From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Howells <dhowells@redhat.com>
Subject: Re: [PATCH] xfs: publish UUID in struct super_block
Date: Thu, 27 Apr 2017 13:57:01 +0100
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References: <20170427075946.GA22284@lst.de> <1493279911-2936-1-git-send-email-amir73il@gmail.com>
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To: Christoph Hellwig <hch@lst.de>
Cc: dhowells@redhat.com, Amir Goldstein <amir73il@gmail.com>, "Darrick J . Wong" <darrick.wong@oracle.com>, Miklos Szeredi <miklos@szeredi.hu>, Vivek Goyal <vgoyal@redhat.com>, Al Viro <viro@zeniv.linux.org.uk>, linux-xfs@vger.kernel.org, linux-unionfs@vger.kernel.org, linux-fsdevel@vger.kernel.org

Christoph Hellwig <hch@lst.de> wrote:

> Until we have a flag in the superblock that a given fs fills out s_uuid
> no one can rely on it.  So please add the infrastructure that consumers
> can actually make use of it while you're at it.

Can't you just look at whether s_uuid is NULL or not?

David