ghe_read: file: 0000010039860c80 buf: 0000007fbfffb7f0 sz: 128 *ppos: 0 No data to read, waiting ... ghe_open: inode: 72997, file: 0000010039860380 ghe_write: file: 0000010039860380 buf: 0000007fbfffc820 sz: 1 *ppos: 0 Wakeup read user ... Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000 printing rip: ffffffff8012199b PML4 39435067 PGD 3961d067 PMD 0 Oops: 0000 CPU 0 Pid: 1583, comm: devwrite Not tainted RIP: 0010:[]{__wake_up+91} RSP: 0018:0000010039653ed8 EFLAGS: 00010046 RAX: 0000000000000000 RBX: 000001003cb71580 RCX: 0000010039652000 RDX: 0000000000000000 RSI: 0000000000000073 RDI: 0000000000000000 RBP: 0000010039653f18 R08: ffffffffffffffff R09: 0000000000000001 R10: ffffffff805f2040 R11: 0000000000000000 R12: 0000000000000001 R13: 000001003cb71500 R14: 000001003cb71588 R15: 000001003cb71580 FS: 0000002a958c94c0(0000) GS:ffffffff805eb3c0(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b CR2: 0000000000000000 CR3: 0000000000101000 CR4: 00000000000006e0 Call Trace: []{__wake_up+111} []{:ghe:ghe_write+244} []{sys_write+178} []{system_call+119} Process devwrite (pid: 1583, stackpage=10039653000) Stack: 0000010039653ed8 0000000000000018 ffffffff801219af 0000000000000002 00000001805f2088 0000000000000202 0000000000000001 0000000000000001 00000100398603b8 0000007fbfffc820 0000000000000000 0000000000000001 ffffffffa01023f4 0000000000000001 0000010039860380 ffffffffffffffea 0000007fbfffc820 0000000000000000 ffffffff80161b52 0000000000000000 0000002a9566b020 0000007fbfffcc40 0000000000400670 0000000000000000 ffffffff801102f7 0000000000000246 0000002a9568baa0 0000000000000000 fefefefefefefeff 0000000000000001 0000000000000031 0000000000000001 0000007fbfffc820 0000000000000003 0000000000000001 0000002a957501d2 0000000000000033 0000000000010202 0000007fbfffc808 000000000000002b Call Trace: []{__wake_up+111} []{:ghe:ghe_write+244} []{sys_write+178} []{system_call+119} Code: 48 8b 07 85 45 cc 74 1b 8b 75 cc 31 c9 31 d2 e8 71 e1 ff ff Kernel panic: Fatal exception