Hibernate causes an unmounted hard drive in sleep mode to spin up

[b3nmore]

I've got a hdd for backups, which most of the time is unmounted and sleeping (spun down). When going into hibernation it spins up shortly before the computer powers off. This is somehow annoying because it's noisy, elongates the power off process and is completely senseless.
Syslog shows: "kernel: [ ...] Synchronizing SCSI cache" for all my hdd when going into hibernation. Thats the only hint I've got so far whats causing the wakeup.
This happens in oneiric and precise (pm-utils 1.4.1-8ubuntu1 and 1.4.1-9). Btw it does not happen when suspending.

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ApportVersion: 2.16.2-0ubuntu3
Architecture: amd64
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC0: kiran 1524 F.... pulseaudio
CurrentDesktop: XFCE
DistroRelease: Ubuntu 15.04
HibernationDevice: RESUME=UUID=ebcf26a9-f63a-4b55-ad87-31f7b1f3feb6
InstallationDate: Installed on 2015-03-14 (0 days ago)
InstallationMedia: Xubuntu 15.04 "Vivid Vervet" - Alpha amd64 (20150313)
MachineType: LENOVO 2767WSD
Package: linux (not installed)
PccardctlIdent:
 Socket 0:
   no product info available
PccardctlStatus:
 Socket 0:
   no card
ProcFB: 0 inteldrmfb
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.19.0-9-generic root=UUID=f0d3de75-e584-48c4-a3af-7b73dd5eb495 ro quiet splash
ProcVersionSignature: Ubuntu 3.19.0-9.9-generic 3.19.1
RelatedPackageVersions:
 linux-restricted-modules-3.19.0-9-generic N/A
 linux-backports-modules-3.19.0-9-generic N/A
 linux-firmware 1.143
RfKill:
 0: phy0: Wireless LAN
  Soft blocked: no
  Hard blocked: no
Tags: vivid
UdevLog: Error: [Errno 2] No such file or directory: '/var/log/udev'
Uname: Linux 3.19.0-9-generic x86_64
UpgradeStatus: No upgrade log present (probably fresh install)
UserGroups: adm cdrom dip lpadmin plugdev sambashare sudo
_MarkForUpload: True
dmi.bios.date: 10/17/2012
dmi.bios.vendor: LENOVO
dmi.bios.version: 7UET94WW (3.24 )
dmi.board.name: 2767WSD
dmi.board.vendor: LENOVO
dmi.board.version: Not Available
dmi.chassis.asset.tag: No Asset Information
dmi.chassis.type: 10
dmi.chassis.vendor: LENOVO
dmi.chassis.version: Not Available
dmi.modalias: dmi:bvnLENOVO:bvr7UET94WW(3.24):bd10/17/2012:svnLENOVO:pn2767WSD:pvrThinkPadT400:rvnLENOVO:rn2767WSD:rvrNotAvailable:cvnLENOVO:ct10:cvrNotAvailable:
dmi.product.name: 2767WSD
dmi.product.version: ThinkPad T400
dmi.sys.vendor: LENOVO

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[penalvch (penalvch)]

b3nmore, could you please execute the following via a terminal in order for the necessary debugging information to be attached:
apport-collect 980307

[b3nmore (b3nmore)]

apport information

[Launchpad Janitor (janitor)]

[Expired for linux (Ubuntu) because there has been no activity for 60 days.]

[b3nmore (b3nmore)]

Last apport-collect was on utopic, but this is still an issue with vivid (kernel 3.19).

Btw this might be a dup of https://bugs.launchpad.net/ubuntu/+source/linux/+bug/524407

[b3nmore (b3nmore)]

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[b3nmore (b3nmore)]

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[b3nmore (b3nmore)]

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[b3nmore (b3nmore)]

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[b3nmore (b3nmore)]

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[b3nmore (b3nmore)]

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[b3nmore (b3nmore)]

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[b3nmore (b3nmore)]

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[b3nmore (b3nmore)]

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[b3nmore (b3nmore)]

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[b3nmore (b3nmore)]

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[b3nmore (b3nmore)]

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[b3nmore (b3nmore)]

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[penalvch (penalvch)]

b3nmore, could you please test the latest upstream kernel available from the very top line at the top of the page (the release names are irrelevant for testing, and please do not test the daily folder) following https://wiki.ubuntu.com/KernelMainlineBuilds ? It will allow additional upstream developers to examine the issue.

If the test did not allow you to test to the issue (ex. you couldn't boot into the OS) please make a comment in your report about this, and continue to test the next most recent kernel version until you can test to the issue. Once you've tested the upstream kernel, please comment on which kernel version specifically you tested. If this bug is fixed in the mainline kernel, please add the following tags by clicking on the yellow circle with a black pencil icon, next to the word Tags, located at the bottom of the report description:
kernel-fixed-upstream
kernel-fixed-upstream-3.XY-rcZ

Where XY and Z are numbers corresponding to the kernel version.

If the mainline kernel does not fix this bug, please add the following tags:
kernel-bug-exists-upstream
kernel-bug-exists-upstream-3.XY-rcZ

Once testing of the upstream kernel is complete, please mark this bug's Status as Confirmed. Please let us know your results.

Thank you for your understanding.

[penalvch (penalvch)]

b3nmore, does this also happen when the computer shuts down?

[b3nmore (b3nmore)]

> b3nmore, does this also happen when the computer shuts down?

Yes, its basically the same for shutdown and hibernation: At the very end of the shutdown/hibernation process, when one would expect the system to power off, the drive spins up and then the system powers off.

[penalvch (penalvch)]

b3nmore, at this point, the phenomenon reported appears expected and normal.

If something resides in memory, it would naturally need to be flushed to disk before hibernating was to be concluded, otherwise that data in memory would be gone when the computer turns off. One would expect the same thing to happen in any operating system.

Hence, unless there is something patently wrong here, this isn't a bug at all, but expected.

[b3nmore (b3nmore)]

For the sake of completeness, the point is, that we're talking about a hdd with no mounted partitions. As far as I understand it, any data, which might be in memory needs to be flushed before unmounting (after all you don't loose data when disconnecting an unmounted usb flash drive).

Anyhow, this is definitively a duplicate of https://bugs.launchpad.net/ubuntu/+source/linux/+bug/524407, which contains also a reference to an upstream report. So marking this one accordingly.