Initialize FPU sooner. Prompted by: cperciva@

[cperciva]

This patch works fine, but when I try to use the FPU from an SI_SUB_CPU sysinit (after calling fpu_kern_enter) I get:

kernel trap 22 with interrupts disabled
kernel trap 6 with interrupts disabled


Fatal trap 6: arithmetic trap while in kernel mode
cpuid = 0; apic id = 00
instruction pointer	= 0x20:0xffffffff8105fa8b
stack pointer	        = 0x28:0xffffffff8227ba90
frame pointer	        = 0x28:0xffffffff8227bb20
code segment		= base 0x0, limit 0xfffff, type 0x1b
			= DPL 0, pres 1, long 1, def32 0, gran 1
processor eflags	= resume, IOPL = 0
current process		= 0 ()
[ thread pid 0 tid 0 ]
Stopped at      init_TSC+0x3cb: fstpl   -0x68(%rbp)
db>

This is a different error from before, but maybe there's something else trap-related which needs to be done before the FPU becomes usable?

[cem]

Insufficiently motivated to follow this up :-).