aboutsummaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
-rw-r--r--arch/arm/kernel/signal.c90
1 files changed, 53 insertions, 37 deletions
diff --git a/arch/arm/kernel/signal.c b/arch/arm/kernel/signal.c
index cb8398317644..0340224cf73c 100644
--- a/arch/arm/kernel/signal.c
+++ b/arch/arm/kernel/signal.c
@@ -597,19 +597,13 @@ setup_rt_frame(int usig, struct k_sigaction *ka, siginfo_t *info,
597 return err; 597 return err;
598} 598}
599 599
600static inline void setup_syscall_restart(struct pt_regs *regs)
601{
602 regs->ARM_r0 = regs->ARM_ORIG_r0;
603 regs->ARM_pc -= thumb_mode(regs) ? 2 : 4;
604}
605
606/* 600/*
607 * OK, we're invoking a handler 601 * OK, we're invoking a handler
608 */ 602 */
609static int 603static int
610handle_signal(unsigned long sig, struct k_sigaction *ka, 604handle_signal(unsigned long sig, struct k_sigaction *ka,
611 siginfo_t *info, sigset_t *oldset, 605 siginfo_t *info, sigset_t *oldset,
612 struct pt_regs * regs, int syscall) 606 struct pt_regs * regs)
613{ 607{
614 struct thread_info *thread = current_thread_info(); 608 struct thread_info *thread = current_thread_info();
615 struct task_struct *tsk = current; 609 struct task_struct *tsk = current;
@@ -617,26 +611,6 @@ handle_signal(unsigned long sig, struct k_sigaction *ka,
617 int ret; 611 int ret;
618 612
619 /* 613 /*
620 * If we were from a system call, check for system call restarting...
621 */
622 if (syscall) {
623 switch (regs->ARM_r0) {
624 case -ERESTART_RESTARTBLOCK:
625 case -ERESTARTNOHAND:
626 regs->ARM_r0 = -EINTR;
627 break;
628 case -ERESTARTSYS:
629 if (!(ka->sa.sa_flags & SA_RESTART)) {
630 regs->ARM_r0 = -EINTR;
631 break;
632 }
633 /* fallthrough */
634 case -ERESTARTNOINTR:
635 setup_syscall_restart(regs);
636 }
637 }
638
639 /*
640 * translate the signal 614 * translate the signal
641 */ 615 */
642 if (usig < 32 && thread->exec_domain && thread->exec_domain->signal_invmap) 616 if (usig < 32 && thread->exec_domain && thread->exec_domain->signal_invmap)
@@ -685,6 +659,7 @@ handle_signal(unsigned long sig, struct k_sigaction *ka,
685 */ 659 */
686static void do_signal(struct pt_regs *regs, int syscall) 660static void do_signal(struct pt_regs *regs, int syscall)
687{ 661{
662 unsigned int retval = 0, continue_addr = 0, restart_addr = 0;
688 struct k_sigaction ka; 663 struct k_sigaction ka;
689 siginfo_t info; 664 siginfo_t info;
690 int signr; 665 int signr;
@@ -698,18 +673,61 @@ static void do_signal(struct pt_regs *regs, int syscall)
698 if (!user_mode(regs)) 673 if (!user_mode(regs))
699 return; 674 return;
700 675
676 /*
677 * If we were from a system call, check for system call restarting...
678 */
679 if (syscall) {
680 continue_addr = regs->ARM_pc;
681 restart_addr = continue_addr - (thumb_mode(regs) ? 2 : 4);
682 retval = regs->ARM_r0;
683
684 /*
685 * Prepare for system call restart. We do this here so that a
686 * debugger will see the already changed PSW.
687 */
688 switch (retval) {
689 case -ERESTARTNOHAND:
690 case -ERESTARTSYS:
691 case -ERESTARTNOINTR:
692 regs->ARM_r0 = regs->ARM_ORIG_r0;
693 regs->ARM_pc = restart_addr;
694 break;
695 case -ERESTART_RESTARTBLOCK:
696 regs->ARM_r0 = -EINTR;
697 break;
698 }
699 }
700
701 if (try_to_freeze()) 701 if (try_to_freeze())
702 goto no_signal; 702 goto no_signal;
703 703
704 /*
705 * Get the signal to deliver. When running under ptrace, at this
706 * point the debugger may change all our registers ...
707 */
704 signr = get_signal_to_deliver(&info, &ka, regs, NULL); 708 signr = get_signal_to_deliver(&info, &ka, regs, NULL);
705 if (signr > 0) { 709 if (signr > 0) {
706 sigset_t *oldset; 710 sigset_t *oldset;
707 711
712 /*
713 * Depending on the signal settings we may need to revert the
714 * decision to restart the system call. But skip this if a
715 * debugger has chosen to restart at a different PC.
716 */
717 if (regs->ARM_pc == restart_addr) {
718 if (retval == -ERESTARTNOHAND
719 || (retval == -ERESTARTSYS
720 && !(ka.sa.sa_flags & SA_RESTART))) {
721 regs->ARM_r0 = -EINTR;
722 regs->ARM_pc = continue_addr;
723 }
724 }
725
708 if (test_thread_flag(TIF_RESTORE_SIGMASK)) 726 if (test_thread_flag(TIF_RESTORE_SIGMASK))
709 oldset = &current->saved_sigmask; 727 oldset = &current->saved_sigmask;
710 else 728 else
711 oldset = &current->blocked; 729 oldset = &current->blocked;
712 if (handle_signal(signr, &ka, &info, oldset, regs, syscall) == 0) { 730 if (handle_signal(signr, &ka, &info, oldset, regs) == 0) {
713 /* 731 /*
714 * A signal was successfully delivered; the saved 732 * A signal was successfully delivered; the saved
715 * sigmask will have been stored in the signal frame, 733 * sigmask will have been stored in the signal frame,
@@ -723,11 +741,14 @@ static void do_signal(struct pt_regs *regs, int syscall)
723 } 741 }
724 742
725 no_signal: 743 no_signal:
726 /*
727 * No signal to deliver to the process - restart the syscall.
728 */
729 if (syscall) { 744 if (syscall) {
730 if (regs->ARM_r0 == -ERESTART_RESTARTBLOCK) { 745 /*
746 * Handle restarting a different system call. As above,
747 * if a debugger has chosen to restart at a different PC,
748 * ignore the restart.
749 */
750 if (retval == -ERESTART_RESTARTBLOCK
751 && regs->ARM_pc == continue_addr) {
731 if (thumb_mode(regs)) { 752 if (thumb_mode(regs)) {
732 regs->ARM_r7 = __NR_restart_syscall - __NR_SYSCALL_BASE; 753 regs->ARM_r7 = __NR_restart_syscall - __NR_SYSCALL_BASE;
733 regs->ARM_pc -= 2; 754 regs->ARM_pc -= 2;
@@ -750,11 +771,6 @@ static void do_signal(struct pt_regs *regs, int syscall)
750#endif 771#endif
751 } 772 }
752 } 773 }
753 if (regs->ARM_r0 == -ERESTARTNOHAND ||
754 regs->ARM_r0 == -ERESTARTSYS ||
755 regs->ARM_r0 == -ERESTARTNOINTR) {
756 setup_syscall_restart(regs);
757 }
758 774
759 /* If there's no signal to deliver, we just put the saved sigmask 775 /* If there's no signal to deliver, we just put the saved sigmask
760 * back. 776 * back.