Device Mapper version 4.16.0 loaded Fatal user address access from kernel mode from dm_uninit_msg at ffffffff80657ec5 Fatal trap 12: page fault while in kernel mode fault virtual address = 0x2e2e7a4a7054 fault code = supervisor read data, page not present instruction pointer = 0x8:0xffffffff80657ec5 current process = 987 kernel: type 12 trap, code=0 Stopped at _kfree+0x45: movl 0x54(%rax),%r13d db>