Beispiel #1
0
asmlinkage void do_rt_sigreturn(struct pt_regs *regs)
{
	struct rt_signal_frame __user *sf;
	unsigned int psr, pc, npc;
	__siginfo_fpu_t __user *fpu_save;
	__siginfo_rwin_t __user *rwin_save;
	sigset_t set;
	int err;

	synchronize_user_stack();
	sf = (struct rt_signal_frame __user *) regs->u_regs[UREG_FP];
	if (!access_ok(VERIFY_READ, sf, sizeof(*sf)) ||
	    (((unsigned long) sf) & 0x03))
		goto segv;

	err = __get_user(pc, &sf->regs.pc);
	err |= __get_user(npc, &sf->regs.npc);
	err |= ((pc | npc) & 0x03);

	err |= __get_user(regs->y, &sf->regs.y);
	err |= __get_user(psr, &sf->regs.psr);

	err |= __copy_from_user(&regs->u_regs[UREG_G1],
				&sf->regs.u_regs[UREG_G1], 15 * sizeof(u32));

	regs->psr = (regs->psr & ~PSR_ICC) | (psr & PSR_ICC);

	/* Prevent syscall restart.  */
	pt_regs_clear_syscall(regs);

	err |= __get_user(fpu_save, &sf->fpu_save);
	if (!err && fpu_save)
		err |= restore_fpu_state(regs, fpu_save);
	err |= __copy_from_user(&set, &sf->mask, sizeof(sigset_t));
	err |= restore_altstack(&sf->stack);
	
	if (err)
		goto segv;
		
	regs->pc = pc;
	regs->npc = npc;
	
	err |= __get_user(rwin_save, &sf->rwin_save);
	if (!err && rwin_save) {
		if (restore_rwin_state(rwin_save))
			goto segv;
	}

	set_current_blocked(&set);
	return;
segv:
	force_sig(SIGSEGV, current);
}
Beispiel #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.
 */
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();
}
Beispiel #3
0
void do_rt_sigreturn(struct pt_regs *regs)
{
	struct rt_signal_frame __user *sf;
	unsigned long tpc, tnpc, tstate;
	__siginfo_fpu_t __user *fpu_save;
	__siginfo_rwin_t __user *rwin_save;
	sigset_t set;
	int err;

	/* Always make any pending restarted system calls return -EINTR */
	current_thread_info()->restart_block.fn = do_no_restart_syscall;

	synchronize_user_stack ();
	sf = (struct rt_signal_frame __user *)
		(regs->u_regs [UREG_FP] + STACK_BIAS);

	/* 1. Make sure we are not getting garbage from the user */
	if (((unsigned long) sf) & 3)
		goto segv;

	err = get_user(tpc, &sf->regs.tpc);
	err |= __get_user(tnpc, &sf->regs.tnpc);
	if (test_thread_flag(TIF_32BIT)) {
		tpc &= 0xffffffff;
		tnpc &= 0xffffffff;
	}
	err |= ((tpc | tnpc) & 3);

	/* 2. Restore the state */
	err |= __get_user(regs->y, &sf->regs.y);
	err |= __get_user(tstate, &sf->regs.tstate);
	err |= copy_from_user(regs->u_regs, sf->regs.u_regs, sizeof(regs->u_regs));

	/* User can only change condition codes and %asi in %tstate. */
	regs->tstate &= ~(TSTATE_ASI | TSTATE_ICC | TSTATE_XCC);
	regs->tstate |= (tstate & (TSTATE_ASI | TSTATE_ICC | TSTATE_XCC));

	err |= __get_user(fpu_save, &sf->fpu_save);
	if (!err && fpu_save)
		err |= restore_fpu_state(regs, fpu_save);

	err |= __copy_from_user(&set, &sf->mask, sizeof(sigset_t));
	if (err || do_sigaltstack(&sf->stack, NULL, (unsigned long)sf) == -EFAULT)
		goto segv;

	err |= __get_user(rwin_save, &sf->rwin_save);
	if (!err && rwin_save) {
		if (restore_rwin_state(rwin_save))
			goto segv;
	}

	regs->tpc = tpc;
	regs->tnpc = tnpc;

