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From: George Hartzell <hartzell@alerce.com>
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Date: Mon, 11 Nov 2013 20:40:45 -0800
To: "Steven Hartland" <smh@freebsd.org>
Subject: Re: Help with filing a [maybe] ZFS/mmap bug.
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 Andriy Gapon <avg@FreeBSD.org>
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Steven Hartland writes:
 > [...]
 > @George when you got corruption what did the files look like? I ask as
 > here I see lots of zeros as through the file size was correct but pretty
 > much blanked.

I had small changes.  I discussed it a bit here.

https://groups.google.com/forum/#!topic/fa.freebsd.stable/7xvY8ffWGpw

 > 
 > @avg what was your thinking behind what may be the issue here?
 > 
 > If this is a mmap bug in zfs its a pretty serious one given the amount
 > of silent corruption you can get.

Yeah, I have about 150 cd's to rerip someday.  Now I run flac -t to
validate them.

 > @re Although reported incidents appear to be rare as its silent data
 > corruption users may be blissfully unaware its happening. Given that
 > my gut feeling is this is serious enough that we need to get something
 > in place before 10 release, even if this is make ZFS report ENOTSUP
 > for mmap calls, would you agree?

Let me know if I can help.

g.