devkit-disks-daemon/-helper spins upp sleeping disks

Binary package hint: devicekit-disks

Summary:
I have a sleeping disk that gets woken up periodically by devkit-disks-daemon.

I've investigated the issue like in https://bugs.launchpad.net/ubuntu/+source/hddtemp/+bug/160621 to assure this is not a duplicate of the before-mentioned.

System setup:
One SATA hard disk with /, /home etc., one EIDE disk (/dev/sdb) with an unmounted, not even mapped crypted filesystem.

Symptoms:
After sending the EIDE disk to standby or sleep (hdparm -y /dev/sdb or -Y respectivley) the drive spins down. However after some time it spins up again.

Investigation:
1. send the drive to sleep: "hdparm -Y /dev/sdb"
2. "btrace /dev/sdb > btrace.out" and "devkit-disks --monitor-detail > devkit-disks-monitor-detail.out" (see attachments for both files)
3. (wait some time)
4. I hear the spin-up-voice of the disk
5. I see the following records in the btrace log:
  8,16 0 0 0.000000000 0 m N cfq16873 alloced
  8,16 0 1 0.000000711 16873 G N [devkit-disks-he]
  8,16 0 2 0.000003731 16873 P N [devkit-disks-he]
  8,16 0 3 0.000003991 16873 I R 512 (85 08 2e 00 00 00 01 00 00 00 00 00 00 00 ec 00 ..) [devkit-disks-he]
  8,16 0 4 0.000004880 16873 D R 512 (85 08 2e 00 00 00 01 00 00 00 00 00 00 00 ec 00 ..) [devkit-disks-he]
6. (drive needs some seconds to spin up)
7. devkit-disks produces all the output found in the attached log file

Discussion:
It looks like "devkit-disks-he" wants to read data from the drive and thereby wakes it up. "devkit-disks-he" should be one of the "devkit-disks-helper-XXX" binaries located inside /usr/lib/devicekit-disks/ . I assume it to be called from the running devkit-disks-daemon.
  ps aux|grep devkit
  root 1650 0.0 0.0 47028 2784 ? S 17:27 0:00 /usr/lib/devicekit-power/devkit-power-daemon
  root 2699 0.0 0.0 50988 3412 ? S 17:27 0:01 /usr/lib/devicekit-disks/devkit-disks-daemon
  root 2700 0.0 0.0 42180 832 ? S 17:27 0:00 devkit-disks-daemon: polling /dev/sr0 /dev/sdc
The daemon should only poll /dev/sr0 and /dev/sdc (which is the very same hardware: the dvd drive).

ProblemType: Bug
Architecture: amd64
Date: Sun Apr 4 22:15:15 2010
DistroRelease: Ubuntu 9.10
InstallationMedia: Ubuntu 9.10 "Karmic Koala" - Release amd64 (20091027)
MachineType: System manufacturer System Product Name
NonfreeKernelModules: fglrx
Package: devicekit-disks 007-2ubuntu5
ProcCmdLine: BOOT_IMAGE=/boot/vmlinuz-2.6.31-20-generic root=UUID=5e1547d2-0376-4ad8-8f1c-ea170ffe4e43 ro quiet splash
ProcEnviron:
 PATH=(custom, user)
 LANG=sv_SE.UTF-8
 SHELL=/bin/bash
ProcVersionSignature: Ubuntu 2.6.31-20.58-generic
SourcePackage: devicekit-disks
Uname: Linux 2.6.31-20-generic x86_64
dmi.bios.date: 01/21/2010
dmi.bios.vendor: American Megatrends Inc.
dmi.bios.version: 2503
dmi.board.asset.tag: To Be Filled By O.E.M.
dmi.board.name: M4A78T-E
dmi.board.vendor: ASUSTeK Computer INC.
dmi.board.version: Rev 1.xx
dmi.chassis.asset.tag: Asset-1234567890
dmi.chassis.type: 3
dmi.chassis.vendor: Chassis Manufacture
dmi.chassis.version: Chassis Version
dmi.modalias: dmi:bvnAmericanMegatrendsInc.:bvr2503:bd01/21/2010:svnSystemmanufacturer:pnSystemProductName:pvrSystemVersion:rvnASUSTeKComputerINC.:rnM4A78T-E:rvrRev1.xx:cvnChassisManufacture:ct3:cvrChassisVersion:
dmi.product.name: System Product Name
dmi.product.version: System Version
dmi.sys.vendor: System manufacturer