Re: [Alacrityvm-devel] [PATCH v2 2/4] KVM: introduce "xinterface"API for external interaction with guests

[Avi Kivity]

On 10/06/2009 08:18 PM, Ira W. Snyder wrote:
> The limitation I have is that memory made available from the host system
> (PCI card) as PCI BAR1 must not be migrated around in memory. I can only
> change the address decoding to hit a specific physical address. AFAIK,
> this means it cannot be userspace memory (since the underlying physical
> page could change, or it could be in swap), and must be allocated with
> something like __get_free_pages() or dma_alloc_coherent().
>    

Expose it as /dev/something (/dev/mem, /sys/.../pci/...) and mmap() it, 
and it becomes non-pageable user memory.

Not sure about dma_alloc_coherent(), that is meaningless on x86.

--
Do not meddle in the internals of kernels, for they are subtle and quick to panic.

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