I came across a problem where if the containers are running then it affects the unmount process of the system's mount points. I am not using these mount points as shared mounts with container.
For example, I am using SD card and NAND as external storage device and mounting it to a mount point in the ramfs. Then I am launching containers and then when I try to unmount the NAND partition then my "unmount" call succeeds but I don't see the UBIFS hooks being called and because of that my UBI detach process fails. When I stopped the container then I see that kernel is calling the unmount as I see my debug prints inside the UBIFS for unmounting that partition. If I tried to mount my NAND partition once the container is up and try to unmount then it does unmount and detach without issue. It seems like there is an issue with namespace. I am using 4.1.8 kernel . I traced the kernel code and I see that copy_mnt_ns is calling copy_tree and which basically increasing the active counts of the super block of my host mount points (NAND, SD cards). I am using container but I do not wish to share any of my host storage media with container so in my container configuration I am only mounting the tmpfs as the rootfs of container is in in tmpfs of host. But, still I can't umount completely my host storage media if containers are running. I have attached the log of the container start process with debugging and where you can see it is increasing the super block active counts for "ubifs". -- Ronak A Desai Sr. Software Engineer Airborne Information Solutions / RC Linux Platform Software MS 131-100, C Ave NE, Cedar Rapids, IA, 52498, USA ronak.de...@rockwellcollins.com https://www.rockwellcollins.com/
Starting lxc1 Application: ---> alloc_super, 220, atomic_read(&s->s_active) = 1, name = ---> vfs_kern_mount, 953 ---> fs/namespace.c, copy_mnt_ns, 2875 ---> fs/namespace.c, copy_tree, 1742 ---> clone_mnt, 1011, atomic_read(&sb->s_active) = 3, name = rootfs ---> fs/namespace.c, copy_tree, 1773 ---> clone_mnt, 1011, atomic_read(&sb->s_active) = 3, name = devtmpfs ---> fs/namespace.c, copy_tree, 1773 ---> clone_mnt, 1011, atomic_read(&sb->s_active) = 3, name = devpts ---> fs/namespace.c, copy_tree, 1773 ---> clone_mnt, 1011, atomic_read(&sb->s_active) = 2, name = tmpfs ---> fs/namespace.c, copy_tree, 1773 ---> clone_mnt, 1011, atomic_read(&sb->s_active) = 3, name = proc ---> fs/namespace.c, copy_tree, 1773 ---> clone_mnt, 1011, atomic_read(&sb->s_active) = 2, name = tmpfs ---> fs/namespace.c, copy_tree, 1773 ---> clone_mnt, 1011, atomic_read(&sb->s_active) = 2, name = tmpfs ---> fs/namespace.c, copy_tree, 1773 ---> clone_mnt, 1011, atomic_read(&sb->s_active) = 2, name = tmpfs ---> fs/namespace.c, copy_tree, 1773 ---> clone_mnt, 1011, atomic_read(&sb->s_active) = 2, name = sysfs ---> fs/namespace.c, copy_tree, 1773 ---> clone_mnt, 1011, atomic_read(&sb->s_active) = 2, name = tmpfs ---> fs/namespace.c, copy_tree, 1773 ---> clone_mnt, 1011, atomic_read(&sb->s_active) = 2, name = cgroup ---> fs/namespace.c, copy_tree, 1773 ---> clone_mnt, 1011, atomic_read(&sb->s_active) = 2, name = cgroup ---> fs/namespace.c, copy_tree, 1773 ---> clone_mnt, 1011, atomic_read(&sb->s_active) = 2, name = cgroup ---> fs/namespace.c, copy_tree, 1773 ---> clone_mnt, 1011, atomic_read(&sb->s_active) = 2, name = cgroup ---> fs/namespace.c, copy_tree, 1773 ---> clone_mnt, 1011, atomic_read(&sb->s_active) = 2, name = cgroup ---> fs/namespace.c, copy_tree, 1773 ---> clone_mnt, 1011, atomic_read(&sb->s_active) = 2, name = cgroup ---> fs/namespace.c, copy_tree, 1773 ---> clone_mnt, 1011, atomic_read(&sb->s_active) = 2, name = cgroup ---> fs/namespace.c, copy_tree, 1773 ---> clone_mnt, 1011, atomic_read(&sb->s_active) = 2, name = ubifs ---> fs/namespace.c, copy_tree, 1773 ---> clone_mnt, 1011, atomic_read(&sb->s_active) = 2, name = ubifs ---> alloc_super, 220, atomic_read(&s->s_active) = 1, name = EXT3-fs (loop0): error: can't find ext3 filesystem on dev loop0. ---> deactivate_locked_super, 284 ---> deactivate_locked_super, 288 ---> kill_block_super, 1050 ---> generic_shutdown_super, 409 ---> deactivate_locked_super, 299 ---> deactivate_locked_super, 301 ---> alloc_super, 220, atomic_read(&s->s_active) = 1, name = EXT2-fs (loop0): error: can't find an ext2 filesystem on dev loop0. ---> deactivate_locked_super, 284 ---> deactivate_locked_super, 288 ---> kill_block_super, 1050 ---> generic_shutdown_super, 409 ---> deactivate_locked_super, 299 ---> deactivate_locked_super, 301 ---> alloc_super, 220, atomic_read(&s->s_active) = 1, name = EXT4-fs (loop0): VFS: Can't find ext4 filesystem ---> deactivate_locked_super, 284 ---> deactivate_locked_super, 288 ---> kill_block_super, 1050 ---> generic_shutdown_super, 409 ---> deactivate_locked_super, 299 ---> deactivate_locked_super, 301 ---> alloc_super, 220, atomic_read(&s->s_active) = 1, name = ---> vfs_kern_mount, 953 device veth4YTWEM entered promiscuous mode ---> kern_unmount, 3251 ---> mntput_no_expire, 1144 ---> cleanup_mnt, 1063 ---> cleanup_mnt, 1069 ---> cleanup_mnt, 1071 ---> cleanup_mnt, 1073 ---> deactivate_super, 321 ---> deactivate_super, 323 ---> deactivate_locked_super, 284 ---> deactivate_locked_super, 288 ---> kill_anon_super, 896 ---> generic_shutdown_super, 409 ---> generic_shutdown_super, 415 ---> deactivate_locked_super, 299 ---> deactivate_locked_super, 301 ---> cleanup_mnt, 1075 device vethXAIUQR entered promiscuous mode lxcbr1: port 1(vethXAIUQR) entered forwarding state lxcbr1: port 1(vethXAIUQR) entered forwarding state lxcbr1: port 1(vethXAIUQR) entered disabled state ---> fs/namespace.c, copy_mnt_ns, 2875 ---> fs/namespace.c, copy_tree, 1742 ---> clone_mnt, 1011, atomic_read(&sb->s_active) = 4, name = rootfs ---> fs/namespace.c, copy_tree, 1773 ---> clone_mnt, 1011, atomic_read(&sb->s_active) = 4, name = devtmpfs ---> fs/namespace.c, copy_tree, 1773 ---> clone_mnt, 1011, atomic_read(&sb->s_active) = 4, name = devpts ---> fs/namespace.c, copy_tree, 1773 ---> clone_mnt, 1011, atomic_read(&sb->s_active) = 