panic: Assertion in_epoch(net_epoch_preempt) failed at /syzkaller/managers/main/kernel/sys/netinet/igmp.c:3304
cpuid = 0
time = 1570653228
KDB: stack backtrace:
db_trace_self_wrapper() at db_trace_self_wrapper+0x47/frame 0xfffffe001a1596d0
vpanic() at vpanic+0x1e0/frame 0xfffffe001a159730
panic() at panic+0x43/frame 0xfffffe001a159790
igmp_fasttimo() at igmp_fasttimo+0x12f4/frame 0xfffffe001a159890
pffasttimo() at pffasttimo+0x6a/frame 0xfffffe001a1598d0
softclock_call_cc() at softclock_call_cc+0x216/frame 0xfffffe001a1599b0
softclock() at softclock+0xa3/frame 0xfffffe001a1599f0
ithread_loop() at ithread_loop+0x2f2/frame 0xfffffe001a159a60
fork_exit() at fork_exit+0xb0/frame 0xfffffe001a159ab0
fork_trampoline() at fork_trampoline+0xe/frame 0xfffffe001a159ab0
--- trap 0, rip = 0, rsp = 0, rbp = 0 ---
KDB: enter: panic
[ thread pid 12 tid 100018 ]
Stopped at kdb_enter+0x6a: movq $0,kdb_why