add new system file

hc

2024-02-20 102a0743326a03cd1a1202ceda21e175b7d3575c

 kernel/drivers/video/fbdev/hyperv_fb.c
..
..
@@ -798,12 +798,18 @@
798
798
 static int hvfb_on_panic(struct notifier_block *nb,
799
799
 			 unsigned long e, void *p)
800
800
 {
801
+	struct hv_device *hdev;
801
802
 	struct hvfb_par *par;
802
803
 	struct fb_info *info;
803
804
 
804
805
 	par = container_of(nb, struct hvfb_par, hvfb_panic_nb);
805
-	par->synchronous_fb = true;
806
806
 	info = par->info;
807
+	hdev = device_to_hv_device(info->device);
808
+
809
+	if (hv_ringbuffer_spinlock_busy(hdev->channel))
810
+		return NOTIFY_DONE;
811
+
812
+	par->synchronous_fb = true;
807
813
 	if (par->need_docopy)
808
814
 		hvfb_docopy(par, 0, dio_fb_size);
809
815
 	synthvid_update(info, 0, 0, INT_MAX, INT_MAX);