panic: Assertion in_epoch(net_epoch_preempt) failed at /syzkaller/managers/main/kernel/sys/netinet/igmp.c:LINE

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: 6bf933c4 Revert changes to rip6_bind() from r353292. This..
git tree: freebsd
console output: https://syzkaller.appspot.com/x/log.txt?x=10e281b3600000
dashboard link: https://syzkaller.appspot.com/bug?extid=3ae9b2cadb0cdeb247e1

Unfortunately, I don't have any reproducer for this crash yet.

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+3ae9b2...@syzkaller.appspotmail.com

login: panic: Assertion in_epoch(net_epoch_preempt) failed at
/syzkaller/managers/main/kernel/sys/netinet/igmp.c:3304
cpuid = 1
time = 1570621872
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


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.