Lv_display_set_buffers hangs infinitely

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Description

I’m trying to port LVGL 8.3 to LVGL 9.2.2, but it seems my display driver initialization never gets past lv_display_set_buffers. See below for details.

What MCU/Processor/Board and compiler are you using?

I’m using a Raspberry Pi 3 with gcc.

What do you want to achieve?

I simply want my flush callback to be called, but right now it is not.

What have you tried so far?

I tried following the porting example here: lvgl/examples/porting/lv_port_disp_template.c at release/v9.2 · lvgl/lvgl · GitHub

Code to reproduce

A minimal example of my initialization function looks like this:

void lv_display_init(void)
{
    my_disp_init();

    printf("Creating LVGL display\n");
    lv_display_t *disp = lv_display_create(DISPLAY_WIDTH, DISPLAY_HEIGHT);
    print("Setting flush cb\n");
    lv_display_set_flush_cb(disp, lv_display_flush);

    LV_ATTRIBUTE_MEM_ALIGN
    printf("Aligning LVGL memory\n");
    static uint8_t buffer[DISPLAY_WIDTH * DISPLAY_HEIGHT];
    printf("Created buffer\n");
    lv_display_set_buffers(disp, buffer, NULL, DISPLAY_WIDTH * DISPLAY_HEIGHT, LV_DISPLAY_RENDER_MODE_DIRECT);
    printf("Set buffer\n"); // this line never prints
}

static void lv_display_flush(lv_display_t *display, const lv_area_t *area, uint8_t px_map)
{
    printf("Display flush called!\n"); // this never prints either
    /* custom driving code here */
    lv_disp_flush_read(display);
}

Any idea what is wrong with the above?

(No meaningful screenshots to share)