linux-kernel - Re: [PATCH] EFI: Only set regions uncacheable if they support it

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: <4F61F5E6.8060509@zytor.com>
Date:	Thu, 15 Mar 2012 07:00:06 -0700
From:	"H. Peter Anvin" <hpa@...or.com>
To:	Matthew Garrett <mjg@...hat.com>
CC:	linux-kernel@...r.kernel.org, x86@...nel.org,
	matt.fleming@...el.com
Subject: Re: [PATCH] EFI: Only set regions uncacheable if they support it

On 03/15/2012 06:56 AM, Matthew Garrett wrote:
> The EFI memory region attributes field indicates whether the region can
> be mapped with various cache attributes. Our current implementation always
> marks regions uncacheable if they don't have the writeback support flag.
> This causes us to mark some regions uncacheable even if they don't
> indicate support for being uncacheable, triggering a clflush that may cause
> an MCE. Ensure we only do this for regions which support it.
> 
> Signed-off-by: Matthew Garrett <mjg@...hat.com>

Could you be specific as to what you're seeing in the field?  In
particular, what *do* these memory regions claim to support?

	-hpa

--
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/