Bug 254073 - current suddenly panics - due to machine on network with clock one year in the future?
Summary: current suddenly panics - due to machine on network with clock one year in th...
Status: New
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:
Depends on:
Blocks:
 
Reported: 2021-03-06 18:54 UTC by Martin Birgmeier
Modified: 2021-03-06 18:54 UTC (History)
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Description Martin Birgmeier 2021-03-06 18:54:16 UTC 
Scenario:
- FreeBSD current running as a VM under Hyper-V
- current as of Feb 14

FreeBSD 14.0-CURRENT #0 MBi/main-n243568-f90684b8744: Sun Feb 14 15:24:21 CET 2021
    root@v903.xyzzy:/net/hal/z/OBJ/FreeBSD/amd64/src/MBi/main/amd64.amd64/sys/XYZZY_SMP_NOSPIN_HYPERV
FreeBSD clang version 11.0.1 (git@github.com:llvm/llvm-project.git llvmorg-11.0.1-0-g43ff75f2c3fe)

- (the local changes in the MBi/main branch are harmless)
- this VM has been running fine for hours and has never crashed before

- Another (physical) machine running 12.2 i386 inadvertently has its time set 1 year into the future and just been started (it usually is off)
- There are periodic "showmount -e" queries running between all active machines, therefore also betwen the VM and the physical machine

Result:
- the VM crashes twice within approx. 15 minutes
- unfortunately, no crash dumps saved

The issue with the machine which had its clock set 1 year into the future is the only thing I can think of which changed on the network just before the VM crashed.

-- Martin