On Thu, 2014-09-11 at 15:23 -0700, Christoffer Dall wrote: > On Thu, Sep 11, 2014 at 04:14:09PM -0600, Alex Williamson wrote: > > On Tue, 2014-09-09 at 08:31 +0100, Eric Auger wrote: > > > This RFC series aims at enabling KVM platform device passthrough. > > > It implements a VFIO platform device, derived from VFIO PCI device. > > > > > > The VFIO platform device uses the host VFIO platform driver which must > > > be bound to the assigned device prior to the QEMU system start. > > > > > > - the guest can directly access the device register space > > > - assigned device IRQs are transparently routed to the guest by > > > QEMU/KVM (3 methods currently are supported: user-level eventfd > > > handling, irqfd, forwarded IRQs) > > > - iommu is transparently programmed to prevent the device from > > > accessing physical pages outside of the guest address space > > > > > > This patch series is made of the following patch files: > > > > > > 1-7) Modifications to PCI code to prepare for VFIO platform device > > > 8) split of PCI specific code and generic code (move) > > > 9-11) creation of the VFIO calxeda xgmac platform device, without irqfd > > > support (MMIO direct access and IRQ assignment). > > > 12) fake injection test modality (to test multiple IRQ) > > > 13) addition of irqfd/virqfd support > > > 14-16) forwarded IRQ > > > > > > Dependency List: > > > > > > QEMU dependencies: > > > [1] [PATCH v2 0/9] Dynamic sysbus device allocation support, Alex Graf > > > http://lists.gnu.org/archive/html/qemu-ppc/2014-07/msg00047.html > > > [2] [RFC v3] machvirt dynamic sysbus device instantiation, Eric Auger > > > [3] [PATCH v2 0/2] actual checks of KVM_CAP_IRQFD and KVM_CAP_IRQFD_RESAMPLE, > > > Eric Auger > > > http://lists.nongnu.org/archive/html/qemu-devel/2014-09/msg00589.html > > > [4] [RFC] vfio: migration to trace points, Eric Auger > > > http://lists.nongnu.org/archive/html/qemu-devel/2014-09/msg00569.html > > > > > > Kernel Dependencies: > > > [5] [RFC Patch v6 0/20] VFIO support for platform devices, Antonios Motakis > > > https://www.mail-archive.com/kvm@xxxxxxxxxxxxxxx/msg103247.html > > > [6] [PATCH v3] ARM: KVM: add irqfd support, Eric Auger > > > https://lkml.org/lkml/2014/9/1/141 > > > [7] arm/arm64: KVM: Various VGIC cleanups and improvements, Christoffer Dall > > > http://comments.gmane.org/gmane.linux.ports.arm.kernel/340430 > > > [8] [RFC v2 0/9] KVM-VFIO IRQ forward control, Eric Auger > > > https://lkml.org/lkml/2014/9/1/344 > > > [9] [RFC PATCH 0/9] ARM: Forwarding physical interrupts to a guest VM, > > > Marc Zyngier > > > http://lwn.net/Articles/603514/ > > > > > > kernel pieces can be found at: > > > http://git.linaro.org/people/eric.auger/linux.git > > > (branch 3.17rc3_irqfd_forward_integ_v2) > > > QEMU pieces can be found at: > > > http://git.linaro.org/people/eric.auger/qemu.git (branch vfio_integ_v6) > > > > > > The patch series was tested on Calxeda Midway (ARMv7) where one xgmac > > > is assigned to KVM host while the second one is assigned to the guest. > > > Reworked PCI device is not tested. > > > > > > Wiki for Calxeda Midway setup: > > > https://wiki.linaro.org/LEG/Engineering/Virtualization/Platform_Device_Passthrough_on_Midway > > > > > > History: > > > > > > v5->v6: > > > - rebase on 2.1rc5 PCI code > > > - forwarded IRQ first integraton > > > > Why? Are there acceleration paths that you're concerned cannot be > > implemented or we do not already have a proof of concept for? The base > > kernel patch series you depend on is 3 months old yet this series > > continues to grow and add new dependencies. Please let's prioritize > > getting something upstream instead of adding more blockers to prevent > > that. Thanks, > > > I'm not exactly sure what this changelog line was referring to > (depending on Marc's forwarding IRQ patches?), but just want to add that > there are a number of dependencies for the GIC that need to go in as > well (should happen within a few weeks), but I think it's unlikely that > the IRQ forwarding stuff goes in for v3.18 at this point. > > It may make sense as you suggest to keep that part out of this patch set > and something merged sooner as opposed to later, but I'm too jet-lagged > to completely understand if that's going to be a horrible mess. The point is that we're on v6 of a patch series and its first non-RFC posting and we're rolling in a first pass at a QEMU implementation that depends on a contested kernel RFC, which depends on another stagnant kernel RFC. I'm fine with working on it in parallel, but give me some light at the end of the tunnel as a reviewer and maintainer that this code isn't going to live indefinitely on the mailing list. Do we really need those GIC patches do be able to have non-KVM accelerated VFIO platform device assignment? We certainly don't need IRQ forwarding. Thanks, Alex _______________________________________________ kvmarm mailing list kvmarm@xxxxxxxxxxxxxxxxxxxxx https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
