Issue with wayland kiosk?

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1

I am using the lvgl linux port on an imx8 connected to a mipi lcd. I am building in yocto, but I am not using the yocto recipe for lvgl. My project has lvgl in its source so it just compiles on it’s own and it is using the wayland kiosk shell.
It runs fine using SDL, but when trying to run wayland I get this:

WAYLAND_DEBUG=1 ./lvglsim -b WAYLAND
[4045517.918] {Default Queue}  -> wl_display#1.get_registry(new id wl_registry#2)
[4045518.539] {Default Queue} wl_registry#2.global(1, "wl_compositor", 5)
[4045518.584] {Default Queue}  -> wl_registry#2.bind(1, "wl_compositor", 1, new id [unknown]#3)
[4045518.611] {Default Queue} wl_registry#2.global(2, "wl_subcompositor", 1)
[4045518.633] {Default Queue} wl_registry#2.global(3, "wp_viewporter", 1)
[4045518.651] {Default Queue} wl_registry#2.global(4, "zxdg_output_manager_v1", 2)
[4045518.670] {Default Queue} wl_registry#2.global(5, "wp_presentation", 1)
[4045518.690] {Default Queue} wl_registry#2.global(6, "wp_single_pixel_buffer_manager_v1", 1)
[4045518.708] {Default Queue} wl_registry#2.global(7, "wp_tearing_control_manager_v1", 1)
[4045518.729] {Default Queue} wl_registry#2.global(8, "zwp_relative_pointer_manager_v1", 1)
[4045518.747] {Default Queue} wl_registry#2.global(9, "zwp_pointer_constraints_v1", 1)
[4045518.768] {Default Queue} wl_registry#2.global(10, "zwp_input_timestamps_manager_v1", 1)
[4045518.786] {Default Queue} wl_registry#2.global(11, "weston_capture_v1", 1)
[4045518.805] {Default Queue} wl_registry#2.global(12, "wl_data_device_manager", 3)
[4045518.825] {Default Queue} wl_registry#2.global(13, "wl_shm", 2)
[4045518.844] {Default Queue}  -> wl_registry#2.bind(13, "wl_shm", 1, new id [unknown]#4)
[4045518.866] {Default Queue}  -> wl_registry#2.bind(13, "wl_shm", 1, new id [unknown]#5)
[4045518.887] {Default Queue} wl_registry#2.global(14, "weston_touch_calibration", 1)
[4045518.910] {Default Queue} wl_registry#2.global(15, "wl_viv", 1)
[4045518.928] {Default Queue} wl_registry#2.global(16, "wl_drm", 2)
[4045518.949] {Default Queue} wl_registry#2.global(17, "zwp_linux_dmabuf_v1", 5)
[4045518.968] {Default Queue} wl_registry#2.global(18, "wl_seat", 7)
[4045518.987] {Default Queue}  -> wl_registry#2.bind(18, "wl_seat", 1, new id [unknown]#6)
[4045519.009] {Default Queue} wl_registry#2.global(19, "weston_direct_display_v1", 1)
[4045519.034] {Default Queue} wl_registry#2.global(20, "zwp_linux_explicit_synchronization_v1", 2)
[4045519.054] {Default Queue} wl_registry#2.global(21, "weston_content_protection", 1)
[4045519.076] {Default Queue} wl_registry#2.global(22, "zwp_hdr10_metadata_v1", 1)
[4045519.098] {Default Queue} wl_registry#2.global(23, "wl_output", 4)
[4045519.119] {Default Queue}  -> wl_registry#2.bind(23, "wl_output", 1, new id [unknown]#7)
[4045519.143] {Default Queue} wl_registry#2.global(24, "xdg_wm_base", 5)
[4045519.167] {Default Queue}  -> wl_registry#2.bind(24, "xdg_wm_base", 2, new id [unknown]#8)
[4045519.197] {Default Queue}  -> wl_display#1.sync(new id wl_callback#9)
[4045519.846] {Display Queue} wl_display#1.delete_id(9)
[4045519.897] {Default Queue} discarded wl_shm#4.format(0)
[4045519.916] {Default Queue} discarded wl_shm#4.format(1)
[4045519.929] {Default Queue} discarded wl_shm#4.format(875709016)
[4045519.943] {Default Queue} discarded wl_shm#4.format(875708993)
[4045519.956] {Default Queue} discarded wl_shm#4.format(875714642)
[4045519.969] {Default Queue} discarded wl_shm#4.format(875708754)
[4045519.983] {Default Queue} discarded wl_shm#4.format(875714626)
[4045519.996] {Default Queue} discarded wl_shm#4.format(875708738)
[4045520.010] {Default Queue} discarded wl_shm#4.format(875710290)
[4045520.023] {Default Queue} discarded wl_shm#4.format(875710274)
[4045520.036] {Default Queue} discarded wl_shm#4.format(909199186)
