예제 #1
0
/*
 * Note that 'init' is a special process: it doesn't get signals it doesn't
 * want to handle. Thus you cannot kill init even with a SIGKILL even by
 * mistake.
 */
int do_signal(sigset_t *oldset, struct pt_regs *regs)
{
	siginfo_t info;
	int signr;
	struct k_sigaction ka;

	/*
	 * If the current thread is 32 bit - invoke the
	 * 32 bit signal handling code
	 */
	if (test_thread_flag(TIF_32BIT))
		return do_signal32(oldset, regs);

	if (!oldset)
		oldset = &current->blocked;

	signr = get_signal_to_deliver(&info, &ka, regs, NULL);
	if (signr > 0) {
		/* Whee!  Actually deliver the signal.  */
		if (TRAP(regs) == 0x0C00)
			syscall_restart(regs, &ka);

		/*
		 * Reenable the DABR before delivering the signal to
		 * user space. The DABR will have been cleared if it
		 * triggered inside the kernel.
		 */
		if (current->thread.dabr)
			set_dabr(current->thread.dabr);

		return handle_signal(signr, &ka, &info, oldset, regs);
	}

	if (TRAP(regs) == 0x0C00) {	/* System Call! */
		if ((int)regs->result == -ERESTARTNOHAND ||
		    (int)regs->result == -ERESTARTSYS ||
		    (int)regs->result == -ERESTARTNOINTR) {
			regs->gpr[3] = regs->orig_gpr3;
			regs->nip -= 4; /* Back up & retry system call */
			regs->result = 0;
		} else if ((int)regs->result == -ERESTART_RESTARTBLOCK) {
			regs->gpr[0] = __NR_restart_syscall;
			regs->nip -= 4;
			regs->result = 0;
		}
	}

	return 0;
}
예제 #2
0
/*
 * Note that 'init' is a special process: it doesn't get signals it doesn't
 * want to handle. Thus you cannot kill init even with a SIGKILL even by
 * mistake.
 *
 * Note that we go through the signals twice: once to check the signals that
 * the kernel can handle, and then we build all the user-level signal handling
 * stack-frames in one go after that.
 *
 * "r0" and "r19" are the registers we need to restore for system call
 * restart. "r0" is also used as an indicator whether we can restart at
 * all (if we get here from anything but a syscall return, it will be 0)
 */
static int
do_signal(sigset_t *oldset, struct pt_regs * regs, struct switch_stack * sw,
	  unsigned long r0, unsigned long r19)
{
	siginfo_t info;
	int signr;
	unsigned long single_stepping = ptrace_cancel_bpt(current);
	struct k_sigaction ka;

	if (!oldset)
		oldset = &current->blocked;

	/* This lets the debugger run, ... */
	signr = get_signal_to_deliver(&info, &ka, regs, NULL);
	/* ... so re-check the single stepping. */
	single_stepping |= ptrace_cancel_bpt(current);

	if (signr > 0) {
		/* Whee!  Actually deliver the signal.  */
		if (r0) syscall_restart(r0, r19, regs, &ka);
		handle_signal(signr, &ka, &info, oldset, regs, sw);
		if (single_stepping) 
			ptrace_set_bpt(current); /* re-set bpt */
		return 1;
	}

	if (r0) {
	  	switch (regs->r0) {
		case ERESTARTNOHAND:
		case ERESTARTSYS:
		case ERESTARTNOINTR:
			/* Reset v0 and a3 and replay syscall.  */
			regs->r0 = r0;
			regs->r19 = r19;
			regs->pc -= 4;
			break;
		case ERESTART_RESTARTBLOCK:
			/* Force v0 to the restart syscall and reply.  */
			regs->r0 = __NR_restart_syscall;
			regs->pc -= 4;
			break;
		}
	}
	if (single_stepping)
		ptrace_set_bpt(current);	/* re-set breakpoint */

	return 0;
}
예제 #3
0
/* Note that 'init' is a special process: it doesn't get signals it doesn't
 * want to handle. Thus you cannot kill init even with a SIGKILL even by
 * mistake.
 */
static int do_signal(sigset_t *oldset, struct pt_regs * regs,
		     unsigned long orig_i0, int restart_syscall)
{
	siginfo_t info;
	struct signal_deliver_cookie cookie;
	struct k_sigaction ka;
	int signr;
	
	cookie.restart_syscall = restart_syscall;
	cookie.orig_i0 = orig_i0;

	if (!oldset)
		oldset = &current->blocked;

#ifdef CONFIG_SPARC32_COMPAT
	if (test_thread_flag(TIF_32BIT)) {
		extern int do_signal32(sigset_t *, struct pt_regs *,
				       unsigned long, int);
		return do_signal32(oldset, regs, orig_i0,
				   cookie.restart_syscall);
	}
#endif	

	signr = get_signal_to_deliver(&info, &ka, regs, &cookie);
	if (signr > 0) {
		if (cookie.restart_syscall)
			syscall_restart(orig_i0, regs, &ka.sa);
		handle_signal(signr, &ka, &info, oldset, regs);
		return 1;
	}
	if (cookie.restart_syscall &&
	    (regs->u_regs[UREG_I0] == ERESTARTNOHAND ||
	     regs->u_regs[UREG_I0] == ERESTARTSYS ||
	     regs->u_regs[UREG_I0] == ERESTARTNOINTR)) {
		/* replay the system call when we are done */
		regs->u_regs[UREG_I0] = cookie.orig_i0;
		regs->tpc -= 4;
		regs->tnpc -= 4;
	}
	if (cookie.restart_syscall &&
	    regs->u_regs[UREG_I0] == ERESTART_RESTARTBLOCK) {
		regs->u_regs[UREG_G1] = __NR_restart_syscall;
		regs->tpc -= 4;
		regs->tnpc -= 4;
	}
	return 0;
}
예제 #4
0
/*
 * Note that 'init' is a special process: it doesn't get signals it doesn't
 * want to handle. Thus you cannot kill init even with a SIGKILL even by
 * mistake.
 *
 * Note that we go through the signals twice: once to check the signals that
 * the kernel can handle, and then we build all the user-level signal handling
 * stack-frames in one go after that.
 *
 * "r0" and "r19" are the registers we need to restore for system call
 * restart. "r0" is also used as an indicator whether we can restart at
 * all (if we get here from anything but a syscall return, it will be 0)
 */
static void
do_signal(struct pt_regs *regs, unsigned long r0, unsigned long r19)
{
	siginfo_t info;
	int signr;
	unsigned long single_stepping = ptrace_cancel_bpt(current);
	struct k_sigaction ka;

