Merge tag 'x86_tdx_for_7.2-rc1' of gitolite.kernel.org:pub/scm/linux/kernel/git/tip/tip

Pull x86 TDX updates from Dave Hansen:
"There are a few cleanups, and some changes that should allow TDX and

Merge tag 'x86_tdx_for_7.2-rc1' of gitolite.kernel.org:pub/scm/linux/kernel/git/tip/tip

Pull x86 TDX updates from Dave Hansen:
"There are a few cleanups, and some changes that should allow TDX and
kexec to coexist nicely.

The biggest change, however, is support for updating the TDX module
after boot, just like CPU microcode. TDX users really want this
because it lets them do security updates without tearing things down
and rebooting.

- Add TDX module update support

- Make kexec and TDX finally place nice together

- Put TDX error codes into a single header"

* tag 'x86_tdx_for_7.2-rc1' of gitolite.kernel.org:pub/scm/linux/kernel/git/tip/tip: (30 commits)
x86/virt/tdx: Document TDX module update
x86/virt/tdx: Enable TDX module runtime updates
x86/virt/tdx: Refresh TDX module version after update
coco/tdx-host: Lock out module updates when reading version
x86/virt/seamldr: Add module update locking
x86/virt/tdx: Restore TDX module state
x86/virt/seamldr: Initialize the newly-installed TDX module
x86/virt/seamldr: Install a new TDX module
x86/virt/tdx: Reset software states during TDX module shutdown
x86/virt/seamldr: Shut down the current TDX module
x86/virt/seamldr: Abort updates after a failed step
x86/virt/seamldr: Introduce skeleton for TDX module updates
x86/virt/seamldr: Allocate and populate a module update request
coco/tdx-host: Implement firmware upload sysfs ABI for TDX module updates
coco/tdx-host: Don't expose P-SEAMLDR information on CPUs with erratum
coco/tdx-host: Expose P-SEAMLDR information via sysfs
x86/virt/seamldr: Add a helper to retrieve P-SEAMLDR information
x86/virt/seamldr: Introduce a wrapper for P-SEAMLDR SEAMCALLs
coco/tdx-host: Expose TDX module version
coco/tdx-host: Introduce a "tdx_host" device
...

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coco/tdx-host: Introduce a "tdx_host" device

TDX depends on a platform firmware module that runs on the CPU.
Unlike other CoCo architectures, TDX has no hardware "device"
running the show, just a bl

coco/tdx-host: Introduce a "tdx_host" device

TDX depends on a platform firmware module that runs on the CPU.
Unlike other CoCo architectures, TDX has no hardware "device"
running the show, just a blob on the CPU.

Create a virtual device to anchor interactions with this platform
firmware. This lets later code:

- expose metadata: TDX module version, seamldr version, to userspace
as device attributes

- implement firmware uploader APIs (which are tied to a device) to
support TDX module runtime updates

Use a faux device because the TDX module is singular within the system
and has no platform resources. Using a faux device eliminates the need
to create a stub bus.

The call to tdx_get_sysinfo() ensures that the TDX module is ready to
provide services.

Note that AMD has a PCI device for the PSP for SEV and ARM CCA will
likely have a faux device [1].

Thanks to Dan and Yilun for all the help on this one.

[ dhansen: trim changelog ]

Signed-off-by: Chao Gao <chao.gao@intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Reviewed-by: Tony Lindgren <tony.lindgren@linux.intel.com>
Reviewed-by: Xu Yilun <yilun.xu@linux.intel.com>
Reviewed-by: Kai Huang <kai.huang@intel.com>
Reviewed-by: Kiryl Shutsemau (Meta) <kas@kernel.org>
Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com>
Link: https://lore.kernel.org/all/2025073035-bulginess-rematch-b92e@gregkh/ # [1]
Link: https://patch.msgid.link/20260520133909.409394-7-chao.gao@intel.com

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