Re: [PATCH 00/60] ui: add standalone VNC server over D-Bus

["Daniel P. Berrangé" <berrange@redhat.com>]

On Tue, Mar 17, 2026 at 12:50:14PM +0400, Marc-André Lureau wrote:
> This series adds qemu-vnc, a standalone VNC server that connects to a
> running QEMU instance via the D-Bus display interface (org.qemu.Display1).
> This allows serving a VNC display as a separate process with an independent
> lifecycle and privilege domain, without requiring VNC support compiled into
> the QEMU system emulator itself.
> 
> The bulk of the series is preparatory refactoring:

A few of the patches in this series are addressing bugs such as the
leaks. Where practical those should probably be ordered at the very
start of the series such that they have minimal deps and could be
cherry-picked to stable.

> 
> - Clean up VNC code: merge init/open, fix leaks, simplify error handling
> - Extract and clean up VT100 emulation from console-vc into a reusable unit
> - Reorganize ui/ code: move DisplaySurface functions, vgafont, datadir
> and other pieces into their own files
> - Refactor console APIs: rename methods, simplify listener registration,
> return completion status from gfx_update
> - Extract common ui sources into a static library that can be linked by
> both the system emulator and the new standalone binary
> 
> The final patch adds contrib/qemu-vnc, built when both VNC and D-Bus
> display support are enabled.
> 
> Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
> ---
> Marc-André Lureau (60):
>       ui/vnc-jobs: fix VncRectEntry leak on job cleanup
>       ui/vnc-jobs: clear source tag
>       ui/vnc-jobs: remove needless buffer_reset() before end
>       ui/vnc: clarify intent using buffer_empty() function
>       ui/vnc-jobs: vnc_has_job_locked() argument cannot be NULL
>       ui/vnc-jobs: remove dead VncJobQueue.exit
>       ui/vnc-jobs: remove vnc_queue_clear()
>       ui/vnc-jobs: narrow taking the lock when pushing empty jobs
>       ui/vnc-jobs: drop redundant (and needless) qemu_thread_get_self()
>       ui/console-vc: fix off-by-one in CSI J 2 (clear entire screen)
>       ui/console-vc: add UTF-8 input decoding with CP437 rendering
>       ui/console-vc: ignore string-type escape sequences
>       ui/console-vc: fix comment shift-out/in comments
>       ui/console: dispatch get_label() through QOM virtual method
>       ui/console-vc: introduce QemuVT100
>       ui/console-vc: set vt100 associated pixman image
>       ui/console-vc: vga_putcharxy()->vt100_putcharxy()
>       ui/console-vc: make invalidate_xy() take vt100
>       ui/console-vc: make show_cursor() take vt100
>       ui/console-vc: decouple VT100 display updates via function pointer
>       ui/console-vc: console_refresh() -> vt100_refresh()
>       ui/console-vc: move cursor blinking logic into VT100 layer
>       ui/console-vc: console_scroll() -> vt100_scroll()
>       ui/console-vc: refactor text_console_resize() into vt100_set_image()
>       ui/console-vc: move vc_put_lf() to VT100 layer as vt100_put_lf()
>       ui/console-vc: unify the write path
>       ui/console-vc: move VT100 state machine and output FIFO into QemuVT100
>       ui/console-vc: extract vt100_input() from vc_chr_write()
>       ui/console-vc: extract vt100_keysym() from qemu_text_console_handle_keysym()
>       ui/console-vc: extract vt100_init() and vt100_fini()
>       ui/console: remove console_ch_t typedef and console_write_ch()
>       ui: avoid duplicating vgafont16 in each translation unit
>       ui/vgafont: add SPDX license header
>       ui: move FONT_WIDTH/HEIGHT to vgafont.h
>       ui/console-vc: move VT100 emulation into separate unit
>       util: move datadir.c from system/
>       ui: move DisplaySurface functions to display-surface.c
>       ui: make qemu_default_pixelformat() static inline
>       ui: make unregister_displaychangelistener() skip unregistered
>       ui: minor code simplification
>       system: make qemu_del_vm_change_state_handler accept NULL
>       ui/vnc: assert preconditions instead of silently returning
>       ui/vnc: simplify vnc_init_func error handling
>       ui/vnc: VncDisplay.id is not const
