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Date:   Tue, 8 Jan 2019 19:57:51 +0100
From:   Peter Zijlstra <peterz@infradead.org>
To:     Andi Kleen <ak@linux.intel.com>
Cc:     Adrian Hunter <adrian.hunter@intel.com>,
        Nadav Amit <namit@vmware.com>, Ingo Molnar <mingo@redhat.com>,
        Andy Lutomirski <luto@kernel.org>,
        Josh Poimboeuf <jpoimboe@redhat.com>,
        Edward Cree <ecree@solarflare.com>,
        "H . Peter Anvin" <hpa@zytor.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        LKML <linux-kernel@vger.kernel.org>,
        Nadav Amit <nadav.amit@gmail.com>, X86 ML <x86@kernel.org>,
        Paolo Abeni <pabeni@redhat.com>,
        Borislav Petkov <bp@alien8.de>,
        David Woodhouse <dwmw@amazon.co.uk>,
        Alexander Shishkin <alexander.shishkin@linux.intel.com>,
        songliubraving@fb.com
Subject: Re: [RFC v2 0/6] x86: dynamic indirect branch promotion
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On Tue, Jan 08, 2019 at 09:27:21AM -0800, Andi Kleen wrote:
> It doesn't work when the code is modified in place, like the
> patch in the $SUBJECT.

For in-place modification a-la jump_label / static_call etc. we can
'trivially' log the new instruction and the decoder can do matching
in-place kcore adjustments.