This is an archived copy of the Xen.org mailing list, which we have preserved to ensure that existing links to archives are not broken. The live archive, which contains the latest emails, can be found at http://lists.xen.org/
Home Products Support Community News


Re: [Xen-devel] [PATCH] linux-2.6.18/x86_64: remove an inapplicable fea

To: Jan Beulich <JBeulich@xxxxxxxxxx>
Subject: Re: [Xen-devel] [PATCH] linux-2.6.18/x86_64: remove an inapplicable feature flag
From: Jeremy Fitzhardinge <jeremy@xxxxxxxx>
Date: Wed, 03 Nov 2010 08:35:51 -0400
Cc: "xen-devel@xxxxxxxxxxxxxxxxxxx" <xen-devel@xxxxxxxxxxxxxxxxxxx>
Delivery-date: Wed, 03 Nov 2010 05:37:46 -0700
Envelope-to: www-data@xxxxxxxxxxxxxxxxxxx
In-reply-to: <4CD135CC02000078000205E1@xxxxxxxxxxxxxxxxxx>
List-help: <mailto:xen-devel-request@lists.xensource.com?subject=help>
List-id: Xen developer discussion <xen-devel.lists.xensource.com>
List-post: <mailto:xen-devel@lists.xensource.com>
List-subscribe: <http://lists.xensource.com/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=subscribe>
List-unsubscribe: <http://lists.xensource.com/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=unsubscribe>
References: <4CD1327D02000078000205D6@xxxxxxxxxxxxxxxxxx> <4CD135CC02000078000205E1@xxxxxxxxxxxxxxxxxx>
Sender: xen-devel-bounces@xxxxxxxxxxxxxxxxxxx
User-agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv: Gecko/20101027 Fedora/3.1.6-1.fc13 Lightning/1.0b3pre Thunderbird/3.1.6
On 11/03/2010 05:13 AM, Jan Beulich wrote:
>>>> On 03.11.10 at 09:59, "Jan Beulich" <JBeulich@xxxxxxxxxx> wrote:
>> Signed-off-by: Jan Beulich <jbeulich@xxxxxxxxxx>
>> --- a/arch/x86_64/kernel/head-xen.S
>> +++ b/arch/x86_64/kernel/head-xen.S
>> @@ -206,6 +206,6 @@
>>      ELFNOTE(Xen, XEN_ELFNOTE_ENTRY,          .quad,  startup_64)
>>      ELFNOTE(Xen, XEN_ELFNOTE_HYPERCALL_PAGE, .quad,  hypercall_page)
>>      ELFNOTE(Xen, XEN_ELFNOTE_L1_MFN_VALID,   .quad,  
>> -    ELFNOTE(Xen, XEN_ELFNOTE_FEATURES,       .asciz, 
>> "writable_page_tables|writable_descriptor_tables|auto_translated_physmap|pae_pgdir_above_4gb|supervisor_mode_kernel")
>> +    ELFNOTE(Xen, XEN_ELFNOTE_FEATURES,       .asciz, 
>> "writable_page_tables|writable_descriptor_tables|auto_translated_physmap|supervisor_mode_kernel")
>>      ELFNOTE(Xen, XEN_ELFNOTE_LOADER,         .asciz, "generic")
> If the flag was removed from the pv-ops 64-bit kernel too, we could
> even start warning about inapplicable flags in hypervisor/tools.
> What puzzles me more though is that the pv-ops kernel requires
> the writable_page_tables feature. Why is that?

It did in the very early days, but it hasn't used it since converting to
PV MMU (couldn't, since it doesn't exist any more).  It lists
"!writable_page_table", which I read as meaning "writable page tables
not supported"; does it actually mean "must"?


Xen-devel mailing list