Messages in this thread | | | Date | Wed, 13 Oct 2021 12:42:51 -0700 | From | Josh Poimboeuf <> | Subject | Re: [PATCH v10 03/11] x86/cpufeatures: Add TDX Guest CPU feature |
| |
On Wed, Oct 13, 2021 at 10:18:18AM +0200, 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. > */
But there are no actual TDX cmdline options in this patch set, which is why I originally asked for clarification in the comment.
> > + 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.
I disagree, this prevents confusion and misuse by making it clear that the scope of the static variable is limited to this function.
-- Josh
| |