From nobody Sun Dec 26 19:23:38 2021
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Date: Sun, 26 Dec 2021 11:23:38 -0800
From: bob prohaska <fbsd@www.zefox.net>
To: freebsd-arm@freebsd.org
Subject: Hot-plugging microSD on Raspberry Pi under FreeBSD
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Are there any special protocols to observe when hot-plugging
microSD cards on Raspberry Pi when FreeBSD is up and running?
Electrically it's claimed to be ok in this thread by one "jdb":
https://forums.raspberrypi.com/viewtopic.php?t=281249
so I'm asking about how the FreeBSD software might react. 

Obviously filesystems have to be gracefully unmounted, but is
that all? Can the kernel be "aware" of an unused device and
get confused if it goes away?

Thanks for reading,

bob prohaska