http://bugs.winehq.org/show_bug.cgi?id=58755
--- Comment #13 from Alexandre Julliard julliard@winehq.org --- (In reply to Zeb Figura from comment #8)
I actually ended up partially debugging this. The problem is that Wine sometimes does WCB16_REGS calls with a zeroed context, so it sets zero %fs and %gs. Some CPUs crash when %gs is zero even in 64-bit mode, mine included.
Thank you for looking into this!