Re: [PATCH] x86/hypercall: fix gnttab hypercall args conditional build on pvshim

[Jan Beulich <jbeulich@xxxxxxxx>]

On 08.01.2021 16:24, Jan Beulich wrote:
> On 08.01.2021 16:11, Roger Pau Monné wrote:
>> On Fri, Jan 08, 2021 at 04:01:52PM +0100, Jan Beulich wrote:
>>> On 08.01.2021 15:41, Roger Pau Monne wrote:
>>>> --- a/xen/arch/x86/hypercall.c
>>>> +++ b/xen/arch/x86/hypercall.c
>>>> @@ -47,7 +47,7 @@ const hypercall_args_t 
>>>> hypercall_args_table[NR_hypercalls] =
>>>>      ARGS(xen_version, 2),
>>>>      ARGS(console_io, 3),
>>>>      ARGS(physdev_op_compat, 1),
>>>> -#ifdef CONFIG_GRANT_TABLE
>>>> +#if defined(CONFIG_GRANT_TABLE) || defined(CONFIG_PV_SHIM)
>>>>      ARGS(grant_table_op, 3),
>>>>  #endif
>>>>      ARGS(vm_assist, 2),
>>>
>>> This is correct when a shim-enabled build runs as shim, but
>>> not when it runs as normal hypervisor. Just like the hypercall
>>> handler gets patched into the hypercall table (in
>>> pv_shim_setup_dom()), the argument count will also want
>>> updating there, I think.
>>
>> Having the argument count set when the hypercall handler is NULL is
>> fine, as Xen won't get into processing hypercall_args_table if the
>> handler is NULL.
> 
> Oh, good point.

Albeit then - why not drop the #ifdef altogether?

Jan