From mboxrd@z Thu Jan  1 00:00:00 1970
From: Juergen Gross <jgross@suse.com>
Subject: Re: Can't create small PV guest anymore (64MB)
Date: Mon, 8 Feb 2016 12:50:43 +0100
Message-ID: <56B88113.5010202@suse.com>
References: <20160208111810.GA1810@perard.uk.xensource.com>
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To: Anthony PERARD <anthony.perard@citrix.com>, Xen Devel <xen-devel@lists.xen.org>, Ian Campbell <ian.campbell@citrix.com>, Ian Jackson <Ian.Jackson@eu.citrix.com>, Wei Liu <wei.liu2@citrix.com>
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On 08/02/16 12:18, Anthony PERARD wrote:
> Hi,
> 
> I used to be able to boot a guest with 64MB, but now the minimum required
> to boot it seams to be 85MB. It's a PV guest used and lauched by OpenStack
> with there test suite. You can find the image at [1].
> 
> The guest failed to boot with this error message:
> xc: error: panic: xc_dom_x86.c:147: count_pgtables: not enough memory for initial mapping (0x5498 > 0x4000): Out of memory
> libxl: error: libxl_dom.c:655:libxl__build_dom: xc_dom_build_image failed: No such file or directory
> ...
> 
> It still works on commit 6853c9b but guest creation fail on commit d07f63f.
> In between, there is a patch series from Juergen that change libxc. I have
> not check which patch in particular broke guest creation.
> 
> How can we boot this guest [1] with only 64MB of memory like it was working
> before?
> 
> [1] http://download.cirros-cloud.net/0.3.4/cirros-0.3.4-x86_64-uec.tar.gz
> 

Could you please provide:

- guest configuration file
- output of "xl -v create ..."


Juergen