Re: [PATCH v4 20/24] xen/x86: wrap x86-specific domctl-op with CONFIG_MGMT_HYPERCALLS

[Jan Beulich <jbeulich@xxxxxxxx>]

On 04.12.2025 05:23, Penny, Zheng wrote:
> [Public]
> 
>> -----Original Message-----
>> From: Jan Beulich <jbeulich@xxxxxxxx>
>> Sent: Wednesday, November 26, 2025 1:00 AM
>> To: Penny, Zheng <penny.zheng@xxxxxxx>
>> Cc: Huang, Ray <Ray.Huang@xxxxxxx>; grygorii_strashko@xxxxxxxx; Andrew
>> Cooper <andrew.cooper3@xxxxxxxxxx>; Anthony PERARD
>> <anthony.perard@xxxxxxxxxx>; Orzel, Michal <Michal.Orzel@xxxxxxx>; Julien
>> Grall <julien@xxxxxxx>; Roger Pau Monné <roger.pau@xxxxxxxxxx>; Stefano
>> Stabellini <sstabellini@xxxxxxxxxx>; Daniel P. Smith
>> <dpsmith@xxxxxxxxxxxxxxxxxxxx>; xen-devel@xxxxxxxxxxxxxxxxxxxx
>> Subject: Re: [PATCH v4 20/24] xen/x86: wrap x86-specific domctl-op with
>> CONFIG_MGMT_HYPERCALLS
>>
>> On 21.11.2025 11:57, Penny Zheng wrote:
>>> --- a/xen/arch/x86/Kconfig
>>> +++ b/xen/arch/x86/Kconfig
>>> @@ -29,7 +29,7 @@ config X86
>>>     select HAS_PCI_MSI
>>>     select HAS_PIRQ
>>>     select HAS_SCHED_GRANULARITY
>>> -   imply HAS_SOFT_RESET
>>> +   select HAS_SOFT_RESET if MGMT_HYPERCALLS
>>
>> Why would you undo an "imply", when really we should use it more? One of its
>> purposes is so that you can add "depends on MGMT_HYPERCALLS" there, and it
>> then won't be auto-enabled if that dependency isn't fulfilled.
>>
>>> --- a/xen/arch/x86/include/asm/paging.h
>>> +++ b/xen/arch/x86/include/asm/paging.h
>>> @@ -55,7 +55,7 @@
>>>  #define PG_translate   0
>>>  #define PG_external    0
>>>  #endif
>>> -#if defined(CONFIG_PAGING) && !defined(CONFIG_PV_SHIM_EXCLUSIVE)
>>> +#if defined(CONFIG_PAGING) && !defined(CONFIG_PV_SHIM_EXCLUSIVE)
>> &&
>>> +defined(CONFIG_MGMT_HYPERCALLS)
>>
>> This line is too long now.
> 
> Hmm, how about I introduce a new Kconfig, something like:
> ```
> diff --git a/xen/arch/x86/Kconfig b/xen/arch/x86/Kconfig
> index c808c989fc..ec8f51b0b1 100644
> --- a/xen/arch/x86/Kconfig
> +++ b/xen/arch/x86/Kconfig
> @@ -166,6 +166,9 @@ config SHADOW_PAGING
>  config PAGING
>         def_bool HVM || SHADOW_PAGING
> 
> +config PAGING_LOG_DIRTY
> +       def_bool PAGING
> +
>  config BIGMEM
>         bool "big memory support"
>         default n
> ```
> Then, later future dependency could be added to PAGING_LOG_DIRTY

I fear I don't see how having an option merely aliasing another option
would help the line length issue. I may simply be missing some context ...

Jan