Re: [PATCH 21/36] vl: initialize displays before preconfig loop

[Igor Mammedov <imammedo@redhat.com>]

On Mon, 23 Nov 2020 09:14:20 -0500
Paolo Bonzini <pbonzini@redhat.com> wrote:

> Displays should be available before the monitor starts, so that
> it is possible to use the graphical console to interact with
> the monitor itself.
> 
> This patch is quite ugly, but all this is temporary.  The double
> call to qemu_init_displays will go away as soon we can unify machine
> initialization between the preconfig and "normal" flows, and so will
> the preconfig_exit_requested variable (that is only preconfig_requested
> remains).
> 
> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Reviewed-by: Igor Mammedov <imammedo@redhat.com>

> ---
>  softmmu/vl.c | 57 +++++++++++++++++++++++++++++++++-------------------
>  1 file changed, 36 insertions(+), 21 deletions(-)
> 
> diff --git a/softmmu/vl.c b/softmmu/vl.c
> index 6c8a103178..073d7412ad 100644
> --- a/softmmu/vl.c
> +++ b/softmmu/vl.c
> @@ -137,6 +137,7 @@ static ram_addr_t maxram_size;
>  static uint64_t ram_slots;
>  static int display_remote;
>  static int snapshot;
> +static bool preconfig_requested;
>  static QemuPluginList plugin_list = QTAILQ_HEAD_INITIALIZER(plugin_list);
>  static BlockdevOptionsQueue bdo_queue = QSIMPLEQ_HEAD_INITIALIZER(bdo_queue);
>  static bool nographic = false;
> @@ -3211,12 +3212,12 @@ static void qemu_validate_options(void)
>            }
>      }
>  
> -    if (loadvm && !preconfig_exit_requested) {
> +    if (loadvm && preconfig_requested) {
>          error_report("'preconfig' and 'loadvm' options are "
>                       "mutually exclusive");
>          exit(EXIT_FAILURE);
>      }
> -    if (incoming && !preconfig_exit_requested) {
> +    if (incoming && preconfig_requested) {
>          error_report("'preconfig' and 'incoming' options are "
>                       "mutually exclusive");
>          exit(EXIT_FAILURE);
> @@ -3380,6 +3381,28 @@ static void qemu_init_subsystems(void)
>      socket_init();
>  }
>  
> +static void qemu_init_displays(void)
> +{
> +    DisplayState *ds;
> +
> +    /* init local displays */
> +    ds = init_displaystate();
> +    qemu_display_init(ds, &dpy);
> +
> +    /* must be after terminal init, SDL library changes signal handlers */
> +    os_setup_signal_handling();
> +
> +    /* init remote displays */
> +#ifdef CONFIG_VNC
> +    qemu_opts_foreach(qemu_find_opts("vnc"),
> +                      vnc_init_func, NULL, &error_fatal);
> +#endif
> +
> +    if (using_spice) {
> +        qemu_spice.display_init();
> +    }
> +}
> +
>  /*
>   * Called after leaving preconfig state.  From here on runstate is
>   * RUN_STATE_PRELAUNCH or RUN_STATE_INMIGRATE.
> @@ -3443,8 +3466,6 @@ static void qemu_create_cli_devices(void)
>  
>  static void qemu_machine_creation_done(void)
>  {
> -    DisplayState *ds;
> -
>      cpu_synchronize_all_post_init();
>  
>      /* Did we create any drives that we failed to create a device for? */
> @@ -3467,23 +3488,6 @@ static void qemu_machine_creation_done(void)
>          qemu_register_reset(restore_boot_order, g_strdup(boot_order));
>      }
>  
> -    /* init local displays */
> -    ds = init_displaystate();
> -    qemu_display_init(ds, &dpy);
> -
> -    /* must be after terminal init, SDL library changes signal handlers */
> -    os_setup_signal_handling();
> -
> -    /* init remote displays */
> -#ifdef CONFIG_VNC
> -    qemu_opts_foreach(qemu_find_opts("vnc"),
> -                      vnc_init_func, NULL, &error_fatal);
> -#endif
> -
> -    if (using_spice) {
> -        qemu_spice.display_init();
> -    }
> -
>      if (foreach_device_config(DEV_GDB, gdbserver_start) < 0) {
>          exit(1);
>      }
> @@ -4083,6 +4087,7 @@ void qemu_init(int argc, char **argv, char **envp)
>                  break;
>              case QEMU_OPTION_preconfig:
>                  preconfig_exit_requested = false;
> +                preconfig_requested = true;
>                  break;
>              case QEMU_OPTION_enable_kvm:
>                  olist = qemu_find_opts("machine");
> @@ -4506,11 +4511,21 @@ void qemu_init(int argc, char **argv, char **envp)
>      qemu_resolve_machine_memdev();
>      parse_numa_opts(current_machine);
>  
> +    if (preconfig_requested) {
> +        qemu_init_displays();
> +    }
> +
>      /* do monitor/qmp handling at preconfig state if requested */
>      qemu_main_loop();
>  
>      qemu_init_board();
> +
>      qemu_create_cli_devices();
> +
> +    /* initialize displays after all errors have been reported */
> +    if (!preconfig_requested) {
> +        qemu_init_displays();
> +    }
>      qemu_machine_creation_done();
>  
>      if (loadvm) {