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From: Edward Tomasz Napierala <trasz@FreeBSD.org>
To: Andriy Gapon <avg@icyb.net.ua>
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Cc: FreeBSD-Current <freebsd-current@FreeBSD.org>, scottl@FreeBSD.org,
	Alexander Motin <mav@FreeBSD.org>, Mike Tancsa <mike@sentex.net>
Subject: Re: RFC: ATA to CAM integration patch (INTEL  DX58SO)
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On 0707T1312, Andriy Gapon wrote:
> >> Still the box does a panic when writing to the disk that has bad
> >> sectors on it. (I do newfs it between reboots).   Again, not sure if
> >> this is a "well, dont use a bad disk", but here is the panic again in
> >> case it shows something useful.
> >>
> > 
> > This is a 'don't use a bad disk' panic; FreeBSD UFS and VM simply can't
> > handle errors on reads or writes.
> 
> I think that this is not generally true, especially about reads.
> And wasn't there a FreeBSD Foundation sponsored project to fix panics caused by
> media going away? I think that panics on I/O errors are related to that.

Device going away is slightly different case, but I believe it shouldn't
be generally true, except for filesystems with softupdates enabled.  For
the most part, softupdates don't even try to handle I/O errors - they
just panic (e.g. "panic: softdep_move_dependencies: need merge code").

-- 
If you cut off my head, what would I say?  Me and my head, or me and my body?