linux-kernel - Re: [RFC PATCH 00/12] PAT 64b: PAT support for X86

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]

Date:	Fri, 14 Dec 2007 14:00:15 -0800
From:	"Siddha, Suresh B" <suresh.b.siddha@...el.com>
To:	Dave Airlie <airlied@...net.ie>
Cc:	venkatesh.pallipadi@...el.com, ak@....de, ebiederm@...ssion.com,
	rdreier@...co.com, torvalds@...ux-foundation.org, gregkh@...e.de,
	davej@...hat.com, mingo@...e.hu, tglx@...utronix.de, hpa@...or.com,
	akpm@...ux-foundation.org, arjan@...radead.org,
	jesse.barnes@...el.com, linux-kernel@...r.kernel.org
Subject: Re: [RFC PATCH 00/12] PAT 64b: PAT support for X86_64

On Fri, Dec 14, 2007 at 12:28:25AM +0000, Dave Airlie wrote:
> Yes, the main use for GPUs is to have RAM pages mapped WC, and placed into 
> a GART on the GPU side, currently for Intel IGD we are okay as the CPU can 
> access the GPU GART aperture, but other chips exist where this isn't 
> possible, I think poulsbo and possible some of the AMD IGPs..

Ok. So how is it working today on these platforms with no PAT support.
Open source drivers use UC or WB on these platforms? As this RAM is not
contiguous, one can't use MTRRs to set WC. Right?

Well, if WC is needed for RAM, then we have to address it too.

thanks,
suresh
--
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/