WARNING - OLD ARCHIVES

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/
   
 
 
Xen 
 
Home Products Support Community News
 
   
 

xen-devel

Re: [Xen-devel] loading IDT in xen?

To: "Jun Koi" <junkoi2004@xxxxxxxxx>
Subject: Re: [Xen-devel] loading IDT in xen?
From: "余上" <yusunn@xxxxxxxxx>
Date: Thu, 31 Jan 2008 14:56:23 +0800
Cc: xen-devel@xxxxxxxxxxxxxxxxxxx
Delivery-date: Wed, 30 Jan 2008 22:57:08 -0800
Dkim-signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:message-id:date:from:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; bh=qvHKDIZGGzaYGIhmpelNUmxdljMSc0m16g3OK7Jk80I=; b=wQQp4w6VwUbHWV8gOLj1TCGm1i1nKU16aO9O0K3GJUwtLMot/gVMp0JBu8mFrSQAN7t0fcgXtRlWkCmYkPs2BtI0ePrD6+gbAU8lXosO8ngeKNXqa1RUISUy4kuLOZuuJDKXaR7xNFPwvRO4i52Q5mHLKWFBwq6AiUDSSJ4wvyI=
Domainkey-signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; b=cGjV54W7MqL/uaWYxvEHWpx2l+FoxXu5KLFczWy+1LZ8oeD3wLQiprFOTC4+xIbPHL/CdiBshg7tlo2ka8nd51cZ3t3oh226WUNEVms7O87OFOUDzNTwd/Zl6S+5FlbhhXCun/+H2T0P0LaMmN9f0EbExYy20ISl8+O0kiQWNpM=
Envelope-to: www-data@xxxxxxxxxxxxxxxxxx
In-reply-to: <fdaac4d50801301946y89d1f08i80ff8d592795eb20@xxxxxxxxxxxxxx>
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/cgi-bin/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=subscribe>
List-unsubscribe: <http://lists.xensource.com/cgi-bin/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=unsubscribe>
References: <fdaac4d50801301946y89d1f08i80ff8d592795eb20@xxxxxxxxxxxxxx>
Sender: xen-devel-bounces@xxxxxxxxxxxxxxxxxxx
There is another IDTR reload in x86_32.S at line 15 , where the
protected mode IDT vectors are initialized with ignore_int handler
firstly. Then trap_init called from __xen_start will setup the formal
IDT vectors .

2008/1/31, Jun Koi <junkoi2004@xxxxxxxxx>:
> I am looking at the hypervisor code to see how Xen setup the IDT. But
> it seems that the code in protected mode reuses the real mode IDT?
>
> In arch/x86/boot/trampoline.S we have at several places:
>
> lidt bootsym(idt_48)
>
> And idt_48 is defined as:
>
> idt_48: .word 0,0,0 # base = limit = 0
>
> And in nowhere we initialize idt_48, which means idt_48 reuses real
> mode IDT table. However, real mode IDT table has different format than
> protected mode IDT, so this doesnt look to work for me.
>
> Definitely I miss something here. Anybody could enlighten me how IDT
> setting in protected mode work?
>
> Thanks,
> Jun
>
> _______________________________________________
> Xen-devel mailing list
> Xen-devel@xxxxxxxxxxxxxxxxxxx
> http://lists.xensource.com/xen-devel
>

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel

<Prev in Thread] Current Thread [Next in Thread>