kernel warning at kern/src/event.c:374, from core 1: [kernel] Null ev_q - kernel code should check before sending!
Stack Backtrace on Core 1:
#01 [<0xffffffffc200a38c>] in backtrace at src/kdebug.c:229
#02 [<0xffffffffc2009bb4>] in _warn at src/init.c:322
#03 [<0xffffffffc2007732>] in send_event at src/event.c:374
#04 [<0xffffffffc2056b45>] in sys_send_event at src/syscall.c:1439
#05 [<0xffffffffc205a319>] in syscall at src/syscall.c:2496
#06 [<0xffffffffc205a4f8>] in run_local_syscall at src/syscall.c:2531
#07 [<0xffffffffc205aa39>] in prep_syscalls at src/syscall.c:2551
#08 [<0xffffffffc20ac1e2>] in sysenter_callwrapper at arch/x86/trap.c:854
kernel panic at kern/arch/x86/trap.c:312, from core 3: Proc-ful Page Fault in the Kernel at 0x00007f8006402bc0!
HW TRAP frame at 0xfffffff0000d0cc0 on core 3
  rax  0x00007f7fffa01200
  rbx  0x0000000006a00d40
  rcx  0xffff800005ee7708
  rdx  0xfffffff0000d0df0
  rbp  0xfffffff0000d0d88
  rsi  0x00007f8006402bc0
  rdi  0xffff800002175f00
  r8   0x0000000000000000
  r9   0x0000000000000000
  r10  0x000010000000a4c0
  r11  0x0000000000000202
  r12  0xffff800002175f00
  r13  0xffff800002175f00
  r14  0xfffffff0000d0df0
  r15  0x0000000000000000
  trap 0x0000000e Page Fault
  gsbs 0xffffffffc8996340
  fsbs 0x0000000000000000
  err  0x--------00000000
  rip  0xffffffffc2007019
  cs   0x------------0008
  flag 0x0000000000010286
  rsp  0xfffffff0000d0d88
  ss   0x------------0010
Backtrace of kernel context on Core 3:
#01 [<0xffffffffc2007019>] in post_ev_msg.isra.1 at src/event.c:82
#02 [<     [inline]     >] in post_vc_msg at src/event.c:106
#02 [<0xffffffffc20078a6>] in post_vcore_event at src/event.c:489
#03 [<0xffffffffc2057822>] in sys_self_notify at src/syscall.c:1425
#04 [<0xffffffffc205a319>] in syscall at src/syscall.c:2496
#05 [<0xffffffffc205a4f8>] in run_local_syscall at src/syscall.c:2531
#06 [<0xffffffffc205aa39>] in prep_syscalls at src/syscall.c:2551
#07 [<0xffffffffc20ac1e2>] in sysenter_callwrapper at arch/x86/trap.c:854
[kernel] Unknown mbox type 0!