Hi Cédric, >-----Original Message----- >From: Cédric Le Goater <[email protected]> >Subject: Re: [PATCH v6 0/9] vfio: relax the vIOMMU check > >Zhenzhong, > >On 12/18/25 07:26, Zhenzhong Duan wrote: >> Hi >> >> This series relax the vIOMMU check and allows live migration with vIOMMU >> without VFs using device dirty tracking. It's rewritten based on first 4 >> patches of [1] from Joao. >> >> Currently what block us is the lack of dirty bitmap query with iommufd >> before unmap. By adding that query and handle some corner case we can >> relax the check. >> >> Based on vfio-next branch: >> >> patch1-2: add dirty bitmap query with iommufd >> patch3: a ranaming cleanup >> patch4-5: unmap_bitmap optimization >> patch6-7: fixes to avoid losing dirty pages >> patch8: add a blocker if VM memory is really quite large for >unmap_bitmap >> patch9: relax vIOMMU check >> >> Qemu code can be found at [2], it's based on vfio-next + base nesting series. >> >> We tested VM live migration (running QAT workload in VM) with QAT device >> passthrough, below matrix configs with guest config 'iommu=pt' and >'iommu=nopt': >> 1.Scalable mode vIOMMU + IOMMUFD cdev mode >> 2.Scalable mode vIOMMU + legacy VFIO mode >> 3.legacy mode vIOMMU + IOMMUFD cdev mode >> 4.legacy mode vIOMMU + legacy VFIO mode >> >> The QAT workload is a user level app that utilizes VFIO to control QAT >device. > > >FYI, > >There is a conflict with : > > [PATCH v9 00/19] intel_iommu: Enable first stage translation for >passthrough device > >which one should come first ?
The order is as below following your suggestion at [1]: [PATCH v9 00/19] intel_iommu: Enable first stage translation for passthrough device [PATCH v6 0/9] vfio: relax the vIOMMU check [PATCH v9 0/4] Implement ERRATA_772415 quirk for VTD [1] https://lore.kernel.org/qemu-devel/[email protected]/ Thanks Zhenzhong
