[PATCH 2/2] drm/i915/gvt: Unconditionally put reference to KVM when detaching vGPU

From: Sean Christopherson
Date: Thu Nov 10 2022 - 19:22:42 EST


Always put the KVM reference when closing a vCPU device, as
intel_vgpu_open_device() succeeds if and only if the KVM pointer is
valid and a reference to KVM is acquired. And if that doesn't hold true,
the call to kvm_page_track_unregister_notifier() a few lines earlier is
doomed.

Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>
---
drivers/gpu/drm/i915/gvt/kvmgt.c | 5 ++---
1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/i915/gvt/kvmgt.c b/drivers/gpu/drm/i915/gvt/kvmgt.c
index e67d5267fde0..714221f9a131 100644
--- a/drivers/gpu/drm/i915/gvt/kvmgt.c
+++ b/drivers/gpu/drm/i915/gvt/kvmgt.c
@@ -714,15 +714,14 @@ static void intel_vgpu_close_device(struct vfio_device *vfio_dev)

kvm_page_track_unregister_notifier(vgpu->vfio_device.kvm,
&vgpu->track_node);
+ kvm_put_kvm(vgpu->vfio_device.kvm);
+
kvmgt_protect_table_destroy(vgpu);
gvt_cache_destroy(vgpu);

intel_vgpu_release_msi_eventfd_ctx(vgpu);

vgpu->attached = false;
-
- if (vgpu->vfio_device.kvm)
- kvm_put_kvm(vgpu->vfio_device.kvm);
}

static u64 intel_vgpu_get_bar_addr(struct intel_vgpu *vgpu, int bar)
--
2.38.1.431.g37b22c650d-goog