Bug 241131 - Panic: Assertion in_epoch(net_epoch_preempt) failed
Summary: Panic: Assertion in_epoch(net_epoch_preempt) failed
Status: Closed FIXED
Alias: None
Product: Base System
Classification: Unclassified
Component: kern (show other bugs)
Version: CURRENT
Hardware: Any Any
: --- Affects Only Me
Assignee: freebsd-bugs (Nobody)
URL:
Keywords: crash
Depends on:
Blocks:
 
Reported: 2019-10-08 13:24 UTC by rz-rpi03
Modified: 2022-10-12 00:50 UTC (History)
2 users (show)

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Description rz-rpi03 2019-10-08 13:24:16 UTC 
After upgrading from r352935 to base r353304 the kernel panics after a few minutes.

# panic: Assertion in_epoch(net_epoch_prempt) failed at /usr/src/sys/netinet/igmp.c:3304
cpuid = 0
time = 1570538447
KDB: stack backtrace:
db_trace_self() at db_trace_self_wrapper+0x28
...
db_trace_self_wrapper() at vpanic+0x18c
...
vpanic at panic+0x44
...
panic() at igmp_fasttimo+0xadc
...
igmp_fasttimo() at pffasttimo+0x30
...
pffasttimo() at softclock_call_cc+0x110
...
softclock_call_cc() at softclock+0x84
...
softclock() at ithread_loop+0x1f4
...
ithread_loop() at fork_exit+0x7c
...
fork_exit() at fork_trampoline+0x10
...
KDB: enter: Panic
[ thread pid 12 tid 100016 ]
Stopped at      0
db> 

Regards, Ralf
Comment 1 Mark Johnston freebsd_committer freebsd_triage 2019-10-09 13:38:03 UTC 
This was reported by syzbot as well:
https://syzkaller.appspot.com/bug?id=62c827605a6895d89eece9e97319add39d87153b
Comment 2 rz-rpi03 2019-10-13 09:21:38 UTC 
The EPOCH related fixes in the network stack over the last days let the panic
disappear. In other words: No panic happend in more than 24 hours uptime.
Thank you all.