> From: Alex Williamson <alex.williamson@xxxxxxxxxx> > Sent: Saturday, April 15, 2023 4:08 AM > On Tue, 11 Apr 2023 13:28:03 -0600 > Alex Williamson <alex.williamson@xxxxxxxxxx> wrote: > > > On Tue, 21 Feb 2023 18:22:31 -0800 > > Yi Liu <yi.l.liu@xxxxxxxxx> wrote: > > > > > as some vfio_device drivers require a kvm pointer to be set in their > > > open_device and kvm pointer is set to VFIO in GROUP_ADD path. > > > > > > Signed-off-by: Yi Liu <yi.l.liu@xxxxxxxxx> > > > --- > > > v2: > > > - Adopt Alex's suggestion > > > v1: https://lore.kernel.org/kvm/20230221034114.135386-1-yi.l.liu@xxxxxxxxx/ > > > --- > > > Documentation/virt/kvm/devices/vfio.rst | 7 +++++++ > > > 1 file changed, 7 insertions(+) > > > > > > diff --git a/Documentation/virt/kvm/devices/vfio.rst > b/Documentation/virt/kvm/devices/vfio.rst > > > index 2d20dc561069..79b6811bb4f3 100644 > > > --- a/Documentation/virt/kvm/devices/vfio.rst > > > +++ b/Documentation/virt/kvm/devices/vfio.rst > > > @@ -39,3 +39,10 @@ KVM_DEV_VFIO_GROUP attributes: > > > - @groupfd is a file descriptor for a VFIO group; > > > - @tablefd is a file descriptor for a TCE table allocated via > > > KVM_CREATE_SPAPR_TCE. > > > + > > > +:: > > > + > > > +The GROUP_ADD operation above should be invoked prior to accessing the > > > +device file descriptor via VFIO_GROUP_GET_DEVICE_FD in order to support > > > +drivers which require a kvm pointer to be set in their .open_device() > > > +callback. > > > > I updated the title and commit log so as not to further construe that > > documentation can impose a requirement, otherwise applied to vfio next > > branch for v6.4. Thanks, > > Dropped > > https://lore.kernel.org/all/20230413163336.7ce6ecec.alex.williamson@xxxxxxxxxx/ > > Please resubmit, resolving the warning and change the title since a > requirement of some drivers does not equate to a requirement of the > API. Thanks, Sorry for it. May just remove the "::". So a version as below. Please let me know it is ok, then I'll submit it. >From abfc87425aa2977c08511b648a194bcfb072dcb8 Mon Sep 17 00:00:00 2001 From: Yi Liu <yi.l.liu@xxxxxxxxx> Date: Thu, 16 Feb 2023 02:37:28 -0800 Subject: [PATCH] docs: kvm: vfio: Suggest KVM_DEV_VFIO_GROUP_ADD vs VFIO_GROUP_GET_DEVICE_FD ordering as some vfio_device's open_device op requires kvm pointer and kvm pointer set is part of GROUP_ADD. Signed-off-by: Yi Liu <yi.l.liu@xxxxxxxxx> --- Documentation/virt/kvm/devices/vfio.rst | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/Documentation/virt/kvm/devices/vfio.rst b/Documentation/virt/kvm/devices/vfio.rst index 2d20dc561069..79b6811bb4f3 100644 --- a/Documentation/virt/kvm/devices/vfio.rst +++ b/Documentation/virt/kvm/devices/vfio.rst @@ -39,3 +39,8 @@ KVM_DEV_VFIO_GROUP attributes: - @groupfd is a file descriptor for a VFIO group; - @tablefd is a file descriptor for a TCE table allocated via KVM_CREATE_SPAPR_TCE. + +The GROUP_ADD operation above should be invoked prior to accessing the +device file descriptor via VFIO_GROUP_GET_DEVICE_FD in order to support +drivers which require a kvm pointer to be set in their .open_device() +callback. -- 2.34.1
