Re: [PATCH v15 13/25] x86/reboot: Add ljmp instructions to stacktool whitelist

From: H. Peter Anvin
Date: Wed Jan 20 2016 - 00:52:36 EST


On 01/19/16 21:42, Josh Poimboeuf wrote:
>>>>
>>>> Apparently(?) xen treats the ud2 special when it's followed by "78 65
>>>> 6e". This is confusing for stacktool because ud2 is normally a dead
>>>> end, and it thinks the instructions after it will never run.
>>>>

Cute. UD2 followed by three ASCII characters. I guess that becomes
really fun when using UD2 + a string for error reporting. Of course, no
software does that...

-hpa