=== Problem & Solution ===

Currently, there is neither an ABI, nor any other way to determine from
the host system, what version of the TDX module is running. A sysfs ABI
for this has been proposed in [1], but it may need additional discussion.

Many/most TDX developers already carry patches like this in their
development branches. It can be tricky to know which TDX module is
actually loaded on a system, and so this functionality has been needed
regularly for development and processing bug reports. Hence, it is
prudent to break out the patches to retrieve and print the TDX module
version, as those parts are very straightforward, and get some level of
debugability and traceability for TDX host systems.

=== Dependencies ===

None. This is based on v6.19-rc4, and applies cleanly to tip.git.

=== Patch details ===

Patch 1 is a prerequisite that adds the infrastructure to retrieve the
TDX module version from its global metadata. This was originally posted in [2].

Patch 2 is based on a patch from Kai Huang [3], and prints the version to
dmesg during init.

=== Testing ===

This has passed the usual suite of tests, including successful 0day
builds, KVM Unit tests, KVM selftests, a TD creation smoke test, and
selected KVM tests from the Avocado test suite.

[1]: https://lore.kernel.org/all/20260105074350.98564-1-chao.gao@intel.com/
[2]: https://lore.kernel.org/all/20260105074350.98564-2-chao.gao@intel.com/
[3]: https://lore.kernel.org/all/57eaa1b17429315f8b5207774307f3c1dd40cf37.1730118186.git.kai.huang@intel.com/

Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
---
Changes in v2:
- Collect review tags (Kiryl, Rick)
- Reword commit messages for clarity (Rick)
- Move the version print get_tdx_sys_info() (Kiryl, Dave)
- Link to v1: https://patch.msgid.link/20260107-tdx_print_module_version-v1-0-822baa56762d@intel.com

---
Chao Gao (1):
      x86/virt/tdx: Retrieve TDX module version

Vishal Verma (1):
      x86/virt/tdx: Print TDX module version during init

 arch/x86/include/asm/tdx_global_metadata.h  |  7 +++++++
 arch/x86/virt/vmx/tdx/tdx_global_metadata.c | 22 ++++++++++++++++++++++
 2 files changed, 29 insertions(+)
---
base-commit: 9ace4753a5202b02191d54e9fdf7f9e3d02b85eb
change-id: 20260107-tdx_print_module_version-e4ca7edc2022

Best regards,
--  
Vishal Verma <vishal.l.verma@intel.com>

On Fri, 2026-01-09 at 12:14 -0700, Vishal Verma wrote:
> === Problem & Solution ===
> 
> Currently, there is neither an ABI, nor any other way to determine from
> the host system, what version of the TDX module is running. A sysfs ABI
> for this has been proposed in [1], but it may need additional discussion.
> 
> Many/most TDX developers already carry patches like this in their
> development branches. It can be tricky to know which TDX module is
> actually loaded on a system, and so this functionality has been needed
> regularly for development and processing bug reports. Hence, it is
> prudent to break out the patches to retrieve and print the TDX module
> version, as those parts are very straightforward, and get some level of
> debugability and traceability for TDX host systems.
> 
> === Dependencies ===
> 
> None. This is based on v6.19-rc4, and applies cleanly to tip.git.
> 
> === Patch details ===
> 
> Patch 1 is a prerequisite that adds the infrastructure to retrieve the
> TDX module version from its global metadata. This was originally posted in [2].
> 
> Patch 2 is based on a patch from Kai Huang [3], and prints the version to
> dmesg during init.
> 
> === Testing ===
> 
> This has passed the usual suite of tests, including successful 0day
> builds, KVM Unit tests, KVM selftests, a TD creation smoke test, and
> selected KVM tests from the Avocado test suite.
> 
> [1]: https://lore.kernel.org/all/20260105074350.98564-1-chao.gao@intel.com/
> [2]: https://lore.kernel.org/all/20260105074350.98564-2-chao.gao@intel.com/
> [3]: https://lore.kernel.org/all/57eaa1b17429315f8b5207774307f3c1dd40cf37.1730118186.git.kai.huang@intel.com/
> 
> Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>

Hi Kiryl, just wanted to check on the plan for this, I didn't see it
merged in tip.git x86/tdx (or any other tip branch). Were you planning
to take it through x86/tdx? Can I help with anything to move it along?

