3f1a9bc5 - x86/build: Use obj-y to descend into arch/x86/virt/

Sat, 30 Mar 2024 06:05:54 +0000

x86/build: Use obj-y to descend into arch/x86/virt/Commit c33621b4c5ad ("x86/virt/tdx: Wire up basic SEAMCALL functions")introduced a new instance of core-y instead of the standardized obj-ysyntax.X86 Makefiles descend into subdirectories of arch/x86/virt inconsistently;into arch/x86/virt/ via core-y defined in arch/x86/Makefile, but intoarch/x86/virt/svm/ via obj-y defined in arch/x86/Kbuild.This is problematic when you build a single object in parallel becausemultiple threads attempt to build the same file. $ make -j$(nproc) arch/x86/virt/vmx/tdx/seamcall.o [ snip ] AS arch/x86/virt/vmx/tdx/seamcall.o AS arch/x86/virt/vmx/tdx/seamcall.o fixdep: error opening file: arch/x86/virt/vmx/tdx/.seamcall.o.d: No such file or directory make[4]: *** [scripts/Makefile.build:362: arch/x86/virt/vmx/tdx/seamcall.o] Error 2Use the obj-y syntax, as it works correctly.Signed-off-by: Masahiro Yamada Signed-off-by: Ingo Molnar Link: https://lore.kernel.org/r/20240330060554.18524-1-masahiroy@kernel.org List of files: /linux-6.15/arch/x86/virt/Makefile

c33621b4 - x86/virt/tdx: Wire up basic SEAMCALL functions

Tue, 15 Aug 2023 11:02:04 +0000

x86/virt/tdx: Wire up basic SEAMCALL functionsIntel Trust Domain Extensions (TDX) protects guest VMs from malicioushost and certain physical attacks. A CPU-attested software modulecalled 'the TDX module' runs inside a new isolated memory range as atrusted hypervisor to manage and run protected VMs.TDX introduces a new CPU mode: Secure Arbitration Mode (SEAM). Thismode runs only the TDX module itself or other code to load the TDXmodule.The host kernel communicates with SEAM software via a new SEAMCALLinstruction. This is conceptually similar to a guest->host hypercall,except it is made from the host to SEAM software instead. The TDXmodule establishes a new SEAMCALL ABI which allows the host toinitialize the module and to manage VMs.The SEAMCALL ABI is very similar to the TDCALL ABI and leverages muchTDCALL infrastructure. Wire up basic functions to make SEAMCALLs forthe basic support of running TDX guests: __seamcall(), __seamcall_ret(),and __seamcall_saved_ret() for TDH.VP.ENTER. All SEAMCALLs involved inthe basic TDX support don't use "callee-saved" registers as input andoutput, except the TDH.VP.ENTER.To start to support TDX, create a new arch/x86/virt/vmx/tdx/tdx.c forTDX host kernel support. Add a new Kconfig option CONFIG_INTEL_TDX_HOSTto opt-in TDX host kernel support (to distinguish with TDX guest kernelsupport). So far only KVM uses TDX. Make the new config option dependon 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 List of files: /linux-6.15/arch/x86/virt/Makefile

Changes in Makefile

3f1a9bc5 - x86/build: Use obj-y to descend into arch/x86/virt/

c33621b4 - x86/virt/tdx: Wire up basic SEAMCALL functions