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Subject: Re: FreeBSD is too filesystem errors sensitive
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cronfy wrote:
> Hello.
> 
> Please forgive me for probably a very stupid question. But why is 
> FreeBSD so sensitive to filesystem errors that it ends up with panics 
> like 'freeing free block' or 'ffs_valloc: dup alloc'? I just can't get 
> it. Failed to allocate vnode? Go allocate another one! Freeing free 
> block? Leave it free then! I understand these situations should never 
> happen, but the hell why is it required to panic and kill everything 
> that would be working happily even if something very disasterous happen 
> to /backup partition, in example?
> 
> Would be very appreciated if someone could explain that... thanks.

Probably because UFS is not designed to be a backup file system but a 
working one :)

All those errors indicate file system corruption. To protect other data 
from getting corrupted (e.g. by invalid pointers or calculations), the 
kernel panics.