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From: Andy Lutomirski <luto@kernel.org>
Date: Thu, 31 May 2018 13:38:17 -0700
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Subject: Re: [PATCH V2 02/15] x86/fsgsbase/64: Make ptrace read FS/GS base accurately
To: "H. Peter Anvin" <hpa@zytor.com>
Cc: Andrew Lutomirski <luto@kernel.org>,
        "Bae, Chang Seok" <chang.seok.bae@intel.com>,
        Thomas Gleixner <tglx@linutronix.de>, Ingo Molnar <mingo@kernel.org>,
        Andi Kleen <ak@linux.intel.com>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        "Metzger, Markus T" <markus.t.metzger@intel.com>,
        "Ravi V. Shankar" <ravi.v.shankar@intel.com>,
        LKML <linux-kernel@vger.kernel.org>
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On Thu, May 31, 2018 at 1:31 PM <hpa@zytor.com> wrote:
>
> On May 31, 2018 1:14:59 PM PDT, Andy Lutomirski <luto@kernel.org> wrote:
> >On Thu, May 31, 2018 at 10:58 AM Chang S. Bae
> ><chang.seok.bae@intel.com> wrote:
> >>
> >> From: Andy Lutomirski <luto@kernel.org>
> >>
> >> ptrace can read FS/GS base using the register access API
> >> (PTRACE_PEEKUSER, etc) or PTRACE_ARCH_PRCTL.  Make both of these
> >> mechanisms return the actual FS/GS base.
> >>
> >> This will improve debuggability by providing the correct information
> >> to ptracer (GDB and etc).
> >
> >LGTM.
>
> LGTM?

Looks good to me.