	/* This lets the debugger run, ... */
	signr = get_signal_to_deliver(&info, &ka, regs, NULL);

	/* ... so re-check the single stepping. */
	single_stepping |= ptrace_cancel_bpt(current);

	if (signr > 0) {
		/* Whee!  Actually deliver the signal.  */
		if (r0)
			syscall_restart(r0, r19, regs, &ka);
		handle_signal(signr, &ka, &info, regs);
		if (single_stepping) 
			ptrace_set_bpt(current); /* re-set bpt */
		return;
	}

	if (r0) {
	  	switch (regs->r0) {
		case ERESTARTNOHAND:
		case ERESTARTSYS:
		case ERESTARTNOINTR:
			/* Reset v0 and a3 and replay syscall.  */
			regs->r0 = r0;
			regs->r19 = r19;
			regs->pc -= 4;
			break;
		case ERESTART_RESTARTBLOCK:
			/* Force v0 to the restart syscall and reply.  */
			regs->r0 = __NR_restart_syscall;
			regs->pc -= 4;
			break;
		}
	}

	/* If there's no signal to deliver, we just restore the saved mask.  */
	restore_saved_sigmask();
	if (single_stepping)
		ptrace_set_bpt(current);	/* re-set breakpoint */
}
예제 #5
0
int
do_signal(sigset_t *oldset, struct pt_regs *regs)
{
	siginfo_t info;
	int signr;

	/*
	 * If the current thread is 32 bit - invoke the
	 * 32 bit signal handling code
	 */
	if (current->thread.flags & PPC_FLAG_32BIT)
		return do_signal32(oldset, regs);

        if (!oldset)
		oldset = &current->blocked;

	signr = get_signal_to_deliver(&info, regs);
	if (signr > 0) {
		struct k_sigaction *ka = &current->sig->action[signr-1];

		/* Whee!  Actually deliver the signal.  */
		if (regs->trap == 0x0C00)
			syscall_restart(regs, ka);
		handle_signal(signr, ka, &info, oldset, regs);
		return 1;
	}

	if (regs->trap == 0x0C00 /* System Call! */ &&
	    ((int)regs->result == -ERESTARTNOHAND ||
	     (int)regs->result == -ERESTARTSYS ||
	     (int)regs->result == -ERESTARTNOINTR)) {
		regs->gpr[3] = regs->orig_gpr3;
		regs->nip -= 4;		/* Back up & retry system call */
		regs->result = 0;
	}

	return 0;
}
예제 #6
0
/* Note that 'init' is a special process: it doesn't get signals it doesn't
 * want to handle. Thus you cannot kill init even with a SIGKILL even by
 * mistake.
 */
static void do_signal(struct pt_regs *regs, unsigned long orig_i0)
{
	struct k_sigaction ka;
	int restart_syscall;
	sigset_t *oldset;
	siginfo_t info;
	int signr;

	if (pt_regs_is_syscall(regs) && (regs->psr & PSR_C))
		restart_syscall = 1;
	else
		restart_syscall = 0;

	if (test_thread_flag(TIF_RESTORE_SIGMASK))
		oldset = &current->saved_sigmask;
	else
		oldset = &current->blocked;

	signr = get_signal_to_deliver(&info, &ka, regs, NULL);

	/* If the debugger messes with the program counter, it clears
	 * the software "in syscall" bit, directing us to not perform
	 * a syscall restart.
	 */
	if (restart_syscall && !pt_regs_is_syscall(regs))
		restart_syscall = 0;

	if (signr > 0) {
		if (restart_syscall)
			syscall_restart(orig_i0, regs, &ka.sa);
		if (handle_signal(signr, &ka, &info, oldset, regs) == 0) {
			/* a signal was successfully delivered; the saved
			 * sigmask will have been stored in the signal frame,
			 * and will be restored by sigreturn, so we can simply
			 * clear the TIF_RESTORE_SIGMASK flag.
			 */
			if (test_thread_flag(TIF_RESTORE_SIGMASK))
				clear_thread_flag(TIF_RESTORE_SIGMASK);
		}
		return;
	}
	if (restart_syscall &&
	    (regs->u_regs[UREG_I0] == ERESTARTNOHAND ||
	     regs->u_regs[UREG_I0] == ERESTARTSYS ||
	     regs->u_regs[UREG_I0] == ERESTARTNOINTR)) {
		/* replay the system call when we are done */
		regs->u_regs[UREG_I0] = orig_i0;
		regs->pc -= 4;
		regs->npc -= 4;
		pt_regs_clear_syscall(regs);
	}
	if (restart_syscall &&
	    regs->u_regs[UREG_I0] == ERESTART_RESTARTBLOCK) {
		regs->u_regs[UREG_G1] = __NR_restart_syscall;
		regs->pc -= 4;
		regs->npc -= 4;
		pt_regs_clear_syscall(regs);
	}

	/* if there's no signal to deliver, we just put the saved sigmask
	 * back
	 */
	if (test_thread_flag(TIF_RESTORE_SIGMASK)) {
		clear_thread_flag(TIF_RESTORE_SIGMASK);
		sigprocmask(SIG_SETMASK, &current->saved_sigmask, NULL);
	}
}
예제 #7
0
/* Note that 'init' is a special process: it doesn't get signals it doesn't
 * want to handle. Thus you cannot kill init even with a SIGKILL even by
 * mistake.
 */
static void do_signal(struct pt_regs *regs, unsigned long orig_i0, int restart_syscall)
{
	siginfo_t info;
	struct signal_deliver_cookie cookie;
	struct k_sigaction ka;
	int signr;
	sigset_t *oldset;
	
	cookie.restart_syscall = restart_syscall;
	cookie.orig_i0 = orig_i0;

	if (test_thread_flag(TIF_RESTORE_SIGMASK))
		oldset = &current->saved_sigmask;
	else
		oldset = &current->blocked;

#ifdef CONFIG_SPARC32_COMPAT
	if (test_thread_flag(TIF_32BIT)) {
		extern void do_signal32(sigset_t *, struct pt_regs *,
					unsigned long, int);
		do_signal32(oldset, regs, orig_i0,
			    cookie.restart_syscall);
		return;
	}
#endif	

	signr = get_signal_to_deliver(&info, &ka, regs, &cookie);
	if (signr > 0) {
		if (cookie.restart_syscall)
			syscall_restart(orig_i0, regs, &ka.sa);
		handle_signal(signr, &ka, &info, oldset, regs);

