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From:   Raul Rangel <rrangel@chromium.org>
Date:   Wed, 25 Oct 2023 08:59:13 -0600
Message-ID: <CAHQZ30BSD2c4WwUTARx9OeqTjusgq7te8OzwdUi6Qk+L=9vSgA@mail.gmail.com>
Subject: Re: [PATCH v3] ima: detect changes to the backing overlay file
To:     Mimi Zohar <zohar@linux.ibm.com>
Cc:     linux-integrity@vger.kernel.org, linux-kernel@vger.kernel.org,
        Eric Snowberg <eric.snowberg@oracle.com>,
        Amir Goldstein <amir73il@gmail.com>
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On Wed, Oct 25, 2023 at 8:39=E2=80=AFAM Mimi Zohar <zohar@linux.ibm.com> wr=
ote:
> +               if (!IS_I_VERSION(backing_inode) ||
> +                   backing_inode->i_sb->s_dev !=3D iint->real_dev ||
> +                   backing_inode->i_ino !=3D iint->real_ino ||
> +                   !inode_eq_iversion(backing_inode, iint->version)) {
> +                       iint->flags &=3D ~IMA_DONE_MASK;
> +                       iint->measured_pcrs =3D 0;
> +               }
> +       }
> +
Does this mean I need to mount ext4 with `-o iversion`? Or has it been
enabled by default?

I can test this patch out sometime this week and verify it fixes the
performance regression.

Thanks!