Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]


Groups > linux.kernel > #1723796

Re: [PATCH v8 02/28] x86/boot: Relocate definition of the initial state of CR0

From Ricardo Neri <ricardo.neri-calderon@linux.intel.com>
Newsgroups linux.kernel
Subject Re: [PATCH v8 02/28] x86/boot: Relocate definition of the initial state of CR0
Date 2017-08-31 06:10 +0200
Message-ID <ukoXL-Lg-7@gated-at.bofh.it> (permalink)
References <ufZOh-2z5-3@gated-at.bofh.it> <ufZOh-2z5-1@gated-at.bofh.it> <uiqU3-71g-31@gated-at.bofh.it>
Organization linux.* mail to news gateway

Show all headers | View raw


On Fri, 2017-08-25 at 19:41 +0200, Borislav Petkov wrote:

Thanks Borislav for your feedback!

> On Fri, Aug 18, 2017 at 05:27:43PM -0700, Ricardo Neri wrote:
> > Both head_32.S and head_64.S utilize the same value to initialize the
> > control register CR0. Also, other parts of the kernel might want to access
> > to this initial definition (e.g., emulation code for User-Mode Instruction
> 
> s/to //
> 
> > Prevention uses this state to provide a sane dummy value for CR0 when

I'll make this change.

> > emulating the smsw instruction). Thus, relocate this definition to a
> > header file from which it can be conveniently accessed.
> > 
> > Cc: Andrew Morton <akpm@linux-foundation.org>
> > Cc: Andy Lutomirski <luto@amacapital.net>
> > Cc: Andy Lutomirski <luto@kernel.org>
> > Cc: Borislav Petkov <bp@alien8.de>
> > Cc: Brian Gerst <brgerst@gmail.com>
> > Cc: Dave Hansen <dave.hansen@intel.com>
> > Cc: Denys Vlasenko <dvlasenk@redhat.com>
> > Cc: H. Peter Anvin <hpa@zytor.com>
> > Cc: Josh Poimboeuf <jpoimboe@redhat.com>
> > Cc: Linus Torvalds <torvalds@linux-foundation.org>
> > Cc: Peter Zijlstra <peterz@infradead.org>
> > Cc: Thomas Gleixner <tglx@linutronix.de>
> > Cc: linux-arch@vger.kernel.org
> > Cc: linux-mm@kvack.org
> > Suggested-by: Borislav Petkov <bp@alien8.de>
> > Signed-off-by: Ricardo Neri <ricardo.neri-calderon@linux.intel.com>
> > ---
> >  arch/x86/include/uapi/asm/processor-flags.h | 6 ++++++
> >  arch/x86/kernel/head_32.S                   | 3 ---
> >  arch/x86/kernel/head_64.S                   | 3 ---
> >  3 files changed, 6 insertions(+), 6 deletions(-)
> > 
> > diff --git a/arch/x86/include/uapi/asm/processor-flags.h b/arch/x86/include/uapi/asm/processor-flags.h
> > index 185f3d10c194..aae1f2aa7563 100644
> > --- a/arch/x86/include/uapi/asm/processor-flags.h
> > +++ b/arch/x86/include/uapi/asm/processor-flags.h
> > @@ -151,5 +151,11 @@
> >  #define CX86_ARR_BASE	0xc4
> >  #define CX86_RCR_BASE	0xdc
> >  
> > +/*
> > + * Initial state of CR0 for head_32/64.S
> > + */
> 
> No need for that comment.
> 
> With the minor nitpicks addressed, you can add:
> 
> Reviewed-by: Borislav Petkov <bp@suse.de>

Thank you! Is it necessary for me to submit a v9 with these updates?
Perhaps I can make these updates in branch for the maintainers to pull
when/if this series is ack'ed.

Thanks and BR,
Ricardo

Back to linux.kernel | Previous | NextPrevious in thread | Next in thread | Find similar | Unroll thread


Thread

Re: [PATCH v8 02/28] x86/boot: Relocate definition of the initial  state of CR0 Borislav Petkov <bp@suse.de> - 2017-08-25 19:50 +0200
  Re: [PATCH v8 02/28] x86/boot: Relocate definition of the initial  state of CR0 Ricardo Neri <ricardo.neri-calderon@linux.intel.com> - 2017-08-31 06:10 +0200
    Re: [PATCH v8 02/28] x86/boot: Relocate definition of the initial  state of CR0 Borislav Petkov <bp@suse.de> - 2017-08-31 12:00 +0200
      Re: [PATCH v8 02/28] x86/boot: Relocate definition of the initial  state of CR0 Ricardo Neri <ricardo.neri-calderon@linux.intel.com> - 2017-09-02 19:40 +0200

csiph-web