OT: just crashed two FreeBSD-11.1-RELEASE machines

[Polytropon]

On Tue, 13 Feb 2018 16:56:12 -0600, Valeri Galtsev wrote:
> I just crushed two (one at a time) FreeBSD-11.1-RELEASE machines. I 
> simply plugged my Sony video camera which was in the mode of exporting 
> its (msdos) filesystems over USB. Both machines have decent hardware, 
> plenty of resources. Regular user was logged in to X11. One of the 
> filesystems was mounted (the one holding AVCHD videos), and two seconds 
> later the machine started booting (like "crashed").
> 
> And now I'm sitting in prostration and thinking: What is that I will do 
> next?

Gather debugging data. Reduce automatisms and check each step
manually. Try to find out the exact "thing" that brought down
the system (it's hard to tell when X is running and doing its
"magic").

Many years ago, I had a similar problem, but when _detaching_
the camera from the system (internal filesystem was already
unmounted, and previous access to it went as expected)...
This was, I think, in FreeBSD 5 times, and after a system
update, the problem went away. So I never found out what the
actual problem was - but it could be reproduced any time,
even in single user mode: insert USB plug, system recognizes
da0 device (as intended), wait a few seconds, remove USB plug,
system panic, kernel crash. After update: regular "disconnect"
message, nothing else, system kept running.



-- 
Polytropon
Magdeburg, Germany
Happy FreeBSD user since 4.0
Andra moi ennepe, Mousa, ...