Re: [Qemu-devel] [RFC PATCH v2 08/17] fuzz: Export the qemu_savevm_live_state function

["Dr. David Alan Gilbert" <dgilbert@redhat.com>]

* Oleinik, Alexander (alxndr@bu.edu) wrote:
> Skip the header when saving device state, as the header isn't handled by
> qemu_load_device_state
> 
> Signed-off-by: Alexander Oleinik <alxndr@bu.edu>
> ---
>  migration/savevm.c | 9 +++++++--
>  migration/savevm.h | 2 ++
>  2 files changed, 9 insertions(+), 2 deletions(-)
> 
> diff --git a/migration/savevm.c b/migration/savevm.c
> index 79ed44d475..5eac36e6ca 100644
> --- a/migration/savevm.c
> +++ b/migration/savevm.c
> @@ -1405,7 +1405,7 @@ void qemu_savevm_state_cleanup(void)
>      }
>  }
>  
> -static int qemu_savevm_state(QEMUFile *f, Error **errp)
> +int qemu_savevm_state(QEMUFile *f, Error **errp)
>  {
>      int ret;
>      MigrationState *ms = migrate_get_current();
> @@ -1471,11 +1471,16 @@ void qemu_savevm_live_state(QEMUFile *f)
>  int qemu_save_device_state(QEMUFile *f)
>  {
>      SaveStateEntry *se;
> -
> +    /*
> +     * qemu_load_device_state doesn't load the header. Either skip writing the
> +     * header or seek forward in the file, prior to loading device state
> +     */
> +#ifndef CONFIG_FUZZ
>      if (!migration_in_colo_state()) {
>          qemu_put_be32(f, QEMU_VM_FILE_MAGIC);
>          qemu_put_be32(f, QEMU_VM_FILE_VERSION);
>      }
> +#endif

I'd prefer if you just added a ', bool save_header' to the parameters
and then replace the '!migration_in_colo_state()' by 'save_header'

It's only called from two places at the moment,
'qmp_xen_save_devices_state' where I think it's always 'true'
and 'colo_do_checkpoint_transaction' where I think it's always false.

Dave

>      cpu_synchronize_all_states();
>  
>      QTAILQ_FOREACH(se, &savevm_state.handlers, entry) {
> diff --git a/migration/savevm.h b/migration/savevm.h
> index 51a4b9caa8..5405215cb4 100644
> --- a/migration/savevm.h
> +++ b/migration/savevm.h
> @@ -64,4 +64,6 @@ void qemu_loadvm_state_cleanup(void);
>  int qemu_loadvm_state_main(QEMUFile *f, MigrationIncomingState *mis);
>  int qemu_load_device_state(QEMUFile *f);
>  
> +int qemu_savevm_state(QEMUFile *f, Error **errp);
> +
>  #endif
> -- 
> 2.20.1
> 
--
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK