Use cpuid instead of boot_cpu_has to check cpu features

haitaohuang · haitaohuang · commit ed2c25692996 · 2021-04-16T20:12:10.000Z
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 &lt;4699115+haitaohuang@users.noreply.github.com&gt;
diff --git 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;
 	}

Original file line number	Diff line number	Diff line change
`@@ -313,7 +313,8 @@ static int sgx_drv_probe(struct platform_device *pdev)`
`313`	`313`	`if (boot_cpu_data.x86_vendor != X86_VENDOR_INTEL)`
`314`	`314`	`return -ENODEV;`
`315`	`315`
`316`		`- if (!boot_cpu_has(X86_FEATURE_SGX)) {`
	`316`	`+ cpuid(7, &eax, &ebx, &ecx, &edx);`
	`317`	`+ if(!((ebx >> 2) & 0x1)){`
`317`	`318`	`pr_err("intel_sgx: the CPU is missing SGX\n");`
`318`	`319`	`return -ENODEV;`
`319`	`320`	`}`