From 3b863a7db00cefffc15df918a5132c35ea313c27 Mon Sep 17 00:00:00 2001 From: Jarkko Sakkinen Date: Mon, 5 Nov 2018 16:06:06 +0200 Subject: [PATCH] x86/cpu/intel: clean up detect_sgx() flow Signed-off-by: Jarkko Sakkinen --- arch/x86/kernel/cpu/intel.c | 32 ++++++++++++++++++++------------ 1 file changed, 20 insertions(+), 12 deletions(-) diff --git a/arch/x86/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c index bc52c52f7025..8a20a193d399 100644 --- a/arch/x86/kernel/cpu/intel.c +++ b/arch/x86/kernel/cpu/intel.c @@ -598,28 +598,36 @@ static void detect_tme(struct cpuinfo_x86 *c) static void detect_sgx(struct cpuinfo_x86 *c) { - bool unsupported = false; unsigned long long fc; rdmsrl(MSR_IA32_FEATURE_CONTROL, fc); if (!(fc & FEATURE_CONTROL_LOCKED)) { pr_err_once("sgx: IA32_FEATURE_CONTROL MSR is not locked\n"); - unsupported = true; - } else if (!(fc & FEATURE_CONTROL_SGX_ENABLE)) { + goto out_unsupported; + } + + if (!(fc & FEATURE_CONTROL_SGX_ENABLE)) { pr_err_once("sgx: not enabled in IA32_FEATURE_CONTROL MSR\n"); - unsupported = true; - } else if (!cpu_has(c, X86_FEATURE_SGX1)) { + goto out_unsupported; + } + + if (!cpu_has(c, X86_FEATURE_SGX1)) { pr_err_once("sgx: SGX1 instruction set not supported\n"); - unsupported = true; + goto out_unsupported; } - if (unsupported) { - setup_clear_cpu_cap(X86_FEATURE_SGX); - setup_clear_cpu_cap(X86_FEATURE_SGX1); - setup_clear_cpu_cap(X86_FEATURE_SGX2); + if (!(fc & FEATURE_CONTROL_SGX_LE_WR)) { + pr_info_once("sgx: launch control MSRs are not writable\n"); + goto out_msrs_rdonly; } - if (unsupported || !(fc & FEATURE_CONTROL_SGX_LE_WR)) - setup_clear_cpu_cap(X86_FEATURE_SGX_LC); + + return; +out_unsupported: + setup_clear_cpu_cap(X86_FEATURE_SGX); + setup_clear_cpu_cap(X86_FEATURE_SGX1); + setup_clear_cpu_cap(X86_FEATURE_SGX2); +out_msrs_rdonly: + setup_clear_cpu_cap(X86_FEATURE_SGX_LC); } static void init_intel_energy_perf(struct cpuinfo_x86 *c) -- 2.19.1