On Mon, Aug 11, 2014 at 03:04:57PM +0800, Le Tan wrote: > Hi, > > These patches are intended to introduce Intel IOMMU (VT-d) emulation to q35 > chipset. The major job in these patches is to add support for emulating Intel > IOMMU according to the VT-d specification, including basic responses to CSRs > accesses, the logics of DMAR (DMA remapping) and DMA memory address > translations.
Thanks! Looks very good overall, I noted some coding style issues - I didn't bother reporting each issue in every place where it appears - reported each issue once only, so please find and fix all instances of each issue. > Features implemented for now are: > 1. Response to important CSRs accesses; > 2. DMAR (DMA remapping) without PASID support; > 3. Primary fault logging; > 4. Support both register-based and queued invalidation for IOTLB and context > cache invalidation; > 5. Add DMAR table to ACPI tables to expose VT-d to BIOS; > 6. Add "-machine iommu=on|off" option to enable/disable VT-d; > 7. Only one DMAR unit for all the devices of PCI Segment 0. > > Testing: > 1. L1 guest with Linux with intel_iommu=on can interact with VT-d and boot > smoothly, and there exists information about VT-d in the log of kernel; > 2. Run L1 with VT-d, L2 guest with Linux can boot smoothly withou PCI device > passthrough; > 3. Run L1 with VT-d and "-soundhw ac97 (QEMU_AUDIO_DRV=alsa)", then assign the > sound card to L2; L2 can boot smoothly with legacy PCI assignment and I can > hear the music played in L2 from the host speakers; > 4. Jailhouse hypervisor can run smoothly(tested by Jan). > 5. Run L1 with VT-d and e1000 network card, then assign e1000 to L2; L2 will > be > STUCK when booting. This still remains unsolved now. As far as I know, I > suppose > that the L2 crashes when doing e1000_probe(). The QEMU of L1 will dump > something with "KVM: entry failed, hardware error 0x0", and the KVM of host > will print "nested_vmx_exit_handled failed vm entry 7". Unlike assigning the > sound card, after being assigned to L2, there is no translation entry of e1000 > through VT-d, which I think means that e1000 doesn't issue any DMA access > during > the boot of L2. Sometimes the kernel of L2 will print "divide error" during > booting. Maybe it results from the lack of reset mechanism. > 6. VFIO is tested and is similar to legacy pci assignment. > > Discussion: > 1. There is one functionality called Zero-Length-Read (ZLR) which supports > zero > length DMA read requests to write-only pages. If the VT-d emulation supports > ZLR, we need to know the exact length of one access. For now can QEMU express > zero-length requests? > > TODO: > 1. Context cache and IOTLB cache; > 2. Fix the bug of legacy PCI assignment; > > Changes since v2: > *address reviewing suggestions given by Jan > -add support for primary fault logging > -add support for queued invalidation > > Changes since v1: > *address reviewing suggestions given by Michael, Paolo, Stefan and Jan > -split intel_iommu.h to include/hw/i386/intel_iommu.h and > hw/i386/intel_iommu_internal.h > -change the copyright information > -change D() to VTD_DPRINTF() > -remove dead code > -rename constant definitions with consistent prefix VTD_ > -rename some struct definitions according to QEMU standard > -rename some CSRs access functions > -use endian-save functions to access CSRs > -change machine option to "iommu=on|off" > > Thanks very much! > > Git trees: > https://github.com/tamlok/qemu > > Le Tan (5): > iommu: add is_write as a parameter to the translate function of > MemoryRegionIOMMUOps > intel-iommu: introduce Intel IOMMU (VT-d) emulation > intel-iommu: add DMAR table to ACPI tables > intel-iommu: add Intel IOMMU emulation to q35 and add a machine option > "iommu" as a switch > intel-iommu: add supports for queued invalidation interface > > exec.c | 2 +- > hw/alpha/typhoon.c | 3 +- > hw/core/machine.c | 27 +- > hw/i386/Makefile.objs | 1 + > hw/i386/acpi-build.c | 41 + > hw/i386/acpi-defs.h | 70 ++ > hw/i386/intel_iommu.c | 1722 > ++++++++++++++++++++++++++++++++++++++++ > hw/i386/intel_iommu_internal.h | 358 +++++++++ > hw/pci-host/apb.c | 3 +- > hw/pci-host/q35.c | 64 +- > hw/ppc/spapr_iommu.c | 3 +- > include/exec/memory.h | 2 +- > include/hw/boards.h | 1 + > include/hw/i386/intel_iommu.h | 90 +++ > include/hw/pci-host/q35.h | 2 + > qemu-options.hx | 5 +- > vl.c | 4 + > 17 files changed, 2384 insertions(+), 14 deletions(-) > create mode 100644 hw/i386/intel_iommu.c > create mode 100644 hw/i386/intel_iommu_internal.h > create mode 100644 include/hw/i386/intel_iommu.h > > -- > 1.9.1
