From af904d23acc7980fbf3aedf173dc96af1dd580b9 Mon Sep 17 00:00:00 2001
From: Ivan Molodetskikh <yalterz@gmail.com>
Date: Sat, 27 Jul 2024 13:43:27 +0300
Subject: tty: Add check for vblank on idle

---
 src/backend/tty.rs | 10 ++++++++++
 1 file changed, 10 insertions(+)

(limited to 'src')

diff --git a/src/backend/tty.rs b/src/backend/tty.rs
index fa7d4b18..10becafe 100644
--- a/src/backend/tty.rs
+++ b/src/backend/tty.rs
@@ -1178,6 +1178,16 @@ impl Tty {
             return;
         };
 
+        // This happened for someone reconnecting 2 monitors with a KVM switch:
+        // https://github.com/YaLTeR/niri/issues/556
+        //
+        // Maybe the vblank didn't get cancelled or got reordered weirdly? Either way, we can avoid
+        // crashing here.
+        if matches!(output_state.redraw_state, RedrawState::Idle) {
+            error!("got vblank for an idle output {name}");
+            return;
+        }
+
         // Mark the last frame as submitted.
         match surface.compositor.frame_submitted() {
             Ok(Some((mut feedback, target_presentation_time))) => {
-- 
cgit