From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Howells Date: Tue, 28 May 2019 23:08:37 +0000 Subject: Re: [PATCH 3/7] vfs: Add a mount-notification facility Message-Id: <30028.1559084917@warthog.procyon.org.uk> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit List-Id: References: <10418.1559084686@warthog.procyon.org.uk> <155905930702.7587.7100265859075976147.stgit@warthog.procyon.org.uk> <155905933492.7587.6968545866041839538.stgit@warthog.procyon.org.uk> In-Reply-To: <10418.1559084686@warthog.procyon.org.uk> To: Jann Horn Cc: dhowells@redhat.com, Al Viro , raven@themaw.net, linux-fsdevel , Linux API , linux-block@vger.kernel.org, keyrings@vger.kernel.org, linux-security-module , kernel list David Howells wrote: > > It might make sense to redesign this stuff so that watches don't hold > > references on the object being watched. > > I explicitly made it hold a reference so that if you place a watch on an > automounted mount it stops it from expiring. > > Further, if I create a watch on something, *should* it be unmountable, just as > if I had a file open there or had chdir'd into there? It gets trickier than that as I need a ref on the dentry on which the watch is rooted to prevent it from getting culled. David