Re: [PATCH 1/2] x86: limit page type width

From: "Jan Beulich" <JBeulich@suse.com>
To: Andrew Cooper <andrew.cooper3@citrix.com>
Cc: xen-devel <xen-devel@lists.xenproject.org>
Subject: Re: [PATCH 1/2] x86: limit page type width
Date: Wed, 31 May 2017 04:09:58 -0600	[thread overview]
Message-ID: <592EB296020000780015E27E@prv-mh.provo.novell.com> (raw)
In-Reply-To: <c130e90e-3aa9-712c-9ed5-b9389b9940b6@citrix.com>

>>> On 31.05.17 at 12:01, <andrew.cooper3@citrix.com> wrote:
> On 31/05/17 08:14, Jan Beulich wrote:
>> There's no reason to burn 4 bits on page type when we only have 7 types
>> (plus "none") at present. This requires changing one use of
>> PGT_shared_page, which so far assumed that the type is both a power of
>> 2 and the only type with the high bit set.
>>
>> Signed-off-by: Jan Beulich <jbeulich@suse.com>
> 
> Any particular reason why you reverse the order of shared and writeable?

I've become very used to know that type 7 is "writable", and since
there was a gap at 6 it seemed reasonable to put "shared" there
instead of shifting both down by one.

> Either way, Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>

Thanks.

Jan

_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xen.org
https://lists.xen.org/xen-devel