		/* a signal was successfully delivered; the saved
		 * sigmask will have been stored in the signal frame,
		 * and will be restored by sigreturn, so we can simply
		 * clear the TIF_RESTORE_SIGMASK flag.
		 */
		if (test_thread_flag(TIF_RESTORE_SIGMASK))
			clear_thread_flag(TIF_RESTORE_SIGMASK);
		return;
	}
	if (cookie.restart_syscall &&
	    (regs->u_regs[UREG_I0] == ERESTARTNOHAND ||
	     regs->u_regs[UREG_I0] == ERESTARTSYS ||
	     regs->u_regs[UREG_I0] == ERESTARTNOINTR)) {
		/* replay the system call when we are done */
		regs->u_regs[UREG_I0] = cookie.orig_i0;
		regs->tpc -= 4;
		regs->tnpc -= 4;
	}
	if (cookie.restart_syscall &&
	    regs->u_regs[UREG_I0] == ERESTART_RESTARTBLOCK) {
		regs->u_regs[UREG_G1] = __NR_restart_syscall;
		regs->tpc -= 4;
		regs->tnpc -= 4;
	}

	/* if there's no signal to deliver, we just put the saved sigmask
	 * back
	 */
	if (test_thread_flag(TIF_RESTORE_SIGMASK)) {
		clear_thread_flag(TIF_RESTORE_SIGMASK);
		sigprocmask(SIG_SETMASK, &current->saved_sigmask, NULL);
	}
}
예제 #8
0
/*
 * Note that 'init' is a special process: it doesn't get signals it doesn't
 * want to handle. Thus you cannot kill init even with a SIGKILL even by
 * mistake.
 *
 * Note that we go through the signals twice: once to check the signals that
 * the kernel can handle, and then we build all the user-level signal handling
 * stack-frames in one go after that.
 *
 * "r0" and "r19" are the registers we need to restore for system call
 * restart. "r0" is also used as an indicator whether we can restart at
 * all (if we get here from anything but a syscall return, it will be 0)
 */
static void
do_signal(struct pt_regs * regs, struct switch_stack * sw,
	  unsigned long r0, unsigned long r19)
{
	siginfo_t info;
	int signr;
	unsigned long single_stepping = ptrace_cancel_bpt(current);
	struct k_sigaction ka;
	sigset_t *oldset;

	if (test_thread_flag(TIF_RESTORE_SIGMASK))
		oldset = &current->saved_sigmask;
	else
		oldset = &current->blocked;

	/* This lets the debugger run, ... */
	signr = get_signal_to_deliver(&info, &ka, regs, NULL);

	/* ... so re-check the single stepping. */
	single_stepping |= ptrace_cancel_bpt(current);

	if (signr > 0) {
		/* Whee!  Actually deliver the signal.  */
		if (r0)
			syscall_restart(r0, r19, regs, &ka);
		if (handle_signal(signr, &ka, &info, oldset, regs, sw) == 0) {
			/* A signal was successfully delivered, and the
			   saved sigmask was stored on the signal frame,
			   and will be restored by sigreturn.  So we can
			   simply clear the restore sigmask flag.  */
			if (test_thread_flag(TIF_RESTORE_SIGMASK))
				clear_thread_flag(TIF_RESTORE_SIGMASK);
		}
		if (single_stepping) 
			ptrace_set_bpt(current); /* re-set bpt */
		return;
	}

	if (r0) {
	  	switch (regs->r0) {
		case ERESTARTNOHAND:
		case ERESTARTSYS:
		case ERESTARTNOINTR:
			/* Reset v0 and a3 and replay syscall.  */
			regs->r0 = r0;
			regs->r19 = r19;
			regs->pc -= 4;
			break;
		case ERESTART_RESTARTBLOCK:
			/* Force v0 to the restart syscall and reply.  */
			regs->r0 = __NR_restart_syscall;
			regs->pc -= 4;
			break;
		}
	}

	/* If there's no signal to deliver, we just restore the saved mask.  */
	if (test_thread_flag(TIF_RESTORE_SIGMASK)) {
		clear_thread_flag(TIF_RESTORE_SIGMASK);
		sigprocmask(SIG_SETMASK, &current->saved_sigmask, NULL);
	}

	if (single_stepping)
		ptrace_set_bpt(current);	/* re-set breakpoint */
}
/* Note that 'init' is a special process: it doesn't get signals it doesn't
 * want to handle. Thus you cannot kill init even with a SIGKILL even by
 * mistake.
 */
static void do_signal(struct pt_regs *regs, unsigned long orig_i0)
{
	struct k_sigaction ka;
	int restart_syscall;
	sigset_t *oldset;
	siginfo_t info;
	int signr;

	/* It's a lot of work and synchronization to add a new ptrace
	 * register for GDB to save and restore in order to get
	 * orig_i0 correct for syscall restarts when debugging.
	 *
	 * Although it should be the case that most of the global
	 * registers are volatile across a system call, glibc already
	 * depends upon that fact that we preserve them.  So we can't
	 * just use any global register to save away the orig_i0 value.
	 *
	 * In particular %g2, %g3, %g4, and %g5 are all assumed to be
	 * preserved across a system call trap by various pieces of
	 * code in glibc.
	 *
	 * %g7 is used as the "thread register".   %g6 is not used in
	 * any fixed manner.  %g6 is used as a scratch register and
	 * a compiler temporary, but it's value is never used across
	 * a system call.  Therefore %g6 is usable for orig_i0 storage.
	 */
	if (pt_regs_is_syscall(regs) && (regs->psr & PSR_C))
		regs->u_regs[UREG_G6] = orig_i0;

	if (test_thread_flag(TIF_RESTORE_SIGMASK))
		oldset = &current->saved_sigmask;
	else
		oldset = &current->blocked;

	signr = get_signal_to_deliver(&info, &ka, regs, NULL);

