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Date:   Tue, 3 Jul 2018 22:58:26 +0100
From:   Al Viro <viro@ZenIV.linux.org.uk>
To:     David Howells <dhowells@redhat.com>
Cc:     Eric Biggers <ebiggers3@gmail.com>, linux-fsdevel@vger.kernel.org,
        linux-kernel@vger.kernel.org, linux-afs@lists.infradead.org
Subject: Re: [PATCH 10/32] VFS: Implement a filesystem superblock
 creation/configuration context [ver #8]
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On Tue, Jul 03, 2018 at 10:53:22PM +0100, David Howells wrote:
> -				if (s) {
> -					up_write(&s->s_umount);
> +				if (s)
>  					destroy_unused_super(s);

static void destroy_unused_super(struct super_block *s)
{
        if (!s)
                return;
	...
}

IOW, all of those should be unconditional.