Hello, We (Cloudflare) got a strange issue with mount(8) from debian jessie package v2.25.2. Kernel version is 4.4.46 (self compiled, works on other servers). An md device, that is constructed of 12 luks encrypted disks, will not mount to a path /disk/data but it happily mounts to any other path. This is rather unfortunate because we expect to see our device in that path. The same happens with a dummy file-based filesystem[1], so this is unlikely to be related to the device. Here is a debug sample. root:/disk# export LIBMOUNT_DEBUG=0xffff root:/disk# mount /dev/md127 /disk/data 10191: libmount: INIT: debug mask: 0xffff 10191: libmount: INIT: library version: 2.25.0 10191: libmount: INIT: feature: selinux 10191: libmount: INIT: feature: assert 10191: libmount: INIT: feature: debug 10191: libmount: CXT: [0x1a5d080]: ----> allocate 10191: libmount: CXT: [0x1a5d080]: mount: preparing 10191: libmount: CXT: [0x1a5d080]: use default optsmode 10191: libmount: CXT: [0x1a5d080]: OPTSMODE: ignore=0, append=0, prepend=1, replace=0, force=0, fstab=1, mtab=1 10191: libmount: CXT: [0x1a5d080]: fstab not required -- skip 10191: libmount: CXT: [0x1a5d080]: merging mount flags 10191: libmount: CXT: [0x1a5d080]: final flags: VFS=00000000 user=00000000 10191: libmount: CXT: [0x1a5d080]: mount: evaluating permissions 10191: libmount: CXT: [0x1a5d080]: mount: fixing optstr 10191: libmount: CXT: [0x1a5d080]: mount: fixing vfs optstr 10191: libmount: CXT: applying 0x00000000 flags to '(null)' 10191: libmount: CXT: new optstr 'rw' 10191: libmount: CXT: [0x1a5d080]: mount: fixing user optstr 10191: libmount: CXT: applying 0x00000000 flags to '(null)' 10191: libmount: CXT: new optstr '(null)' 10191: libmount: CXT: [0x1a5d080]: fixed options [rc=0]: vfs: 'rw' fs: '(null)' user: '(null)', optstr: 'rw' 10191: libmount: CXT: [0x1a5d080]: preparing source path 10191: libmount: CXT: [0x1a5d080]: srcpath '/dev/md127' 10191: libmount: CACHE: [0x1a5d2c0]: alloc 10191: libmount: CACHE: [0x1a5d2c0]: canonicalize path /dev/md127 10191: libmount: CACHE: [0x1a5d2c0]: add entry [ 1] (path): /dev/md127: /dev/md127 10191: libmount: CXT: [0x1a5d080]: final srcpath '/dev/md127' 10191: libmount: CXT: [0x1a5d080]: preparing target path 10191: libmount: CACHE: [0x1a5d2c0]: canonicalize path /disk/data 10191: libmount: CACHE: [0x1a5d2c0]: add entry [ 2] (path): /disk/data: /disk/data 10191: libmount: CXT: [0x1a5d080]: final target '/disk/data' 10191: libmount: CACHE: [0x1a5d2c0]: get /dev/md127 FS type 10191: libmount: CACHE: [0x1a5d2c0]: tags for /dev/md127 requested 10191: libmount: CACHE: [0x1a5d2c0]: reading tags for: /dev/md127 10191: libmount: CACHE: [0x1a5d2c0]: add entry [ 3] (tag): /dev/md127: UUID 10191: libmount: CACHE: [0x1a5d2c0]: add entry [ 4] (tag): /dev/md127: TYPE 10191: libmount: CACHE: [0x1a5d2c0]: read 2 tags 10191: libmount: CXT: [0x1a5d080]: FS type: ext4 [rc=0] 10191: libmount: CXT: [0x1a5d080]: /sbin/mount.ext4 ... not found 10191: libmount: CXT: [0x1a5d080]: /sbin/fs.d/mount.ext4 ... not found 10191: libmount: CXT: [0x1a5d080]: /sbin/fs/mount.ext4 ... not found 10191: libmount: CXT: [0x1a5d080]: prepare update 10191: libmount: CXT: [0x1a5d080]: checking for writable tab files 10191: libmount: UTILS: mtab: /etc/mtab 10191: libmount: UTILS: /etc/mtab: irregular/non-writable 10191: libmount: UTILS: utab: /run/mount/utab 10191: libmount: UPDATE: [0x1a62270]: allocate 10191: libmount: UPDATE: [0x1a62270]: resetting FS [fs=0x0x1a5d180, target=(null), flags=0x00000000] 10191: libmount: UPDATE: [0x1a62270]: FS template: 10191: libmount: UPDATE: ------ fs: 0x1a5d180 source: /dev/md127 target: /disk/data fstype: ext4 optstr: rw VFS-optstr: rw 10191: libmount: UPDATE: prepare utab entry 10191: libmount: UPDATE: utab entry unnecessary (no options) 10191: libmount: CXT: [0x1a5d080]: mount: do mount 10191: libmount: CXT: [0x1a5d080]: mount(2) [source=/dev/md127, target=/disk/data, type=ext4, mountflags=0xc0ed0000, mountdata=<none>] [ 9023.111850] EXT4-fs (md127): mounted filesystem with ordered data mode. Opts: (null) 10191: libmount: CXT: [0x1a5d080]: mount(2) success 10191: libmount: CXT: [0x1a5d080]: don't update: no update prepared 10191: libmount: CXT: [0x1a5d080]: <---- reset [status=1] ----> 10191: libmount: FS: [0x1a5d180]: free [refcount=0] 10191: libmount: CACHE: [0x1a5d2c0]: free [refcount=0] 10191: libmount: UPDATE: [0x1a62270]: free 10191: libmount: CXT: [0x1a5d080]: <---- free Any ideas what could cause that? And just to repeat in sake of being clear, mounting to other destination directory works fine - even debug messages are practically identical. [1] dd if=/dev/zero bs=10M count=1 of=/dummy; mkfs.ext4 /dummy; mount /disk/data -- Sami Kerola http://www.iki.fi/kerolasa/ -- To unsubscribe from this list: send the line "unsubscribe util-linux" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
