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Date:   Fri, 12 May 2023 12:40:00 +0100
From:   Matthew Garrett <mjg59@srcf.ucam.org>
To:     Ross Philipson <ross.philipson@oracle.com>
Cc:     linux-kernel@vger.kernel.org, x86@kernel.org,
        linux-integrity@vger.kernel.org, linux-doc@vger.kernel.org,
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        trenchboot-devel@googlegroups.com
Subject: Re: [PATCH v6 11/14] reboot: Secure Launch SEXIT support on reboot
 paths
Message-ID: <20230512114000.GG14461@srcf.ucam.org>
References: <20230504145023.835096-1-ross.philipson@oracle.com>
 <20230504145023.835096-12-ross.philipson@oracle.com>
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On Thu, May 04, 2023 at 02:50:20PM +0000, Ross Philipson wrote:
> If the MLE kernel is being powered off, rebooted or halted,
> then SEXIT must be called. Note that the SEXIT GETSEC leaf
> can only be called after a machine_shutdown() has been done on
> these paths. The machine_shutdown() is not called on a few paths
> like when poweroff action does not have a poweroff callback (into
> ACPI code) or when an emergency reset is done. In these cases,
> just the TXT registers are finalized but SEXIT is skipped.

What are the consequences of SEXIT not being called, and why is it ok to 
skip it in these circumstances?