Merge tag 'ktest-v4.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-ktest

Pull ktest fixes from Steven Rostedt:
"Greg Kroah-Hartman reported to me that the ktest of v4.11-rc1 locked
up in an infinite loop while doing the make mrproper.

Looking into the cause I noticed that a recent update to the function
run_command (used for running all shell commands, including "make
mrproper") changed the internal loop to use the function
wait_for_input.

The wait_for_input function uses select to look at two file
descriptors. One is the file descriptor of the command it is running,
the other is STDIN. The STDIN check was not checking the return status
of the sysread call, and was also just writing a lot of data into
syswrite without regard to the size of the data read.

Changing the code to check the return status of sysread, and also to
still process the passed in descriptor data without looping back to
the select fixed Greg's problem.

While looking at this code I also realized that the loop did not honor
the timeout if STDIN always had input (or for some reason return
error). this could prevent wait_for_input to timeout on the file
descriptor it is suppose to be waiting for. That is fixed too"

* tag 'ktest-v4.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-ktest:
ktest: Make sure wait_for_input does honor the timeout
ktest: Fix while loop in wait_for_input

tools/testing/ktest/ktest.pl

···
 sub wait_for_input
 {
     my ($fp, $time) = @_;
+    my $start_time;
     my $rin;
     my $rout;
     my $nr;
···
     vec($rin, fileno($fp), 1) = 1;
     vec($rin, fileno(\*STDIN), 1) = 1;
 
+    $start_time = time;
+
     while (1) {
 	$nr = select($rout=$rin, undef, undef, $time);
 
-	if ($nr <= 0) {
-	    return undef;
-	}
+	last if ($nr <= 0);
 
 	# copy data from stdin to the console
 	if (vec($rout, fileno(\*STDIN), 1) == 1) {
-	    sysread(\*STDIN, $buf, 1000);
-	    syswrite($fp, $buf, 1000);
+	    $nr = sysread(\*STDIN, $buf, 1000);
+	    syswrite($fp, $buf, $nr) if ($nr > 0);
+	}
+
+	# The timeout is based on time waiting for the fp data
+	if (vec($rout, fileno($fp), 1) != 1) {
+	    last if (defined($time) && (time - $start_time > $time));
 	    next;
 	}
 
···
 	    last if ($ch eq "\n");
 	}
 
-	if (!length($line)) {
-	    return undef;
-	}
+	last if (!length($line));
 
 	return $line;
     }
+    return undef;
 }
 
 sub reboot_to {