From: Matthew Garrett <mjg59@srcf.ucam.org>
To: "H. Peter Anvin" <hpa@zytor.com>
Cc: linux-kernel@vger.kernel.org, x86@kernel.org, matt.fleming@intel.com
Subject: Re: [PATCH] EFI: Only set regions uncacheable if they support it
Date: Thu, 15 Mar 2012 14:54:03 +0000 [thread overview]
Message-ID: <20120315145403.GA5321@srcf.ucam.org> (raw)
In-Reply-To: <4F62011D.4000708@zytor.com>
On Thu, Mar 15, 2012 at 07:47:57AM -0700, H. Peter Anvin wrote:
> WTF?! That should be UC at all times... it isn't even WC-capable.
> Furthermore, we may need this region (assuming there is actually a video
> card there.)
I don't think we'll ever use this region on UEFI. What I have from Intel
is:
"It looks like this is happening when the kernel iterates over the
various regions in the EFI memory map. It hits a region starting at
0xA0000 and attempts to do a CLFLUSH instruction on that address. This
is explicitly forbidden by the SAD in (codename), thus the Machine
Check."
> What do the fixed MTRRs look like?
Unsure. I'll try to find out.
--
Matthew Garrett | mjg59@srcf.ucam.org
next prev parent reply other threads:[~2012-03-15 14:54 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-03-15 13:56 Matthew Garrett
2012-03-15 14:00 ` H. Peter Anvin
2012-03-15 14:07 ` Matthew Garrett
2012-03-15 14:17 ` H. Peter Anvin
2012-03-15 14:24 ` Matthew Garrett
2012-03-15 14:28 ` H. Peter Anvin
2012-03-15 14:33 ` Matthew Garrett
2012-03-15 14:36 ` H. Peter Anvin
2012-03-15 14:42 ` Matthew Garrett
2012-03-15 14:47 ` H. Peter Anvin
2012-03-15 14:54 ` Matthew Garrett [this message]
2012-03-15 14:51 ` Alan Cox
2012-03-15 14:54 ` Alan Cox
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20120315145403.GA5321@srcf.ucam.org \
--to=mjg59@srcf.ucam.org \
--cc=hpa@zytor.com \
--cc=linux-kernel@vger.kernel.org \
--cc=matt.fleming@intel.com \
--cc=x86@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox
all inboxes | Powered by JetHome®