From ed2c256929962db1a8805db53bed09bb8f2f4de3 Mon Sep 17 00:00:00 2001
From: Haitao Huang <4699115+haitaohuang@users.noreply.github.com>
Date: Fri, 16 Apr 2021 20:12:10 +0000
Subject: [PATCH] Use cpuid instead of boot_cpu_has to check cpu features

For non-FLC platforms, Linux kernel 5.11 or above disables sgx feature flag
so boot_cpu_has is not usable.

Signed-off-by: Haitao Huang <4699115+haitaohuang@users.noreply.github.com>
---
 sgx_main.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/sgx_main.c b/sgx_main.c
index 4ff4e2b..ca52821 100644
--- a/sgx_main.c
+++ b/sgx_main.c
@@ -313,7 +313,8 @@ static int sgx_drv_probe(struct platform_device *pdev)
 	if (boot_cpu_data.x86_vendor != X86_VENDOR_INTEL)
 		return -ENODEV;
 
-	if (!boot_cpu_has(X86_FEATURE_SGX)) {
+	cpuid(7, &eax, &ebx, &ecx, &edx);
+	if(!((ebx >> 2) & 0x1)){
 		pr_err("intel_sgx: the CPU is missing SGX\n");
 		return -ENODEV;
 	}