Re: [RFC PATCH v3 08/27] x86/sgx: Initialize virtual EPC driver even when SGX driver is disabled

Kai Huang
2021-02-01T06:43:08Z

On Sat, 30 Jan 2021 16:45:43 +0200 Jarkko Sakkinen wrote:
> On Tue, Jan 26, 2021 at 10:31:00PM +1300, Kai Huang wrote:
> > 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>
> > ---
> > v2->v3:
> >
> > - Changed from sgx_virt_epc_init() to sgx_vepc_init().
> >
> > ---
> > 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 21c2ffa13870..93d249f7bff3 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;
> > @@ -712,7 +713,8 @@ static int __init sgx_init(void)
> > goto err_page_cache;
> > }
> >
> > - ret = sgx_drv_init();
> > + /* Success if the native *or* virtual EPC driver initialized cleanly. */
> > + ret = !!sgx_drv_init() & !!sgx_vepc_init();
>
> If would create more dumb code and just add
>
> ret = sgx_vepc_init()
> if (ret)
> goto err_kthread;

Do you mean you want below?

ret = sgx_drv_init();
ret = sgx_vepc_init();
if (ret)
goto err_kthread;

This was Sean's original code, but Dave didn't like it.

Sean/Dave,

Please let me know which way you prefer.

>
> > if (ret)
> > goto err_kthread;
> >
> > --
> > 2.29.2
> >
>
> /Jarkko
> >