apport information ** Attachment added: "BootDmesg.txt" https://bugs.launchpad.net/bugs/1349028/+attachment/4163588/+files/BootDmesg.txt
-- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1349028 Title: getitimer returns it_value=0 erroneously Status in “linux” package in Ubuntu: Confirmed 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 --- ApportVersion: 2.14.1-0ubuntu3.2 Architecture: amd64 AudioDevicesInUse: USER PID ACCESS COMMAND /dev/snd/controlC1: tivrusky 3009 F.... pulseaudio /dev/snd/controlC0: tivrusky 3009 F.... pulseaudio DistroRelease: Ubuntu 14.04 HibernationDevice: RESUME=UUID=c026abdc-9fee-425c-b5ae-020bf6ea2ad6 IwConfig: eth0 no wireless extensions. eth1 no wireless extensions. lo no wireless extensions. MachineType: System manufacturer System Product Name Package: linux (not installed) ProcFB: 0 radeondrmfb ProcKernelCmdLine: root=UUID=3ea7a4cb-eade-4906-b545-5133d8c14080 ro quiet splash ProcVersionSignature: Ubuntu 3.13.0-32.57-generic 3.13.11.4 RelatedPackageVersions: linux-restricted-modules-3.13.0-32-generic N/A linux-backports-modules-3.13.0-32-generic N/A linux-firmware 1.127.5 RfKill: 0: hci0: Bluetooth Soft blocked: no Hard blocked: no Tags: trusty Uname: Linux 3.13.0-32-generic x86_64 UpgradeStatus: Upgraded to trusty on 2014-06-10 (46 days ago) UserGroups: adm admin cdrom dialout lpadmin mythtv plugdev sambashare vboxusers WifiSyslog: Jul 26 20:23:08 zwei NetworkManager[1174]: <info> Policy set 'Wired connection 2' (eth1) as default for IPv6 routing and DNS. WpaSupplicantLog: _MarkForUpload: True dmi.bios.date: 02/04/2009 dmi.bios.vendor: American Megatrends Inc. dmi.bios.version: 0203 dmi.board.asset.tag: To Be Filled By O.E.M. dmi.board.name: P6T DELUXE V2 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.:bvr0203:bd02/04/2009:svnSystemmanufacturer:pnSystemProductName:pvrSystemVersion:rvnASUSTeKComputerINC.:rnP6TDELUXEV2:rvrRev1.xx:cvnChassisManufacture:ct3:cvrChassisVersion: dmi.product.name: System Product Name dmi.product.version: System Version dmi.sys.vendor: System manufacturer To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1349028/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