	/* Prevent syscall restart.  */
	pt_regs_clear_syscall(regs);

	set_current_blocked(&set);
	return;
segv:
	force_sig(SIGSEGV, current);
}
Beispiel #4
0
asmlinkage void do_sigreturn(struct pt_regs *regs)
{
	struct signal_frame __user *sf;
	unsigned long up_psr, pc, npc;
	sigset_t set;
	__siginfo_fpu_t __user *fpu_save;
	__siginfo_rwin_t __user *rwin_save;
	int err;

	/* Always make any pending restarted system calls return -EINTR */
	current_thread_info()->restart_block.fn = do_no_restart_syscall;

	synchronize_user_stack();

	sf = (struct signal_frame __user *) regs->u_regs[UREG_FP];

	/* 1. Make sure we are not getting garbage from the user */
	if (!access_ok(VERIFY_READ, sf, sizeof(*sf)))
		goto segv_and_exit;

	if (((unsigned long) sf) & 3)
		goto segv_and_exit;

	err = __get_user(pc,  &sf->info.si_regs.pc);
	err |= __get_user(npc, &sf->info.si_regs.npc);

	if ((pc | npc) & 3)
		goto segv_and_exit;

	/* 2. Restore the state */
	up_psr = regs->psr;
	err |= __copy_from_user(regs, &sf->info.si_regs, sizeof(struct pt_regs));

	/* User can only change condition codes and FPU enabling in %psr. */
	regs->psr = (up_psr & ~(PSR_ICC | PSR_EF))
		  | (regs->psr & (PSR_ICC | PSR_EF));

	/* Prevent syscall restart.  */
	pt_regs_clear_syscall(regs);

	err |= __get_user(fpu_save, &sf->fpu_save);
	if (fpu_save)
		err |= restore_fpu_state(regs, fpu_save);
	err |= __get_user(rwin_save, &sf->rwin_save);
	if (rwin_save)
		err |= restore_rwin_state(rwin_save);

	/* This is pretty much atomic, no amount locking would prevent
	 * the races which exist anyways.
	 */
	err |= __get_user(set.sig[0], &sf->info.si_mask);
	err |= __copy_from_user(&set.sig[1], &sf->extramask,
			        (_NSIG_WORDS-1) * sizeof(unsigned int));
			   
	if (err)
		goto segv_and_exit;

	sigdelsetmask(&set, ~_BLOCKABLE);
	spin_lock_irq(&current->sighand->siglock);
	current->blocked = set;
	recalc_sigpending();
	spin_unlock_irq(&current->sighand->siglock);
	return;

segv_and_exit:
	force_sig(SIGSEGV, current);
}
Beispiel #5
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);
	}
}
Beispiel #6
0
asmlinkage void do_rt_sigreturn(struct pt_regs *regs)
{
	struct rt_signal_frame __user *sf;
	unsigned int psr, pc, npc;
	__siginfo_fpu_t __user *fpu_save;
	__siginfo_rwin_t __user *rwin_save;
	mm_segment_t old_fs;
	sigset_t set;
	stack_t st;
	int err;

	synchronize_user_stack();
	sf = (struct rt_signal_frame __user *) regs->u_regs[UREG_FP];
	if (!access_ok(VERIFY_READ, sf, sizeof(*sf)) ||
	    (((unsigned long) sf) & 0x03))
		goto segv;

	err = __get_user(pc, &sf->regs.pc);
	err |= __get_user(npc, &sf->regs.npc);
	err |= ((pc | npc) & 0x03);

	err |= __get_user(regs->y, &sf->regs.y);
	err |= __get_user(psr, &sf->regs.psr);

	err |= __copy_from_user(&regs->u_regs[UREG_G1],
				&sf->regs.u_regs[UREG_G1], 15 * sizeof(u32));

	regs->psr = (regs->psr & ~PSR_ICC) | (psr & PSR_ICC);

