Fatal trap 9: general protection fault while in kernel mode
cpuid = 1; lapic id = 1
instruction pointer	= 0x8:0xffffffff8090717e
stack pointer	        = 0x10:0xfffff8011848d688
frame pointer	        = 0x10:0xfffff8011848d6c8
code segment		= base 0x0, limit 0xfffff, type 0x1b
			= DPL 0, pres 1, long 0, def32 0, gran 1
processor eflags	= interrupt enabled, resume, IOPL = 0
current process		= 1021
current thread          = pri 10 
kernel: type 9 trap, code=0

CPU1 stopping CPUs: 0x0000003d
 stopped
Stopped at      ffs_update+0x3e:        cmpb    $0,0xd2(%r13)
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