	/* If the debugger messes with the program counter, it clears
	 * the software "in syscall" bit, directing us to not perform
	 * a syscall restart.
	 */
	restart_syscall = 0;
	if (pt_regs_is_syscall(regs) && (regs->psr & PSR_C)) {
		restart_syscall = 1;
		orig_i0 = regs->u_regs[UREG_G6];
	}


	if (signr > 0) {
		if (restart_syscall)
			syscall_restart(orig_i0, regs, &ka.sa);
		if (handle_signal(signr, &ka, &info, oldset, regs) == 0) {
			/* a signal was successfully delivered; the saved
			 * sigmask will have been stored in the signal frame,
			 * and will be restored by sigreturn, so we can simply
			 * clear the TIF_RESTORE_SIGMASK flag.
			 */
			if (test_thread_flag(TIF_RESTORE_SIGMASK))
				clear_thread_flag(TIF_RESTORE_SIGMASK);
		}
		return;
	}
	if (restart_syscall &&
	    (regs->u_regs[UREG_I0] == ERESTARTNOHAND ||
	     regs->u_regs[UREG_I0] == ERESTARTSYS ||
	     regs->u_regs[UREG_I0] == ERESTARTNOINTR)) {
		/* replay the system call when we are done */
		regs->u_regs[UREG_I0] = orig_i0;
		regs->pc -= 4;
		regs->npc -= 4;
		pt_regs_clear_syscall(regs);
	}
	if (restart_syscall &&
	    regs->u_regs[UREG_I0] == ERESTART_RESTARTBLOCK) {
		regs->u_regs[UREG_G1] = __NR_restart_syscall;
		regs->pc -= 4;
		regs->npc -= 4;
		pt_regs_clear_syscall(regs);
	}

	/* if there's no signal to deliver, we just put the saved sigmask
	 * back
	 */
	if (test_thread_flag(TIF_RESTORE_SIGMASK)) {
		clear_thread_flag(TIF_RESTORE_SIGMASK);
		sigprocmask(SIG_SETMASK, &current->saved_sigmask, NULL);
	}
}
예제 #10
0
/* Note that 'init' is a special process: it doesn't get signals it doesn't
 * want to handle. Thus you cannot kill init even with a SIGKILL even by
 * mistake.
 */
static void do_signal(struct pt_regs *regs, unsigned long orig_i0)
{
	struct k_sigaction ka;
	int restart_syscall;
	sigset_t *oldset;
	siginfo_t info;
	int signr;
	
	if (pt_regs_is_syscall(regs) &&
	    (regs->tstate & (TSTATE_XCARRY | TSTATE_ICARRY))) {
		restart_syscall = 1;
	} else
		restart_syscall = 0;

	if (current_thread_info()->status & TS_RESTORE_SIGMASK)
		oldset = &current->saved_sigmask;
	else
		oldset = &current->blocked;

#ifdef CONFIG_COMPAT
	if (test_thread_flag(TIF_32BIT)) {
		extern void do_signal32(sigset_t *, struct pt_regs *,
					int restart_syscall,
					unsigned long orig_i0);
		do_signal32(oldset, regs, restart_syscall, orig_i0);
		return;
	}
#endif	

	signr = get_signal_to_deliver(&info, &ka, regs, NULL);

	/* If the debugger messes with the program counter, it clears
	 * the software "in syscall" bit, directing us to not perform
	 * a syscall restart.
	 */
	if (restart_syscall && !pt_regs_is_syscall(regs))
		restart_syscall = 0;

	if (signr > 0) {
		if (restart_syscall)
			syscall_restart(orig_i0, regs, &ka.sa);
		handle_signal(signr, &ka, &info, oldset, regs);

		/* A signal was successfully delivered; the saved
		 * sigmask will have been stored in the signal frame,
		 * and will be restored by sigreturn, so we can simply
		 * clear the TS_RESTORE_SIGMASK flag.
		 */
		current_thread_info()->status &= ~TS_RESTORE_SIGMASK;

		tracehook_signal_handler(signr, &info, &ka, regs, 0);
		return;
	}
	if (restart_syscall &&
	    (regs->u_regs[UREG_I0] == ERESTARTNOHAND ||
	     regs->u_regs[UREG_I0] == ERESTARTSYS ||
	     regs->u_regs[UREG_I0] == ERESTARTNOINTR)) {
		/* replay the system call when we are done */
		regs->u_regs[UREG_I0] = orig_i0;
		regs->tpc -= 4;
		regs->tnpc -= 4;
	}
	if (restart_syscall &&
	    regs->u_regs[UREG_I0] == ERESTART_RESTARTBLOCK) {
		regs->u_regs[UREG_G1] = __NR_restart_syscall;
		regs->tpc -= 4;
		regs->tnpc -= 4;
	}

	/* If there's no signal to deliver, we just put the saved sigmask
	 * back
	 */
	if (current_thread_info()->status & TS_RESTORE_SIGMASK) {
		current_thread_info()->status &= ~TS_RESTORE_SIGMASK;
		sigprocmask(SIG_SETMASK, &current->saved_sigmask, NULL);
	}
}
예제 #11
0
파일: signal_64.c 프로젝트: 24hours/linux
/* Note that 'init' is a special process: it doesn't get signals it doesn't
 * want to handle. Thus you cannot kill init even with a SIGKILL even by
 * mistake.
 */
static void do_signal(struct pt_regs *regs, unsigned long orig_i0)
{
	struct ksignal ksig;
	int restart_syscall;
	bool has_handler;
	
	/* It's a lot of work and synchronization to add a new ptrace
	 * register for GDB to save and restore in order to get
	 * orig_i0 correct for syscall restarts when debugging.
	 *
	 * Although it should be the case that most of the global
	 * registers are volatile across a system call, glibc already
	 * depends upon that fact that we preserve them.  So we can't
	 * just use any global register to save away the orig_i0 value.
	 *
	 * In particular %g2, %g3, %g4, and %g5 are all assumed to be
	 * preserved across a system call trap by various pieces of
	 * code in glibc.
	 *
	 * %g7 is used as the "thread register".   %g6 is not used in
	 * any fixed manner.  %g6 is used as a scratch register and
	 * a compiler temporary, but it's value is never used across
	 * a system call.  Therefore %g6 is usable for orig_i0 storage.
	 */
	if (pt_regs_is_syscall(regs) &&
	    (regs->tstate & (TSTATE_XCARRY | TSTATE_ICARRY)))
		regs->u_regs[UREG_G6] = orig_i0;

