[tip: x86/tdx] x86/virt/seamldr: Initialize the newly-installed TDX module

["tip-bot2 for Chao Gao" <tip-bot2@linutronix.de>]

The following commit has been merged into the x86/tdx branch of tip:

Commit-ID:     ae1b7dc35a2309b5493eeb2e56275617f1de8e13
Gitweb:        https://git.kernel.org/tip/ae1b7dc35a2309b5493eeb2e56275617f1de8e13
Author:        Chao Gao <chao.gao@intel.com>
AuthorDate:    Wed, 20 May 2026 15:29:09 -07:00
Committer:     Dave Hansen <dave.hansen@linux.intel.com>
CommitterDate: Wed, 20 May 2026 15:37:11 -07:00

x86/virt/seamldr: Initialize the newly-installed TDX module

Continue fleshing out the update process. At this point new the new
module is installed but is not usable. It is in a similar state to the
when the system first boots.

TODO: this is nonsense. What is *MISSING*?!?!?

>>>This post-update initialization differs from the initial boot-time
>>>initialization. It only needs TDX global initialization, TDX per-CPU
>>>initialization, and restoration of TDX state from the handoff data.

After installing a new TDX module, the kernel must re-initialize TDX
before resuming TDX operations.

tdx_cpu_enable() covers the global and per-CPU initialization. Export it
and invoke it on all CPUs.

Signed-off-by: Chao Gao <chao.gao@intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Xu Yilun <yilun.xu@linux.intel.com>
Reviewed-by: Tony Lindgren <tony.lindgren@linux.intel.com>
Reviewed-by: Kai Huang <kai.huang@intel.com>
Reviewed-by: Kiryl Shutsemau (Meta) <kas@kernel.org>
Reviewed-by: Rick Edgecombe <rick.p.edgecombe@intel.com>
Link: https://patch.msgid.link/20260520133909.409394-20-chao.gao@intel.com
Link: https://patch.msgid.link/20260520222909.466B929B@davehans-spike.ostc.intel.com
---
 arch/x86/include/asm/tdx.h      | 1 +
 arch/x86/virt/vmx/tdx/seamldr.c | 4 ++++
 arch/x86/virt/vmx/tdx/tdx.c     | 2 +-
 3 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/arch/x86/include/asm/tdx.h b/arch/x86/include/asm/tdx.h
index 27376db..5d750fe 100644
--- a/arch/x86/include/asm/tdx.h
+++ b/arch/x86/include/asm/tdx.h
@@ -107,6 +107,7 @@ static inline long tdx_kvm_hypercall(unsigned int nr, unsigned long p1,
 
 #ifdef CONFIG_INTEL_TDX_HOST
 void tdx_init(void);
+int tdx_cpu_enable(void);
 const char *tdx_dump_mce_info(struct mce *m);
 const struct tdx_sys_info *tdx_get_sysinfo(void);
 
diff --git a/arch/x86/virt/vmx/tdx/seamldr.c b/arch/x86/virt/vmx/tdx/seamldr.c
index 54fa797..5fdb36b 100644
--- a/arch/x86/virt/vmx/tdx/seamldr.c
+++ b/arch/x86/virt/vmx/tdx/seamldr.c
@@ -209,6 +209,7 @@ enum module_update_state {
 	MODULE_UPDATE_START,
 	MODULE_UPDATE_SHUTDOWN,
 	MODULE_UPDATE_CPU_INSTALL,
+	MODULE_UPDATE_CPU_INIT,
 	MODULE_UPDATE_DONE,
 };
 
@@ -287,6 +288,9 @@ static int do_seamldr_install_module(void *seamldr_params)
 		case MODULE_UPDATE_CPU_INSTALL:
 			ret = seamldr_install(seamldr_params);
 			break;
+		case MODULE_UPDATE_CPU_INIT:
+			ret = tdx_cpu_enable();
+			break;
 		default:
 			break;
 		}
diff --git a/arch/x86/virt/vmx/tdx/tdx.c b/arch/x86/virt/vmx/tdx/tdx.c
index 37e52cd..080a2bc 100644
--- a/arch/x86/virt/vmx/tdx/tdx.c
+++ b/arch/x86/virt/vmx/tdx/tdx.c
@@ -113,7 +113,7 @@ out:
  * (and TDX module global initialization SEAMCALL if not done) on local cpu to
  * make this cpu be ready to run any other SEAMCALLs.
  */
-static int tdx_cpu_enable(void)
+int tdx_cpu_enable(void)
 {
 	struct tdx_module_args args = {};
 	int ret;