Comment 1 for bug 1978082

Comment copied from Colin's comment in the upstream stress-ng project [1]:

This appears to be a kernel issue triggered by the stress-ng dev stressor on a tty device. One can corner this by working through the devices by specifying the dev file, for example: stress-ng --dev 0 --dev-file /dev/tty0

By the look of the commit it could be due to the enablement of the TIOCGETD ioctl() call, the commit has the following change:

 /*
  * On some older 3.13 kernels this can lock up, need to add
  * a method to detect and skip this somehow. For the moment
  * disable this stress test.
  */
-#if defined(TIOCGETD) && 0
+#if defined(TIOCGETD)
        {
        {
                int ldis;

@@ -705,9 +779,13 @@ static void stress_dev_tty(
                if (ret == 0) {
                        ret = ioctl(fd, TIOCSETD, &ldis);
                }
+#else
+ UNEXPECTED
 #endif

This seems to match up with the ldisc issue shown in the kernel trace. So I suspect there is a kernel fix for this that needs to be backported as this does not occur with newer kernels.

[1] https://github.com/ColinIanKing/stress-ng/issues/202