xen-devel.lists.xenproject.org archive mirror
 help / color / mirror / Atom feed
From: Keir Fraser <keir.fraser@eu.citrix.com>
To: "Jiang, Yunhong" <yunhong.jiang@intel.com>,
	Tim Deegan <Tim.Deegan@eu.citrix.com>
Cc: "xen-devel@lists.xensource.com" <xen-devel@lists.xensource.com>
Subject: Re: one question to p2m table entry type
Date: Wed, 5 May 2010 10:21:56 +0100	[thread overview]
Message-ID: <C806F744.13560%keir.fraser@eu.citrix.com> (raw)
In-Reply-To: <789F9655DD1B8F43B48D77C5D30659731E417BBD@shsmsx501.ccr.corp.intel.com>

I think you're right, and this was probably too subtle to pick up in the
initial phase of code cleanup when non-pae support was removed. I think
Tim's away for a week or two now so you may not get a definitive response
for a little while.

 -- Keir

On 05/05/2010 09:17, "Jiang, Yunhong" <yunhong.jiang@intel.com> wrote:

> Tim/Keir, I noticed that when translatiing p2m table type and p2m pte entry
> flags, there are difference handling for x86_64 and x32 like:
> 
> in p2m_type_to_flags:
> #ifdef __x86_64__
>     flags = (unsigned long)(t & 0x3fff) << 9;
> #else
>     flags = (t & 0x7UL) << 9;
> #endif
> 
> in p2m_flags_to_type:
>     /* Type is stored in the "available" bits */
> #ifdef __x86_64__
>     return (flags >> 9) & 0x3fff;
> #else
>     return (flags >> 9) & 0x7;
> 
> But since we don't support pure 32 bit xen hypervisor any more, and for 32
> PAE, we are sure have enough bit to keep these flags, why do we need these
> special handling? Are there any special reason for it?
> 
> Thanks
> --jyh
> 
> _______________________________________________
> Xen-devel mailing list
> Xen-devel@lists.xensource.com
> http://lists.xensource.com/xen-devel

  reply	other threads:[~2010-05-05  9:21 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2010-05-05  8:17 one question to p2m table entry type Jiang, Yunhong
2010-05-05  9:21 ` Keir Fraser [this message]
2010-05-18 11:04 ` Tim Deegan
2010-05-18 12:28   ` Keir Fraser
2010-05-18 18:32   ` Jeremy Fitzhardinge
2010-05-19  3:02     ` Jiang, Yunhong

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=C806F744.13560%keir.fraser@eu.citrix.com \
    --to=keir.fraser@eu.citrix.com \
    --cc=Tim.Deegan@eu.citrix.com \
    --cc=xen-devel@lists.xensource.com \
    --cc=yunhong.jiang@intel.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).