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Date:   Fri, 20 Dec 2019 17:05:37 +0100
From:   Borislav Petkov <bp@alien8.de>
To:     Thomas Garnier <thgarnie@chromium.org>
Cc:     Peter Zijlstra <peterz@infradead.org>,
        Kernel Hardening <kernel-hardening@lists.openwall.com>,
        Kristen Carlson Accardi <kristen@linux.intel.com>,
        Kees Cook <keescook@chromium.org>,
        Andy Lutomirski <luto@kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>,
        "H. Peter Anvin" <hpa@zytor.com>,
        the arch/x86 maintainers <x86@kernel.org>,
        LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v10 04/11] x86/entry/64: Adapt assembly for PIE support
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On Fri, Dec 06, 2019 at 08:35:09AM -0800, Thomas Garnier wrote:
> > Yes, but there it made sense since the PUSH actually created that field
> > of the frame, here it is nonsensical. What this instruction does is put
> > the address of the '1f' label into RDX, which is then stuck into the
> > (R)IP field on the next instruction.
> 
> Got it, make sense. Thanks.
> 
> >
> > > > > +     movq    %rdx, 8(%rsp)   /* Put 1f on return address */

And pls write it out as "put the address of the '1f' label into RDX"
instead of "Put 1f on return address" which could be misunderstood.

Thx.

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette