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Date: Sun, 8 Mar 2015 17:50:46 -0500
From: "Matthew D. Fuller" <fullermd@over-yonder.net>
To: Steven Hartland <killing@multiplay.co.uk>
Subject: Re: RFC: Pass TRIM through GELI
Message-ID: <20150308225046.GS1742@over-yonder.net>
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On Sun, Mar 08, 2015 at 10:40:03PM +0000 I heard the voice of
Steven Hartland, and lo! it spake thus:
> 
> Given GEIL is all about security translating the delete to a noop
> results in a pretty serious security issue I would say as it will
> leave data which he user intended to be removed present on the
> device.

But we're not translating it to anything; we're just passing it along.
Certainly in my testing (Virtualbox-provided ada0, which doesn't TRIM,
and md(4), which does) ufs and zfs seem to get the message just fine.
If a poorly-behaved filesystem ignores the "I don't support that"
message from our provider (SSD, hard drive, md(4), whatever), wouldn't
it ignore us just the same?


-- 
Matthew Fuller     (MF4839)   |  fullermd@over-yonder.net
Systems/Network Administrator |  http://www.over-yonder.net/~fullermd/
           On the Internet, nobody can hear you scream.