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From:   Miklos Szeredi <miklos@szeredi.hu>
Date:   Wed, 5 Aug 2020 13:56:01 +0200
Message-ID: <CAJfpegvT-UznTC5CT1kjVF=Gr+DfTJXKj5CEkP67G9zFhjLMEg@mail.gmail.com>
Subject: Re: [PATCH 13/17] watch_queue: Implement mount topology and attribute
 change notifications [ver #5]
To:     Ian Kent <raven@themaw.net>
Cc:     David Howells <dhowells@redhat.com>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Al Viro <viro@zeniv.linux.org.uk>,
        Casey Schaufler <casey@schaufler-ca.com>,
        Stephen Smalley <sds@tycho.nsa.gov>,
        Nicolas Dichtel <nicolas.dichtel@6wind.com>,
        Christian Brauner <christian@brauner.io>, andres@anarazel.de,
        Jeff Layton <jlayton@redhat.com>, dray@redhat.com,
        Karel Zak <kzak@redhat.com>, keyrings@vger.kernel.org,
        Linux API <linux-api@vger.kernel.org>,
        linux-fsdevel@vger.kernel.org,
        LSM <linux-security-module@vger.kernel.org>,
        linux-kernel@vger.kernel.org
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On Wed, Aug 5, 2020 at 1:36 PM Ian Kent <raven@themaw.net> wrote:
>

> I can see in the kernel code that an error is returned if the message
> buffer is full when trying to add a message, I just can't see where
> to get it in the libmount code.
>
> That's not really a communication protocol problem.
>
> Still I need to work out how to detect it, maybe it is seen by
> the code in libmount already and I simply can't see what I need
> to do to recognise it ...
>
> So I'm stuck wanting to verify I have got everything that was
> sent and am having trouble moving on from that.

This is the commit that should add the overrun detection capability:

e7d553d69cf6 ("pipe: Add notification lossage handling")

Thanks,
Miklos