Re: [XEN][PATCH v2 3/4] x86: hvm: factor out COMPAT code under ifdefs

[Grygorii Strashko <grygorii_strashko@epam.com>]

On 02.12.25 21:26, Jason Andryuk wrote:
> On 2025-11-19 14:30, Grygorii Strashko wrote:
>> From: Grygorii Strashko <grygorii_strashko@epam.com>
>>
>> Factor out COMPAT HVM code under ifdefs in preparation for making HVM
>> COMPAT code optional.
>>
>> - hypercall-defs.c updated to always provide compat declaration for:
>> physdev_op, grant_table_op, grant_table_op. This reduces number of COMPAT
>> ifdefs in HVM code and lets compiler DCE do the job.
>>
>> - Only 64-bit shinfo is supported with COMPAT=n, so struct
>> arch_domain->has_32bit_shinfo field is moved under COMPAT ifdef and
>> has_32bit_shinfo() is updated to account for COMPAT=n.
>>
>> Signed-off-by: Grygorii Strashko <grygorii_strashko@epam.com>
> 
>> diff --git a/xen/arch/x86/include/asm/domain.h b/xen/arch/x86/include/asm/domain.h
>> index 5df8c7825333..0005f4450931 100644
>> --- a/xen/arch/x86/include/asm/domain.h
>> +++ b/xen/arch/x86/include/asm/domain.h
>> @@ -12,8 +12,11 @@
>>   #include <public/vcpu.h>
>>   #include <public/hvm/hvm_info_table.h>
>> -#define has_32bit_shinfo(d)    ((d)->arch.has_32bit_shinfo)
>> -
>> +#ifdef CONFIG_COMPAT
>> +#define has_32bit_shinfo(d) ((d)->arch.has_32bit_shinfo)
>> +#else
>> +#define has_32bit_shinfo(d) ((void)(d), false)
> 
> (void)(d) is to avoid an any potential unreferenced 'd' messages?

It's a generic request to have macro arguments evaluated consistently.

> 
> Just using false builds for me, but your way is a little more robust.
> 
>> +#endif
>>   /*
>>    * Set to true if either the global vector-type callback or per-vCPU
>>    * LAPIC vectors are used. Assume all vCPUs will use
> Reviewed-by: Jason Andryuk <jason.andryuk@amd.com>
> 
> Regards,
> Jason

-- 
Best regards,
-grygorii