Re: [Qemu-devel] [PATCH 2/3] update kvm related the head file from kernel

[Jan Kiszka]

On 2012-09-07 11:39, Xiao Guangrong wrote:
> Hi Jan,
> 
> Thanks for your review.
> 
> On 09/07/2012 04:49 PM, Jan Kiszka wrote:
> 
>>> +#ifdef __KVM_HAVE_READONLY_MEM
>>> +                   __u8 write_readonly_mem;
>>> +#endif
>>>             } mmio;
>>>             /* KVM_EXIT_HYPERCALL */
>>>             struct {
>>> @@ -618,6 +625,9 @@ struct kvm_ppc_smmu_info {
>>>  #define KVM_CAP_PPC_GET_SMMU_INFO 78
>>>  #define KVM_CAP_S390_COW 79
>>>  #define KVM_CAP_PPC_ALLOC_HTAB 80
>>> +#ifdef __KVM_HAVE_READONLY_MEM
>>> +#define KVM_CAP_READONLY_MEM 81
>>> +#endif
>>
>> Sorry for commenting on the wrong patch, this must be fixed in the
>> kernel: no more conditional CAPs, please. 
> 
> There are some common code depend on KVM_CAP_READONLY_MEM, such as,

Let is depend on KVM_HAVE or some CONFIG_xxx, not on something that is
going to be exported as userspace API.

Jan

> check_memory_region_flags() and write_readonly_mem field in mmio-exit-info.
> 
> Yes, we can use #ifdef CONFIG_X86 to enable it only on x86, but it
> is hard to expand this feather to other arches in the further.
> 
> So, i used __KVM_HAVE_READONLY_MEM and only defined it on x86. :)
> 

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