#ifdef CONFIG_COMPAT
	if (test_thread_flag(TIF_32BIT)) {
		extern void do_signal32(struct pt_regs *);
		do_signal32(regs);
		return;
	}
#endif	

	has_handler = get_signal(&ksig);

	restart_syscall = 0;
	if (pt_regs_is_syscall(regs) &&
	    (regs->tstate & (TSTATE_XCARRY | TSTATE_ICARRY))) {
		restart_syscall = 1;
		orig_i0 = regs->u_regs[UREG_G6];
	}

	if (has_handler) {
		if (restart_syscall)
			syscall_restart(orig_i0, regs, &ksig.ka.sa);
		signal_setup_done(setup_rt_frame(&ksig, regs), &ksig, 0);
	} else {
		if (restart_syscall) {
			switch (regs->u_regs[UREG_I0]) {
			case ERESTARTNOHAND:
	     		case ERESTARTSYS:
			case ERESTARTNOINTR:
				/* replay the system call when we are done */
				regs->u_regs[UREG_I0] = orig_i0;
				regs->tpc -= 4;
				regs->tnpc -= 4;
				pt_regs_clear_syscall(regs);
			case ERESTART_RESTARTBLOCK:
				regs->u_regs[UREG_G1] = __NR_restart_syscall;
				regs->tpc -= 4;
				regs->tnpc -= 4;
				pt_regs_clear_syscall(regs);
			}
		}
		restore_saved_sigmask();
	}
}
예제 #12
0
파일: signal_32.c 프로젝트: 1800alex/linux
/* Note that 'init' is a special process: it doesn't get signals it doesn't
 * want to handle. Thus you cannot kill init even with a SIGKILL even by
 * mistake.
 */
static void do_signal(struct pt_regs *regs, unsigned long orig_i0)
{
	struct ksignal ksig;
	int restart_syscall;
	bool has_handler;

	/* It's a lot of work and synchronization to add a new ptrace
	 * register for GDB to save and restore in order to get
	 * orig_i0 correct for syscall restarts when debugging.
	 *
	 * Although it should be the case that most of the global
	 * registers are volatile across a system call, glibc already
	 * depends upon that fact that we preserve them.  So we can't
	 * just use any global register to save away the orig_i0 value.
	 *
	 * In particular %g2, %g3, %g4, and %g5 are all assumed to be
	 * preserved across a system call trap by various pieces of
	 * code in glibc.
	 *
	 * %g7 is used as the "thread register".   %g6 is not used in
	 * any fixed manner.  %g6 is used as a scratch register and
	 * a compiler temporary, but it's value is never used across
	 * a system call.  Therefore %g6 is usable for orig_i0 storage.
	 */
	if (pt_regs_is_syscall(regs) && (regs->psr & PSR_C))
		regs->u_regs[UREG_G6] = orig_i0;

	has_handler = get_signal(&ksig);

	/* If the debugger messes with the program counter, it clears
	 * the software "in syscall" bit, directing us to not perform
	 * a syscall restart.
	 */
	restart_syscall = 0;
	if (pt_regs_is_syscall(regs) && (regs->psr & PSR_C)) {
		restart_syscall = 1;
		orig_i0 = regs->u_regs[UREG_G6];
	}

	if (has_handler) {
		if (restart_syscall)
			syscall_restart(orig_i0, regs, &ksig.ka.sa);
		handle_signal(&ksig, regs);
	} else {
		if (restart_syscall) {
			switch (regs->u_regs[UREG_I0]) {
			case ERESTARTNOHAND:
	     		case ERESTARTSYS:
			case ERESTARTNOINTR:
				/* replay the system call when we are done */
				regs->u_regs[UREG_I0] = orig_i0;
				regs->pc -= 4;
				regs->npc -= 4;
				pt_regs_clear_syscall(regs);
			case ERESTART_RESTARTBLOCK:
				regs->u_regs[UREG_G1] = __NR_restart_syscall;
				regs->pc -= 4;
				regs->npc -= 4;
				pt_regs_clear_syscall(regs);
			}
		}
		restore_saved_sigmask();
	}
}
예제 #13
0
/*
 * Note that 'init' is a special process: it doesn't get signals it doesn't
 * want to handle. Thus you cannot kill init even with a SIGKILL even by
 * mistake.
 */
int do_signal(sigset_t *oldset, struct pt_regs *regs)
{
	siginfo_t info;
	int signr;
	struct k_sigaction ka;

	/*
	 * If the current thread is 32 bit - invoke the
	 * 32 bit signal handling code
	 */
	if (test_thread_flag(TIF_32BIT))
		return do_signal32(oldset, regs);

	if (test_thread_flag(TIF_RESTORE_SIGMASK))
		oldset = &current->saved_sigmask;
	else if (!oldset)
		oldset = &current->blocked;

	signr = get_signal_to_deliver(&info, &ka, regs, NULL);
	if (signr > 0) {
		int ret;

		/* Whee!  Actually deliver the signal.  */
		if (TRAP(regs) == 0x0C00)
			syscall_restart(regs, &ka);

		/*
		 * Reenable the DABR before delivering the signal to
		 * user space. The DABR will have been cleared if it
		 * triggered inside the kernel.
		 */
		if (current->thread.dabr)
			set_dabr(current->thread.dabr);

		ret = handle_signal(signr, &ka, &info, oldset, regs);

		/* If a signal was successfully delivered, the saved sigmask is in
		   its frame, and we can clear the TIF_RESTORE_SIGMASK flag */
		if (ret && test_thread_flag(TIF_RESTORE_SIGMASK))
			clear_thread_flag(TIF_RESTORE_SIGMASK);

		return ret;
	}

	if (TRAP(regs) == 0x0C00) {	/* System Call! */
		if ((int)regs->result == -ERESTARTNOHAND ||
		    (int)regs->result == -ERESTARTSYS ||
		    (int)regs->result == -ERESTARTNOINTR) {
			regs->gpr[3] = regs->orig_gpr3;
			regs->nip -= 4; /* Back up & retry system call */
			regs->result = 0;
		} else if ((int)regs->result == -ERESTART_RESTARTBLOCK) {
			regs->gpr[0] = __NR_restart_syscall;
			regs->nip -= 4;
			regs->result = 0;
		}
	}
	/* No signal to deliver -- put the saved sigmask back */
	if (test_thread_flag(TIF_RESTORE_SIGMASK)) {
		clear_thread_flag(TIF_RESTORE_SIGMASK);
		sigprocmask(SIG_SETMASK, &current->saved_sigmask, NULL);
	}

	return 0;
}
static void do_signal(struct pt_regs *regs, unsigned long orig_i0)
{
	struct k_sigaction ka;
	int restart_syscall;
	sigset_t *oldset;
	siginfo_t info;
	int signr;
	
	if (pt_regs_is_syscall(regs) &&
	    (regs->tstate & (TSTATE_XCARRY | TSTATE_ICARRY)))
		regs->u_regs[UREG_G6] = orig_i0;

	if (current_thread_info()->status & TS_RESTORE_SIGMASK)
		oldset = &current->saved_sigmask;
	else
		oldset = &current->blocked;

