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Message-ID: <d31e8276-9303-fff8-427f-afc859131202@linux.ibm.com>
Date:   Mon, 31 Jan 2022 17:28:44 -0500
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Subject: Re: [PATCH v9 04/23] securityfs: Extend securityfs with namespacing
 support
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To:     Mimi Zohar <zohar@linux.ibm.com>,
        Stefan Berger <stefanb@linux.vnet.ibm.com>,
        linux-integrity@vger.kernel.org
Cc:     serge@hallyn.com, christian.brauner@ubuntu.com,
        containers@lists.linux.dev, dmitry.kasatkin@gmail.com,
        ebiederm@xmission.com, krzysztof.struczynski@huawei.com,
        roberto.sassu@huawei.com, mpeters@redhat.com, lhinds@redhat.com,
        lsturman@redhat.com, puiterwi@redhat.com, jejb@linux.ibm.com,
        jamjoom@us.ibm.com, linux-kernel@vger.kernel.org,
        paul@paul-moore.com, rgb@redhat.com,
        linux-security-module@vger.kernel.org, jmorris@namei.org,
        James Bottomley <James.Bottomley@HansenPartnership.com>,
        Christian Brauner <brauner@kernel.org>
References: <20220125224645.79319-1-stefanb@linux.vnet.ibm.com>
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From:   Stefan Berger <stefanb@linux.ibm.com>
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On 1/27/22 11:53, Mimi Zohar wrote:
> On Tue, 2022-01-25 at 17:46 -0500, Stefan Berger wrote:
>> From: Stefan Berger <stefanb@linux.ibm.com>
>>
>> Enable multiple instances of securityfs by keying each instance with a
>> pointer to the user namespace it belongs to.
>>
>> Since we do not need the pinning of the filesystem for the virtualization
>> case, limit the usage of simple_pin_fs() and simpe_release_fs() to the
>> case when the init_user_ns is active. This simplifies the cleanup for the
>> virtualization case where usage of securityfs_remove() to free dentries
>> is not needed anymore.
> Could you add a sentence here explaining why securityfs_remove() isn't
> needed in the virtualization case?

At this point the reason is that simple_pin_fs() is not used for the 
virtualization case.

Maybe it should say: ... to free dentries is *therefore* not needed anymore.

    Stefan