3, name = tmpfs ---> fs/namespace.c, copy_tree, 1773 ---> clone_mnt, 1011, atomic_read(&sb->s_active) = 4, name = proc ---> fs/namespace.c, copy_tree, 1773 ---> clone_mnt, 1011, atomic_read(&sb->s_active) = 3, name = tmpfs ---> fs/namespace.c, copy_tree, 1773 ---> clone_mnt, 1011, atomic_read(&sb->s_active) = 3, name = tmpfs ---> fs/namespace.c, copy_tree, 1773 ---> clone_mnt, 1011, atomic_read(&sb->s_active) = 3, name = tmpfs ---> fs/namespace.c, copy_tree, 1773 ---> clone_mnt, 1011, atomic_read(&sb->s_active) = 2, name = loop0 ---> fs/namespace.c, copy_tree, 1773 ---> clone_mnt, 1011, atomic_read(&sb->s_active) = 3, name = sysfs ---> fs/namespace.c, copy_tree, 1773 ---> clone_mnt, 1011, atomic_read(&sb->s_active) = 3, name = tmpfs ---> fs/namespace.c, copy_tree, 1773 ---> clone_mnt, 1011, atomic_read(&sb->s_active) = 3, name = cgroup ---> fs/namespace.c, copy_tree, 1773 ---> clone_mnt, 1011, atomic_read(&sb->s_active) = 3, name = cgroup ---> fs/namespace.c, copy_tree, 1773 ---> clone_mnt, 1011, atomic_read(&sb->s_active) = 3, name = cgroup ---> fs/namespace.c, copy_tree, 1773 ---> clone_mnt, 1011, atomic_read(&sb->s_active) = 3, name = cgroup ---> fs/namespace.c, copy_tree, 1773 ---> clone_mnt, 1011, atomic_read(&sb->s_active) = 3, name = cgroup ---> fs/namespace.c, copy_tree, 1773 ---> clone_mnt, 1011, atomic_read(&sb->s_active) = 3, name = cgroup ---> fs/namespace.c, copy_tree, 1773 ---> clone_mnt, 1011, atomic_read(&sb->s_active) = 3, name = cgroup ---> fs/namespace.c, copy_tree, 1773 ---> clone_mnt, 1011, atomic_read(&sb->s_active) = 3, name = ubifs ---> fs/namespace.c, copy_tree, 1773 ---> clone_mnt, 1011, atomic_read(&sb->s_active) = 3, name = ubifs ---> alloc_super, 220, atomic_read(&s->s_active) = 1, name = ---> vfs_kern_mount, 953 ---> alloc_super, 220, atomic_read(&s->s_active) = 1, name = ---> vfs_kern_mount, 953 ---> free_user_ns, 147 ---> free_user_ns, 149 ---> free_user_ns, 147 ---> free_user_ns, 149 ---> fs/namespace.c, do_loopback, 2181 ---> clone_mnt, 1011, atomic_read(&sb->s_active) = 3, name = loop0 eth0: renamed from vethQMW0V2 eth3: renamed from veth6AR9T2 lxcbr0: port 1(veth4YTWEM) entered forwarding state lxcbr0: port 1(veth4YTWEM) entered forwarding state lxcbr1: port 1(vethXAIUQR) entered forwarding state lxcbr1: port 1(vethXAIUQR) entered forwarding state ---> alloc_super, 220, atomic_read(&s->s_active) = 1, name = ---> vfs_kern_mount, 953 ---> grab_super, 353, atomic_read(&s->s_active) = 2, name = proc ---> vfs_kern_mount, 953 ---> fs/namespace.c, do_loopback, 2181 ---> clone_mnt, 1011, atomic_read(&sb->s_active) = 3, name = proc ---> fs/namespace.c, do_loopback, 2181 ---> clone_mnt, 1011, atomic_read(&sb->s_active) = 4, name = proc ---> attach_mnt, 862 ---> fs/namespace.c, do_loopback, 2181 ---> clone_mnt, 1011, atomic_read(&sb->s_active) = 5, name = proc ---> alloc_super, 220, atomic_read(&s->s_active) = 1, name = ---> vfs_kern_mount, 953 ---> fs/namespace.c, do_loopback, 2181 ---> clone_mnt, 1011, atomic_read(&sb->s_active) = 