From owner-freebsd-fs@FreeBSD.ORG  Thu Feb 22 15:12:29 2007
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Date: Thu, 22 Feb 2007 15:53:36 +0100
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To: Eric Anderson <anderson@freebsd.org>
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Cc: freebsd-fs@freebsd.org
Subject: Re: The patch delete no umount eject flash disk freebsd panic
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Eric Anderson schrieb:

> So what happens when you have a regular drive fail then?  Or yank a SATA 
> or other drive out from under the OS?
> 
> This patch seems awfully dangerous to me..

I don't want to disagree. This is dangerous. Seriously, I have another 
thought: is it less dangerous to risk data loss or corruption of other 
file systems that are not affected just because we killed the whole 
system immediately?

I had this problem several times: device removed and access to one of 
its file systems causes the death of the machine. For example:

   - insert a disk into floppy disk drive
   - mount its file system
   - remove floppy disk (oops!)
   - insert it again (quickly, before anything notice)
   - umount the file system
   => kernel panic

The result is that other well running file systems on this machine 
became corrupt or inconsistent. This issue definitively needs a 
solution. I understand if you don't want to ignore and override the 
disappearance of a file system, but in this case we probably either need 
a kind of "soft panic" that tries to unmount other file systems before 
death blow, a safe way to force unmounting a broken file system without 
kernel panic explicitely or a configurable case differentiation.

Regards
Björn