Bug 983436

Summary:	remounting a bind mount exponentially fills up /proc/mounts
Product:	[Fedora] Fedora	Reporter:	Pierre Ossman <ossman>
Component:	kernel	Assignee:	Kernel Maintainer List <kernel-maint>
Status:	CLOSED INSUFFICIENT_DATA	QA Contact:	Fedora Extras Quality Assurance <extras-qa>
Severity:	unspecified	Docs Contact:
Priority:	unspecified
Version:	20	CC:	gansalmon, itamar, jonas, jonathan, kernel-maint, madhu.chinakonda
Target Milestone:	---	Keywords:	Reopened
Target Release:	---	Flags:	jforbes: needinfo?
Hardware:	Unspecified
OS:	Unspecified
Whiteboard:
Fixed In Version:		Doc Type:	Bug Fix
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2014-12-10 15:00:47 UTC	Type:	Bug
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:

Description Pierre Ossman 2013-07-11 08:39:50 UTC

Kernel kernel-3.9.6-200.fc18.x86_64:

[root@ossman mnt]# grep lv_local /proc/mounts 
/dev/mapper/vg_ossman-lv_local /local ext4 rw,seclabel,relatime,data=ordered 0 0
[root@ossman mnt]# mount -o bind /local /mnt/foo
[root@ossman mnt]# grep lv_local /proc/mounts 
/dev/mapper/vg_ossman-lv_local /local ext4 rw,seclabel,relatime,data=ordered 0 0
/dev/mapper/vg_ossman-lv_local /mnt/foo ext4 rw,seclabel,relatime,data=ordered 0 0
[root@ossman mnt]# mount -o bind /local /mnt/foo
[root@ossman mnt]# grep lv_local /proc/mounts 
/dev/mapper/vg_ossman-lv_local /local ext4 rw,seclabel,relatime,data=ordered 0 0
/dev/mapper/vg_ossman-lv_local /mnt/foo ext4 rw,seclabel,relatime,data=ordered 0 0
/dev/mapper/vg_ossman-lv_local /mnt/foo ext4 rw,seclabel,relatime,data=ordered 0 0
/dev/mapper/vg_ossman-lv_local /local ext4 rw,seclabel,relatime,data=ordered 0 0
[root@ossman mnt]# mount -o bind /local /mnt/foo
[root@ossman mnt]# grep lv_local /proc/mounts 
/dev/mapper/vg_ossman-lv_local /local ext4 rw,seclabel,relatime,data=ordered 0 0
/dev/mapper/vg_ossman-lv_local /mnt/foo ext4 rw,seclabel,relatime,data=ordered 0 0
/dev/mapper/vg_ossman-lv_local /mnt/foo ext4 rw,seclabel,relatime,data=ordered 0 0
/dev/mapper/vg_ossman-lv_local /local ext4 rw,seclabel,relatime,data=ordered 0 0
/dev/mapper/vg_ossman-lv_local /mnt/foo ext4 rw,seclabel,relatime,data=ordered 0 0
/dev/mapper/vg_ossman-lv_local /local ext4 rw,seclabel,relatime,data=ordered 0 0
/dev/mapper/vg_ossman-lv_local /mnt/foo ext4 rw,seclabel,relatime,data=ordered 0 0
/dev/mapper/vg_ossman-lv_local /local ext4 rw,seclabel,relatime,data=ordered 0 0
[root@ossman mnt]# mount -o bind /local /mnt/foo
[root@ossman mnt]# grep lv_local /proc/mounts 
/dev/mapper/vg_ossman-lv_local /local ext4 rw,seclabel,relatime,data=ordered 0 0
/dev/mapper/vg_ossman-lv_local /mnt/foo ext4 rw,seclabel,relatime,data=ordered 0 0
/dev/mapper/vg_ossman-lv_local /mnt/foo ext4 rw,seclabel,relatime,data=ordered 0 0
/dev/mapper/vg_ossman-lv_local /local ext4 rw,seclabel,relatime,data=ordered 0 0
/dev/mapper/vg_ossman-lv_local /mnt/foo ext4 rw,seclabel,relatime,data=ordered 0 0
/dev/mapper/vg_ossman-lv_local /local ext4 rw,seclabel,relatime,data=ordered 0 0
/dev/mapper/vg_ossman-lv_local /mnt/foo ext4 rw,seclabel,relatime,data=ordered 0 0
/dev/mapper/vg_ossman-lv_local /local ext4 rw,seclabel,relatime,data=ordered 0 0
/dev/mapper/vg_ossman-lv_local /mnt/foo ext4 rw,seclabel,relatime,data=ordered 0 0
/dev/mapper/vg_ossman-lv_local /local ext4 rw,seclabel,relatime,data=ordered 0 0
/dev/mapper/vg_ossman-lv_local /mnt/foo ext4 rw,seclabel,relatime,data=ordered 0 0
/dev/mapper/vg_ossman-lv_local /local ext4 rw,seclabel,relatime,data=ordered 0 0
/dev/mapper/vg_ossman-lv_local /mnt/foo ext4 rw,seclabel,relatime,data=ordered 0 0
/dev/mapper/vg_ossman-lv_local /local ext4 rw,seclabel,relatime,data=ordered 0 0
/dev/mapper/vg_ossman-lv_local /mnt/foo ext4 rw,seclabel,relatime,data=ordered 0 0
/dev/mapper/vg_ossman-lv_local /local ext4 rw,seclabel,relatime,data=ordered 0 0

