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Subject: Re: [PATCH v1 1/8] virtio: Force only split mode with protected guest
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From:   Andi Kleen <ak@linux.intel.com>
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>
> I agree, but I want to know why indirect descriptor needs to be 
> disabled. The table can't be wrote by the device since it's not 
> coherent swiotlb mapping.

I had all kinds of problems with uninitialized entries in the indirect 
table. So I gave up on it and concluded it would be too difficult to secure.


-Andi