From: Muli Ben-Yehuda <muli@il.ibm.com>
To: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>,
Yinghai Lu <Yinghai.Lu@Sun.COM>, Andi Kleen <ak@suse.de>,
Andrew Morton <akpm@linux-foundation.org>,
Vivek Goyal <vgoyal@in.ibm.com>,
Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] x86-64: disable the GART before allocate aperture
Date: Fri, 22 Jun 2007 14:45:39 -0700 [thread overview]
Message-ID: <20070622214539.GA8795@rhun.ibm.com> (raw)
In-Reply-To: <m18xabbrp6.fsf@ebiederm.dsl.xmission.com>
On Fri, Jun 22, 2007 at 03:32:53PM -0600, Eric W. Biederman wrote:
> Alan Cox <alan@lxorguk.ukuu.org.uk> writes:
>
> > You've got mapped live gart pages from the previous kernel. Even
> > if you disable the gart before a memset you may well have the
> > video card using gart translations and possibly live IOMMU
> > mappings for devices using it via bus mastering - and those will
> > cause you MCE exceptions with a corrupt cpu context flag (ie not
> > nicely recoverable).
>
> The original plan (which we have not followed up on). Was to
> reserve a chunk of any iommu for the kexec on panic kernel. Then to
> just have the second kernel use that unused chunk. This is how we
> treat the normal memory space and it seems a nice and simple
> approach to this kind of problem.
>
> For a normal kexec we should shut everything down before the kernel
> transition so it should not be an issue.
>
> YH do you think you can look at simply reserving a portion of the
> iommu? And having the kexec on panic kernel use the reserved
> portion?
How would this work with an isolation capable IOMMU which has
different address spaces for different devices? (e.g., Calgary which
is in mainline, Intel's VT-d which is coming soon, etc).
Cheers,
Muli
next prev parent reply other threads:[~2007-06-22 21:46 UTC|newest]
Thread overview: 41+ messages / expand[flat|nested] mbox.gz Atom feed top
2007-06-22 19:19 [PATCH] x86-64: disable the GART before allocate aperture Yinghai Lu
2007-06-22 19:31 ` Muli Ben-Yehuda
2007-06-22 19:38 ` Yinghai Lu
2007-06-22 19:49 ` Yinghai Lu
2007-06-22 20:33 ` Alan Cox
2007-06-22 21:28 ` Andi Kleen
2007-06-22 21:38 ` Yinghai Lu
2007-06-22 21:41 ` Eric W. Biederman
2007-06-22 21:32 ` Eric W. Biederman
2007-06-22 21:45 ` Muli Ben-Yehuda [this message]
2007-06-22 21:59 ` Yinghai Lu
2007-06-22 22:19 ` Alan Cox
2007-06-22 22:32 ` Eric W. Biederman
2007-06-22 22:43 ` Yinghai Lu
2007-06-22 22:54 ` Alan Cox
2007-06-22 22:57 ` Yinghai Lu
2007-06-22 23:04 ` Alan Cox
2007-06-22 23:14 ` Eric W. Biederman
2007-06-23 0:14 ` Andi Kleen
2007-06-23 0:27 ` Yinghai Lu
2007-06-23 0:35 ` Muli Ben-Yehuda
2007-06-23 0:38 ` Andi Kleen
2007-06-23 2:34 ` [PATCH] x86-64: disable the GART in shutdown Yinghai Lu
2007-06-23 10:39 ` Muli Ben-Yehuda
2007-06-23 10:59 ` Andi Kleen
2007-06-23 11:09 ` Muli Ben-Yehuda
2007-06-23 11:08 ` Andi Kleen
2007-06-25 0:18 ` Yinghai Lu
2007-06-23 16:52 ` Andrew Morton
2007-06-25 0:22 ` Yinghai Lu
2007-06-25 2:10 ` Muli Ben-Yehuda
2007-06-25 19:34 ` [PATCH] x86-64: disable the GART in shutdown v2 Yinghai Lu
2007-06-25 19:41 ` Muli Ben-Yehuda
2007-06-25 19:52 ` Yinghai Lu
2007-06-25 19:56 ` Muli Ben-Yehuda
2007-06-25 21:48 ` [PATCH 1/2] x86-64: disable the GART in shutdown Yinghai Lu
2007-06-25 21:49 ` [PATCH 2/2] x86_84: move iommu declaration from proto to iommu.h Yinghai Lu
2007-06-26 11:43 ` Muli Ben-Yehuda
2007-06-23 9:08 ` [PATCH] x86-64: disable the GART before allocate aperture Alan Cox
2007-06-23 11:12 ` Vivek Goyal
2007-06-23 13:14 ` Andi Kleen
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=20070622214539.GA8795@rhun.ibm.com \
--to=muli@il.ibm.com \
--cc=Yinghai.Lu@Sun.COM \
--cc=ak@suse.de \
--cc=akpm@linux-foundation.org \
--cc=alan@lxorguk.ukuu.org.uk \
--cc=ebiederm@xmission.com \
--cc=linux-kernel@vger.kernel.org \
--cc=vgoyal@in.ibm.com \
/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;
as well as URLs for NNTP newsgroup(s).