4, name = tmpfs ---> fs/namespace.c, do_loopback, 2181 ---> clone_mnt, 1011, atomic_read(&sb->s_active) = 5, name = devtmpfs ---> fs/namespace.c, do_loopback, 2181 ---> clone_mnt, 1011, atomic_read(&sb->s_active) = 6, name = devtmpfs ---> fs/namespace.c, do_loopback, 2181 ---> clone_mnt, 1011, atomic_read(&sb->s_active) = 7, name = devtmpfs ---> fs/namespace.c, do_loopback, 2181 ---> clone_mnt, 1011, atomic_read(&sb->s_active) = 8, name = devtmpfs ---> fs/namespace.c, do_loopback, 2181 ---> clone_mnt, 1011, atomic_read(&sb->s_active) = 9, name = devtmpfs ---> fs/namespace.c, do_loopback, 2181 ---> clone_mnt, 1011, atomic_read(&sb->s_active) = 10, name = devtmpfs ---> fs/namespace.c, do_loopback, 2181 ---> clone_mnt, 1011, atomic_read(&sb->s_active) = 5, name = devpts ---> fs/namespace.c, do_loopback, 2176 ---> fs/namespace.c, copy_tree, 1742 ---> clone_mnt, 1011, atomic_read(&sb->s_active) = 4, name = loop0 ---> fs/namespace.c, copy_tree, 1773 ---> clone_mnt, 1011, atomic_read(&sb->s_active) = 2, name = tmpfs ---> fs/namespace.c, copy_tree, 1773 ---> clone_mnt, 1011, atomic_read(&sb->s_active) = 11, name = devtmpfs ---> fs/namespace.c, copy_tree, 1773 ---> clone_mnt, 1011, atomic_read(&sb->s_active) = 12, name = devtmpfs ---> fs/namespace.c, copy_tree, 1773 ---> clone_mnt, 1011, atomic_read(&sb->s_active) = 13, name = devtmpfs ---> fs/namespace.c, copy_tree, 1773 ---> clone_mnt, 1011, atomic_read(&sb->s_active) = 14, name = devtmpfs ---> fs/namespace.c, copy_tree, 1773 ---> clone_mnt, 1011, atomic_read(&sb->s_active) = 15, name = devtmpfs ---> fs/namespace.c, copy_tree, 1773 ---> clone_mnt, 1011, atomic_read(&sb->s_active) = 16, name = devtmpfs ---> fs/namespace.c, copy_tree, 1773 ---> clone_mnt, 1011, atomic_read(&sb->s_active) = 6, name = devpts ---> fs/namespace.c, copy_tree, 1773 ---> clone_mnt, 1011, atomic_read(&sb->s_active) = 6, name = proc ---> fs/namespace.c, copy_tree, 1773 ---> clone_mnt, 1011, atomic_read(&sb->s_active) = 7, name = proc ---> fs/namespace.c, copy_tree, 1773 ---> clone_mnt, 1011, atomic_read(&sb->s_active) = 8, name = proc ---> fs/namespace.c, copy_tree, 1773 ---> clone_mnt, 1011, atomic_read(&sb->s_active) = 9, name = proc ---> fs/namespace.c, copy_tree, 1773 ---> clone_mnt, 1011, atomic_read(&sb->s_active) = 2, name = tmpfs ---> fs/namespace.c, copy_tree, 1773 ---> clone_mnt, 1011, atomic_read(&sb->s_active) = 5, name = tmpfs ---> SYSC_umount, 1688 ---> SYSC_umount, 1688 ---> SYSC_umount, 1688 ---> SYSC_umount, 1688 ---> SYSC_umount, 1688 ---> SYSC_umount, 1688 ---> do_umount, 1502 ---> umount_tree, 1441 ---> umount_tree, 1444 ---> propagate_mount_unlock, 381 ---> umount_tree, 1450 ---> umount_tree, 1450 ---> umount_tree, 1450 ---> umount_tree, 1450 ---> umount_tree, 1450 ---> umount_tree, 1450 ---> umount_tree, 1450 ---> umount_tree, 1450 ---> umount_tree, 1450 ---> umount_tree, 1450 ---> umount_tree, 1450 ---> umount_tree, 1450 ---> umount_tree, 1450 ---> umount_tree, 1450 ---> umount_tree, 1450 ---> umount_tree, 