panic: Assertion in_epoch(net_epoch_preempt) failed at /syzkaller/managers/main/kernel/sys/net/if.c:3827 cpuid = 0 time = 1570607230 KDB: stack backtrace: db_trace_self_wrapper() at db_trace_self_wrapper+0x47/frame 0xfffffe00242f45b0 vpanic() at vpanic+0x1e0/frame 0xfffffe00242f4610 panic() at panic+0x43/frame 0xfffffe00242f4670 if_setlladdr() at if_setlladdr+0x34c/frame 0xfffffe00242f46e0 ifhwioctl() at ifhwioctl+0x9e0/frame 0xfffffe00242f4770 ifioctl() at ifioctl+0x4c2/frame 0xfffffe00242f4840 kern_ioctl() at kern_ioctl+0x465/frame 0xfffffe00242f48b0 sys_ioctl() at sys_ioctl+0x267/frame 0xfffffe00242f4980 amd64_syscall() at amd64_syscall+0x477/frame 0xfffffe00242f4ab0 fast_syscall_common() at fast_syscall_common+0x101/frame 0xfffffe00242f4ab0 --- syscall (54, FreeBSD ELF64, sys_ioctl), rip = 0x8004882ca, rsp = 0x7fffffffe428, rbp = 0x7fffffffe470 --- KDB: enter: panic [ thread pid 761 tid 100114 ] Stopped at kdb_enter+0x6a: movq $0,kdb_why