[4045520.050] {Default Queue} discarded wl_shm#4.format(842093913)
[4045520.063] {Default Queue} discarded wl_shm#4.format(842094158)
[4045520.077] {Default Queue} discarded wl_shm#4.format(909203022)
[4045520.091] {Default Queue} discarded wl_shm#4.format(875714126)
[4045520.104] {Default Queue} discarded wl_shm#4.format(1448695129)
[4045520.117] {Default Queue} discarded wl_shm#4.format(1448434008)
[4045520.131] {Default Queue} discarded wl_shm#4.format(875708993)
[4045520.144] {Default Queue} discarded wl_shm#4.format(808665665)
[4045520.158] {Default Queue} discarded wl_shm#4.format(808665688)
[4045520.172] {Default Queue} discarded wl_shm#5.format(0)
[4045520.185] {Default Queue} discarded wl_shm#5.format(1)
[4045520.199] {Default Queue} discarded wl_shm#5.format(875709016)
[4045520.212] {Default Queue} discarded wl_shm#5.format(875708993)
[4045520.232] {Default Queue} discarded wl_shm#5.format(875714642)
[4045520.251] {Default Queue} discarded wl_shm#5.format(875708754)
[4045520.265] {Default Queue} discarded wl_shm#5.format(875714626)
[4045520.279] {Default Queue} discarded wl_shm#5.format(875708738)
[4045520.292] {Default Queue} discarded wl_shm#5.format(875710290)
[4045520.305] {Default Queue} discarded wl_shm#5.format(875710274)
[4045520.319] {Default Queue} discarded wl_shm#5.format(909199186)
[4045520.332] {Default Queue} discarded wl_shm#5.format(842093913)
[4045520.346] {Default Queue} discarded wl_shm#5.format(842094158)
[4045520.359] {Default Queue} discarded wl_shm#5.format(909203022)
[4045520.373] {Default Queue} discarded wl_shm#5.format(875714126)
[4045520.418] {Default Queue} discarded wl_shm#5.format(1448695129)
[4045520.433] {Default Queue} discarded wl_shm#5.format(1448434008)
[4045520.446] {Default Queue} discarded wl_shm#5.format(875708993)
[4045520.459] {Default Queue} discarded wl_shm#5.format(808665665)
[4045520.473] {Default Queue} discarded wl_shm#5.format(808665688)
[4045520.487] {Default Queue} wl_seat#6.capabilities(2)
[4045520.506] {Default Queue}  -> wl_seat#6.get_keyboard(new id wl_keyboard#10)
[4045520.667] {Default Queue} wl_output#7.geometry(0, 0, 34, 171, 0, "unknown", "unknown", 1)
[4045520.705] {Default Queue} wl_output#7.mode(3, 600, 1424, 74432)
[4045520.727] {Default Queue} wl_callback#9.done(9)
[4045521.098] {Default Queue}  -> wl_compositor#3.create_surface(new id wl_surface#9)
[4045521.125] {Default Queue}  -> xdg_wm_base#8.get_xdg_surface(new id xdg_surface#11, wl_surface#9)
[4045521.150] {Default Queue}  -> xdg_surface#11.get_toplevel(new id xdg_toplevel#12)
[4045521.169] {Default Queue}  -> xdg_toplevel#12.set_title("LVGL Simulator")
[4045521.186] {Default Queue}  -> xdg_toplevel#12.set_app_id("LVGL Simulator")
[4045521.396] {Default Queue}  -> wl_shm#5.create_pool(new id wl_shm_pool#13, fd 5, 6835200)
[4045521.425] {Default Queue}  -> wl_shm_pool#13.create_buffer(new id wl_buffer#14, 0, 1424, 600, 5696, 1)
[4045521.450] {Default Queue}  -> wl_shm_pool#13.create_buffer(new id wl_buffer#15, 3417600, 1424, 600, 5696, 1)
[4045521.479] {Default Queue}  -> wl_surface#9.commit()
[4045521.499] {Default Queue}  -> wl_display#1.sync(new id wl_callback#16)
[4045522.585] {Display Queue} wl_display#1.delete_id(16)
[4045522.634] {Default Queue} wl_keyboard#10.keymap(1, fd 5, 65528)
[4045536.120] {Default Queue} wl_callback#16.done(9)
[4045536.195] {Default Queue} xdg_toplevel#12.configure(1424, 600, array[4])
[4045536.215] {Default Queue} xdg_surface#11.configure(10)
[4045536.244] {Default Queue}  -> xdg_surface#11.ack_configure(10)
[Error] (2728.719, +2728719)     lv_wayland_xdg_configure_surface: Asserted at expression: window->resize_event.pending (Failed to receive the xdg_surface configuration event) lv_wayland_xdg_shell.c:149
lvglsim: /usr/src/debug/rx16demo/1.0+git/lvgl/src/drivers/wayland/lv_wayland_xdg_shell.c:149: lv_wayland_xdg_configure_surface: Assertion `0' failed.
Aborted (core dumped)

