frv: restart_block.fn needs to be reset on sigreturn

Reset restart_block.fn on executing a sigreturn such that any currently
pending system call restarts will be forced to return -EINTR.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

arch/frv/kernel/signal.c

@@ -121,6 +121,9 @@ static int restore_sigcontext(struct sigcontext __user *sc, int *_gr8)
 	struct user_context *user = current->thread.user;
 	unsigned long tbr, psr;
 
+	/* Always make any pending restarted system calls return -EINTR */
+	current_thread_info()->restart_block.fn = do_no_restart_syscall;
+
 	tbr = user->i.tbr;
 	psr = user->i.psr;
 	if (copy_from_user(user, &sc->sc_context, sizeof(sc->sc_context)))