Re: [Qemu-devel] [PATCH v1 1/5] machine: Add a valid_cpu_types property

[Alistair Francis]

On Tue, Oct 3, 2017 at 1:23 PM, Eduardo Habkost <address@hidden> wrote:
> On Tue, Oct 03, 2017 at 01:05:09PM -0700, Alistair Francis wrote:
>> This patch add a MachineClass element that can be set in the machine C
>> code to specify a list of supported CPU types. If the supported CPU
>> types are specified the user enter CPU (by -cpu at runtime) is checked
>> against the supported types and QEMU exits if they aren't supported.
>>
>> Signed-off-by: Alistair Francis <address@hidden>
>> ---
>
> Thanks!
>
> Reviewed-by: Eduardo Habkost <address@hidden>
>
> However, I will squash the following changes before queueing,
> because:
>
> * object_class_dynamic_cast() is safe even if class is NULL,
>   so there's no need to validate cpu_type here.
> * "must not be valid" sounds like the CPU is not allowed to be a
>   valid CPU, so I rewrote the comment.
>
>
> diff --git a/hw/core/machine.c b/hw/core/machine.c
> index 3afc6a7b5b..36c2fb069c 100644
> --- a/hw/core/machine.c
> +++ b/hw/core/machine.c
> @@ -766,9 +766,6 @@ void machine_run_board_init(MachineState *machine)
>          ObjectClass *class = object_class_by_name(machine->cpu_type);
>          int i;
>
> -        /* machine->cpu_type is supposed to be always a valid QOM type */
> -        assert(class);
> -
>          for (i = 0; machine_class->valid_cpu_types[i]; i++) {
>              if (object_class_dynamic_cast(class,
>                                            
> machine_class->valid_cpu_types[i])) {
> @@ -780,7 +777,7 @@ void machine_run_board_init(MachineState *machine)
>          }
>
>          if (!machine_class->valid_cpu_types[i]) {
> -            /* The user specified CPU must not be a valid CPU */
> +            /* The user specified CPU is not valid */
>              error_report("Invalid CPU type: %s", machine->cpu_type);
>              error_printf("The valid types are: %s",
>                           machine_class->valid_cpu_types[0]);

Looks good to me.

Does that mean you are taking the whole series now?

Thanks,
Alistair

>>
>> V1:
>>  - Use 'type' in the error message
>>  - Move a uneeded operation out of the for loop
>>  - Remove the goto
>> RFC v2:
>>  - Rebase on Igor's cpu_type work
>>  - Use object_class_dynamic_cast()
>>  - Use a NULL terminated cahr** list
>>  - Do the check before the machine_class init() is called
>>
>>
>>  hw/core/machine.c   | 35 +++++++++++++++++++++++++++++++++++
>>  include/hw/boards.h |  1 +
>>  2 files changed, 36 insertions(+)
>>
>> diff --git a/hw/core/machine.c b/hw/core/machine.c
>> index 80647edc2a..3afc6a7b5b 100644
>> --- a/hw/core/machine.c
>> +++ b/hw/core/machine.c
>> @@ -758,6 +758,41 @@ void machine_run_board_init(MachineState *machine)
>>      if (nb_numa_nodes) {
>>          machine_numa_finish_init(machine);
>>      }
>> +
>> +    /* If the machine supports the valid_cpu_types check and the user
>> +     * specified a CPU with -cpu check here that the user CPU is supported.
>> +     */
>> +    if (machine_class->valid_cpu_types && machine->cpu_type) {
>> +        ObjectClass *class = object_class_by_name(machine->cpu_type);
>> +        int i;
>> +
>> +        /* machine->cpu_type is supposed to be always a valid QOM type */
>> +        assert(class);
>> +
>> +        for (i = 0; machine_class->valid_cpu_types[i]; i++) {
>> +            if (object_class_dynamic_cast(class,
>> +                                          
>> machine_class->valid_cpu_types[i])) {
>> +                /* The user specificed CPU is in the valid field, we are
>> +                 * good to go.
>> +                 */
>> +                break;
>> +            }
>> +        }
>> +
>> +        if (!machine_class->valid_cpu_types[i]) {
>> +            /* The user specified CPU must not be a valid CPU */
>> +            error_report("Invalid CPU type: %s", machine->cpu_type);
>> +            error_printf("The valid types are: %s",
>> +                         machine_class->valid_cpu_types[0]);
>> +            for (i = 1; machine_class->valid_cpu_types[i]; i++) {
>> +                error_printf(", %s", machine_class->valid_cpu_types[i]);
>> +            }
>> +            error_printf("\n");
>> +
>> +            exit(1);
>> +        }
>> +    }
>> +
>>      machine_class->init(machine);
>>  }
>>
>> diff --git a/include/hw/boards.h b/include/hw/boards.h
>> index 156e0a5701..191a5b3cd8 100644
>> --- a/include/hw/boards.h
>> +++ b/include/hw/boards.h
>> @@ -191,6 +191,7 @@ struct MachineClass {
>>      bool has_hotpluggable_cpus;
>>      bool ignore_memory_transaction_failures;
>>      int numa_mem_align_shift;
>> +    const char **valid_cpu_types;
>>      void (*numa_auto_assign_ram)(MachineClass *mc, NodeInfo *nodes,
>>                                   int nb_nodes, ram_addr_t size);
>>
>> --
>> 2.11.0
>>
>
> --
> Eduardo