1457 ---> umount_tree, 1457 ---> umount_tree, 1457 ---> umount_tree, 1457 ---> umount_tree, 1457 ---> umount_tree, 1457 ---> umount_tree, 1457 ---> umount_tree, 1457 ---> umount_tree, 1457 ---> umount_tree, 1457 ---> umount_tree, 1457 ---> umount_tree, 1457 ---> umount_tree, 1457 ---> umount_tree, 1457 ---> umount_tree, 1457 ---> __propagate_umount, 421 ---> __propagate_umount, 421 ---> __propagate_umount, 421 ---> __propagate_umount, 421 ---> __propagate_umount, 421 ---> __propagate_umount, 421 ---> __propagate_umount, 421 ---> __propagate_umount, 421 ---> __propagate_umount, 421 ---> __propagate_umount, 421 ---> __propagate_umount, 421 ---> __propagate_umount, 421 ---> __propagate_umount, 421 ---> __propagate_umount, 421 ---> __propagate_umount, 421 ---> umount_tree, 1475 ---> disconnect_mount, 1427 ---> umount_tree, 1477 ---> umount_mnt, 834 ---> umount_tree, 1490 ---> umount_tree, 1475 ---> disconnect_mount, 1427 ---> umount_tree, 1477 ---> umount_mnt, 834 ---> umount_tree, 1490 ---> umount_tree, 1475 ---> disconnect_mount, 1427 ---> umount_tree, 1477 ---> umount_mnt, 834 ---> umount_tree, 1490 ---> umount_tree, 1475 ---> disconnect_mount, 1427 ---> umount_tree, 1477 ---> umount_mnt, 834 ---> umount_tree, 1490 ---> umount_tree, 1475 ---> disconnect_mount, 1427 ---> umount_tree, 1477 ---> umount_mnt, 834 ---> umount_tree, 1490 ---> umount_tree, 1475 ---> disconnect_mount, 1427 ---> umount_tree, 1477 ---> umount_mnt, 834 ---> umount_tree, 1490 ---> umount_tree, 1475 ---> disconnect_mount, 1427 ---> umount_tree, 1477 ---> umount_mnt, 834 ---> umount_tree, 1490 ---> umount_tree, 1475 ---> disconnect_mount, 1427 ---> umount_tree, 1477 ---> umount_mnt, 834 ---> umount_tree, 1490 ---> umount_tree, 1475 ---> disconnect_mount, 1427 ---> umount_tree, 1477 ---> umount_mnt, 834 ---> umount_tree, 1490 ---> umount_tree, 1475 ---> disconnect_mount, 1427 ---> umount_tree, 1477 ---> umount_mnt, 834 ---> umount_tree, 1490 ---> umount_tree, 1475 ---> disconnect_mount, 1427 ---> umount_tree, 1477 ---> umount_mnt, 834 ---> umount_tree, 1490 ---> umount_tree, 1475 ---> disconnect_mount, 1427 ---> umount_tree, 1477 ---> umount_mnt, 834 ---> umount_tree, 1490 ---> umount_tree, 1475 ---> disconnect_mount, 1427 ---> umount_tree, 1477 ---> umount_mnt, 834 ---> umount_tree, 1490 ---> umount_tree, 1475 ---> disconnect_mount, 1427 ---> umount_tree, 1477 ---> umount_mnt, 834 ---> umount_tree, 1490 ---> umount_tree, 1475 ---> disconnect_mount, 1409 ---> umount_tree, 1477 ---> umount_mnt, 834 ---> umount_tree, 1490 ---> drop_mountpoint, 199 ---> drop_mountpoint, 199 ---> mntput_no_expire, 1135 ---> drop_mountpoint, 199 ---> mntput_no_expire, 1135 ---> drop_mountpoint, 199 ---> mntput_no_expire, 1135 ---> drop_mountpoint, 199 ---> mntput_no_expire, 1135 ---> drop_mountpoint, 199 ---> mntput_no_expire, 1135 ---> drop_mountpoint, 199 ---> mntput_no_expire, 1135 ---> drop_mountpoint, 199 ---> mntput_no_expire, 1135 ---> drop_mountpoint, 199 ---> mntput_no_expire, 1135 ---> drop_mountpoint, 