From mboxrd@z Thu Jan 1 00:00:00 1970 From: ebiederm@xmission.com (Eric W. Biederman) Subject: Re: [fuse-devel] fusermount reports "Device or resource busy" but unmounts it anyway Date: Wed, 13 May 2015 09:50:08 -0500 Message-ID: <87bnhoilb3.fsf@x220.int.ebiederm.org> References: <20150512093413.GA19964@redhat.com> <20150513082942.GT29283@redhat.com> Mime-Version: 1.0 Content-Type: text/plain Cc: Miklos Szeredi , fuse-devel , Linux-Fsdevel To: "Richard W.M. Jones" Return-path: Received: from out02.mta.xmission.com ([166.70.13.232]:33309 "EHLO out02.mta.xmission.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934284AbbEMOyq (ORCPT ); Wed, 13 May 2015 10:54:46 -0400 In-Reply-To: <20150513082942.GT29283@redhat.com> (Richard W. M. Jones's message of "Wed, 13 May 2015 09:29:42 +0100") Sender: linux-fsdevel-owner@vger.kernel.org List-ID: "Richard W.M. Jones" writes: > On Wed, May 13, 2015 at 10:27:09AM +0200, Miklos Szeredi wrote: >> [CCs added] >> >> On Tue, May 12, 2015 at 11:34 AM, Richard W.M. Jones wrote: >> > >> > Has something changed in FUSE / the kernel in the past few months so >> > that 'fusermount -u /mp' reports the error: >> > >> > fusermount: failed to unmount /mp: Device or resource busy >> > >> >> That's from the umount2() syscall, and most likely not a fuse issue. >> >> > and returns a non-zero exit code, but the mountpoint is unmounted >> > anyway? >> >> Is this in 4.1-rc? If so, then the recent fs/namespace.c patches from >> Eric Biederman would be suspect. > > Yes, this is reproducible with: > > kernel-4.1.0-0.rc2.git3.1.fc23.x86_64 (from Fedora Rawide) > fuse-2.9.3-4.fc22.x86_64 > > I will see if I can make a small reproducer and get back. I will be happy to look at this if there is a reasonably small reproducer. I don't think I changed anything that could cause that kind of failure, but I have touched a fair amount of that code recently and at the very least I will be familiar with it. The only case I can imagine is the mount point being deleted. Eric