From c33621b4c5ad5b6b8b245754013cc506f9ded2b8 Mon Sep 17 00:00:00 2001 From: Kai Huang Date: Tue, 15 Aug 2023 23:02:04 +1200 Subject: x86/virt/tdx: Wire up basic SEAMCALL functions Intel Trust Domain Extensions (TDX) protects guest VMs from malicious host and certain physical attacks. A CPU-attested software module called 'the TDX module' runs inside a new isolated memory range as a trusted hypervisor to manage and run protected VMs. TDX introduces a new CPU mode: Secure Arbitration Mode (SEAM). This mode runs only the TDX module itself or other code to load the TDX module. The host kernel communicates with SEAM software via a new SEAMCALL instruction. This is conceptually similar to a guest->host hypercall, except it is made from the host to SEAM software instead. The TDX module establishes a new SEAMCALL ABI which allows the host to initialize the module and to manage VMs. The SEAMCALL ABI is very similar to the TDCALL ABI and leverages much TDCALL infrastructure. Wire up basic functions to make SEAMCALLs for the basic support of running TDX guests: __seamcall(), __seamcall_ret(), and __seamcall_saved_ret() for TDH.VP.ENTER. All SEAMCALLs involved in the basic TDX support don't use "callee-saved" registers as input and output, except the TDH.VP.ENTER. To start to support TDX, create a new arch/x86/virt/vmx/tdx/tdx.c for TDX host kernel support. Add a new Kconfig option CONFIG_INTEL_TDX_HOST to opt-in TDX host kernel support (to distinguish with TDX guest kernel support). So far only KVM uses TDX. Make the new config option depend on KVM_INTEL. Signed-off-by: Kai Huang Signed-off-by: Dave Hansen Reviewed-by: Kirill A. Shutemov Acked-by: Peter Zijlstra (Intel) Tested-by: Isaku Yamahata Link: https://lore.kernel.org/all/4db7c3fc085e6af12acc2932294254ddb3d320b3.1692096753.git.kai.huang%40intel.com --- arch/x86/Makefile | 2 ++ 1 file changed, 2 insertions(+) (limited to 'arch/x86/Makefile') diff --git a/arch/x86/Makefile b/arch/x86/Makefile index 5bfe5caaa444..d43981a1fd1d 100644 --- a/arch/x86/Makefile +++ b/arch/x86/Makefile @@ -252,6 +252,8 @@ archheaders: libs-y += arch/x86/lib/ +core-y += arch/x86/virt/ + # drivers-y are linked after core-y drivers-$(CONFIG_MATH_EMULATION) += arch/x86/math-emu/ drivers-$(CONFIG_PCI) += arch/x86/pci/ -- cgit