Comment 1 Pierre Ossman 2013-07-11 08:41:06 UTC

And after a few rounds you also wedge things:

[root@ossman mnt]# umount /mnt/foo
umount: /mnt/foo: target is busy.

Doing umount -l at this point hangs the system.

Comment 2 Josh Boyer 2013-09-18 20:51:54 UTC

*********** MASS BUG UPDATE **************

We apologize for the inconvenience.  There is a large number of bugs to go through and several of them have gone stale.  Due to this, we are doing a mass bug update across all of the Fedora 19 kernel bugs.

Fedora 19 has now been rebased to 3.11.1-200.fc19.  Please test this kernel update and let us know if you issue has been resolved or if it is still present with the newer kernel.

If you experience different issues, please open a new bug report for those.

Comment 3 Pierre Ossman 2013-09-19 08:53:11 UTC

Bug remains in 3.11.1-200.fc19.

Comment 4 Justin M. Forbes 2014-01-03 22:08:38 UTC

*********** MASS BUG UPDATE **************

We apologize for the inconvenience.  There is a large number of bugs to go through and several of them have gone stale.  Due to this, we are doing a mass bug update across all of the Fedora 19 kernel bugs.

Fedora 19 has now been rebased to 3.12.6-200.fc19.  Please test this kernel update (or newer) and let us know if you issue has been resolved or if it is still present with the newer kernel.

If you have moved on to Fedora 20, and are still experiencing this issue, please change the version to Fedora 20.

If you experience different issues, please open a new bug report for those.

Comment 5 Justin M. Forbes 2014-03-10 14:40:16 UTC

*********** MASS BUG UPDATE **************

This bug has been in a needinfo state for more than 1 month and is being closed with insufficient data due to inactivity. If this is still an issue with Fedora 19, please feel free to reopen the bug and provide the additional information requested.

Comment 6 Pierre Ossman 2014-03-10 15:22:57 UTC

Sorry, forgot about this. Still happens with 3.12.8-200.fc19.x86_64.

Comment 7 Justin M. Forbes 2014-05-21 19:30:29 UTC

*********** MASS BUG UPDATE **************

We apologize for the inconvenience.  There is a large number of bugs to go through and several of them have gone stale.  Due to this, we are doing a mass bug update across all of the Fedora 19 kernel bugs.

Fedora 19 has now been rebased to 3.14.4-100.fc19.  Please test this kernel update (or newer) and let us know if you issue has been resolved or if it is still present with the newer kernel.

If you have moved on to Fedora 20, and are still experiencing this issue, please change the version to Fedora 20.

If you experience different issues, please open a new bug report for those.

Comment 8 Pierre Ossman 2014-05-22 12:11:42 UTC

Still happens with 3.14.4-200.fc20.x86_64.

Comment 9 Jonas Jonsson 2014-07-25 12:07:01 UTC

This problem doesn't happen on a Debian unstable system, 3.14.4-1. 
It doesn't happen on an ancient Fedora 14 machine either, 2.6.35.14-106.fc14.x86_64.

I've tested the vanilla linux kernel v3.15 and v3.16-rc6 on a minimal busybox based system. Unable to reproduce the problem there. The kernel config matches the one used for 3.15.4-200.fc20.x86_64.

I can reproduce this on 3.15.4-200.fc20.x86_64.

Comment 10 Justin M. Forbes 2014-11-13 16:01:11 UTC

*********** MASS BUG UPDATE **************

We apologize for the inconvenience.  There is a large number of bugs to go through and several of them have gone stale.  Due to this, we are doing a mass bug update across all of the Fedora 20 kernel bugs.

Fedora 20 has now been rebased to 3.17.2-200.fc20.  Please test this kernel update (or newer) and let us know if you issue has been resolved or if it is still present with the newer kernel.

If you have moved on to Fedora 21, and are still experiencing this issue, please change the version to Fedora 21.

If you experience different issues, please open a new bug report for those.

Comment 11 Justin M. Forbes 2014-12-10 15:00:47 UTC

This bug is being closed with INSUFFICIENT_DATA as there has not been a response in over 3 weeks. If you are still experiencing this issue, please reopen and attach the relevant data from the latest kernel you are running and any data that might have been requested previously.