[PATCH v2 6/6] x86/vmware: Add TDX hypercall support

[Alexey Makhalov]

On 12/5/23 1:24 PM, Dave Hansen wrote:
> On 12/4/23 02:31, Borislav Petkov wrote:
>> On Fri, Dec 01, 2023 at 03:24:52PM -0800, Alexey Makhalov wrote:
>>> +#ifdef CONFIG_INTEL_TDX_GUEST
>>> +/* __tdx_hypercall() is not exported. So, export the wrapper */
>>> +void vmware_tdx_hypercall_args(struct tdx_module_args *args)
>>> +{
>>> +	__tdx_hypercall(args);
>>> +}
>>> +EXPORT_SYMBOL_GPL(vmware_tdx_hypercall_args);
>> Uuuh, lovely. I'd like to see what the TDX folks think about this
>> export first.
> 
> I don't really like it much.  This does a generic thing (make a TDX
> hypercall) with a specific name ("vmware_").  If you want to make an
> argument that a certain chunk of the __tdx_hypercall() space is just for
> VMWare and you also add a VMWare-specific check and then export *that*,
> it might be acceptable.
> 
> But I don't want random modules able to make random, unrestricted TDX
> hypercalls.  That's asking for trouble.

Considering exporting of __tdx_hypercall for random modules is not an 
option, what VMware specific checks you are suggesting?

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