Re: [PATCH] accel: print an error message and exit if plugin not loaded

[Richard Henderson]

On 9/5/22 11:13, Claudio Fontana wrote:
> If module_load_one, module_load_file fail for any reason
> (permissions, plugin not installed, ...), we need to provide some notification
> to the user to understand that this is happening; otherwise the errors
> reported on initialization will make no sense to the user.
>
> Signed-off-by: Claudio Fontana <cfontana@suse.de>
> ---
>   accel/accel-softmmu.c | 10 ++++++++--
>   1 file changed, 8 insertions(+), 2 deletions(-)
>
> diff --git a/accel/accel-softmmu.c b/accel/accel-softmmu.c
> index 67276e4f52..807708ee86 100644
> --- a/accel/accel-softmmu.c
> +++ b/accel/accel-softmmu.c
> @@ -66,15 +66,21 @@ void accel_init_ops_interfaces(AccelClass *ac)
>   {
>       const char *ac_name;
>       char *ops_name;
> +    ObjectClass *oc;
>       AccelOpsClass *ops;
>   
>       ac_name = object_class_get_name(OBJECT_CLASS(ac));
>       g_assert(ac_name != NULL);
>   
>       ops_name = g_strdup_printf("%s" ACCEL_OPS_SUFFIX, ac_name);
> -    ops = ACCEL_OPS_CLASS(module_object_class_by_name(ops_name));
> +    oc = module_object_class_by_name(ops_name);
> +    if (!oc) {
> +        error_report("fatal: could not find module object of type \"%s\", "
> +                     "plugin might not be loaded correctly", ops_name);
> +        exit(EXIT_FAILURE);
> +    }

The change is correct, in that we certainly cannot continue without the 
accelerator loaded.

But I'm very disappointed that the module interface does not use Error, so you have no 
choice but to use an extremely vague message here.  I would much prefer to plumb down an 
error parameter so that here one could simply pass &error_fatal.


r~