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[Bug 620455] Re: System time drifts when idle

 

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

** Changed in: linux (Ubuntu)
       Status: Incomplete => Expired

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Title:
  System time drifts when idle

Status in The Linux Kernel:
  Invalid
Status in “linux” package in Ubuntu:
  Expired

Bug description:
  It seems the system time stops when my notebook goes idle.
  By idle, I don't mean suspend or screen lock. But this is best described by the following script :

  #!/bin/bash
  # set hwclock to system clock to start
  # the log file with the same time
  hwclock -w
  #start with a fresh logfile
  touch clocktest.log
  echo START > clocktest.log
  while [[ true ]]
  do
   systime=$(date)
   hwtime=$(hwclock -r)
   echo "$systime | $hwtime" >> clocktest.log
   sleep 20
  done

  Expected output :
  On each line, the system time should be roughly the same. Time delta between each line should be
  around 20 seconds

  Observed output :
  Sorry for the 80 character column wrap. See the edited clocktest.log
  for a cleaner  ouput.
  Look at the following logfile :
  START
  jeudi 19 août 2010, 15:09:43 (UTC+0200) | jeu. 19 août 2010 15:09:44 CEST  -0.500555 secondes
  jeudi 19 août 2010, 15:10:04 (UTC+0200) | jeu. 19 août 2010 15:10:05 CEST  -1.001562 secondes
  jeudi 19 août 2010, 15:10:25 (UTC+0200) | jeu. 19 août 2010 15:10:26 CEST  -0.985944 secondes
  jeudi 19 août 2010, 15:10:46 (UTC+0200) | jeu. 19 août 2010 15:15:46 CEST  -0.032792 secondes <-- 5 minute lag !
  jeudi 19 août 2010, 15:11:06 (UTC+0200) | jeu. 19 août 2010 15:16:07 CEST  -0.985926 secondes
  jeudi 19 août 2010, 15:11:27 (UTC+0200) | jeu. 19 août 2010 15:16:28 CEST  -1.001539 secondes
  jeudi 19 août 2010, 15:11:48 (UTC+0200) | jeu. 19 août 2010 15:16:49 CEST  -0.985969 secondes
  jeudi 19 août 2010, 15:12:09 (UTC+0200) | jeu. 19 août 2010 15:17:10 CEST  -0.985977 secondes
  jeudi 19 août 2010, 15:12:30 (UTC+0200) | jeu. 19 août 2010 15:17:31 CEST  -1.001544 secondes
  jeudi 19 août 2010, 15:12:51 (UTC+0200) | jeu. 19 août 2010 15:17:52 CEST  -0.985920 secondes
  jeudi 19 août 2010, 15:13:12 (UTC+0200) | jeu. 19 août 2010 15:18:13 CEST  -0.985939 secondes
  jeudi 19 août 2010, 15:13:33 (UTC+0200) | jeu. 19 août 2010 15:18:34 CEST  -1.001581 secondes
  jeudi 19 août 2010, 15:13:54 (UTC+0200) | jeu. 19 août 2010 15:18:55 CEST  -0.985917 secondes
  jeudi 19 août 2010, 15:14:15 (UTC+0200) | jeu. 19 août 2010 15:29:15 CEST  -0.079685 secondes <-- add another 10 minute
  jeudi 19 août 2010, 15:14:35 (UTC+0200) | jeu. 19 août 2010 15:29:36 CEST  -1.001568 secondes
  jeudi 19 août 2010, 15:14:56 (UTC+0200) | jeu. 19 août 2010 15:29:57 CEST  -0.985952 secondes

  As you can see, after 20 minutes without touching the computer, the
  system time is late by 15 minutes.

  It did not happen with an ubuntu 8.04 kernel ie 2.6.24-28, so I said it was a regression when asked by ubuntu-bug
  It has indirect security consequences, because for example after these 20 minutes, I was still able to sudo without being asked
  for a password. Screen locking does not happen

  The script must be run with sudo because of hwclock

  This is an Amilo Xi 2550 notebook.

  WORKAROUND: processor.max_cstate=1

  WORKAROUND: nohz=off

  ProblemType: Bug
  DistroRelease: Ubuntu 10.04
  Package: linux-image-2.6.32-24-generic 2.6.32-24.39 [modified: lib/modules/2.6.32-24-generic/kernel/drivers/usb/serial/cp210x.ko]
  Regression: Yes
  Reproducible: Yes
  ProcVersionSignature: Ubuntu 2.6.32-24.39-generic 2.6.32.15+drm33.5
  Uname: Linux 2.6.32-24-generic i686
  AlsaVersion: Advanced Linux Sound Architecture Driver Version 1.0.21.
  Architecture: i386
  AudioDevicesInUse:
   USER        PID ACCESS COMMAND
   /dev/snd/controlC0:  cynove     1823 F.... pulseaudio
  CRDA: Error: command ['iw', 'reg', 'get'] failed with exit code 1:
  Card0.Amixer.info:
   Card hw:0 'Intel'/'HDA Intel at 0xf0800000 irq 22'
     Mixer name	: 'Realtek ALC883'
     Components	: 'HDA:10573055,10573055,00100700 HDA:10ec0883,17341238,00100002'
     Controls      : 29
     Simple ctrls  : 18
  Card1.Amixer.info:
   Card hw:1 'HDMI'/'HDA ATI HDMI at 0xcfeec000 irq 17'
     Mixer name	: 'ATI R6xx HDMI'
     Components	: 'HDA:1002aa01,00aa0100,00100000'
     Controls      : 5
     Simple ctrls  : 2
  Date: Thu Aug 19 15:23:03 2010
  HibernationDevice: RESUME=UUID=d8f0ebc9-37f3-4cdb-aca7-44a4bc42c13e
  MachineType: FUJITSU SIEMENS AMILO Xi 2550
  ProcCmdLine: root=UUID=d6f01bdd-8503-4992-bc4e-a511f74318fb ro quiet splash
  ProcEnviron:
   PATH=(custom, user)
   LANG=fr_FR.utf8
   SHELL=/bin/bash
  RelatedPackageVersions: linux-firmware 1.34.1
  SourcePackage: linux
  dmi.bios.date: 03/05/2008
  dmi.bios.vendor: Phoenix
  dmi.bios.version: 1.11C
  dmi.board.name: F44
  dmi.board.vendor: FUJITSU SIEMENS
  dmi.board.version: 00030D0055014B3C
  dmi.chassis.type: 10
  dmi.chassis.vendor: FUJITSU SIEMENS
  dmi.modalias: dmi:bvnPhoenix:bvr1.11C:bd03/05/2008:svnFUJITSUSIEMENS:pnAMILOXi2550:pvr:rvnFUJITSUSIEMENS:rnF44:rvr00030D0055014B3C:cvnFUJITSUSIEMENS:ct10:cvr:
  dmi.product.name: AMILO Xi 2550
  dmi.sys.vendor: FUJITSU SIEMENS

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