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From:   Matthew Garrett <mjg59@google.com>
Date:   Thu, 7 Mar 2019 14:50:17 -0800
Message-ID: <CACdnJusiLSCyqx7NX5bkpFr2N5YjBt_h3miOgkbey-Zndc3+Kg@mail.gmail.com>
Subject: Re: [PATCH 3/3] x86/ima: retry detecting secure boot mode
To:     Mimi Zohar <zohar@linux.ibm.com>
Cc:     Justin Forbes <jforbes@redhat.com>,
        linux-integrity <linux-integrity@vger.kernel.org>,
        LSM List <linux-security-module@vger.kernel.org>,
        linux-efi <linux-efi@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        David Howells <dhowells@redhat.com>,
        Seth Forshee <seth.forshee@canonical.com>,
        kexec@lists.infradead.org, Nayna Jain <nayna@linux.ibm.com>
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On Thu, Mar 7, 2019 at 2:48 PM Mimi Zohar <zohar@linux.ibm.com> wrote:
> I added this last attempt because I'm seeing this on my laptop, with
> some older, buggy firmware.

Is the issue that it gives incorrect results on the first read, or is
the issue that it gives incorrect results before ExitBootServices() is
called? If the former then we should read twice in the boot stub, if
the latter then we should figure out a way to do this immediately
after ExitBootServices() instead.