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On Fri, 2008-07-11 at 22:22 +0100, Daniel P. Berrange wrote:<BR>
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<FONT COLOR="#000000">No, it only currently exposes VMX, SVM and PAE flags. Why exactly does</FONT>
<FONT COLOR="#000000">oVirt need the full set ? They're a forever changing set across processor</FONT>
<FONT COLOR="#000000">vendors and models and architectures which makes them fairly useless as</FONT>
<FONT COLOR="#000000">a whole. Specific applications typically only care about specific flags</FONT>
<FONT COLOR="#000000">hence we only exposed the ones clearly virt related so far</FONT>
<FONT COLOR="#000000">Daniel</FONT>
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Other flags would be useful for verifying migration support. If we pulled back the full set of flags then we'd have a baseline of information to use in working out which hosts a guest can be migrated to.<BR>
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For example if a guest is running on a host that has SSE2 then we wouldn't want to live migrate that to a host that didn't have this feature as it would probably choke. <BR>
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Obviously the logic behind working out what would and wouldn't work is horrific, but if we pull back this data at least we have a foundation to work on if we decided to go down that path.<BR>
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VMware has done some work on this - for example allowing the NX bit to be masked, and have added some more cpu bitmasking features in 3.5, but I've not looked too closely into them.<BR>
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Aic<BR>
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