199 ---> mntput_no_expire, 1135 ---> drop_mountpoint, 199 ---> mntput_no_expire, 1135 ---> drop_mountpoint, 199 ---> mntput_no_expire, 1135 ---> drop_mountpoint, 199 ---> mntput_no_expire, 1135 ---> drop_mountpoint, 199 ---> mntput_no_expire, 1135 ---> drop_mountpoint, 199 ---> mntput_no_expire, 1135 ---> SYSC_umount, 1688 ---> mntput_no_expire, 1135 ---> __cleanup_mnt, 1082 ---> cleanup_mnt, 1063 ---> cleanup_mnt, 1069 ---> cleanup_mnt, 1071 ---> cleanup_mnt, 1073 ---> deactivate_super, 328, atomic_read(&s->s_active) = 1, name = tmpfs ---> cleanup_mnt, 1075 ---> __cleanup_mnt, 1082 ---> cleanup_mnt, 1063 ---> cleanup_mnt, 1069 ---> cleanup_mnt, 1071 ---> cleanup_mnt, 1073 ---> deactivate_super, 328, atomic_read(&s->s_active) = 15, name = devtmpfs ---> cleanup_mnt, 1075 ---> __cleanup_mnt, 1082 ---> cleanup_mnt, 1063 ---> cleanup_mnt, 1069 ---> cleanup_mnt, 1071 ---> cleanup_mnt, 1073 ---> deactivate_super, 328, atomic_read(&s->s_active) = 14, name = devtmpfs ---> cleanup_mnt, 1075 ---> __cleanup_mnt, 1082 ---> cleanup_mnt, 1063 ---> cleanup_mnt, 1069 ---> cleanup_mnt, 1071 ---> cleanup_mnt, 1073 ---> deactivate_super, 328, atomic_read(&s->s_active) = 13, name = devtmpfs ---> cleanup_mnt, 1075 ---> __cleanup_mnt, 1082 ---> cleanup_mnt, 1063 ---> cleanup_mnt, 1069 ---> cleanup_mnt, 1071 ---> cleanup_mnt, 1073 ---> deactivate_super, 328, atomic_read(&s->s_active) = 12, name = devtmpfs ---> cleanup_mnt, 1075 ---> __cleanup_mnt, 1082 ---> cleanup_mnt, 1063 ---> cleanup_mnt, 1069 ---> cleanup_mnt, 1071 ---> cleanup_mnt, 1073 ---> deactivate_super, 328, atomic_read(&s->s_active) = 11, name = devtmpfs ---> cleanup_mnt, 1075 ---> __cleanup_mnt, 1082 ---> cleanup_mnt, 1063 ---> cleanup_mnt, 1069 ---> cleanup_mnt, 1071 ---> cleanup_mnt, 1073 ---> deactivate_super, 328, atomic_read(&s->s_active) = 10, name = devtmpfs ---> cleanup_mnt, 1075 ---> __cleanup_mnt, 1082 ---> cleanup_mnt, 1063 ---> cleanup_mnt, 1069 ---> cleanup_mnt, 1071 ---> cleanup_mnt, 1073 ---> deactivate_super, 328, atomic_read(&s->s_active) = 5, name = devpts ---> cleanup_mnt, 1075 ---> __cleanup_mnt, 1082 ---> cleanup_mnt, 1063 ---> cleanup_mnt, 1069 ---> cleanup_mnt, 1071 ---> cleanup_mnt, 1073 ---> deactivate_super, 328, atomic_read(&s->s_active) = 8, name = proc ---> cleanup_mnt, 1075 ---> __cleanup_mnt, 1082 ---> cleanup_mnt, 1063 ---> cleanup_mnt, 1069 ---> cleanup_mnt, 1071 ---> cleanup_mnt, 1073 ---> deactivate_super, 328, atomic_read(&s->s_active) = 7, name = proc ---> cleanup_mnt, 1075 ---> __cleanup_mnt, 1082 ---> cleanup_mnt, 1063 ---> cleanup_mnt, 1069 ---> cleanup_mnt, 1071 ---> cleanup_mnt, 1073 ---> deactivate_super, 328, atomic_read(&s->s_active) = 6, name = proc ---> cleanup_mnt, 1075 ---> __cleanup_mnt, 1082 ---> cleanup_mnt, 1063 ---> cleanup_mnt, 1069 ---> cleanup_mnt, 1071 ---> cleanup_mnt, 1073 ---> deactivate_super, 328, atomic_read(&s->s_active) = 5, name = proc ---> cleanup_mnt, 1075 ---> __cleanup_mnt, 1082 ---> cleanup_mnt, 1063 ---> cleanup_mnt, 1069 ---> cleanup_mnt, 