On 09/29/2012 11:20 AM, liu ping fan wrote: > > Do we have iommus in qemu now,
We do, but they're hacked into the scsi layer, see hw/sun4m_iommu.c. I don't know if it's a standalone iommu on real hardware or whether it is part of the HBA. > since there are no separate phys_maps > for real address and dev's virt address, and I think the iommu is only > needed by host, not guest, so need not emulated by qemu. Eventually we will emulate iommus for x86 too, so we need to consider them. > If no, we > can just reject the nested DMA, and the c_p_m_rw() can only be nested > once, so if introduce a wrapper for c_p_m_rw(), we can avoid > recursive big lock, right? Don't we need that for other reasons? If not, we can drop it for now. -- error compiling committee.c: too many arguments to function
