** Changed in: spice-vdagent (Ubuntu)
   Importance: Undecided => High

** Changed in: spice-vdagent (Ubuntu)
       Status: New => In Progress

** Changed in: spice-vdagent (Ubuntu)
     Assignee: (unassigned) => Jeremy Bícha (jbicha)

** Also affects: spice-vdagent (Ubuntu Resolute)
   Importance: Undecided
       Status: New

** Changed in: spice-vdagent (Ubuntu Resolute)
   Importance: Undecided => High

** Changed in: spice-vdagent (Ubuntu Resolute)
       Status: New => Triaged

** Changed in: spice-vdagent (Ubuntu Resolute)
     Assignee: (unassigned) => Jeremy Bícha (jbicha)

** Description changed:

- In an Ubuntu 26.04 guest running Cinnamon (X11 session) under QEMU/KVM
- with SPICE, the mouse pointer becomes misaligned after any change of
- screen resolution. This happens both when switching from the LightDM
- greeter to the user session (which use different resolutions) and when
- changing the resolution inside a running session.
+ Impact
+ ======
+ In an Ubuntu 26.04 guest running Cinnamon (X11 session) under QEMU/KVM with 
SPICE, the mouse pointer becomes misaligned after any change of screen 
resolution. This happens both when switching from the LightDM greeter to the 
user session (which use different resolutions) and when changing the resolution 
inside a running session.
  
  After the change, the pointer position the guest uses no longer matches
  the position of the host cursor. The offset grows toward the bottom-
  right of the screen, consistent with coordinates being scaled to the
  previous resolution.
  
+ Test Plan
+ =========
+ 
+ Where Problems Could Occur
+ =========================
+ 
+ Other Info
+ ==========
+ This issue was reported upstream as
+ https://gitlab.freedesktop.org/spice/linux/vd_agent/-/work_items/47
+ 
+ Workarounds
+ ===========
+ sudo systemctl restart spice-vdagentd immediately fixes the alignment until 
the next resolution change.
+ Restarting only the session agent (pkill -x spice-vdagent; spice-vdagent) 
also fixes it. This suggests the stale value lives in the agent, not the daemon.
+ 
+ Other Info from Original Bug Report
+ ===================================
  Environment
  
  Guest: Ubuntu 26.04, Cinnamon, X11 session (XDG_SESSION_TYPE=x11)
  spice-vdagent version: 0.23.0-1ubuntu0.1
  Host: QEMU/KVM, SPICE display, mouse mode client
  Video device: Virtio
  
  Steps to reproduce
- 
+ --------
  Log into a Cinnamon X11 session in a QEMU/KVM guest with SPICE and 
spice-vdagent running.
  Change the screen resolution, either from Display settings or by resizing the 
viewer window with auto-resize enabled.
  Move the mouse around the screen.
  
  Expected result
- 
+ ----------
  The guest pointer follows the host cursor exactly at the new resolution.
  
  Actual result
- 
- The guest pointer is scaled according to the previous resolution. xrandr
- reports the correct current screen size, but spice-vdagent keeps
- reporting the old one to spice-vdagentd.
+ ------------
+ The guest pointer is scaled according to the previous resolution. xrandr 
reports the correct current screen size, but spice-vdagent keeps reporting the 
old one to spice-vdagentd.
  
  Debug output (spice-vdagent -x -d, during a change from 1920x1200 to
  1874x1078):
  
  spice-vdagent: No guest output map, using output index as display id
  spice-vdagent: Sending guest screen resolutions to vdagentd:
  spice-vdagent:    display_id=0 - 1874x1078+0+0
  spice-vdagent: 0x651021003070 sent guest xorg resolution, arg1: 1920, arg2: 
1200, size 20
  
  The per-display geometry is correct (1874x1078), but the "guest xorg
  resolution" sent to vdagentd is still 1920x1200. At that moment, xrandr
  | head -1 reports current 1874 x 1078.
  
  (The "failed to call GetCurrentState from mutter over DBUS" messages
  also appear in the log. They are expected under Cinnamon, since
  org.gnome.Mutter.DisplayConfig does not exist there, and seem
  unrelated.)
  
- Workarounds
- 
- sudo systemctl restart spice-vdagentd immediately fixes the alignment until 
the next resolution change.
- Restarting only the session agent (pkill -x spice-vdagent; spice-vdagent) 
also fixes it. This suggests the stale value lives in the agent, not the daemon.
- 
  ProblemType: Bug
  DistroRelease: Ubuntu 26.04
  Package: spice-vdagent 0.23.0-1ubuntu0.1
  ProcVersionSignature: Ubuntu 7.0.0-34.34-generic 7.0.14
  Uname: Linux 7.0.0-34-generic x86_64
  ApportVersion: 2.34.1-0ubuntu0.1
  Architecture: amd64
  CasperMD5CheckResult: pass
  CurrentDesktop: X-Cinnamon
  Date: Wed Sep 30 09:42:22 2026
  InstallationDate: Installed on 2025-09-18 (377 days ago)
  InstallationMedia: Xubuntu 24.04.3 LTS "Noble Numbat" - Release amd64 
(20250805.1)
  ProcEnviron:
-  LANG=it_IT.UTF-8
-  PATH=(custom, no user)
-  SHELL=/bin/bash
-  TERM=xterm-256color
-  XDG_RUNTIME_DIR=<set>
+  LANG=it_IT.UTF-8
+  PATH=(custom, no user)
+  SHELL=/bin/bash
+  TERM=xterm-256color
+  XDG_RUNTIME_DIR=<set>
  SourcePackage: spice-vdagent
  UpgradeStatus: Upgraded to resolute on 2026-09-24 (6 days ago)

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https://bugs.launchpad.net/bugs/2168964

Title:
  spice-vdagent keeps sending stale X screen size after resolution
  change, causing mouse misalignment

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