>       ui/vnc: fix vnc_display_init() leak on failure
>       ui/vnc: merge vnc_display_init() and vnc_display_open()
>       ui/vnc: report an error for duplicate display id
>       ui/vnc: defer listener registration until the console is known
>       ui/vnc: explicitly link with png
>       ui/vnc: add vnc-system unit, to allow different implementations
>       ui/console: remove qemu_console_is_visible()
>       ui/console: simplify registering display/console change listener
>       ui/console: return completion status from gfx_update callback
>       ui/console: rename public API to use consistent qemu_console_ prefix
>       ui/console: move console_handle_touch_event() to input
>       ui: extract common sources into a static library
>       tests: rename the dbus-daemon helper script
>       tests/qtest: fix dbus-vmstate-test compilation
>       tests/qtest: drop DBUS_VMSTATE_TEST_TMPDIR
>       contrib/qemu-vnc: add standalone VNC server over D-Bus
> 
>  MAINTAINERS                                      |    5 +
>  docs/conf.py                                     |    3 +
>  docs/interop/dbus-display.rst                    |    2 +
>  docs/interop/dbus-vnc.rst                        |   26 +
>  docs/interop/index.rst                           |    1 +
>  docs/meson.build                                 |    1 +
>  docs/tools/index.rst                             |    1 +
>  docs/tools/qemu-vnc.rst                          |  199 +
>  meson.build                                      |   17 +
>  contrib/qemu-vnc/qemu-vnc.h                      |   46 +
>  contrib/qemu-vnc/trace.h                         |    4 +
>  hw/display/qxl.h                                 |    2 +-
>  include/ui/console.h                             |  146 +-
>  include/ui/input.h                               |   15 +
>  include/ui/qemu-pixman.h                         |    8 +
>  include/ui/surface.h                             |    2 -
>  ui/console-priv.h                                |    8 -
>  ui/cp437.h                                       |   13 +
>  ui/keymaps.h                                     |    1 +
>  ui/vgafont.h                                     | 4618 +---------------------
>  ui/vnc.h                                         |    9 +-
>  ui/vt100.h                                       |   92 +
>  contrib/qemu-vnc/audio.c                         |  307 ++
>  contrib/qemu-vnc/chardev.c                       |  127 +
>  contrib/qemu-vnc/clipboard.c                     |  378 ++
>  contrib/qemu-vnc/console.c                       |  168 +
>  contrib/qemu-vnc/dbus.c                          |  439 ++
>  contrib/qemu-vnc/display.c                       |  456 +++
>  contrib/qemu-vnc/input.c                         |  239 ++
>  contrib/qemu-vnc/qemu-vnc.c                      |  450 +++
>  contrib/qemu-vnc/stubs.c                         |   66 +
>  contrib/qemu-vnc/utils.c                         |   59 +
>  hw/arm/musicpal.c                                |    7 +-
>  hw/display/artist.c                              |    8 +-
>  hw/display/ati.c                                 |   16 +-
>  hw/display/bcm2835_fb.c                          |   12 +-
>  hw/display/bochs-display.c                       |   20 +-
>  hw/display/cg3.c                                 |   11 +-
>  hw/display/cirrus_vga.c                          |    8 +-
>  hw/display/cirrus_vga_isa.c                      |    2 +-
>  hw/display/dm163.c                               |   10 +-
>  hw/display/exynos4210_fimd.c                     |   10 +-
>  hw/display/g364fb.c                              |   19 +-
>  hw/display/jazz_led.c                            |   24 +-
>  hw/display/macfb.c                               |   12 +-
>  hw/display/next-fb.c                             |    8 +-
>  hw/display/omap_lcdc.c                           |   18 +-
>  hw/display/pl110.c                               |    9 +-
>  hw/display/qxl-render.c                          |   18 +-
>  hw/display/qxl.c                                 |   25 +-
>  hw/display/ramfb-standalone.c                    |    6 +-
