Re: [Qemu-devel] [PATCH uq/master v2 1/2] kvm: reset state from the CPU's reset method

["Andreas Färber" <afaerber@suse.de>]

Am 08.04.2013 14:19, schrieb Gleb Natapov:
> On Tue, Apr 02, 2013 at 04:29:32PM +0300, Gleb Natapov wrote:
>>>  static void kvm_sw_tlb_put(PowerPCCPU *cpu)
>>>  {
>>>      CPUPPCState *env = &cpu->env;
>>> diff --git a/target-s390x/cpu.c b/target-s390x/cpu.c
>>> index 23fe51f..6321384 100644
>>> --- a/target-s390x/cpu.c
>>> +++ b/target-s390x/cpu.c
>>> @@ -84,6 +84,10 @@ static void s390_cpu_reset(CPUState *s)
>>>       * after incrementing the cpu counter */
>>>  #if !defined(CONFIG_USER_ONLY)
>>>      s->halted = 1;
>>> +
>>> +    if (kvm_enabled()) {
>>> +        kvm_arch_reset_vcpu(s);
>> Does this compile with kvm support disabled?
>>
> Well, it does not:
>   CC    s390x-softmmu/target-s390x/cpu.o
> /users/gleb/work/qemu/target-s390x/cpu.c: In function 's390_cpu_reset':
> /users/gleb/work/qemu/target-s390x/cpu.c:89:9: error: implicit
> declaration of function 'kvm_arch_reset_vcpu'
> [-Werror=implicit-function-declaration]
> /users/gleb/work/qemu/target-s390x/cpu.c:89:9: error: nested extern
> declaration of 'kvm_arch_reset_vcpu' [-Werror=nested-externs]
> cc1: all warnings being treated as errors
> 
> I wonder if it is portable between compilers to rely on code in if(0){} to
> be dropped in all levels of optimizations.

No, we had a previous case where --enable-debug broke if (kvm_enabled())
{...} but regular builds worked.

Andreas

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