Re: [PATCH] migration: vmsd errp handlers: return bool

[Peter Xu <peterx@redhat.com>]

On Mon, Oct 20, 2025 at 12:19:07PM +0300, Vladimir Sementsov-Ogievskiy wrote:
> @@ -255,13 +252,12 @@ int vmstate_load_state(QEMUFile *f, const VMStateDescription *vmsd,
>          qemu_file_set_error(f, ret);
>          return ret;
>      }
> -    if (vmsd->post_load_errp) {
> -        ret = vmsd->post_load_errp(opaque, version_id, errp);
> -        if (ret < 0) {
> -            error_prepend(errp, "post load hook failed for: %s, version_id: "
> -                          "%d, minimum_version: %d, ret: %d: ", vmsd->name,
> -                          vmsd->version_id, vmsd->minimum_version_id, ret);
> -        }
> +    if (vmsd->post_load_errp && !vmsd->post_load_errp(opaque, version_id,

I think this will change the semantics even if I do not expect a real user
to exist.. if post_load_errp() returned true here, then it'll keep looking
for post_load() and execute.

It might still be good to keep the old semantics, so that if
post_load_errp() is provided, then we ignore post_load().  Same to the rest
hooks.

> +                                                      errp)) {
> +        error_prepend(errp, "post load hook failed for: %s, version_id: "
> +                      "%d, minimum_version: %d, ret: %d: ", vmsd->name,
> +                      vmsd->version_id, vmsd->minimum_version_id, ret);
> +        ret = -EINVAL;
>      } else if (vmsd->post_load) {
>          ret = vmsd->post_load(opaque, version_id);
>          if (ret < 0) {
> @@ -438,9 +434,8 @@ int vmstate_save_state_v(QEMUFile *f, const VMStateDescription *vmsd,
>      trace_vmstate_save_state_top(vmsd->name);
>  
>      if (vmsd->pre_save_errp) {
> -        ret = vmsd->pre_save_errp(opaque, errp);
>          trace_vmstate_save_state_pre_save_res(vmsd->name, ret);
> -        if (ret < 0) {
> +        if (!vmsd->pre_save_errp(opaque, errp)) {
>              error_prepend(errp, "pre-save for %s failed, ret: %d: ",
>                            vmsd->name, ret);
>          }
> -- 
> 2.48.1
> 

-- 
Peter Xu