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From:   Linus Torvalds <torvalds@linux-foundation.org>
Date:   Thu, 20 Feb 2020 15:00:13 -0800
Message-ID: <CAHk-=whPwMTTaGtphubBXeiKitKigutddx9Fcp4Sf1sw4tpyeA@mail.gmail.com>
Subject: Re: [PATCH 4/7] proc: Use d_invalidate in proc_prune_siblings_dcache
To:     Al Viro <viro@zeniv.linux.org.uk>
Cc:     "Eric W. Biederman" <ebiederm@xmission.com>,
        LKML <linux-kernel@vger.kernel.org>,
        Kernel Hardening <kernel-hardening@lists.openwall.com>,
        Linux API <linux-api@vger.kernel.org>,
        Linux FS Devel <linux-fsdevel@vger.kernel.org>,
        Linux Security Module <linux-security-module@vger.kernel.org>,
        Akinobu Mita <akinobu.mita@gmail.com>,
        Alexey Dobriyan <adobriyan@gmail.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Andy Lutomirski <luto@kernel.org>,
        Daniel Micay <danielmicay@gmail.com>,
        Djalal Harouni <tixxdz@gmail.com>,
        "Dmitry V . Levin" <ldv@altlinux.org>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Ingo Molnar <mingo@kernel.org>,
        "J . Bruce Fields" <bfields@fieldses.org>,
        Jeff Layton <jlayton@poochiereds.net>,
        Jonathan Corbet <corbet@lwn.net>,
        Kees Cook <keescook@chromium.org>,
        Oleg Nesterov <oleg@redhat.com>,
        Solar Designer <solar@openwall.com>
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On Thu, Feb 20, 2020 at 2:54 PM Al Viro <viro@zeniv.linux.org.uk> wrote:
>
> s/no inode.*/it's a directory inode./

That actually makes my worry go away too. We don't allow aliases for
directory inodes, iirc.

So then it doesn't depend on some /proc implementation issue any more,
then it's fundamental that there's only one dentry.

            Linus