[libvirt] qemu driver fails to load on Xen after be0782e1

[Michal Privoznik]

On 11.08.2014 11:16, Daniel P. Berrange wrote:
> On Tue, Aug 05, 2014 at 11:16:53AM -0600, Jim Fehlig wrote:
>> Jim Fehlig wrote:
>>> Until recently, the qemu driver has always succeeded in loading even on
>>> a system booted to Xen.  Commit be0782e1 broke this, hence libvirtd no
>>> longer loads
>>>
>>> xendom0 # /usr/sbin/libvirtd -l
>>> 2014-08-04 22:27:31.586+0000: 35859: info : libvirt version: 1.2.8
>>> 2014-08-04 22:27:31.586+0000: 35859: error :
>>> virFileGetDefaultHugepageSize:2958 : internal error: Unable to parse
>>> /proc/meminfo
>>> 2014-08-04 22:27:31.586+0000: 35859: error : virStateInitialize:749 :
>>> Initialization of QEMU state driver failed: internal error: Unable to
>>> parse /proc/meminfo
>>> 2014-08-04 22:27:31.586+0000: 35859: error : daemonRunStateInit:922 :
>>> Driver state initialization failed
>>>
>>> Problem is the Xen kernel does not provide any huge page info in
>>> /proc/meminfo
>>>
>>> xendom0 # cat /proc/meminfo | grep -i huge
>>> xendom0 #
>>>
>>
>> BTW, I think this would be the case for any kernel with
>> CONFIG_HUGETLB_PAGE turned off.
>
> Yes, we should be robust to this situation.

And as of d26e810838fad we are fault tolerant.

>
>>> Michal, short of always building with '--without-qemu' on a Xen system,
>>> is it possible to make detection of huge pages less fatal wrt loading
>>> the qemu driver?
>>>
>>
>> E.g. assume zero/default for entries not present?
>
> If the dirs / files don't exist, we should just not report any huge
> page info at all.
>
> Regards,
> Daniel
>

Michal