Thank you,
Vishal

On Thu, Feb 05, 2026 at 07:05:39PM +0000, Verma, Vishal L wrote:
> On Fri, 2026-01-09 at 12:14 -0700, Vishal Verma wrote:
> > === Problem & Solution ===
> > 
> > Currently, there is neither an ABI, nor any other way to determine from
> > the host system, what version of the TDX module is running. A sysfs ABI
> > for this has been proposed in [1], but it may need additional discussion.
> > 
> > Many/most TDX developers already carry patches like this in their
> > development branches. It can be tricky to know which TDX module is
> > actually loaded on a system, and so this functionality has been needed
> > regularly for development and processing bug reports. Hence, it is
> > prudent to break out the patches to retrieve and print the TDX module
> > version, as those parts are very straightforward, and get some level of
> > debugability and traceability for TDX host systems.
> > 
> > === Dependencies ===
> > 
> > None. This is based on v6.19-rc4, and applies cleanly to tip.git.
> > 
> > === Patch details ===
> > 
> > Patch 1 is a prerequisite that adds the infrastructure to retrieve the
> > TDX module version from its global metadata. This was originally posted in [2].
> > 
> > Patch 2 is based on a patch from Kai Huang [3], and prints the version to
> > dmesg during init.
> > 
> > === Testing ===
> > 
> > This has passed the usual suite of tests, including successful 0day
> > builds, KVM Unit tests, KVM selftests, a TD creation smoke test, and
> > selected KVM tests from the Avocado test suite.
> > 
> > [1]: https://lore.kernel.org/all/20260105074350.98564-1-chao.gao@intel.com/
> > [2]: https://lore.kernel.org/all/20260105074350.98564-2-chao.gao@intel.com/
> > [3]: https://lore.kernel.org/all/57eaa1b17429315f8b5207774307f3c1dd40cf37.1730118186.git.kai.huang@intel.com/
> > 
> > Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
> 
> Hi Kiryl, just wanted to check on the plan for this, I didn't see it
> merged in tip.git x86/tdx (or any other tip branch). Were you planning
> to take it through x86/tdx? Can I help with anything to move it along?

I guess it has to wait after the merge window at this point.

Dave, could you queue this after -rc1 is tagged?

-- 
  Kiryl Shutsemau / Kirill A. Shutemov

On 2/6/26 03:39, Kiryl Shutsemau wrote:
>> Hi Kiryl, just wanted to check on the plan for this, I didn't see it
>> merged in tip.git x86/tdx (or any other tip branch). Were you planning
>> to take it through x86/tdx? Can I help with anything to move it along?
> I guess it has to wait after the merge window at this point.
> 
> Dave, could you queue this after -rc1 is tagged?

Sure.

Is there any other TDX stuff that needs to get picked up at the same
time that's been languishing?

On Fri, 2026-02-06 at 07:10 -0800, Dave Hansen wrote:
> Is there any other TDX stuff that needs to get picked up at the same
> time that's been languishing?

Xiaoyao is going to send a rebase of this after RC1:
https://lore.kernel.org/kvm/20250715091312.563773-1-xiaoyao.li@intel.com/

It has pretty wide agreement, and ack's from the KVM side. Also, we have
internal branches that are carrying forms of it. So if we merge it now we can
have less dependencies later.

On Fri, 2026-01-09 at 12:14 -0700, Verma, Vishal L wrote:
> === Problem & Solution ===
> 
> Currently, there is neither an ABI, nor any other way to determine from
> the host system, what version of the TDX module is running. A sysfs ABI
> for this has been proposed in [1], but it may need additional discussion.
> 
> Many/most TDX developers already carry patches like this in their
> development branches. It can be tricky to know which TDX module is
> actually loaded on a system, and so this functionality has been needed
> regularly for development and processing bug reports. Hence, it is
> prudent to break out the patches to retrieve and print the TDX module
> version, as those parts are very straightforward, and get some level of
> debugability and traceability for TDX host systems.

Big thanks for picking this up:

Reviewed-by: Kai Huang <kai.huang@intel.com>