>+static void __do_tdx_cleanup(void)
>+{
>+ /*
>+ * Once TDX module is initialized, it cannot be disabled and
>+ * re-initialized again w/o runtime update (which isn't
>+ * supported by kernel). Only need to remove the cpuhp here.
>+ * The TDX host core code tracks TDX status and can handle
>+ * 'multiple enabling' scenario.
>+ */
>+ WARN_ON_ONCE(!tdx_cpuhp_state);
>+ cpuhp_remove_state_nocalls(tdx_cpuhp_state);
...
>+static int __init __do_tdx_bringup(void)
>+{
>+ int r;
>+
>+ /*
>+ * TDX-specific cpuhp callback to call tdx_cpu_enable() on all
>+ * online CPUs before calling tdx_enable(), and on any new
>+ * going-online CPU to make sure it is ready for TDX guest.
>+ */
>+ r = cpuhp_setup_state_cpuslocked(CPUHP_AP_ONLINE_DYN,
>+ "kvm/cpu/tdx:online",
>+ tdx_online_cpu, NULL);
>+ if (r < 0)
>+ return r;
>+
>+ tdx_cpuhp_state = r;
>+
>+ r = tdx_enable();
>+ if (r)
>+ __do_tdx_cleanup();
The self deadlock issue isn't addressed.
>+
>+ return r;
>+}
>+
>+static bool __init kvm_can_support_tdx(void)
>+{
>+ return cpu_feature_enabled(X86_FEATURE_TDX_HOST_PLATFORM);
...
>+int __init tdx_bringup(void)
>+{
>+ int r;
>+
>+ if (!enable_tdx)
>+ return 0;
>+
>+ if (!kvm_can_support_tdx()) {
>+ pr_err("tdx: no TDX private KeyIDs available\n");
The lack of X86_FEATURE_TDX_HOST_PLATFORM doesn't necessarily mean no TDX
private KeyIDs. In tdx_init(), X86_FEATURE_TDX_HOST_PLATFORM is not set if
hibernation is enabled.
>+ goto success_disable_tdx;
>+ }
>+
>+ if (!enable_virt_at_load) {
>+ pr_err("tdx: tdx requires kvm.enable_virt_at_load=1\n");
>+ goto success_disable_tdx;
>+ }
>+
>+ /*
>+ * Ideally KVM should probe whether TDX module has been loaded
>+ * first and then try to bring it up. But TDX needs to use SEAMCALL
>+ * to probe whether the module is loaded (there is no CPUID or MSR
>+ * for that), and making SEAMCALL requires enabling virtualization
>+ * first, just like the rest steps of bringing up TDX module.
>+ *
>+ * So, for simplicity do everything in __tdx_bringup(); the first
>+ * SEAMCALL will return -ENODEV when the module is not loaded. The
>+ * only complication is having to make sure that initialization
>+ * SEAMCALLs don't return TDX_SEAMCALL_VMFAILINVALID in other
>+ * cases.
>+ */
>+ r = __tdx_bringup();
>+ if (r) {
>+ /*
>+ * Disable TDX only but don't fail to load module if
>+ * the TDX module could not be loaded. No need to print
>+ * message saying "module is not loaded" because it was
>+ * printed when the first SEAMCALL failed.
>+ */
>+ if (r == -ENODEV)
>+ goto success_disable_tdx;
Given that two error messages are added above, I think it is worth adding one
more here for consistency. And, reloading KVM will not trigger the "module is
not loaded" error which is printed once.
>+
>+ enable_tdx = 0;
>+ }
>+
>+ return r;
>+
>+success_disable_tdx:
>+ enable_tdx = 0;
>+ return 0;
>+}
