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Subject: Re: [PATCH v4] x86/kexec: Carry forward IMA measurement log on kexec
From:   Mimi Zohar <zohar@linux.ibm.com>
To:     Jonathan McDowell <noodles@fb.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        Dave Hansen <dave.hansen@linux.intel.com>,
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        "H. Peter Anvin" <hpa@zytor.com>,
        Dmitry Kasatkin <dmitry.kasatkin@gmail.com>,
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        "linux-integrity@vger.kernel.org" <linux-integrity@vger.kernel.org>,
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        <linux-security-module@vger.kernel.org>
Date:   Wed, 18 May 2022 10:43:32 -0400
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On Thu, 2022-05-12 at 16:25 +0000, Jonathan McDowell wrote:
> On kexec file load Integrity Measurement Architecture (IMA) subsystem
> may verify the IMA signature of the kernel and initramfs, and measure
> it. The command line parameters passed to the kernel in the kexec call
> may also be measured by IMA. A remote attestation service can verify
> a TPM quote based on the TPM event log, the IMA measurement list, and
> the TPM PCR data. This can be achieved only if the IMA measurement log
> is carried over from the current kernel to the next kernel across
> the kexec call.
> 
> 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, so use the setup_data mechanism to pass the IMA buffer to
> the new kernel.
> 
> Signed-off-by: Jonathan McDowell <noodles@fb.com>

Not from using "setup_data" perspective,

	Reviewed-by: Mimi Zohar <zohar@linux.ibm.com>  # IMA function
definitions

thanks,

Mimi