From mboxrd@z Thu Jan 1 00:00:00 1970 From: C Anthony Risinger Subject: Re: can't unmount Date: Thu, 12 Aug 2010 14:15:01 -0500 Message-ID: <-2313672481500234419@unknownmsgid> References: <4C641969.9070405@noir.com> <4C641A31.4090603@noir.com> <-3215279523596534788@unknownmsgid> <4C6435F6.6030708@noir.com> Mime-Version: 1.0 (iPhone Mail 7D11) Content-Type: text/plain; charset=ISO-8859-1 Cc: "linux-btrfs@vger.kernel.org" To: "K. Richard Pixley" Return-path: In-Reply-To: <4C6435F6.6030708@noir.com> List-ID: On Aug 12, 2010, at 12:57 PM, "K. Richard Pixley" wrote: > On 8/12/10 10:46 , C Anthony Risinger wrote: >> On Aug 12, 2010, at 10:58 AM, "K. Richard Pixley" >> wrote: >>> And should I be worried about what umount -l might be leaving >>> behind? (eg, any unfreed kernel resources) Or is that a reasonable >>> way to deal with this situation on an ongoing basis? >>> >>> On 8/12/10 08:55 , K. Richard Pixley wrote: >>>> I'm running into a situation where I can't unmount a mounted >>>> snapshot. It shows "busy" even though neither lsof nor fuser show >>>> any open files. Umount -f doesn't work although umount -l does. >>>> >>>> Is there anything else I can do to debug this scenario or to clear >>>> the busy status myself? Or am I down to rebooting each time? >>>> >>>> This is on stock ubuntu-10.04, x86. >> You are lazy unmounting, as I understand, you are essentially just >> hiding the fact that the mount was busy to userspace... The mount >> will >> remain active in the kernel until you resolve whatever was stopping >> umount in the first place; kernel will then silently unmount. > Understood. >> Does this affect all of your mounted snapshots, or only a particular >> one? > I'm only mounting one at a time so I haven't noticed. Will check > next time it occurs. More than likely it's just an open app stopping the mount; make sure any GUI stuff isn't looking at the drive, and no terminals are either. I thought that stuff shows up in lsof, but I swear there are cases when things won't. C Anthony [mobile]