Re: [PATCH v10 03/11] x86/cpufeatures: Add TDX Guest CPU feature

[Sathyanarayanan Kuppuswamy]

On 10/13/21 1:18 AM, Borislav Petkov wrote:
> On Fri, Oct 08, 2021 at 10:37:39PM -0700, Kuppuswamy Sathyanarayanan wrote:
> > @@ -500,6 +501,14 @@ asmlinkage __visible void __init x86_64_start_kernel(char * real_mode_data)
> >   
> >   	copy_bootdata(__va(real_mode_data));
> >   
> > +	/*
> > +	 * A future dependency on cmdline parameters is expected (for
> > +	 * adding debug options). So the order of calling it should be
> > +	 * after copy_bootdata() (in which command line parameter is
> > +	 * initialized).
> > +	 */
> Plain and simple:
>
>          /*
>           * Keep this after copy_bootdata() so that TDX cmdline options can take
>           * effect.
>           */
ok. I will fix this in next version.
> > +	tdx_early_init();
> > +
> >   	/*
> >   	 * Load microcode early on BSP.
> >   	 */
> > diff --git a/arch/x86/kernel/tdx.c b/arch/x86/kernel/tdx.c
> > new file mode 100644
> > index 000000000000..88bf12788684
> > --- /dev/null
> > +++ b/arch/x86/kernel/tdx.c
> > @@ -0,0 +1,38 @@
> > +// SPDX-License-Identifier: GPL-2.0
> > +/* Copyright (C) 2020 Intel Corporation */
> > +
> > +#undef pr_fmt
> > +#define pr_fmt(fmt)     "tdx: " fmt
> > +
> > +#include <asm/tdx.h>
> > +
> > +bool is_tdx_guest(void)
> > +{
> > +	static int tdx_guest = -1;
> Put that one at the top of the file because such static variables do not
> belong among the automatic function vars.
ok. I will fix this in next version.
> Thx.
--
Sathyanarayanan Kuppuswamy
Linux Kernel Developer