#ifdef CONFIG_COMPAT
	if (test_thread_flag(TIF_32BIT)) {
		extern void do_signal32(sigset_t *, struct pt_regs *);
		do_signal32(oldset, regs);
		return;
	}
#endif	

	signr = get_signal_to_deliver(&info, &ka, regs, NULL);

	restart_syscall = 0;
	if (pt_regs_is_syscall(regs) &&
	    (regs->tstate & (TSTATE_XCARRY | TSTATE_ICARRY))) {
		restart_syscall = 1;
		orig_i0 = regs->u_regs[UREG_G6];
	}

	if (signr > 0) {
		if (restart_syscall)
			syscall_restart(orig_i0, regs, &ka.sa);
		if (handle_signal(signr, &ka, &info, oldset, regs) == 0) {
			current_thread_info()->status &= ~TS_RESTORE_SIGMASK;
		}
		return;
	}
	if (restart_syscall &&
	    (regs->u_regs[UREG_I0] == ERESTARTNOHAND ||
	     regs->u_regs[UREG_I0] == ERESTARTSYS ||
	     regs->u_regs[UREG_I0] == ERESTARTNOINTR)) {
		
		regs->u_regs[UREG_I0] = orig_i0;
		regs->tpc -= 4;
		regs->tnpc -= 4;
		pt_regs_clear_syscall(regs);
	}
	if (restart_syscall &&
	    regs->u_regs[UREG_I0] == ERESTART_RESTARTBLOCK) {
		regs->u_regs[UREG_G1] = __NR_restart_syscall;
		regs->tpc -= 4;
		regs->tnpc -= 4;
		pt_regs_clear_syscall(regs);
	}

	if (current_thread_info()->status & TS_RESTORE_SIGMASK) {
		current_thread_info()->status &= ~TS_RESTORE_SIGMASK;
		set_current_blocked(&current->saved_sigmask);
	}
}
예제 #15
0
asmlinkage int do_irix_signal(sigset_t *oldset, struct pt_regs *regs)
{
	struct k_sigaction *ka;
	siginfo_t info;

	if (!oldset)
		oldset = &current->blocked;

	for (;;) {
		unsigned long signr;

		spin_lock_irq(&current->sigmask_lock);
		signr = dequeue_signal(&current->blocked, &info);
		spin_unlock_irq(&current->sigmask_lock);

		if (!signr)
			break;

		if ((current->ptrace & PT_PTRACED) && signr != SIGKILL) {
			/* Let the debugger run.  */
			current->exit_code = signr;
			current->state = TASK_STOPPED;
			notify_parent(current, SIGCHLD);
			schedule();

			/* We're back.  Did the debugger cancel the sig?  */
			if (!(signr = current->exit_code))
				continue;
			current->exit_code = 0;

			/* The debugger continued.  Ignore SIGSTOP.  */
			if (signr == SIGSTOP)
				continue;

			/* Update the siginfo structure.  Is this good?  */
			if (signr != info.si_signo) {
				info.si_signo = signr;
				info.si_errno = 0;
				info.si_code = SI_USER;
				info.si_pid = current->p_pptr->pid;
				info.si_uid = current->p_pptr->uid;
			}

			/* If the (new) signal is now blocked, requeue it.  */
			if (sigismember(&current->blocked, signr)) {
				send_sig_info(signr, &info, current);
				continue;
			}
		}

		ka = &current->sig->action[signr-1];
		if (ka->sa.sa_handler == SIG_IGN) {
			if (signr != SIGCHLD)
				continue;
			/* Check for SIGCHLD: it's special.  */
			while (sys_wait4(-1, NULL, WNOHANG, NULL) > 0)
				/* nothing */;
			continue;
		}

		if (ka->sa.sa_handler == SIG_DFL) {
			int exit_code = signr;

			/* Init gets no signals it doesn't want.  */
			if (current->pid == 1)
				continue;

			switch (signr) {
			case SIGCONT: case SIGCHLD: case SIGWINCH:
				continue;

			case SIGTSTP: case SIGTTIN: case SIGTTOU:
				if (is_orphaned_pgrp(current->pgrp))
					continue;
				/* FALLTHRU */

			case SIGSTOP:
				current->state = TASK_STOPPED;
				current->exit_code = signr;
				if (!(current->p_pptr->sig->action[SIGCHLD-1].sa.sa_flags & SA_NOCLDSTOP))
					notify_parent(current, SIGCHLD);
				schedule();
				continue;

			case SIGQUIT: case SIGILL: case SIGTRAP:
			case SIGABRT: case SIGFPE: case SIGSEGV:
				if (do_coredump(signr, regs))
					exit_code |= 0x80;
				/* FALLTHRU */

			default:
				sigaddset(&current->pending.signal, signr);
				recalc_sigpending(current);
				current->flags |= PF_SIGNALED;
				do_exit(exit_code);
				/* NOTREACHED */
			}
		}

		if (regs->regs[0])
			syscall_restart(regs, ka);
		/* Whee!  Actually deliver the signal.  */
		handle_signal(signr, ka, &info, oldset, regs);
		return 1;
	}

	/*
	 * Who's code doesn't conform to the restartable syscall convention
	 * dies here!!!  The li instruction, a single machine instruction,
	 * must directly be followed by the syscall instruction.
	 */
	if (regs->regs[0]) {
		if (regs->regs[2] == ERESTARTNOHAND ||
		    regs->regs[2] == ERESTARTSYS ||
		    regs->regs[2] == ERESTARTNOINTR) {
			regs->cp0_epc -= 8;
		}
	}
	return 0;
}
예제 #16
0
/* Note that 'init' is a special process: it doesn't get signals it doesn't
 * want to handle. Thus you cannot kill init even with a SIGKILL even by
 * mistake.
 */
static void do_signal(struct pt_regs *regs, unsigned long orig_i0)
{
	struct k_sigaction ka;
	int restart_syscall;
	sigset_t *oldset = sigmask_to_save();
	siginfo_t info;
	int signr;
	
