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From:   Jonathan McDowell <noodles@fb.com>
To:     Boris Petkov <bp@alien8.de>
CC:     Thomas Gleixner <tglx@linutronix.de>,
        James Morris <jmorris@namei.org>,
        Ingo Molnar <mingo@redhat.com>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        "H. Peter Anvin" <hpa@zytor.com>,
        Dmitry Kasatkin <dmitry.kasatkin@gmail.com>,
        "x86@kernel.org" <x86@kernel.org>,
        Mimi Zohar <zohar@linux.ibm.com>,
        "Serge E. Hallyn" <serge@hallyn.com>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "linux-integrity@vger.kernel.org" <linux-integrity@vger.kernel.org>,
        "linux-security-module@vger.kernel.org" 
        <linux-security-module@vger.kernel.org>
Subject: Re: [PATCH v2] Carry forward IMA measurement log on kexec on x86_64
Thread-Topic: [PATCH v2] Carry forward IMA measurement log on kexec on x86_64
Thread-Index: AQHYWY4yqojcPM99qUKBDg6v3vLzMa0WbyIAgAAMsgCAAGptgA==
Date:   Mon, 9 May 2022 17:46:22 +0000
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On Mon, May 09, 2022 at 11:25:22AM +0000, Boris Petkov wrote:
> On May 9, 2022 10:40:01 AM UTC, Jonathan McDowell <noodles@fb.com> wrote:
> >> powerpc and ARM64 both achieve this using device tree with a
> >> "linux,ima-kexec-buffer" node. x86 platforms generally don't make use of
> >> device tree
> 
> What's wrong with making x86 use the same devicetree node(s)?

Device tree on x86 doesn't seem to be a thing; none of the distros I
regularly use enable CONFIG_OF for x86, I can only find 2 32-bit x86
platforms that actually select it and none of the plumbing for kexec on
x86 ties in device tree. I agree for platforms that make active use of
device tree that's the appropriate path, but it doesn't seem to be the
case for x86.

J.