Re: [PATCH] Drivers: hv: Introduce mshv_vtl driver

[Roman Kisel <romank@linux.microsoft.com>]

On 5/8/2025 10:44 AM, Wei Liu wrote:
> On Thu, May 08, 2025 at 08:44:14AM -0700, Roman Kisel wrote:
[...]
>>
>> You seem to know for whom it is broken, would be great to share this
>> knowledge. When CONFIG_MSHV_VTL is set to "m", OpenHCL will break down
>> without additional work. So why do we need to be able to build that
>> as a module, to let someone build the firmware that doesn't work?
>>
>> So far the request comes off as absurd to me.
>>
> 
> I don't think this is an absurd request.
> 
> While obviously Microsoft will only build the code as builtin, there are
> bots that do randconfig build tests but never run the resulting binary.

Thanks, Wei, for the thorough explanation!

> 
> Thanks,
> Wei.
> 
>>>
>>> - Saurabh
>>>
>>>>
>>>>>
>>>>> here is the diff for reference:
>>>>> diff --git a/drivers/hv/Kconfig b/drivers/hv/Kconfig index
>>>>> 57dcfcb69b88..c7f21b483377 100644
>>>>> --- a/drivers/hv/Kconfig
>>>>> +++ b/drivers/hv/Kconfig
>>>>> @@ -73,7 +73,7 @@ config MSHV_ROOT
>>>>>              If unsure, say N.
>>>>>
>>>>>     config MSHV_VTL
>>>>> -       bool "Microsoft Hyper-V VTL driver"
>>>>> +       tristate "Microsoft Hyper-V VTL driver"
>>>>>            depends on HYPERV && X86_64
>>>>>            depends on TRANSPARENT_HUGEPAGE
>>>>>            depends on OF
>>>>> diff --git a/drivers/hv/Makefile b/drivers/hv/Makefile index
>>>>> 5e785dae08cc..c53a0df746b7 100644
>>>>> --- a/drivers/hv/Makefile
>>>>> +++ b/drivers/hv/Makefile
>>>>> @@ -15,9 +15,11 @@ hv_vmbus-$(CONFIG_HYPERV_TESTING)    +=
>>>>> hv_debugfs.o
>>>>>     hv_utils-y := hv_util.o hv_kvp.o hv_snapshot.o hv_utils_transport.o
>>>>>     mshv_root-y := mshv_root_main.o mshv_synic.o mshv_eventfd.o
>>>>> mshv_irq.o \
>>>>>                   mshv_root_hv_call.o mshv_portid_table.o
>>>>> +mshv_vtl-y := mshv_vtl_main.o
>>>>>
>>>>>     # Code that must be built-in
>>>>>     obj-$(subst m,y,$(CONFIG_HYPERV)) += hv_common.o -obj-$(subst
>>>>> m,y,$(CONFIG_MSHV_ROOT)) += hv_proc.o mshv_common.o
>>>>> -
>>>>> -mshv_vtl-y := mshv_vtl_main.o mshv_common.o
>>>>> +obj-$(subst m,y,$(CONFIG_MSHV_ROOT)) += hv_proc.o ifneq
>>>>> +($(CONFIG_MSHV_ROOT) $(CONFIG_MSHV_VTL),)
>>>>> +    obj-y += mshv_common.o
>>>>> +endif
>>>>>
>>>>> Regards,
>>>>> Naman
>>>>
>>>> --
>>>> Thank you,
>>>> Roman
>>>
>>
>> -- 
>> Thank you,
>> Roman
>>

-- 
Thank you,
Roman