Re: [Qemu-devel] [PATCH 1/1] target-i386: Remove icc_bridge parameter from cpu_x86_create()

["Andreas Färber" <afaerber@suse.de>]

Am 10.03.2015 um 14:30 schrieb Eduardo Habkost:
> On Tue, Mar 10, 2015 at 02:22:01PM +0100, Andreas Färber wrote:
>> Am 05.03.2015 um 18:26 schrieb Eduardo Habkost:
>>> Instead of passing icc_bridge from the PC initialization code to
>>> cpu_x86_create(), make the PC initialization code attach the CPU to
>>> icc_bridge.
>>>
>>> The only difference here is that icc_bridge attachment will now be done
>>> after x86_cpu_parse_featurestr() is called. But this shouldn't make any
>>> difference, as property setters shouldn't depend on icc_bridge.
>>>
>>> Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
>>> ---
>>>  hw/i386/pc.c      |  6 +++++-
>>>  target-i386/cpu.c | 14 ++------------
>>>  target-i386/cpu.h |  3 +--
>>>  3 files changed, 8 insertions(+), 15 deletions(-)
>>>
>>> diff --git a/hw/i386/pc.c b/hw/i386/pc.c
>>> index ed54d93..66b9fa6 100644
>>> --- a/hw/i386/pc.c
>>> +++ b/hw/i386/pc.c
>>> @@ -995,12 +995,16 @@ static X86CPU *pc_new_cpu(const char *cpu_model, int64_t apic_id,
>>>      X86CPU *cpu;
>>>      Error *local_err = NULL;
>>>  
>>> -    cpu = cpu_x86_create(cpu_model, icc_bridge, &local_err);
>>> +    cpu = cpu_x86_create(cpu_model, &local_err);
>>>      if (local_err != NULL) {
>>>          error_propagate(errp, local_err);
>>>          return NULL;
>>>      }
>>>  
>>> +    assert(icc_bridge);
>>
>> On second thoughts, why are you asserting here rather than setting errp?
>> Just add an out: below and goto out, like I did.
>>
>> On startup it doesn't matter much, but for hot-add asserting would not
>> be so nice.
> 
> Because not having icc_bus passed as argument would be a coding error.
> 
> Also, I have no idea what kind of things would break if we destroy a CPU
> after cpu_exec_init() was already called in instance_init.

Then do it before cpu_x86_create()! :)

Also, every memory allocation failure can result in an assertion (which
is why I'm trying to cut down on their number).

Andreas

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