Fatal trap 12: page fault while in kernel mode cpuid = 1; apic id = 01 fault virtual address = 0x418 fault code = supervisor read data, page not present instruction pointer = 0x20:0xffffffff81042ad8 stack pointer = 0x28:0xfffffe0020f1c5f0 frame pointer = 0x28:0xfffffe0020f1c6a0 code segment = base 0x0, limit 0xfffff, type 0x1b = DPL 0, pres 1, long 1, def32 0, gran 1 processor eflags = interrupt enabled, resume, IOPL = 0 current process = 12691 (syz-executor.3) trap number = 12 panic: page fault cpuid = 1 time = 1559701749 KDB: stack backtrace: db_trace_self_wrapper() at db_trace_self_wrapper+0x47/frame 0xfffffe0020f1c250 vpanic() at vpanic+0x1e0/frame 0xfffffe0020f1c2b0 panic() at panic+0x43/frame 0xfffffe0020f1c310 trap_fatal() at trap_fatal+0x4c6/frame 0xfffffe0020f1c390 trap_pfault() at trap_pfault+0x9f/frame 0xfffffe0020f1c400 trap() at trap+0x44d/frame 0xfffffe0020f1c520 calltrap() at calltrap+0x8/frame 0xfffffe0020f1c520 --- trap 0xc, rip = 0xffffffff81042ad8, rsp = 0xfffffe0020f1c5f0, rbp = 0xfffffe0020f1c6a0 --- _sx_xlock_hard() at _sx_xlock_hard+0x2f8/frame 0xfffffe0020f1c6a0 _sx_xlock() at _sx_xlock+0x136/frame 0xfffffe0020f1c6f0 sosend_generic() at sosend_generic+0x1a0/frame 0xfffffe0020f1c7c0 sosend() at sosend+0xc6/frame 0xfffffe0020f1c830 soo_write() at soo_write+0x61/frame 0xfffffe0020f1c870 dofilewrite() at dofilewrite+0xfd/frame 0xfffffe0020f1c8d0 kern_writev() at kern_writev+0x66/frame 0xfffffe0020f1c910 sys_write() at sys_write+0xd2/frame 0xfffffe0020f1c980 amd64_syscall() at amd64_syscall+0x436/frame 0xfffffe0020f1cab0 fast_syscall_common() at fast_syscall_common+0x101/frame 0xfffffe0020f1cab0 --- syscall (198, FreeBSD ELF64, nosys), rip = 0x4131ba, rsp = 0x7fffdfffdf38, rbp = 0x3 --- KDB: enter: panic [ thread pid 12691 tid 100816 ] Stopped at kdb_enter+0x6a: movq $0,kdb_why