kernel panic at kern/arch/x86/trap.c:540, from core 3: Double fault!  Check the kernel stack pointer; you likely ran off the end of the stack.
HW TRAP frame at 0xfffffff00001af40 on core 3
  rax  0x000000000000003d
  rbx  0xffffffffc8668140
  rcx  0xffffffffc8668148
  rdx  0x00000020e39d48a1
  rbp  0xfffffff0000a6fd8
  rsi  0x0000000000000003
  rdi  0xffffffffc8668140
  r8   0x0000000000000000
  r9   0xffffffffc8668238
  r10  0x0000000000000078
  r11  0xffffffffc86681f8
  r12  0xffff80000217cf60
  r13  0x0000000000000003
  r14  0x0000000000000000
  r15  0x0000000000000003
  trap 0x00000008 Double Fault
  gsbs 0xffffffffc8668140
  fsbs 0x0000000000000000
  err  0x--------00000000
  rip  0xffffffffc209f6c1
  cs   0x------------0008
  flag 0x0000000000010246
  rsp  0xfffffff0000a6fd8
  ss   0x------------0010
Backtrace of kernel context on Core 3:
#01 [<0xffffffffc209f6c1>] in cpu_halt at arch/x86/idle.c:20
#02 [<0xffffffffc2054706>] in __smp_idle at src/smp.c:84