On Fri, Mar 31, 2017 at 03:36:28PM +0800, Peter Xu wrote: > At the very beginning, the x86 vIOMMUs are created via "-M iommu=on". > We moved one step further a year ago to have the vIOMMUs just like a > general device, so that we can init them with far more specific > parameters with "-device" interface. > > However, gradually we found that problem starts to occur due to this. > The main issue is that the DMA address space of any PCI device is > postponed to be init after device realization, while some devices' > realizations would depend on this address space. That looks like a > dead lock. We have patches and solutions for different single problem, > but, maybe it's time we can consider to solve the root cause this > time, of course after 2.9 release. > > This series tries to solve the root cause, and move vIOMMU inits back > to machine init for x86 platforms. Then, we'll have solid DMA address > space for each device even during realization. > > Please kindly review. Thanks.
I think it's a clean way to do it at a high level. However I would like to set a tag in the class rather than listing specific devices. Also, init order should be consistent for all machines not just q35. > Peter Xu (5): > QemuOpts: introduce qemu_opts_extract() > util: export device_init_func() > util: propagate error for device_func_init() > q35: init vIOMMU during machine init > pci: move dma_as init back to bus realize > > hw/pci-host/q35.c | 45 +++++++++++++++++++++++++++++++++++++++++++++ > hw/pci/pci.c | 21 +-------------------- > include/hw/pci/pci_bus.h | 2 -- > include/qemu-common.h | 1 + > include/qemu/option.h | 2 ++ > include/sysemu/sysemu.h | 1 - > util/qemu-option.c | 24 ++++++++++++++++++++++++ > vl.c | 9 ++------- > 8 files changed, 75 insertions(+), 30 deletions(-) > > -- > 2.7.4
