linux-kernel - Re: [PATCH] x86: mtrr cleanup for converting continuous to discrete layout v2

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20080428130826.GH27997@elte.hu>
Date:	Mon, 28 Apr 2008 15:08:26 +0200
From:	Ingo Molnar <mingo@...e.hu>
To:	yhlu.kernel@...il.com
Cc:	Andrew Morton <akpm@...ux-foundation.org>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
	"H. Peter Anvin" <hpa@...or.com>,
	Thomas Gleixner <tglx@...utronix.de>,
	Arjan van de Ven <arjan@...radead.org>
Subject: Re: [PATCH] x86: mtrr cleanup for converting continuous to
	discrete layout v2


* Yinghai Lu <yhlu.kernel.send@...il.com> wrote:

> some BIOS like to use continus MTRR layout, and X driver can not add 
> WB entries for graphical cards when 4g or more RAM installed.
> 
> the patch will change MTRR to discrete.
> 
> mtrr_chunk_size= could be used to have smaller continuous block to 
> hold holes. default is 256m, could be set according to size of 
> graphics card memory.

hm.

> +static int disable_mtrr_cleanup;

i think this should be default-disabled. Touching MTRRs on a live system 
could interact with SMM and MCE handlers.

how relevant is this feature with modern Xorg? I thought modern Xorg 
would get its mappings via /sys, hence it would not have to touch MTRRs 
at all.

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