Re: [Qemu-devel] [PATCH 12/16] target-i386: cpu: attach ICC bus to CPU on its creation

[Andreas Färber]

Am 22.04.2013 17:20, schrieb Igor Mammedov:
> On Mon, 22 Apr 2013 17:02:33 +0200
> Andreas Färber <address@hidden> wrote:
> 
>> Am 16.04.2013 00:12, schrieb Igor Mammedov:
>>> ... during startup,  so it would be possible to unplug it later
>>> and set bus_type to TYPE_ICC_BUS for X86CPU type to make device_add
>>> attach hotplugged CPU to ICC bus.
>>>
>>> Signed-off-by: Igor Mammedov <address@hidden>
>>
>> Reviewed-by: Andreas Färber <address@hidden>
>>
>> But still one question...
>>
>>> ---
>>>  target-i386/cpu.c | 7 +++++++
>>>  1 file changed, 7 insertions(+)
>>>
>>> diff --git a/target-i386/cpu.c b/target-i386/cpu.c
>>> index 6d6c527..3b5f90b 100644
>>> --- a/target-i386/cpu.c
>>> +++ b/target-i386/cpu.c
>>> @@ -41,6 +41,7 @@
>>>  #endif
>>>  
>>>  #include "sysemu/sysemu.h"
>>> +#include "hw/i386/icc_bus.h"
>>>  #ifndef CONFIG_USER_ONLY
>>>  #include "hw/xen/xen.h"
>>>  #include "hw/sysbus.h"
>>> @@ -1609,6 +1610,7 @@ X86CPU *cpu_x86_create(const char *cpu_model, Error
>>> **errp) gchar **model_pieces;
>>>      char *name, *features;
>>>      Error *error = NULL;
>>> +    Object *icc_bus = object_resolve_path_type("icc-bus", TYPE_ICC_BUS,
>>> NULL); 
>>>      model_pieces = g_strsplit(cpu_model, ",", 2);
>>>      if (!model_pieces[0]) {
>>> @@ -1619,6 +1621,10 @@ X86CPU *cpu_x86_create(const char *cpu_model,
>>> Error **errp) features = model_pieces[1];
>>>  
>>>      cpu = X86_CPU(object_new(TYPE_X86_CPU));
>>> +    if (icc_bus) {
>>> +        qdev_set_parent_bus(DEVICE(cpu), BUS(icc_bus));
>>> +        object_unref(OBJECT(cpu));
>>> +    }
>>>      env = &cpu->env;
>>>      env->cpu_model_str = cpu_model;
>>>  
>>
>> You seem to be avoiding making lack of icc-bus an error although you add
>> it for both PC and q35 PC - which non-ICC use cases are you thinking of?
> *-user targets, CPU is bus-less there.

Would you be opposed to #ifdef'ing it then? In particular I am asking
because of the NULL error argument to the resolve function - for softmmu
I would prefer to make lack of icc-bus a fatal error.

Andreas

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