linux-kernel - [PATCH v2 15/21] x86/virt/tdx: Reset software states after TDX module shutdown

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20251001025442.427697-16-chao.gao@intel.com>
Date: Tue, 30 Sep 2025 19:52:59 -0700
From: Chao Gao <chao.gao@...el.com>
To: linux-coco@...ts.linux.dev,
	linux-kernel@...r.kernel.org,
	x86@...nel.org,
	reinette.chatre@...el.com,
	ira.weiny@...el.com,
	kai.huang@...el.com,
	dan.j.williams@...el.com,
	yilun.xu@...ux.intel.com,
	sagis@...gle.com,
	vannapurve@...gle.com,
	paulmck@...nel.org,
	nik.borisov@...e.com
Cc: Chao Gao <chao.gao@...el.com>,
	Farrah Chen <farrah.chen@...el.com>,
	"Kirill A. Shutemov" <kas@...nel.org>,
	Dave Hansen <dave.hansen@...ux.intel.com>,
	Thomas Gleixner <tglx@...utronix.de>,
	Ingo Molnar <mingo@...hat.com>,
	Borislav Petkov <bp@...en8.de>,
	"H. Peter Anvin" <hpa@...or.com>
Subject: [PATCH v2 15/21] x86/virt/tdx: Reset software states after TDX module shutdown

The TDX module requires a one-time global initialization (TDH.SYS.INIT) and
per-CPU initialization (TDH.SYS.LP.INIT) before use. These initializations
are guarded by software flags to prevent repetition.

After TDX module updates, the new TDX module requires the same global and
per-CPU initializations, but the existing software flags prevent
re-initialization.

Reset all software flags guarding the initialization flows to allow the
global and per-CPU initializations to be triggered again after updates.

Signed-off-by: Chao Gao <chao.gao@...el.com>
Tested-by: Farrah Chen <farrah.chen@...el.com>
---
 arch/x86/virt/vmx/tdx/tdx.c | 18 +++++++++++++++---
 1 file changed, 15 insertions(+), 3 deletions(-)

diff --git a/arch/x86/virt/vmx/tdx/tdx.c b/arch/x86/virt/vmx/tdx/tdx.c
index 89b51e270274..7019a149ec4b 100644
--- a/arch/x86/virt/vmx/tdx/tdx.c
+++ b/arch/x86/virt/vmx/tdx/tdx.c
@@ -54,6 +54,9 @@ static struct tdmr_info_list tdx_tdmr_list;
 static enum tdx_module_status_t tdx_module_status;
 static DEFINE_MUTEX(tdx_module_lock);
 
+static bool sysinit_done;
+static int sysinit_ret;
+
 /* All TDX-usable memory regions.  Protected by mem_hotplug_lock. */
 static LIST_HEAD(tdx_memlist);
 
@@ -68,8 +71,6 @@ static int try_init_module_global(void)
 {
 	struct tdx_module_args args = {};
 	static DEFINE_RAW_SPINLOCK(sysinit_lock);
-	static bool sysinit_done;
-	static int sysinit_ret;
 
 	lockdep_assert_irqs_disabled();
 
@@ -1194,6 +1195,7 @@ EXPORT_SYMBOL_GPL(tdx_enable);
 int tdx_module_shutdown(void)
 {
 	struct tdx_module_args args = {};
+	int ret, cpu;
 
 	/*
 	 * Shut down the TDX Module and prepare handoff data for the next
@@ -1204,7 +1206,17 @@ int tdx_module_shutdown(void)
 	 * hand-off version.
 	 */
 	args.rcx = tdx_sysinfo.handoff.module_hv;
-	return seamcall_prerr(TDH_SYS_SHUTDOWN, &args);
+	ret = seamcall_prerr(TDH_SYS_SHUTDOWN, &args);
+	if (ret)
+		return ret;
+
+	tdx_module_status = TDX_MODULE_UNINITIALIZED;
+	sysinit_done = false;
+	sysinit_ret = 0;
+
+	for_each_online_cpu(cpu)
+		per_cpu(tdx_lp_initialized, cpu) = false;
+	return 0;
 }
 
 static bool is_pamt_page(unsigned long phys)
-- 
2.47.3