	/* Prevent syscall restart.  */
	pt_regs_clear_syscall(regs);

	err |= __get_user(fpu_save, &sf->fpu_save);
	if (!err && fpu_save)
		err |= restore_fpu_state(regs, fpu_save);
	err |= __copy_from_user(&set, &sf->mask, sizeof(sigset_t));
	
	err |= __copy_from_user(&st, &sf->stack, sizeof(stack_t));
	
	if (err)
		goto segv;
		
	regs->pc = pc;
	regs->npc = npc;
	
	/* It is more difficult to avoid calling this function than to
	 * call it and ignore errors.
	 */
	old_fs = get_fs();
	set_fs(KERNEL_DS);
	do_sigaltstack((const stack_t __user *) &st, NULL, (unsigned long)sf);
	set_fs(old_fs);

	err |= __get_user(rwin_save, &sf->rwin_save);
	if (!err && rwin_save) {
		if (restore_rwin_state(rwin_save))
			goto segv;
	}

	sigdelsetmask(&set, ~_BLOCKABLE);
	spin_lock_irq(&current->sighand->siglock);
	current->blocked = set;
	recalc_sigpending();
	spin_unlock_irq(&current->sighand->siglock);
	return;
segv:
	force_sig(SIGSEGV, current);
}
/* 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);
	}
}
Beispiel #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.
 */
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();
	}
}
Beispiel #9
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 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();
	}
}
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);
	}
}
void do_rt_sigreturn(struct pt_regs *regs)
{
	struct rt_signal_frame __user *sf;
	unsigned long tpc, tnpc, tstate;
	__siginfo_fpu_t __user *fpu_save;
	__siginfo_rwin_t __user *rwin_save;
	sigset_t set;
	int err;

	
	current_thread_info()->restart_block.fn = do_no_restart_syscall;

	synchronize_user_stack ();
	sf = (struct rt_signal_frame __user *)
		(regs->u_regs [UREG_FP] + STACK_BIAS);

	
	if (((unsigned long) sf) & 3)
		goto segv;

	err = get_user(tpc, &sf->regs.tpc);
	err |= __get_user(tnpc, &sf->regs.tnpc);
	if (test_thread_flag(TIF_32BIT)) {
		tpc &= 0xffffffff;
		tnpc &= 0xffffffff;
	}
	err |= ((tpc | tnpc) & 3);

	
	err |= __get_user(regs->y, &sf->regs.y);
	err |= __get_user(tstate, &sf->regs.tstate);
	err |= copy_from_user(regs->u_regs, sf->regs.u_regs, sizeof(regs->u_regs));

	
	regs->tstate &= ~(TSTATE_ASI | TSTATE_ICC | TSTATE_XCC);
	regs->tstate |= (tstate & (TSTATE_ASI | TSTATE_ICC | TSTATE_XCC));

	err |= __get_user(fpu_save, &sf->fpu_save);
	if (!err && fpu_save)
		err |= restore_fpu_state(regs, fpu_save);

	err |= __copy_from_user(&set, &sf->mask, sizeof(sigset_t));
	err |= do_sigaltstack(&sf->stack, NULL, (unsigned long)sf);

	if (err)
		goto segv;

	err |= __get_user(rwin_save, &sf->rwin_save);
	if (!err && rwin_save) {
		if (restore_rwin_state(rwin_save))
			goto segv;
	}

	regs->tpc = tpc;
	regs->tnpc = tnpc;

	
	pt_regs_clear_syscall(regs);

	sigdelsetmask(&set, ~_BLOCKABLE);
	set_current_blocked(&set);
	return;
segv:
	force_sig(SIGSEGV, current);
}