	/* It's a lot of work and synchronization to add a new ptrace
	 * register for GDB to save and restore in order to get
	 * orig_i0 correct for syscall restarts when debugging.
	 *
	 * Although it should be the case that most of the global
	 * registers are volatile across a system call, glibc already
	 * depends upon that fact that we preserve them.  So we can't
	 * just use any global register to save away the orig_i0 value.
	 *
	 * In particular %g2, %g3, %g4, and %g5 are all assumed to be
	 * preserved across a system call trap by various pieces of
	 * code in glibc.
	 *
	 * %g7 is used as the "thread register".   %g6 is not used in
	 * any fixed manner.  %g6 is used as a scratch register and
	 * a compiler temporary, but it's value is never used across
	 * a system call.  Therefore %g6 is usable for orig_i0 storage.
	 */
	if (pt_regs_is_syscall(regs) &&
	    (regs->tstate & (TSTATE_XCARRY | TSTATE_ICARRY)))
		regs->u_regs[UREG_G6] = orig_i0;

#ifdef CONFIG_COMPAT
	if (test_thread_flag(TIF_32BIT)) {
		extern void do_signal32(sigset_t *, struct pt_regs *);
		do_signal32(oldset, regs);
		return;
	}
#endif	

	signr = get_signal_to_deliver(&info, &ka, regs, NULL);

	restart_syscall = 0;
	if (pt_regs_is_syscall(regs) &&
	    (regs->tstate & (TSTATE_XCARRY | TSTATE_ICARRY))) {
		restart_syscall = 1;
		orig_i0 = regs->u_regs[UREG_G6];
	}

	if (signr > 0) {
		if (restart_syscall)
			syscall_restart(orig_i0, regs, &ka.sa);
		handle_signal(signr, &ka, &info, oldset, regs);
		return;
	}
	if (restart_syscall &&
	    (regs->u_regs[UREG_I0] == ERESTARTNOHAND ||
	     regs->u_regs[UREG_I0] == ERESTARTSYS ||
	     regs->u_regs[UREG_I0] == ERESTARTNOINTR)) {
		/* replay the system call when we are done */
		regs->u_regs[UREG_I0] = orig_i0;
		regs->tpc -= 4;
		regs->tnpc -= 4;
		pt_regs_clear_syscall(regs);
	}
	if (restart_syscall &&
	    regs->u_regs[UREG_I0] == ERESTART_RESTARTBLOCK) {
		regs->u_regs[UREG_G1] = __NR_restart_syscall;
		regs->tpc -= 4;
		regs->tnpc -= 4;
		pt_regs_clear_syscall(regs);
	}

	/* If there's no signal to deliver, we just put the saved sigmask
	 * back
	 */
	restore_saved_sigmask();
}
예제 #17
0
/* Note that 'init' is a special process: it doesn't get signals it doesn't
 * want to handle. Thus you cannot kill init even with a SIGKILL even by
 * mistake.
 */
asmlinkage int do_signal(sigset_t *oldset, struct pt_regs * regs,
			 unsigned long orig_i0, int restart_syscall)
{
	unsigned long signr;
	siginfo_t info;
	struct k_sigaction *ka;
	
	if (!oldset)
		oldset = &current->blocked;

#ifdef CONFIG_SPARC32_COMPAT
	if (current->thread.flags & SPARC_FLAG_32BIT) {
		extern asmlinkage int do_signal32(sigset_t *, struct pt_regs *,
						  unsigned long, int);
		return do_signal32(oldset, regs, orig_i0, restart_syscall);
	}
#endif	
	for (;;) {
		spin_lock_irq(&current->sigmask_lock);
		signr = dequeue_signal(&current->blocked, &info);
		spin_unlock_irq(&current->sigmask_lock);
		
		if (!signr)
			break;

		if ((current->ptrace & PT_PTRACED) && signr != SIGKILL) {
			/* Do the syscall restart before we let the debugger
			 * look at the child registers.
			 */
			if (restart_syscall &&
			    (regs->u_regs[UREG_I0] == ERESTARTNOHAND ||
			     regs->u_regs[UREG_I0] == ERESTARTSYS ||
			     regs->u_regs[UREG_I0] == ERESTARTNOINTR)) {
				regs->u_regs[UREG_I0] = orig_i0;
				regs->tpc -= 4;
				regs->tnpc -= 4;
				restart_syscall = 0;
			}

			current->exit_code = signr;
			current->state = TASK_STOPPED;
			notify_parent(current, SIGCHLD);
			schedule();
			if (!(signr = current->exit_code))
				continue;
			current->exit_code = 0;
			if (signr == SIGSTOP)
				continue;

			/* Update the siginfo structure.  Is this good?  */
			if (signr != info.si_signo) {
				info.si_signo = signr;
				info.si_errno = 0;
				info.si_code = SI_USER;
				info.si_pid = current->p_pptr->pid;
				info.si_uid = current->p_pptr->uid;
			}

			/* If the (new) signal is now blocked, requeue it.  */
			if (sigismember(&current->blocked, signr)) {
				send_sig_info(signr, &info, current);
				continue;
			}
		}
		
		ka = &current->sig->action[signr-1];
		
		if (ka->sa.sa_handler == SIG_IGN) {
			if (signr != SIGCHLD)
				continue;

                        /* sys_wait4() grabs the master kernel lock, so
                         * we need not do so, that sucker should be
                         * threaded and would not be that difficult to
                         * do anyways.
                         */
                        while (sys_wait4(-1, NULL, WNOHANG, NULL) > 0)
                                ;
			continue;
		}
		if (ka->sa.sa_handler == SIG_DFL) {
			unsigned long exit_code = signr;
			
			if (current->pid == 1)
				continue;
			switch (signr) {
			case SIGCONT: case SIGCHLD: case SIGWINCH: case SIGURG:
				continue;

			case SIGTSTP: case SIGTTIN: case SIGTTOU:
				if (is_orphaned_pgrp(current->pgrp))
					continue;

			case SIGSTOP:
				if (current->ptrace & PT_PTRACED)
					continue;
				current->state = TASK_STOPPED;
				current->exit_code = signr;
				if (!(current->p_pptr->sig->action[SIGCHLD-1].sa.sa_flags &
				      SA_NOCLDSTOP))
					notify_parent(current, SIGCHLD);
				schedule();
				continue;

