On Tue, 8 Nov 2022 14:37:21 +0100
Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> wrote:
> From: Jason Gunthorpe <jgg@xxxxxxxxxx>
>
> [ Upstream commit f423fa1bc9fe1978e6b9f54927411b62cb43eb04 ]
>
> When converting to directly create the vfio_device the mdev driver has to
> put a vfio_register_emulated_iommu_dev() in the probe() and a pairing
> vfio_unregister_group_dev() in the remove.
>
> This was missed for gvt, add it.
>
> Cc: stable@xxxxxxxxxxxxxxx
> Fixes: 978cf586ac35 ("drm/i915/gvt: convert to use vfio_register_emulated_iommu_dev")
> Reported-by: Alex Williamson <alex.williamson@xxxxxxxxxx>
> Signed-off-by: Jason Gunthorpe <jgg@xxxxxxxxxx>
> Reviewed-by: Kevin Tian <kevin.tian@xxxxxxxxx>
> Reviewed-by: Christoph Hellwig <hch@xxxxxx>
> Link: https://lore.kernel.org/r/0-v1-013609965fe8+9d-vfio_gvt_unregister_jgg@xxxxxxxxxx
> Signed-off-by: Alex Williamson <alex.williamson@xxxxxxxxxx>
> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
> ---
> drivers/gpu/drm/i915/gvt/kvmgt.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/drivers/gpu/drm/i915/gvt/kvmgt.c b/drivers/gpu/drm/i915/gvt/kvmgt.c
> index e3cd58946477..dacd57732dbe 100644
> --- a/drivers/gpu/drm/i915/gvt/kvmgt.c
> +++ b/drivers/gpu/drm/i915/gvt/kvmgt.c
> @@ -1595,6 +1595,7 @@ static void intel_vgpu_remove(struct mdev_device *mdev)
>
> if (WARN_ON_ONCE(vgpu->attached))
> return;
> + vfio_unregister_group_dev(&vgpu->vfio_device);
> intel_gvt_destroy_vgpu(vgpu);
> }
>
Nak, the v6.0 backport for this also needs to call
vfio_uninit_group_dev(). kvmgt had missed both calls, but at the time
of f423fa1bc9fe this latter missing call had already been replaced by
vfio_put_device() in a5ddd2a99a7a, where cb9ff3f3b84c had implemented a
device release function with this call. The correct backport should be:
diff --git a/drivers/gpu/drm/i915/gvt/kvmgt.c b/drivers/gpu/drm/i915/gvt/kvmgt.c
index e3cd58946477..2404d856f764 100644
--- a/drivers/gpu/drm/i915/gvt/kvmgt.c
+++ b/drivers/gpu/drm/i915/gvt/kvmgt.c
@@ -1595,6 +1595,8 @@ static void intel_vgpu_remove(struct mdev_device *mdev)
if (WARN_ON_ONCE(vgpu->attached))
return;
+ vfio_unregister_group_dev(&vgpu->vfio_device);
+ vfio_uninit_group_dev(&vgpu->vfio_device);
intel_gvt_destroy_vgpu(vgpu);
}
Kevin, Yi, please confirm. Thanks,
Alex
