On Fri, Feb 22, 2019 at 09:31:56PM +0200, Jarkko Sakkinen wrote: > On Fri, Feb 22, 2019 at 10:23:02AM -0500, Michael S. Tsirkin wrote: > > On Fri, Feb 22, 2019 at 12:26:10PM +0200, Jarkko Sakkinen wrote: > > > On Thu, Feb 21, 2019 at 06:14:02PM -0800, David Tolnay wrote: > > > > Add a config TCG_VIRTIO_VTPM which enables a driver providing the guest > > > > kernel side of TPM over virtio. > > > > > > > > Use case: TPM support is needed for performing trusted work from within > > > > a virtual machine launched by Chrome OS. > > > > > > > > Tested inside crosvm, the Chrome OS virtual machine monitor. Crosvm's > > > > implementation of the virtio TPM device can be found in these two source > > > > files: > > > > > > > > - https://chromium.googlesource.com/chromiumos/platform/crosvm/+/18ce5713e6cb99c40aafec52b67c28ba12a44f31/devices/src/virtio/tpm.rs > > > > - https://chromium.googlesource.com/chromiumos/platform/crosvm/+/18ce5713e6cb99c40aafec52b67c28ba12a44f31/tpm2/src/lib.rs > > > > > > These files/links do not make sense for kernel testing. Please remove > > > them from the next version. > > > > To clarify generally for a virtio device we want > > - guest support > > - device support > > - spec > > > > If the device is implemented in qemu and guest in linux kernel, > > then there are lots of people familiar with these > > programming environments, so sometimes we merge > > guest and host code even if spec isn't written up at all. > > > > If you don't want to do that there's a small number of people who can > > properly review code, e.g. I don't think lots of people on this list are > > familiar with crosvm. One way to address this would be to build a QEMU > > implementation. Another would be to write up a spec. You can do both > > too :) > > I don't really understand your arguments. > > /Jarkko Jarkko, I am not making any argument at all. I am trying to suggest ways for this driver to get upstream. And I am saying that while I agree availability of an implementation in crosvm isn't sufficient, availability of a software device implementation in QEMU is not an absolute prerequisite for including a virtio driver in Linux. If there's a virtio spec explaining how to write one, that can be enough. -- MST
