From owner-freebsd-arch  Wed May 16 13:51: 6 2001
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To: dillon@earth.backplane.com
Cc: arch@FreeBSD.ORG
Subject: Re: on load control / process swapping
From: Tor.Egge@fast.no
In-Reply-To: Your message of "Wed, 16 May 2001 13:31:46 -0700 (PDT)"
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>     Ok, I've done a quick once-over of the patch and I have a question:
>     What happens if you've just written that file normally and there are
>     still some uncomitted dirty buffers associated with it, and you then
>     do an O_DIRECT read of the file?  Do you get the old data or the new
>     data?

Currently, you get the old data.  That's both semantically incorrect
and a security hole.  Some check for dirty buffers should be made if
the OBJ_MIGHTBEDIRTY flag is set on the vm object.

- Tor Egge

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