summaryrefslogtreecommitdiff
path: root/arch/x86/kernel/head64.c
diff options
context:
space:
mode:
authorKuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>2022-04-06 02:29:10 +0300
committerDave Hansen <dave.hansen@linux.intel.com>2022-04-07 08:27:50 -0700
commit59bd54a84d15e9335de5b8abe7b3b9713a36b99b (patch)
tree092fe681be97bfa61b235a9b494114a881180ab0 /arch/x86/kernel/head64.c
parent3123109284176b1532874591f7c81f3837bbdc17 (diff)
x86/tdx: Detect running as a TDX guest in early boot
In preparation of extending cc_platform_has() API to support TDX guest, use CPUID instruction to detect support for TDX guests in the early boot code (via tdx_early_init()). Since copy_bootdata() is the first user of cc_platform_has() API, detect the TDX guest status before it. Define a synthetic feature flag (X86_FEATURE_TDX_GUEST) and set this bit in a valid TDX guest platform. Signed-off-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com> Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Andi Kleen <ak@linux.intel.com> Reviewed-by: Tony Luck <tony.luck@intel.com> Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Borislav Petkov <bp@suse.de> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20220405232939.73860-2-kirill.shutemov@linux.intel.com
Diffstat (limited to 'arch/x86/kernel/head64.c')
-rw-r--r--arch/x86/kernel/head64.c4
1 files changed, 4 insertions, 0 deletions
diff --git a/arch/x86/kernel/head64.c b/arch/x86/kernel/head64.c
index 4f5ecbbaae77..6dff50c3edd6 100644
--- a/arch/x86/kernel/head64.c
+++ b/arch/x86/kernel/head64.c
@@ -40,6 +40,7 @@
#include <asm/extable.h>
#include <asm/trapnr.h>
#include <asm/sev.h>
+#include <asm/tdx.h>
/*
* Manage page tables very early on.
@@ -514,6 +515,9 @@ asmlinkage __visible void __init x86_64_start_kernel(char * real_mode_data)
idt_setup_early_handler();
+ /* Needed before cc_platform_has() can be used for TDX */
+ tdx_early_init();
+
copy_bootdata(__va(real_mode_data));
/*