public inbox for linux-acpi@vger.kernel.org
 help / color / mirror / Atom feed
From: "H. Peter Anvin" <hpa@zytor.com>
To: Pekka Enberg <penberg@kernel.org>
Cc: Yinghai Lu <yinghai@kernel.org>,
	Thomas Gleixner <tglx@linutronix.de>, Ingo Molnar <mingo@elte.hu>,
	Andrew Morton <akpm@linux-foundation.org>,
	Tejun Heo <tj@kernel.org>, Thomas Renninger <trenn@suse.de>,
	Tang Chen <tangchen@cn.fujitsu.com>,
	linux-kernel@vger.kernel.org, Jacob Shin <jacob.shin@amd.com>,
	"Rafael J. Wysocki" <rjw@sisk.pl>,
	linux-acpi@vger.kernel.org
Subject: Re: [PATCH v2 08/20] x86, ACPI: Find acpi tables in initrd early from head_32.S/head64.c
Date: Thu, 04 Apr 2013 13:25:37 -0700	[thread overview]
Message-ID: <515DE1C1.6080000@zytor.com> (raw)
In-Reply-To: <CAOJsxLG2Qg7vmLWirWK-GOBp65NxogGcAU5guoVphDu2G=BsjA@mail.gmail.com>

On 03/10/2013 03:25 AM, Pekka Enberg wrote:
> 
> What is preventing us from making the 64-bit variant also work in flat
> mode to make the code consistent and not hiding the differences under
> the rug? What am I missing here?
> 

There is no such thing as "flat mode" in 64-bit mode.  We use a #PF
handler to emulate it, but we add the normal kernel offset when doing so.

In the 32-bit case the problem is that the kernel offset is not
available while in linear mode.  It *could* be created using segment
bases, but that would break Xen, I'm pretty sure, and possibly some
other too-clever environments.

	-hpa



  parent reply	other threads:[~2013-04-04 20:26 UTC|newest]

Thread overview: 23+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <1362897887-30808-1-git-send-email-yinghai@kernel.org>
2013-03-10  6:44 ` [PATCH v2 03/20] x86, ACPI, mm: Kill max_low_pfn_mapped Yinghai Lu
2013-04-04 17:36   ` Tejun Heo
2013-04-04 18:20     ` Yinghai Lu
2013-03-10  6:44 ` [PATCH v2 04/20] x86, ACPI: Increase override tables number limit Yinghai Lu
2013-04-04 17:50   ` Tejun Heo
2013-04-04 18:03     ` Yinghai Lu
2013-03-10  6:44 ` [PATCH v2 05/20] x86, ACPI: Split acpi_initrd_override to find/copy two functions Yinghai Lu
2013-04-04 18:07   ` Tejun Heo
2013-04-04 19:29     ` Yinghai Lu
2013-03-10  6:44 ` [PATCH v2 06/20] x86, ACPI: Store override acpi tables phys addr in cpio files info array Yinghai Lu
2013-04-04 18:27   ` Tejun Heo
2013-04-04 18:30     ` Tejun Heo
2013-04-04 19:40       ` Yinghai Lu
2013-04-04 20:03     ` Yinghai Lu
2013-03-10  6:44 ` [PATCH v2 07/20] x86, ACPI: Make acpi_initrd_override_find work with 32bit flat mode Yinghai Lu
2013-04-04 18:35   ` Tejun Heo
2013-04-04 20:22     ` Yinghai Lu
2013-03-10  6:44 ` [PATCH v2 08/20] x86, ACPI: Find acpi tables in initrd early from head_32.S/head64.c Yinghai Lu
2013-03-10 10:25   ` Pekka Enberg
2013-03-10 16:47     ` Yinghai Lu
2013-03-10 17:42       ` H. Peter Anvin
2013-04-04 20:25     ` H. Peter Anvin [this message]
2013-03-10  6:44 ` [PATCH v2 16/20] x86, ACPI, numa, ia64: split SLIT handling out Yinghai Lu

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=515DE1C1.6080000@zytor.com \
    --to=hpa@zytor.com \
    --cc=akpm@linux-foundation.org \
    --cc=jacob.shin@amd.com \
    --cc=linux-acpi@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mingo@elte.hu \
    --cc=penberg@kernel.org \
    --cc=rjw@sisk.pl \
    --cc=tangchen@cn.fujitsu.com \
    --cc=tglx@linutronix.de \
    --cc=tj@kernel.org \
    --cc=trenn@suse.de \
    --cc=yinghai@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