There&#x27;s apparently an even worse usermode-triggerable denial of service in the Pi related to breakpoints, one that allows usermode code to completely hang it: <a href="http:&#x2F;&#x2F;hackaday.com&#x2F;2015&#x2F;08&#x2F;25&#x2F;raspberry-pi-halt-and-catch-well-halt&#x2F;" rel="nofollow">http:&#x2F;&#x2F;hackaday.com&#x2F;2015&#x2F;08&#x2F;25&#x2F;raspberry-pi-halt-and-catch-w...</a>