Re: [Qemu-devel] [PATCH] ahci: map memory via device's address space instead of address_space_memory

[Paolo Bonzini]

Il 03/07/2014 10:43, Jan Kiszka ha scritto:
> On 2014-07-03 10:26, Le Tan wrote:
> > In map_page() in hw/ide/ahci.c, replace cpu_physical_memory_map() and
> > cpu_physical_memory_unmap() with dma_memory_map() and dma_memory_unmap(),
> > because ahci devices should not access memory directly but via their address
> > space. Add an AddressSpace parameter to map_page(). In order to call
> > map_page(), we should pass the AHCIState.as as the AddressSpace argument.
>
> BTW, when doing "git grep cpu_physical_memory_map hw", there are some
> more cases that should be checked (for x86). I suppose vhost is
> incompatible with an IOMMU, but plain virtio should work, same for vmxnet.

I think PPC folks explicitly wanted virtio to bypass the IOMMU, probably 
in order to get vhost running.  It seems like a bad idea to me, but who 
am I...

Paolo