diff options
| author | Zhi Wang <zhi.a.wang@intel.com> | 2017-03-30 01:48:39 +0800 |
|---|---|---|
| committer | Zhenyu Wang <zhenyuw@linux.intel.com> | 2017-03-30 13:37:53 +0800 |
| commit | b79c52aef3cdee903017c1e9834b53996d70010e (patch) | |
| tree | d17a828c431dc76a2b79dedfdaecfb41ccbf7aff /drivers/gpu/drm/i915/gvt/kvmgt.c | |
| parent | bc2d4b62db67f817b09c782219996630e9c2f5e2 (diff) | |
drm/i915/gvt: Activate/de-activate vGPU in mdev ops.
This patch introduces two functions for activating/de-activating vGPU in
mdev ops.
A racing condition was found between virtual vblank emulation and KVGMT
mdev release path. V-blank emulation will emulate and inject V-blank
interrupt for every active vGPU with holding gvt->lock, while in mdev
release path, it will directly release hypervisor handle without changing
vGPU status or taking gvt->lock, so a kernel oops is encountered when
vblank emulation is injecting a interrupt with a invalid hypervisor
handle. (Reported by Terrence)
To solve this problem, we factor out vGPU activation/de-activation from
vGPU creation/destruction path and let KVMGT mdev release ops de-activate
the vGPU before release hypervisor handle. Once a vGPU is de-activated,
GVT-g will not emulate v-blank for it or touch the hypervisor handle.
Fixes: 659643f ("drm/i915/gvt/kvmgt: add vfio/mdev support to KVMGT")
Signed-off-by: Zhi Wang <zhi.a.wang@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Diffstat (limited to 'drivers/gpu/drm/i915/gvt/kvmgt.c')
| -rw-r--r-- | drivers/gpu/drm/i915/gvt/kvmgt.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/drivers/gpu/drm/i915/gvt/kvmgt.c b/drivers/gpu/drm/i915/gvt/kvmgt.c index d641214578a7..9843d74056a8 100644 --- a/drivers/gpu/drm/i915/gvt/kvmgt.c +++ b/drivers/gpu/drm/i915/gvt/kvmgt.c @@ -544,6 +544,8 @@ static int intel_vgpu_open(struct mdev_device *mdev) if (ret) goto undo_group; + intel_gvt_ops->vgpu_activate(vgpu); + atomic_set(&vgpu->vdev.released, 0); return ret; @@ -569,6 +571,8 @@ static void __intel_vgpu_release(struct intel_vgpu *vgpu) if (atomic_cmpxchg(&vgpu->vdev.released, 0, 1)) return; + intel_gvt_ops->vgpu_deactivate(vgpu); + ret = vfio_unregister_notifier(mdev_dev(vgpu->vdev.mdev), VFIO_IOMMU_NOTIFY, &vgpu->vdev.iommu_notifier); WARN(ret, "vfio_unregister_notifier for iommu failed: %d\n", ret); |