On Fri, Mar 05, 2021 at 06:29:57PM +0100, Borislav Petkov wrote:
> On Mon, Mar 01, 2021 at 10:45:02PM +1300, Kai Huang wrote:
> > From: Sean Christopherson <sean.j.christopherson@xxxxxxxxx>
> >
> > The kernel will currently disable all SGX support if the hardware does
> > not support launch control. Make it more permissive to allow SGX
> > virtualization on systems without Launch Control support. This will
> > allow KVM to expose SGX to guests that have less-strict requirements on
> > the availability of flexible launch control.
> >
> > Improve error message to distinguish between three cases. There are two
> > cases where SGX support is completely disabled:
> > 1) SGX has been disabled completely by the BIOS
> > 2) SGX LC is locked by the BIOS. Bare-metal support is disabled because
> > of LC unavailability. SGX virtualization is unavailable (because of
> > Kconfig).
> > One where it is partially available:
> > 3) SGX LC is locked by the BIOS. Bare-metal support is disabled because
> > of LC unavailability. SGX virtualization is supported.
> >
> > Signed-off-by: Sean Christopherson <sean.j.christopherson@xxxxxxxxx>
> > Co-developed-by: Kai Huang <kai.huang@xxxxxxxxx>
> > Acked-by: Dave Hansen <dave.hansen@xxxxxxxxx>
> > Signed-off-by: Kai Huang <kai.huang@xxxxxxxxx>
> > ---
> > arch/x86/kernel/cpu/feat_ctl.c | 57 ++++++++++++++++++++++++++--------
> > 1 file changed, 44 insertions(+), 13 deletions(-)
> >
> > diff --git a/arch/x86/kernel/cpu/feat_ctl.c b/arch/x86/kernel/cpu/feat_ctl.c
> > index 27533a6e04fa..96c370284913 100644
> > --- a/arch/x86/kernel/cpu/feat_ctl.c
> > +++ b/arch/x86/kernel/cpu/feat_ctl.c
> > @@ -105,7 +105,8 @@ early_param("nosgx", nosgx);
> > void init_ia32_feat_ctl(struct cpuinfo_x86 *c)
> > {
> > bool tboot = tboot_enabled();
> > - bool enable_sgx;
> > + bool enable_sgx_any, enable_sgx_kvm, enable_sgx_driver;
> > + bool enable_vmx;
> > u64 msr;
>
> The preferred ordering of variable declarations at the beginning of a
> function is reverse fir tree order::
>
> struct long_struct_name *descriptive_name;
> unsigned long foo, bar;
> unsigned int tmp;
> int ret;
IMHO here declaring separate lines would make also sense, given
how long the local variable names are.
/Jarkko
