Re: [PATCH v1 3/3] x86/tdx: Provide stub tdx_accept_memory() for non-TDX configs

Jeremi Piotrowski
2023-11-24T10:00:54Z

On 23/11/2023 15:11, Kirill A. Shutemov wrote:
> On Wed, Nov 22, 2023 at 06:01:06PM +0100, Jeremi Piotrowski wrote:
>> When CONFIG_INTEL_TDX_GUEST is not defined but CONFIG_UNACCEPTED_MEMORY=y is,
>> the kernel fails to link with an undefined reference to tdx_accept_memory from
>> arch_accept_memory. Provide a stub for tdx_accept_memory to fix the build for
>> that configuration.
>>
>> CONFIG_UNACCEPTED_MEMORY is also selected by CONFIG_AMD_MEM_ENCRYPT, and there
>> are stubs for snp_accept_memory for when it is not defined. Previously this did
>> not result in an error when CONFIG_INTEL_TDX_GUEST was not defined because the
>> branch that references tdx_accept_memory() was being discarded due to
>> DISABLE_TDX_GUEST being set.
>
> And who unsets it now?
>

Who unsets what now? DISABLE_TDX_GUEST still works the same as before, but patch 2
changed the check in arch_accept_memory() to be more specific
(cc_platform_has(CC_ATTR_TDX_MODULE_CALLS)). The stub should have been there all
along for CONFIG_AMD_MEM_ENCRPYT=y && CONFIG_INTEL_TDX_GUEST=n configs, but it
happened to work without it.