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Patrick Lauer wrote: |
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[snip] |
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>> Also it seems that you could have more than one of these privilidged |
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>> osses installed at the same time sharing different parts of the |
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>> hardware. |
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>> |
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> in theory yes, I don't know how well that is supported |
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> |
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[snip] |
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only one os (dom0) access the hardware, it run at ring 0, on 32 bit |
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machines there are 5 rings[#1], the other kernels (domU) run at ring 1, |
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the userspace software always run at ring 5. |
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There are a set of cpu instruction that help using interrupts to |
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virtualize the hardware access (also prior to vt). |
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For tecnical reasons amd64 only kept ring 0 and 5 making it impossible |
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for kernels like xen to continue working like before. |
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Both 32 bit and 64 bit, intel or amd are developing a tecnology to help |
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virtualization "vt" for intel "pacifica" for amd [#2][#3]. |
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[#2] should explain the concept deepere and better, also for what vt does. |
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Xen will take advantage from both I think. |
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Don't know the others, so only these 2 ˆcents ;) |
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[resnip] |
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[#1] the number may differ from 5 due to my broken memory |
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[#2] |
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http://www.itarchitect.com/shared/article/showArticle.jhtml?articleId=172302134 |
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[#3] http://www.google.it/search?q=amd+vt+virtualization |
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