[PATCH 5.4 103/135] drm/i915/gvt: more locking for ppgtt mm LRU list

[Greg Kroah-Hartman]

From: Igor Druzhinin <igor.druzhinin@xxxxxxxxxx>

commit 0e9d7bb293f3f9c3ee376b126141407efb265f31 upstream.

When the lock was introduced in commit 72aabfb862e40 ("drm/i915/gvt: Add mutual
lock for ppgtt mm LRU list") one place got lost.

Fixes: 72aabfb862e4 ("drm/i915/gvt: Add mutual lock for ppgtt mm LRU list")
Signed-off-by: Igor Druzhinin <igor.druzhinin@xxxxxxxxxx>
Reviewed-by: Zhenyu Wang <zhenyuw@xxxxxxxxxxxxxxx>
Signed-off-by: Zhenyu Wang <zhenyuw@xxxxxxxxxxxxxxx>
Link: http://patchwork.freedesktop.org/patch/msgid/1580742421-25194-1-git-send-email-igor.druzhinin@xxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/gpu/drm/i915/gvt/gtt.c |    4 ++++
 1 file changed, 4 insertions(+)

--- a/drivers/gpu/drm/i915/gvt/gtt.c
+++ b/drivers/gpu/drm/i915/gvt/gtt.c
@@ -1956,7 +1956,11 @@ void _intel_vgpu_mm_release(struct kref
 
 	if (mm->type == INTEL_GVT_MM_PPGTT) {
 		list_del(&mm->ppgtt_mm.list);
+
+		mutex_lock(&mm->vgpu->gvt->gtt.ppgtt_mm_lock);
 		list_del(&mm->ppgtt_mm.lru_list);
+		mutex_unlock(&mm->vgpu->gvt->gtt.ppgtt_mm_lock);
+
 		invalidate_ppgtt_mm(mm);
 	} else {
 		vfree(mm->ggtt_mm.virtual_ggtt);