1071 ---> cleanup_mnt, 1073 ---> deactivate_super, 328, atomic_read(&s->s_active) = 1, name = tmpfs ---> cleanup_mnt, 1075 ---> __cleanup_mnt, 1082 ---> cleanup_mnt, 1063 ---> cleanup_mnt, 1069 ---> cleanup_mnt, 1071 ---> cleanup_mnt, 1073 ---> deactivate_super, 328, atomic_read(&s->s_active) = 4, name = tmpfs ---> cleanup_mnt, 1075 ---> __cleanup_mnt, 1082 ---> cleanup_mnt, 1063 ---> cleanup_mnt, 1069 ---> cleanup_mnt, 1071 ---> cleanup_mnt, 1073 ---> deactivate_super, 328, atomic_read(&s->s_active) = 3, name = loop0 ---> cleanup_mnt, 1075 ---> SYSC_umount, 1688 ---> SYSC_umount, 1688 ---> SYSC_umount, 1688 ---> SYSC_umount, 1688 ---> SYSC_umount, 1688 ---> SYSC_umount, 1688 ---> SYSC_umount, 1688 ---> SYSC_umount, 1688 ---> SYSC_umount, 1688 ---> SYSC_umount, 1688 ---> SYSC_umount, 1688 ---> SYSC_umount, 1688 ---> SYSC_umount, 1688 ---> SYSC_umount, 1688 ---> SYSC_umount, 1688 ---> SYSC_umount, 1688 ---> SYSC_umount, 1688 ---> SYSC_umount, 1688 ---> SYSC_umount, 1688 ---> SYSC_umount, 1688 ---> SYSC_umount, 1688 ---> SYSC_umount, 1688 ---> SYSC_umount, 1688 ---> SYSC_umount, 1688 ---> SYSC_umount, 1688 ---> SYSC_umount, 1688 ---> SYSC_umount, 1688 ---> SYSC_umount, 1688 ---> SYSC_umount, 1688 ---> SYSC_umount, 1688 ---> SYSC_umount, 1688 ---> SYSC_umount, 1688 ---> SYSC_umount, 1688 ---> SYSC_umount, 1688 ---> SYSC_umount, 1688 ---> SYSC_umount, 1688 ---> SYSC_umount, 1688 ---> SYSC_umount, 1688 ---> SYSC_umount, 1688 ---> SYSC_umount, 1688 ---> SYSC_umount, 1688 ---> SYSC_umount, 1688 ---> SYSC_umount, 1688 ---> SYSC_umount, 1688 ---> SYSC_umount, 1688 ---> SYSC_umount, 1688 ---> SYSC_umount, 1688 ---> SYSC_umount, 1688 ---> SYSC_umount, 1688 ---> SYSC_umount, 1688 ---> SYSC_umount, 1688 ---> SYSC_umount, 1688 ---> SYSC_umount, 1688 ---> SYSC_umount, 1688 ---> alloc_super, 220, atomic_read(&s->s_active) = 1, name = ---> vfs_kern_mount, 953 ---> fs/namespace.c, do_loopback, 2181 ---> clone_mnt, 1011, atomic_read(&sb->s_active) = 2, name = devpts ---> fs/namespace.c, do_loopback, 2181 ---> clone_mnt, 1011, atomic_read(&sb->s_active) = 3, name = devpts ---> fs/namespace.c, do_loopback, 2181 ---> clone_mnt, 1011, atomic_read(&sb->s_active) = 4, name = devpts ##################### umount call is successful but it does not call the UBIFS unmount as it fails in deactivate_super ################## # umount /opt/logging/ ---> do_umount, 1502 ---> propagate_mount_busy, 344 ---> do_refcount_check, 324 ---> umount_tree, 1441 ---> umount_tree, 1444 ---> propagate_mount_unlock, 381 ---> umount_tree, 1450 ---> umount_tree, 1457 ---> __propagate_umount, 421 ---> umount_tree, 1475 ---> disconnect_mount, 1392 ---> umount_tree, 1477 ---> umount_mnt, 834 ---> umount_tree, 1490 ---> drop_mountpoint, 199 ---> SYSC_umount, 1688 ---> mntput_no_expire, 1135 ---> __cleanup_mnt, 1082 ---> cleanup_mnt, 1063 ---> cleanup_mnt, 1069 ---> cleanup_mnt, 1071 ---> cleanup_mnt, 1073 ---> deactivate_super, 328, atomic_read(&s->s_active) = 2, name = ubifs ---> cleanup_mnt, 1075 #
