test_thread_flag(TIF_USING_IWMMXT)) 376 err |= preserve_iwmmxt_context(&aux->iwmmxt); 377 #endif 378 #ifdef CONFIG_VFP 379 // if (err == 0) 380 // err |= vfp_save_state(&aux->vfp); 381 #endif 382 383 return err; 384 } 385 386 static inline void __user * 387 get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, int framesize) 388 { 389 unsigned long sp = regs->ARM_sp; 390 void __user *frame; 391 392 /* 393 * This is the X/Open sanctioned signal stack switching. 394 */ 395 if ((ka->sa.sa_flags & SA_ONSTACK) && !sas_ss_flags(sp)) 396 sp = current->sas_ss_sp + current->sas_ss_size; 397 398 /* 399 * ATPCS B01 mandates 8-byte alignment 400 */ 401 frame = (void __user *)((sp - framesize) & ~7); 402 403 /* 404 * Check that we can actually write to the signal frame. 405 */ 406 if (!access_ok(VERIFY_WRITE, frame, framesize)) 407 frame = NULL; 408 409 return frame; 410 } 411 412 static int 413 setup_return(struct pt_regs *regs, struct k_sigaction *ka, 414 unsigned long __user *rc, void __user *frame, int usig) 415 { 416 unsigned long handler = (unsigned long)ka->sa.sa_handler; 417 unsigned long retcode; 418 int thumb = 0; 419 unsigned long cpsr = regs->ARM_cpsr & ~PSR_f; 420 421 /* 422 * Maybe we need to deliver a 32-bit signal to a 26-bit task. 423 */ 424 if (ka->sa.sa_flags & SA_THIRTYTWO) 425 cpsr = (cpsr & ~MODE_MASK) | USR_MODE; 426 427 #ifdef CONFIG_ARM_THUMB 428 if (elf_hwcap & HWCAP_THUMB) { 429 /* 430 * The LSB of the handler determines if we're going to 431 * be using THUMB or ARM mode for this signal handler. 432 */ 433 thumb = handler & 1; 434 435 if (thumb) 436 cpsr |= PSR_T_BIT; 437 else 438 cpsr &= ~PSR_T_BIT; 439 } 440 #endif 441 442 if (ka->sa.sa_flags & SA_RESTORER) { 443 retcode = (unsigned long)ka->sa.sa_restorer; 444 } else { 445 unsigned int idx = thumb << 1; 446 447 if (ka->sa.sa_flags & SA_SIGINFO) 448 idx += 3; 449 450 if (__put_user(sigreturn_codes[idx], rc) || 451 __put_user(sigreturn_codes[idx+1], rc+1)) 452 return 1; 453 454 if (cpsr & MODE32_BIT) { 455 /* 456 * 32-bit code can use the new high-page 457 * signal return code support. 458 */ 459 retcode = KERN_SIGRETURN_CODE + (idx << 2) + thumb; 460 } else { 461 /* 462 * Ensure that the instruction cache sees 463 * the return code written onto the stack. 464 */ 465 flush_icache_range((unsigned long)rc, 466 (unsigned long)(rc + 2)); 467 468 retcode = ((unsigned long)rc) + thumb; 469 } 470 } 471 472 regs->ARM_r0 = usig; 473 regs->ARM_sp = (unsigned long)frame; 474 regs->ARM_lr = retcode; 475 regs->ARM_pc = handler; 476 regs->ARM_cpsr = cpsr; 477 478 return 0; 479 } 480 481 static int 482 setup_frame(int usig, struct k_sigaction *ka, sigset_t *set, struct pt_regs *regs) 483 { 484 struct sigframe __user *frame = get_sigframe(ka, regs, sizeof(*frame)); 485 int err = 0; 486 487 if (!frame) 488 return 1; 489 490 err |= setup_sigcontext(&frame->sc, &frame->aux, regs, set->sig[0]); 491 492 if (_NSIG_WORDS > 1) { 493 err |= __copy_to_user(frame->extramask, &set->sig[1], 494 sizeof(frame->extramask)); 495 } 496 497 if (err == 0) 498 err = setup_return(regs, ka, frame->retcode, frame, usig); 499 500 return err; 501 } 502 503 static int 504 setup_rt_frame(int usig, struct k_sigaction *ka, siginfo_t *info, 505 sigset_t *set, struct pt_regs *regs) 506 { 507 struct rt_sigframe __user *frame = get_sigframe(ka, regs, sizeof(*frame)); 508 stack_t stack; 509 int err = 0; 510 511 if (!frame) 512 return 1; 513 514 __put_user_error(&frame->info, &frame->pinfo, err); 515 __put_user_error(&frame->uc, &frame->puc, err); 516 err |= copy_siginfo_to_user(&frame->info, info); 517 518 __put_user_error(0, &frame->uc.uc_flags, err); 519 __put_user_error(NULL, &frame->uc.uc_link, err); 520 521 memset(&stack, 0, sizeof(stack)); 522 stack.ss_sp = (void __user *)current->sas_ss_sp; 523 stack.ss_flags = sas_ss_flags(regs->ARM_sp); 524 stack.ss_size = current->sas_ss_size; 525 err |= __copy_to_user(&frame->uc.uc_stack, &stack, sizeof(stack)); 526 527 err |= setup_sigcontext(&frame->uc.uc_mcontext, &frame->aux, 528 regs, set->sig[0]); 529 err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set)); 530 531 if (err == 0) 532 err = setup_return(regs, ka, frame->retcode, frame, usig); 533 534 if (err == 0) { 535 /* 536 * For realtime signals we must also set the second and third 537 * arguments for the signal handler. 