Hi everyone. I got it working, now I am learning/reading how things fit/work :) For other newbies's benefit, here is what was required : a) On the host machine, ensured that virtualization is supported via hardware/CPU/chipset. b) If a) is applicable, then, on the host machine, enabled IOMMU in the kernel (via kernel command-line argument intel_iommu=on), and then booted the host machine with this kernel. c) Then, attached a pci-device on to a KVM guest machine. d) After the guest machine finished booting, *lspci* showed the device both on the host, as well as the guest. Thanks and Regards, Ajay On Tue, Sep 28, 2021 at 8:24 PM Ajay Garg <ajaygargnsit@xxxxxxxxx> wrote: > > Hi All. > > I made some progress, but still pci-passthrough is not enabled. > > > Following are the bullet-points : > > a) > On host, /proc/cpuinfo shows the following : > > ######################################## > ajay@ajay-Latitude-E6320:~$ cat /proc/cpuinfo | grep vmx | wc -l > 4 > ######################################## > > > b) > On guest, /proc/cpuinfo shows the following : > > ######################################## > ajay@ajay-Standard-PC-i440FX-PIIX-1996:~$ cat /proc/cpuinfo | grep vmx | wc -l > 0 > ######################################## > > > > c) > Guest has been booted with intel_iommu on, as confirmed by the following logs : > > ######################################## > Sep 28 20:05:46 ajay-Standard-PC-i440FX-PIIX-1996 kernel: [ > 0.025210] Kernel command line: > BOOT_IMAGE=/boot/vmlinuz-5.11.0-37-generic > root=UUID=a32e7e30-7796-464b-9efc-720eb4fc7706 ro quiet splash > intel_iommu=on vt.handoff=7 > Sep 28 20:05:46 ajay-Standard-PC-i440FX-PIIX-1996 kernel: [ > 0.025301] DMAR: IOMMU enabled > ######################################## > > > Note that just one DMAR log is seen. > > > d) > On guest, following are the outputs, when trying to observe virtual > iommu devices/groups etc : > > ######################################## > ajay@ajay-Standard-PC-i440FX-PIIX-1996:~$ ls -lrth /sys/kernel/iommu_groups/ > total 0 > > ajay@ajay-Standard-PC-i440FX-PIIX-1996:~$ ls -lrth /sys/devices/virtual/iommu > ls: cannot access '/sys/devices/virtual/iommu': No such file or directory > ######################################## > > > What am I missing? > > > > > On Tue, Sep 28, 2021 at 1:03 PM Ajay Garg <ajaygargnsit@xxxxxxxxx> wrote: > > > > Hi All. > > > > I have the following set up: > > > > * Host : Ubuntu-16, on a amd64 hardware > > * Guest : Ubuntu-21, as a VM on QEMU/KVM. > > > > > > Now, I have a SD-MMC card-reader attached physically on the host, > > which is listed as expected if I do lspci on the host : > > > > ############################################ > > ajay@ajay-Latitude-E6320:~/ldd3$ lspci > > .... > > .... > > 0a:00.0 SD Host controller: O2 Micro, Inc. OZ600FJ0/OZ900FJ0/OZ600FJS > > SD/MMC Card Reader Controller (rev 05) > > .... > > ############################################ > > > > > > However, if I try doing lspci on the guest, this pci-device is not listed. > > > > > > > > > > So, I have the following queries : > > > > * Would it require enabling pci-passthrough (if not already) in the > > guest-kernel, on a global basis? > > * Does having raw-physical-access on the guest, require support from > > the pci-device itself? > > > > > > My ultimate aim is to get the sd-mmc-driver that I wrote for the > > host-machine, to run unmodified on the guest-machine (obviously after > > the sd-card-reader is detected on the guest, and the code recompiled > > on the guest). > > > > > > Will be grateful for any pointers. > > > > > > Thanks and Regards, > > Ajay
