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Date:   Mon, 3 Jul 2023 15:48:03 -0700
From:   Mike Kravetz <mike.kravetz@oracle.com>
To:     "Darrick J. Wong" <djwong@kernel.org>
Cc:     Thomas =?iso-8859-1?Q?Wei=DFschuh?= <linux@weissschuh.net>,
        Alexander Viro <viro@zeniv.linux.org.uk>,
        Christian Brauner <brauner@kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-mm@kvack.org, Willy Tarreau <w@lwt.eu>,
        Zhangjin Wu <falcon@tinylab.org>
Subject: Re: [PATCH] mm: make MEMFD_CREATE into a selectable config option
Message-ID: <20230703224803.GF4378@monkey>
References: <20230630-config-memfd-v1-1-9acc3ae38b5a@weissschuh.net>
 <20230630153236.GD11423@frogsfrogsfrogs>
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On 06/30/23 08:32, Darrick J. Wong wrote:
> On Fri, Jun 30, 2023 at 11:08:53AM +0200, Thomas Wei?schuh wrote:
> > The memfd_create() syscall, enabled by CONFIG_MEMFD_CREATE, is useful on
> > its own even when not required by CONFIG_TMPFS or CONFIG_HUGETLBFS.
> 
> If you don't have tmpfs or hugetlbfs enabled, then what fs ends up
> backing the file returned by memfd_create()?  ramfs?
> 
> (Not an objection, I'm just curious...)
> 

It looks like shmem/tmpfs falls back to ramfs?

-- 
Mike Kravetz