I don’t know much about wayland so I consulted with AI on the issue and it narrowed it down to changing the assert in this function:

void lv_wayland_xdg_configure_surface(lv_wl_window_t * window)
{
    /* XDG surfaces need to be configured before a buffer can be attached.
     * An (XDG) surface commit (without an attached buffer) triggers this
     * configure event */
    wl_surface_commit(window->body);
    wl_display_roundtrip(lv_wl_ctx.wl_display);
    LV_ASSERT_MSG(window->resize_event.pending, "Failed to receive the xdg_surface configuration event");
}

// Changed to:
void lv_wayland_xdg_configure_surface(lv_wl_window_t * window)
{
    /* XDG surfaces need to be configured before a buffer can be attached.
     * An (XDG) surface commit (without an attached buffer) triggers this
     * configure event */
    wl_surface_commit(window->body);
    wl_display_roundtrip(lv_wl_ctx.wl_display);
    LV_ASSERT_MSG(window->xdg.configured, "Failed to receive the xdg_surface configuration event");
}

And sure enough it works now. I went back through git and saw that before a big rewrite of the wayland driver the assert checked a similar window->is_window_configured.
I need to know if I found a bug, edge case, or something else? Also, is this fix ok, or will it blow up on me at some point?

Thanks,
Michael

2

I don’t have this issue, but I run wayland on a raspberry pi with lvgl 9.4 there are a lot of changes in 9.5 for wayland. But this code is the same.

3

@mike105105, I strongly recommend opening an issue in the LVGL Open repo. If you found a bug or an abnormal behavior, please provide a reproduction and details.

Wayland docs

https://lvgl.io/docs/open/9.4/details/integration/embedded_linux/drivers/wayland.html

4

Normally I would have, but since I am not experienced in wayland I wasn’t sure if it was a “me” issue. That’s why I asked here first. If someone more experienced looks at this and says “yeah that’s a bug” I was going to report it.

Michael

5

No problem, @mike105105 .

I guess @AndreCostaaa has experience with Linux stuff. Could you help us to understand what should happen here?