diff --git a/sys/external/bsd/drm2/dist/drm/radeon/radeon_cs.c b/sys/external/bsd/drm2/dist/drm/radeon/radeon_cs.c
index 3d030afabfeb..69fd0b9e3c6b 100644
--- a/sys/external/bsd/drm2/dist/drm/radeon/radeon_cs.c
+++ b/sys/external/bsd/drm2/dist/drm/radeon/radeon_cs.c
@@ -672,6 +672,8 @@ static int radeon_cs_ib_fill(struct radeon_device *rdev, struct radeon_cs_parser
 	return 0;
 }
 
+DEFINE_WW_CLASS(radeon_lossage_class);
+
 int radeon_cs_ioctl(struct drm_device *dev, void *data, struct drm_file *filp)
 {
 	struct radeon_device *rdev = dev->dev_private;
@@ -692,6 +694,8 @@ int radeon_cs_ioctl(struct drm_device *dev, void *data, struct drm_file *filp)
 	}
 	/* initialize parser */
 	memset(&parser, 0, sizeof(struct radeon_cs_parser));
+	ww_acquire_init(&parser.ticket, &radeon_lossage_class);
+	ww_acquire_fini(&parser.ticket);
 	parser.filp = filp;
 	parser.rdev = rdev;
 	parser.dev = rdev->dev;
@@ -702,6 +706,9 @@ int radeon_cs_ioctl(struct drm_device *dev, void *data, struct drm_file *filp)
 		radeon_cs_parser_fini(&parser, r, false);
 		up_read(&rdev->exclusive_lock);
 		r = radeon_cs_handle_lockup(rdev, r);
+		KASSERT(parser.ticket.wwx_acquired == ~0U);
+		KASSERT(parser.ticket.wwx_owner == NULL);
+		KDASSERT(parser.ticket.wwx_magic == 0xe9e9e9e9e9e9e9e9);
 		return r;
 	}
 
@@ -716,6 +723,9 @@ int radeon_cs_ioctl(struct drm_device *dev, void *data, struct drm_file *filp)
 		radeon_cs_parser_fini(&parser, r, false);
 		up_read(&rdev->exclusive_lock);
 		r = radeon_cs_handle_lockup(rdev, r);
+		KASSERT(parser.ticket.wwx_acquired == ~0U);
+		KASSERT(parser.ticket.wwx_owner == NULL);
+		KDASSERT(parser.ticket.wwx_magic == 0xe9e9e9e9e9e9e9e9);
 		return r;
 	}
 
@@ -733,6 +743,9 @@ out:
 	radeon_cs_parser_fini(&parser, r, true);
 	up_read(&rdev->exclusive_lock);
 	r = radeon_cs_handle_lockup(rdev, r);
+	KASSERT(parser.ticket.wwx_acquired == ~0U);
+	KASSERT(parser.ticket.wwx_owner == NULL);
+	KDASSERT(parser.ticket.wwx_magic == 0xe9e9e9e9e9e9e9e9);
 	return r;
 }