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Re: [Xen-devel] tmem and construct_dom0 memory allocation race

To: Dulloor <dulloor@xxxxxxxxx>, Dan Magenheimer <dan.magenheimer@xxxxxxxxxx>
Subject: Re: [Xen-devel] tmem and construct_dom0 memory allocation race
From: Keir Fraser <keir.fraser@xxxxxxxxxxxxx>
Date: Tue, 22 Jun 2010 08:38:21 +0100
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On 22/06/2010 08:17, "Dulloor" <dulloor@xxxxxxxxx> wrote:

> Hi Keir, You are right .. there is no race. I spent some time
> debugging this. The problem is that a zero-order allocation (from
> alloc_chunk, for the last dom0 page) fails with tmem on (in
> alloc_heap_pages), even though there are pages available in the heap.
> I don't think tmem really intends to get triggered so early. What do
> you think ?

That's one for Dan to comment on.

> Also, on an unrelated note, the number of pages estimated for dom0
> (nr_pages) could be off by (opt_dom0_vcpus/16) pages, due to the
> perdomain_pt_page allocation (in vcpu_initialise).

You could send a patch for this.

 -- Keir



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