From mboxrd@z Thu Jan  1 00:00:00 1970
From: Keir Fraser <keir.xen@gmail.com>
Subject: Re: [PATCH] x86: drop setup_idle_pagetable()
Date: Wed, 12 Jun 2013 16:25:02 +0100
Message-ID: <CDDE515E.29DF2%keir.xen@gmail.com>
References: <51B89066.50605@eu.citrix.com>
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To: George Dunlap <george.dunlap@eu.citrix.com>, Jan Beulich <JBeulich@suse.com>
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On 12/06/2013 16:14, "George Dunlap" <george.dunlap@eu.citrix.com> wrote:

> On 12/06/13 15:59, Jan Beulich wrote:
>> With vcpu->domain->arch.perdomain_l3_pg no longer getting set up for
>> the idle domain, this creates an invalid L4 entry (due to translating
>> a NULL struct page_info pointer to a physical address).
>> 
>> Signed-off-by: Jan Beulich <jbeulich@suse.com>
> 
> I don't think it buys very much awesomeness, but it should certainly be
> pretty low risk.
> 
> Acked-by: George Dunlap <george.dunlap@eu.citrix.com>

Pagetable entries pointing into the wilderness are actively dangerous. At
the very least they can cause cache-attribute collisions. This is a real bug
fix.

 -- Keir