From 6a37e21ca4bd650568a42c820470bf710937627e Mon Sep 17 00:00:00 2001
From: Yixue Wang <yixue.wang@outlook.com>
Date: Wed, 28 Jan 2026 16:11:23 +0800
Subject: [PATCH] xwayland: wrong expecting_event

According to

https://wayland.app/protocols/wayland#wl_seat:event:capabilities

Compositor might send capabilities when its capabilities change.
Decrease expecting_event here without any check might cause a
negative expecting_count.

Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/2123>
(cherry picked from commit 6bf6a9bff293fc1b26024d27d444829c945d3f0e)
---
 hw/xwayland/xwayland-input.c | 6 +++++-
 hw/xwayland/xwayland-input.h | 1 +
 2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/hw/xwayland/xwayland-input.c b/hw/xwayland/xwayland-input.c
index 024c870bd..3854149cb 100644
--- a/hw/xwayland/xwayland-input.c
+++ b/hw/xwayland/xwayland-input.c
@@ -1924,7 +1924,10 @@ seat_handle_capabilities(void *data, struct wl_seat *seat,
         release_touch(xwl_seat);
     }
 
-    xwl_seat->xwl_screen->expecting_event--;
+    if (xwl_seat->caps_initialized == FALSE) {
+        xwl_seat->caps_initialized = TRUE;
+        xwl_seat->xwl_screen->expecting_event--;
+    }
 }
 
 static void
@@ -1975,6 +1978,7 @@ create_input_device(struct xwl_screen *xwl_screen, uint32_t id, uint32_t version
         wl_registry_bind(xwl_screen->registry, id,
                          &wl_seat_interface, min(version, seat_version));
     xwl_seat->id = id;
+    xwl_seat->caps_initialized = FALSE;
 
     xwl_cursor_init(&xwl_seat->cursor, xwl_seat->xwl_screen,
                     xwl_seat_update_cursor);
diff --git a/hw/xwayland/xwayland-input.h b/hw/xwayland/xwayland-input.h
index 02319e297..9a2a40d72 100644
--- a/hw/xwayland/xwayland-input.h
+++ b/hw/xwayland/xwayland-input.h
@@ -77,6 +77,7 @@ struct xwl_seat {
     uint32_t id;
     uint32_t pointer_enter_serial;
     uint8_t pointer_enter_count;
+    Bool caps_initialized;
     struct xorg_list link;
     CursorPtr x_cursor;
     OsTimerPtr x_cursor_timer;