>  hw/display/ramfb.c                               |    4 +-
>  hw/display/sm501.c                               |   14 +-
>  hw/display/ssd0303.c                             |   14 +-
>  hw/display/ssd0323.c                             |   16 +-
>  hw/display/tcx.c                                 |   22 +-
>  hw/display/vga-isa.c                             |    2 +-
>  hw/display/vga-mmio.c                            |    2 +-
>  hw/display/vga-pci.c                             |    6 +-
>  hw/display/vga.c                                 |   60 +-
>  hw/display/vhost-user-gpu.c                      |   22 +-
>  hw/display/virtio-gpu-base.c                     |    7 +-
>  hw/display/virtio-gpu-rutabaga.c                 |   10 +-
>  hw/display/virtio-gpu-udmabuf.c                  |    4 +-
>  hw/display/virtio-gpu-virgl.c                    |   20 +-
>  hw/display/virtio-gpu.c                          |   26 +-
>  hw/display/virtio-vga.c                          |   10 +-
>  hw/display/vmware_vga.c                          |   21 +-
>  hw/display/xenfb.c                               |   12 +-
>  hw/display/xlnx_dp.c                             |   20 +-
>  hw/vfio/display.c                                |   49 +-
>  system/runstate.c                                |    3 +
>  tests/qtest/dbus-vmstate-test.c                  |   13 +-
>  tests/qtest/dbus-vnc-test.c                      |  733 ++++
>  ui/console-vc-stubs.c                            |    9 +-
>  ui/console-vc.c                                  | 1021 +----
>  ui/console.c                                     |  471 +--
>  ui/cp437.c                                       |  205 +
>  ui/curses.c                                      |   23 +-
>  ui/dbus-console.c                                |   16 +-
>  ui/dbus-listener.c                               |   37 +-
>  ui/display-surface.c                             |  107 +
>  ui/egl-headless.c                                |    8 +-
>  ui/gtk-egl.c                                     |    6 +-
>  ui/gtk-gl-area.c                                 |    6 +-
>  ui/gtk.c                                         |   36 +-
>  ui/input.c                                       |   65 +
>  ui/keymaps.c                                     |   13 +-
>  ui/sdl2-2d.c                                     |    2 +-
>  ui/sdl2-gl.c                                     |    2 +-
>  ui/sdl2.c                                        |   24 +-
>  ui/spice-display.c                               |   24 +-
>  ui/vgafont.c                                     | 4616 +++++++++++++++++++++
>  ui/vnc-jobs.c                                    |   54 +-
>  ui/vnc-system.c                                  |   19 +
>  ui/vnc.c                                         |  202 +-
>  ui/vt100.c                                       |  987 +++++
>  {system => util}/datadir.c                       |    0
>  contrib/qemu-vnc/meson.build                     |   26 +
>  contrib/qemu-vnc/qemu-vnc1.xml                   |  174 +
>  contrib/qemu-vnc/trace-events                    |   20 +
>  hw/display/apple-gfx.m                           |   26 +-
>  meson_options.txt                                |    2 +
>  scripts/meson-buildoptions.sh                    |    3 +
>  system/meson.build                               |    1 -
>  system/trace-events                              |    1 -
>  tests/{dbus-vmstate-daemon.sh => dbus-daemon.sh} |   16 +-
>  tests/qtest/meson.build                          |   13 +-
>  ui/cocoa.m                                       |   23 +-
>  ui/meson.build                                   |  103 +-
>  util/meson.build                                 |    1 +
>  util/trace-events                                |    3 +
>  112 files changed, 10982 insertions(+), 6624 deletions(-)
> ---
> base-commit: 559919ce54927d59b215a4665eda7ab6118a48aa
> change-id: 20260312-qemu-vnc-9662fc572262
> 
> Best regards,
> -- 
> Marc-André Lureau <marcandre.lureau@redhat.com>
> 
> 

With regards,
Daniel
-- 
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