538 * -- Peter Maydell <pmaydell@chiark.greenend.org.uk> 2000-12-06 539 */ 540 regs->ARM_r1 = (unsigned long)&frame->info; 541 regs->ARM_r2 = (unsigned long)&frame->uc; 542 } 543 544 return err; 545 } 546 547 static inline void restart_syscall(struct pt_regs *regs) 548 { 549 regs->ARM_r0 = regs->ARM_ORIG_r0; 550 regs->ARM_pc -= thumb_mode(regs) ? 2 : 4; 551 } 552 553 /* 554 * OK, we're invoking a handler 555 */ 556 static void 557 handle_signal(unsigned long sig, struct k_sigaction *ka, 558 siginfo_t *info, sigset_t *oldset, 559 struct pt_regs * regs, int syscall) 560 { 561 struct thread_info *thread = current_thread_info(); 562 struct task_struct *tsk = current; 563 int usig = sig; 564 int ret; 565 566 /* 567 * If we were from a system call, check for system call restarting... 568 */ 569 if (syscall) { 570 switch (regs->ARM_r0) { 571 case -ERESTART_RESTARTBLOCK: 572 case -ERESTARTNOHAND: 573 regs->ARM_r0 = -EINTR; 574 break; 575 case -ERESTARTSYS: 576 if (!(ka->sa.sa_flags & SA_RESTART)) { 577 regs->ARM_r0 = -EINTR; 578 break; 579 } 580 /* fallthrough */ 581 case -ERESTARTNOINTR: 582 restart_syscall(regs); 583 } 584 } 585 586 /* 587 * translate the signal 588 */ 589 if (usig < 32 && thread->exec_domain && thread->exec_domain->signal_invmap) 590 usig = thread->exec_domain->signal_invmap[usig]; 591 592 /* 593 * Set up the stack frame 594 */ 595 if (ka->sa.sa_flags & SA_SIGINFO) 596 ret = setup_rt_frame(usig, ka, info, oldset, regs); 597 else 598 ret = setup_frame(usig, ka, oldset, regs); 599 600 /* 601 * Check that the resulting registers are actually sane. 602 */ 603 ret |= !valid_user_regs(regs); 604 605 if (ret != 0) { 606 force_sigsegv(sig, tsk); 607 return; 608 } 609 610 /* 611 * Block the signal if we were successful. 612 */ 613 spin_lock_irq(&tsk->sighand->siglock); 614 sigorsets(&tsk->blocked, &tsk->blocked, 615 &ka->sa.sa_mask); 616 if (!(ka->sa.sa_flags & SA_NODEFER)) 617 sigaddset(&tsk->blocked, sig); 618 recalc_sigpending(); 619 spin_unlock_irq(&tsk->sighand->siglock); 620 621 } 622 623 /* 624 * Note that 'init' is a special process: it doesn't get signals it doesn't 625 * want to handle. Thus you cannot kill init even with a SIGKILL even by 626 * mistake. 627 * 628 * Note that we go through the signals twice: once to check the signals that 629 * the kernel can handle, and then we build all the user-level signal handling 630 * stack-frames in one go after that. 631 */ 632 static int do_signal(sigset_t *oldset, struct pt_regs *regs, int syscall) 633 { 634 struct k_sigaction ka; 635 siginfo_t info; 636 int signr; 637 638 /* 639 * We want the common case to go fast, which 640 * is why we may in certain cases get here from 641 * kernel mode. Just return without doing anything 642 * if so. 643 */ 644 if (!user_mode(regs)) 645 return 0; 646 647 if (try_to_freeze()) 648 goto no_signal; 649 650 if (current->ptrace & PT_SINGLESTEP) 651 ptrace_cancel_bpt(current); 652 653 signr = get_signal_to_deliver(&info, &ka, regs, NULL); 654 if (signr > 0) { 655 handle_signal(signr, &ka, &info, oldset, regs, syscall); 656 if (current->ptrace & PT_SINGLESTEP) 657 ptrace_set_bpt(current); 658 return 1; 659 } 660 661 no_signal: 662 /* 663 * No signal to deliver to the process - restart the syscall. 664 */ 665 if (syscall) { 666 if (regs->ARM_r0 == -ERESTART_RESTARTBLOCK) { 667 if (thumb_mode(regs)) { 668 regs->ARM_r7 = __NR_restart_syscall; 669 regs->ARM_pc -= 2; 670 } else { 671 u32 __user *usp; 672 673 regs->ARM_sp -= 12; 674 usp = (u32 __user *)regs->ARM_sp; 675 676 put_user(regs->ARM_pc, &usp[0]); 677 /* swi __NR_restart_syscall */ 678 put_user(0xef000000 | __NR_restart_syscall, &usp[1]); 679 /* ldr pc, [sp], #12 */ 680 put_user(0xe49df00c, &usp[2]); 681 682 flush_icache_range((unsigned long)usp, 683 (unsigned long)(usp + 3)); 684 685 regs->ARM_pc = regs->ARM_sp + 4; 686 } 687 } 688 if (regs->ARM_r0 == -ERESTARTNOHAND || 689 regs->ARM_r0 == -ERESTARTSYS || 690 regs->ARM_r0 == -ERESTARTNOINTR) { 691 restart_syscall(regs); 692 } 693 } 694 if (current->ptrace & PT_SINGLESTEP) 695 ptrace_set_bpt(current); 696 return 0; 697 } 698 699 asmlinkage void 700 do_notify_resume(struct pt_regs *regs, unsigned int thread_flags, int syscall) 701 { 702 if (thread_flags & _TIF_SIGPENDING) 703 do_signal(¤t->blocked, regs, syscall); 704 } 705