			case SIGQUIT: case SIGILL: case SIGTRAP:
			case SIGABRT: case SIGFPE: case SIGSEGV:
			case SIGBUS: case SIGSYS: case SIGXCPU: case SIGXFSZ:
				if (do_coredump(signr, regs))
					exit_code |= 0x80;
#ifdef DEBUG_SIGNALS
				/* Very useful to debug the dynamic linker */
				printk ("Sig %d going...\n", (int)signr);
				show_regs (regs);
#ifdef DEBUG_SIGNALS_TRACE
				{
					struct reg_window *rw = (struct reg_window *)(regs->u_regs[UREG_FP] + STACK_BIAS);
					unsigned long ins[8];
                                                
					while (rw &&
					       !(((unsigned long) rw) & 0x3)) {
					        copy_from_user(ins, &rw->ins[0], sizeof(ins));
						printk("Caller[%016lx](%016lx,%016lx,%016lx,%016lx,%016lx,%016lx)\n", ins[7], ins[0], ins[1], ins[2], ins[3], ins[4], ins[5]);
						rw = (struct reg_window *)(unsigned long)(ins[6] + STACK_BIAS);
					}
				}
#endif			
#ifdef DEBUG_SIGNALS_MAPS	
				printk("Maps:\n");
				read_maps();
#endif
#endif
				/* fall through */
			default:
				sig_exit(signr, exit_code, &info);
				/* NOT REACHED */
			}
		}
		if (restart_syscall)
			syscall_restart(orig_i0, regs, &ka->sa);
		handle_signal(signr, ka, &info, oldset, regs);
		return 1;
	}
	if (restart_syscall &&
	    (regs->u_regs[UREG_I0] == ERESTARTNOHAND ||
	     regs->u_regs[UREG_I0] == ERESTARTSYS ||
	     regs->u_regs[UREG_I0] == ERESTARTNOINTR)) {
		/* replay the system call when we are done */
		regs->u_regs[UREG_I0] = orig_i0;
		regs->tpc -= 4;
		regs->tnpc -= 4;
	}
	return 0;
}
예제 #18
0
/*
 * Note that 'init' is a special process: it doesn't get signals it doesn't
 * want to handle. Thus you cannot kill init even with a SIGKILL even by
 * mistake.
 *
 * Note that we go through the signals twice: once to check the signals that
 * the kernel can handle, and then we build all the user-level signal handling
 * stack-frames in one go after that.
 *
 * "r0" and "r19" are the registers we need to restore for system call
 * restart. "r0" is also used as an indicator whether we can restart at
 * all (if we get here from anything but a syscall return, it will be 0)
 */
asmlinkage int
do_signal(sigset_t *oldset, struct pt_regs * regs, struct switch_stack * sw,
          unsigned long r0, unsigned long r19)
{
    unsigned long single_stepping = ptrace_cancel_bpt(current);

    if (!oldset)
        oldset = &current->blocked;

    while (1) {
        unsigned long signr;
        struct k_sigaction *ka;
        siginfo_t info;

        spin_lock_irq(&current->sigmask_lock);
        signr = dequeue_signal(&current->blocked, &info);
        spin_unlock_irq(&current->sigmask_lock);

        if (!signr)
            break;

        if ((current->ptrace & PT_PTRACED) && signr != SIGKILL) {
            /* Let the debugger run.  */
            current->exit_code = signr;
            current->state = TASK_STOPPED;
            notify_parent(current, SIGCHLD);
            schedule();
            single_stepping |= ptrace_cancel_bpt(current);

            /* We're back.  Did the debugger cancel the sig?  */
            if (!(signr = current->exit_code))
                continue;
            current->exit_code = 0;

            /* The debugger continued.  Ignore SIGSTOP.  */
            if (signr == SIGSTOP)
                continue;

            /* Update the siginfo structure.  Is this good?  */
            if (signr != info.si_signo) {
                info.si_signo = signr;
                info.si_errno = 0;
                info.si_code = SI_USER;
                info.si_pid = current->p_pptr->pid;
                info.si_uid = current->p_pptr->uid;
            }

            /* If the (new) signal is now blocked, requeue it.  */
            if (sigismember(&current->blocked, signr)) {
                send_sig_info(signr, &info, current);
                continue;
            }
        }

        ka = &current->sig->action[signr-1];
        if (ka->sa.sa_handler == SIG_IGN) {
            if (signr != SIGCHLD)
                continue;
            /* Check for SIGCHLD: it's special.  */
            while (sys_wait4(-1, NULL, WNOHANG, NULL) > 0)
                /* nothing */;
            continue;
        }

        if (ka->sa.sa_handler == SIG_DFL) {
            int exit_code = signr & 0x7f;

            /* Init gets no signals it doesn't want.  */
            if (current->pid == 1)
                continue;

            switch (signr) {
            case SIGCONT:
            case SIGCHLD:
            case SIGWINCH:
                continue;

            case SIGTSTP:
            case SIGTTIN:
            case SIGTTOU:
                if (is_orphaned_pgrp(current->pgrp))
                    continue;
            /* FALLTHRU */

            case SIGSTOP:
                current->state = TASK_STOPPED;
                current->exit_code = signr;
                if (!(current->p_pptr->sig->action[SIGCHLD-1]
                        .sa.sa_flags & SA_NOCLDSTOP))
                    notify_parent(current, SIGCHLD);
                schedule();
                single_stepping |= ptrace_cancel_bpt(current);
                continue;

            case SIGQUIT:
            case SIGILL:
            case SIGTRAP:
            case SIGABRT:
            case SIGFPE:
            case SIGSEGV:
            case SIGBUS:
            case SIGSYS:
            case SIGXCPU:
            case SIGXFSZ:
                if (do_coredump(signr, regs))
                    exit_code |= 0x80;
            /* FALLTHRU */

            default:
                lock_kernel();
                sigaddset(&current->pending.signal, signr);
                current->flags |= PF_SIGNALED;
                do_exit(exit_code);
                /* NOTREACHED */
            }
            continue;
        }

        /* Whee!  Actually deliver the signal.  */
        if (r0) syscall_restart(r0, r19, regs, ka);
        handle_signal(signr, ka, &info, oldset, regs, sw);
        if (single_stepping)
            ptrace_set_bpt(current); /* re-set bpt */
        return 1;
    }

    if (r0 &&
            (regs->r0 == ERESTARTNOHAND ||
             regs->r0 == ERESTARTSYS ||
             regs->r0 == ERESTARTNOINTR)) {
        regs->r0 = r0;	/* reset v0 and a3 and replay syscall */
        regs->r19 = r19;
        regs->pc -= 4;
    }
    if (single_stepping)
        ptrace_set_bpt(current);	/* re-set breakpoint */

    return 0;
}