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[Brad Figg <brad.figg@xxxxxxxxxxxxx>]

This bug is missing log files that will aid in diagnosing the problem.
>From a terminal window please run:

apport-collect 1349028

and then change the status of the bug to 'Confirmed'.

If, due to the nature of the issue you have encountered, you are unable
to run this command, please add a comment stating that fact and change
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This change has been made by an automated script, maintained by the
Ubuntu Kernel Team.

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

** Tags added: saucy

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https://bugs.launchpad.net/bugs/1349028

Title:
  getitimer returns it_value=0 erroneously

Status in “linux” package in Ubuntu:
  Incomplete

Bug description:
  According to the 'getitimer()' man page: "The element it_value is set
  to the amount of time remaining on the timer, or zero if the  timer is
  disabled.  Similarly, it_interval is set to the reset value."

  As such the following Perl program should never exit:

      use Time::HiRes;
      $SIG{VTALRM} = sub { };
      Time::HiRes::setitimer(&Time::HiRes::ITIMER_VIRTUAL, 0.5, 0.4);
      while (1) {
          my @t = Time::HiRes::getitimer(&Time::HiRes::ITIMER_VIRTUAL);
          exit 0 if $t[0] == 0;
      }

  and on linux-image 3.11.0-18-generic (and all other systems tested) it
  loops forever but 3.13.0-32-generic it exits.  Have not bisected
  between those kernels, nor am I likely to be able to do so soon.

  This Perl program shows the timer countdown:

  use Time::HiRes;
  my $r = [Time::HiRes::gettimeofday()];
  sub display {
      my ($desc) = @_;
      my @t = Time::HiRes::getitimer(&Time::HiRes::ITIMER_VIRTUAL);
      my $i = Time::HiRes::tv_interval($r);
      printf "%s: elasped=%.8f; time left=%.6f reset time=%.6f\n", $desc,
      $i,@t;
  }
  $SIG{VTALRM} = sub {
      display('VTALRM');
      exit;
  };
  Time::HiRes::setitimer(&Time::HiRes::ITIMER_VIRTUAL, 0.5, 0.4);
  while (1) {
      display('inloop');
  }

  on other (working) systems it gives:

  inloop: elasped=1.65178400; time left=0.001000 reset time=0.401000
  inloop: elasped=1.65184200; time left=0.001000 reset time=0.401000
  inloop: elasped=1.65186800; time left=0.001000 reset time=0.401000
  inloop: elasped=1.65192300; time left=0.001000 reset time=0.401000
  inloop: elasped=1.65198100; time left=0.001000 reset time=0.401000
  VTALRM: elasped=1.65209800; time left=0.400000 reset time=0.401000
  (end of file)

  but on the 3.13.0-32-generic or later kernel I get:

  inloop: elasped=0.54692100; time left=0.000033 reset time=0.400000
  inloop: elasped=0.54692800; time left=0.000026 reset time=0.400000
  inloop: elasped=0.54693500; time left=0.000020 reset time=0.400000
  inloop: elasped=0.54694100; time left=0.000013 reset time=0.400000
  inloop: elasped=0.54694800; time left=0.000007 reset time=0.400000
  inloop: elasped=0.54695500; time left=0.000000 reset time=0.400000
  inloop: elasped=0.54696200; time left=0.004000 reset time=0.400000
  [...]
  VTALRM: elasped=0.55013600; time left=0.397062 reset time=0.400000
  (end of file)

  The reset time also looks dodgy.

  Hardware is an Intel Core i7-920 on Asus P6T Deluxe v2 (X58)
  motherboard and hasn't changed.

  
  Requested information:

  Ubuntu 3.13.0-32.57-generic 3.13.11.4

  Description:	Ubuntu 14.04.1 LTS
  Release:	14.04

  # apt-cache policy linux-image-generic
  linux-image-generic:
    Installed: 3.13.0.32.38
    Candidate: 3.13.0.32.38
    Version table:
   *** 3.13.0.32.38 0
          500 http://us.archive.ubuntu.com/ubuntu/ trusty-updates/main amd64 Packages
          500 http://us.archive.ubuntu.com/ubuntu/ trusty-security/main amd64 Packages
          500 http://us.archive.ubuntu.com/ubuntu/ trusty-proposed/main amd64 Packages
          500 http://ppa.launchpad.net/canonical-kernel-team/ppa/ubuntu/ trusty/main amd64 Packages
          100 /var/lib/dpkg/status
       3.13.0.24.28 0
          500 http://us.archive.ubuntu.com/ubuntu/ trusty/main amd64 Packages

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