dfrig_nat[go1]: BEFORE dispatch: ch=0xffffffff82601140 ch->dma=0 (NULL means DMA unavailable, ata-dma.c:153) atadev->unit=0
dfrig_nat[go1]: dispatching production ata_national_setmode(dev, ATA_PIO_MAX) (RUNNING KERNEL own copy)
Fatal user address access from kernel mode from sysctl at ffffffff803217e5


Fatal trap 12: page fault while in kernel mode
cpuid = 2; lapic id = 2
fault virtual address	= 0x58
fault code		= supervisor write data, page not present
instruction pointer	= 0x8:0xffffffff803217e5
stack pointer	        = 0x10:0xfffff8011823f6d8
frame pointer	        = 0x10:0xfffff8011823f728
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		= 1065
current thread          = pri 6 
kernel: type 12 trap, code=2

CPU2 stopping CPUs: 0x0000003b
 stopped
Stopped at      ata_national_setmode+0x65:      movl    $0x10,0x58(%rax)
db>