Hi Shameer, Thanks for the reply!
On Thu, Sep 05, 2024 at 12:55:52PM +0000, Shameerali Kolothum Thodi wrote: > > The main takeaway from the discussion is to > > 1) Turn the vSMMU module into a pluggable one, like intel-iommu > > 2) Move the per-SMMU pxb bus and device auto-assign into libvirt > > > > Apart from the multi-vSMMU thing, there's basic nesting series: > > 0) Keep updating to the latest kernel uAPIs to support nesting > > By this you mean the old HWPT based nested-smmuv3 support? HWPT + vIOMMU. The for-viommu/virq branches that I shared in my kernel series have those changes. Invalidations is done via the vIOMMU infrastructure. > > > > I was trying to do all these three, but apparently too ambitious. > > The kernel side of work is still taking a lot of my bandwidth. So > > far I had almost-zero progress on task (1) and completely-zero on > > task (2). > > > > <-- Help Needed ---> > > So, I'm wondering if anyone(s) might have some extra bandwidth in > > the following months helping these two tasks, either of which can > > be a standalone project I think. > > > > For task (0), I think I can keep updating the uAPI part, although > > it'd need some help for reviews, which I was hoping to occur after > > Intel sends the QEMU nesting backend patches. Once we know how big > > the rework is going to be, we may need to borrow some help at that > > point once again.. > > I might have some bandwidth starting October and can take a look at > task 1 above. I haven't gone through the VIOMMU API model completely > yet and plan to do that soon. Thank you! That'd be helpful! The major effort I think is in the VIRT code also, where "-device nested-smmuv3" must tell the info to build Device Tree or IORT. The vIOMMU uAPI is not that complicated. That being said, I am trying to add some kernel documentation for nested translation, so hopefully this would be helpful in the near future. > Also I am planning to attend KVM forum, so if there are anyone interested > to have a chat on this, please let me know. Wish I could make it to that. I think we will need another Oct thread to get all of us aligned once again. Regards Nicolin
