34988d2e0c
[ Upstream commit 65be5c95d08eedda570a6c888a12384c77fe7614 ] The kernel requires X86_FEATURE_SGX_LC to be able to create SGX enclaves, not just X86_FEATURE_SGX. There is quite a number of hardware which has X86_FEATURE_SGX but not X86_FEATURE_SGX_LC. A kernel running on such hardware does not create the /dev/sgx_enclave file and does so silently. Explicitly warn if X86_FEATURE_SGX_LC is not enabled to properly notify users that the kernel disabled the SGX driver. The X86_FEATURE_SGX_LC, a.k.a. SGX Launch Control, is a CPU feature that enables LE (Launch Enclave) hash MSRs to be writable (with additional opt-in required in the 'feature control' MSR) when running enclaves, i.e. using a custom root key rather than the Intel proprietary key for enclave signing. I've hit this issue myself and have spent some time researching where my /dev/sgx_enclave file went on SGX-enabled hardware. Related links: https://github.com/intel/linux-sgx/issues/837 https://patchwork.kernel.org/project/platform-driver-x86/patch/20180827185507.17087-3-jarkko.sakkinen@linux.intel.com/ [ mingo: Made the error message a bit more verbose, and added other cases where the kernel fails to create the /dev/sgx_enclave device node. ] Signed-off-by: Vladis Dronov <vdronov@redhat.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Kai Huang <kai.huang@intel.com> Cc: Jarkko Sakkinen <jarkko@kernel.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Sean Christopherson <sean.j.christopherson@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: https://lore.kernel.org/r/20250309172215.21777-2-vdronov@redhat.com Signed-off-by: Sasha Levin <sashal@kernel.org> |
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| .. | ||
| mce | ||
| microcode | ||
| mtrr | ||
| resctrl | ||
| sgx | ||
| .gitignore | ||
| acrn.c | ||
| amd.c | ||
| aperfmperf.c | ||
| bugs.c | ||
| cacheinfo.c | ||
| centaur.c | ||
| common.c | ||
| cpu.h | ||
| cpuid-deps.c | ||
| cyrix.c | ||
| feat_ctl.c | ||
| hygon.c | ||
| hypervisor.c | ||
| intel_epb.c | ||
| intel_pconfig.c | ||
| intel.c | ||
| Makefile | ||
| match.c | ||
| mkcapflags.sh | ||
| mshyperv.c | ||
| perfctr-watchdog.c | ||
| powerflags.c | ||
| proc.c | ||
| rdrand.c | ||
| scattered.c | ||
| topology.c | ||
| transmeta.c | ||
| tsx.c | ||
| umc.c | ||
| umwait.c | ||
| vmware.c | ||
| vortex.c | ||
| zhaoxin.c | ||