[RFC PATCH v2 07/26] x86/sgx: Initialize virtual EPC driver even when SGX driver is disabled

[Kai Huang <kai.huang@intel.com>]

Modify sgx_init() to always try to initialize the virtual EPC driver,
even if the bare-metal SGX driver is disabled.  The bare-metal driver
might be disabled if SGX Launch Control is in locked mode, or not
supported in the hardware at all.  This allows (non-Linux) guests that
support non-LC configurations to use SGX.

Signed-off-by: Kai Huang <kai.huang@intel.com>
---
 arch/x86/kernel/cpu/sgx/main.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/arch/x86/kernel/cpu/sgx/main.c b/arch/x86/kernel/cpu/sgx/main.c
index 5e20b42f2639..bdda631c975b 100644
--- a/arch/x86/kernel/cpu/sgx/main.c
+++ b/arch/x86/kernel/cpu/sgx/main.c
@@ -12,6 +12,7 @@
 #include "driver.h"
 #include "encl.h"
 #include "encls.h"
+#include "virt.h"
 
 struct sgx_epc_section sgx_epc_sections[SGX_MAX_EPC_SECTIONS];
 static int sgx_nr_epc_sections;
@@ -710,7 +711,8 @@ static void __init sgx_init(void)
 	if (!sgx_page_reclaimer_init())
 		goto err_page_cache;
 
-	ret = sgx_drv_init();
+	/* Success if the native *or* virtual EPC driver initialized cleanly. */
+	ret = !!sgx_drv_init() & !!sgx_virt_epc_init();
 	if (ret)
 		goto err_kthread;
 
-- 
2.29.2