On Mon, 15 Jun 2020 15:41:54 -0600 "Edmund F. Nadolski" <edmund.f.nadol...@gmail.com> wrote:
> Hi, > > I'm a noob to VFIO so hopefully this is not to lame a question. > > I'm looking to set up a Linux guest VM with a direct-assigned nvme ssd, > that I can control by a usermode driver with VFIO. I enable nested > virtualization in KVM and set up the iommu parameters on the command line: > > Host: > # dmesg | grep Command > [ 0.000000] Command line: BOOT_IMAGE=(hd0,msdos1)/vmlinuz-5.7.0_0611+ > root=UUID=<blah> ro resume=UUID=<blah> console=tty0 console=ttyS4,115200 > intel_iommu=on iommu=pt > # modprobe kvm_intel nested=1 > # ls /sys/kernel/iommu_groups > 0 1 10 11 12 13 14 15 16 17 18 19 2 3 4 5 6 7 8 9 > > > The direct assignment works and I can see the drive in the guest, but > vfio does not create any iommu groups: > > Guest: > # lspci | grep Non > 07:00.0 Non-Volatile memory controller: Samsung Electronics Co Ltd NVMe > SSD Controller SM981/PM981/PM983 > # dmesg | grep -i -e DMAR -e IOMMU > [ 0.000000] Command line: BOOT_IMAGE=(hd0,msdos1)/vmlinuz-5.7.0 > root=/dev/mapper/fedora_localhost--live-root ro > resume=/dev/mapper/fedora_localhost--live-swap > rd.lvm.lv=fedora_localhost-live/root > rd.lvm.lv=fedora_localhost-live/swap intel_iommu=on iommu=pt > [ 0.064051] Kernel command line: > BOOT_IMAGE=(hd0,msdos1)/vmlinuz-5.7.0 > root=/dev/mapper/fedora_localhost--live-root ro > resume=/dev/mapper/fedora_localhost--live-swap > rd.lvm.lv=fedora_localhost-live/root > rd.lvm.lv=fedora_localhost-live/swap intel_iommu=on iommu=pt > [ 0.064102] DMAR: IOMMU enabled > [ 0.383193] iommu: Default domain type: Passthrough (set via kernel > command line) > [ 1.467722] intel_iommu=on > # ls -la /sys/kernel/iommu_groups/ > total 0 > drwxr-xr-x. 2 root root 0 Jun 15 15:16 . > drwxr-xr-x. 15 root root 0 Jun 15 15:12 .. > # > > Clearly I'm missing something in my setup/config, but I'm not sure that > that could be. Can anyone please advise? There needs to be an intel-iommu device in the VM configuration or else the intel_iommu=on option to the guest kernel will only print that enabled line and does nothing more. https://wiki.qemu.org/Features/VT-d _______________________________________________ vfio-users mailing list vfio-users@redhat.com https://www.redhat.com/mailman/listinfo/vfio-users
