----- "Joe Porter" <joe.porter(a)ccur.com&gt; wrote: Hi Joe, Sorry -- I didn't make myself clear enough in my question. What I meant was: did the original code in the crash x86_init() fall into the "if" clause here: if (!VALID_STRUCT(user_regs_struct)) { /* Use this hardwired version -- sometimes the * debuginfo doesn't pick this up even though * it exists in the kernel; it shouldn't change. */ Since the offset values and structure size required shouldn't have changed (even though the names did), I'm presuming that x86_init() did *not* fall into that code, because if it did, the offsets and size values would have been assigned, and you wouldn't have seen the ultimate error. So my guess is that the user_regs_struct *is* in the debuginfo of the new kernel. That's what I'm trying to confirm here. In other words, if you do this: # gdb vmlinux ... (gdb) ptype struct user_regs_struct does it know about the structure? If it does, then all the changes you made in the "if" part of the patch are not required. The x86_64 would use x86_64_init() instead of x86_init(), so it's irrelevant. And the x86_64 code doesn't care about those fields. I appreciate your time -- sorry to drag you down into my world. (Please forgive an old "ccur.com" guy...) Thanks, Dave