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From: David Howells <dhowells@redhat.com>
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To: Andy Lutomirski <luto@amacapital.net>
Cc: dhowells@redhat.com, Al Viro <viro@zeniv.linux.org.uk>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Linux FS Devel <linux-fsdevel@vger.kernel.org>,
        Linux API <linux-api@vger.kernel.org>
Subject: Re: [git pull] new mount API
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Date: Fri, 24 Aug 2018 01:08:36 +0100
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Andy Lutomirski <luto@amacapital.net> wrote:

> Has anything been done to ensure that the behavior when doing
> FSCONFIG_CMD_CREATE against an already-mounted block device is
> reasonable?

For the moment, I've left it as the same behaviour as for mount(2) since
mount(2) now uses the same mechanism internally and we aren't permitted to
break userspace.

I would like to add at least one flag to stipulate that, in the case of an
incompatible collision, you can get a failure - but defining what is meant by
incompatible isn't necessarily trivial, and would vary by filesystem *and* the
LSM.

However, I don't want to start reengineering everything this close to the
merge window and we don't really need it immediately.

David