Linux-kernel mailing list archive 2000-01,: Re: [RFC] pte equality tests

# Re: [RFC] pte equality tests

Brian Parris (netgod@in.freei.net)
Mon, 3 Jan 2000 00:24:29 +0200

- Messages sorted by: [ date ][ thread ][ subject ][ author ]
- Next message: Alan Cox: "Re: 2.2.14pre17 hangup with SMP during ifconfig"
- Previous message: Pavel Machek: "Re: Unexecutable Stack / Buffer Overflow Exploits..."

On Fri, 31 Dec 1999, David S. Miller wrote:

> Date: Fri, 31 Dec 1999 20:34:31 -0500
> From: Jeff Dike <jdike@karaya.com>
>
> So, would it be reasonable to replace the equality tests with a test like
>
> if(!pte_really_changed(*page_table, pte)){
> }
>
> where pte_really_changed looks something like:
>
> #define pte_really_changed(pte1, pte2) \
> ((pte_val(pte1) ^ pte_val(pte2)) != _PAGE_ACCESSED)
>
> Your analysis is correct (it can/does happen), however I don't
> think it happens often enough to worry about it.
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
i hope the above attitude never becomes popular in linux as it seems to be
better suited to many MS products

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.rutgers.edu
Please read the FAQ at http://www.tux.org/lkml/

- Next message: Alan Cox: "Re: 2.2.14pre17 hangup with SMP during ifconfig"
- Previous message: Pavel Machek: "Re: Unexecutable Stack / Buffer Overflow Exploits..."