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Date: Wed, 6 May 2015 14:28:12 -0700
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Subject: Re: What's required to make removal of a mounted USB stick safe?
From: NGie Cooper <yaneurabeya@gmail.com>
To: Ryan Stone <rysto32@gmail.com>
Cc: "freebsd-hackers@freebsd.org" <freebsd-hackers@freebsd.org>
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On Wed, May 6, 2015 at 1:49 PM, Ryan Stone <rysto32@gmail.com> wrote:
> Currently FreeBSD stands a fair chance at panicking if a mounted USB drive
> is removed while I/O is in flight.  Does anybody know what work is involved
> to have the kernel safely recover from this case?  Losing data from the
> drive is expected of course but there's no reason that the entire kernel
> has to crash.
>
> A co-worker has been looking at this but I don't feel that we understand
> the problem well enough to produce a real fix.  All that we've been doing
> so far is papering over the explicit panics without having a full
> understanding of what we're doing.

What version are you working on and how is the USB stick mounted (/, /mnt, etc)?
Thanks!