This was fixed in the following linux versions: Ubuntu-3.2.0-59.90 Ubuntu-3.5.0-47.71 Ubuntu-lts-3.8.0-37.53 Ubuntu-3.11.0-17.31 Ubuntu-3.13.0-0.2
** Changed in: linux (Ubuntu Precise) Status: In Progress => Fix Released ** Changed in: linux (Ubuntu Quantal) Status: In Progress => Fix Released ** Changed in: linux (Ubuntu Saucy) Status: In Progress => Fix Released ** Changed in: linux (Ubuntu Trusty) Status: In Progress => Fix Released ** Also affects: linux-lts-raring (Ubuntu) Importance: Undecided Status: New ** Changed in: linux (Ubuntu Raring) Status: In Progress => Won't Fix ** No longer affects: linux-lts-raring (Ubuntu Quantal) ** No longer affects: linux-lts-raring (Ubuntu Raring) ** No longer affects: linux-lts-raring (Ubuntu Saucy) ** No longer affects: linux-lts-raring (Ubuntu Trusty) ** Changed in: linux-lts-raring (Ubuntu) Status: New => Invalid ** Changed in: linux-lts-raring (Ubuntu Precise) Status: New => Fix Released ** Changed in: linux-lts-raring (Ubuntu Precise) Assignee: (unassigned) => Chris J Arges (arges) ** Changed in: linux-lts-raring (Ubuntu Precise) Importance: Undecided => Medium -- 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/1259645 Title: cgroup cpu capping via cpu.cfs_quota can cause tasks to not be scheduled on the runque Status in “linux” package in Ubuntu: Fix Released Status in “linux-lts-raring” package in Ubuntu: Invalid Status in “linux” source package in Precise: Fix Released Status in “linux-lts-raring” source package in Precise: Fix Released Status in “linux” source package in Quantal: Fix Released Status in “linux” source package in Raring: Won't Fix Status in “linux” source package in Saucy: Fix Released Status in “linux” source package in Trusty: Fix Released Bug description: SRU Justification: Impact: When using cgroup's cpu capping features via the cpu.cfs_quota setting a race condition can occur such that a task has its timer disabled and no longer gets scheduled on the runqueue. This has been observed when setting cgroup cpu capping on VMs started and restarted with libvirt. Fix: Commit f9f9ffc237dd924f048204e8799da74f9ecf40cf upstream fixes this issue. It fixes throttle_cfs_rq by checking if the timer is not active. If it isn't then it calls __start_cfs_bandwidth which will put the task back on the runqueue. Testcase: From the patch: make a run/sleep task in a cgroup, loop switching the cgroup between 1ms/100ms quota and unlimited, checking for timer_active=0 and throttled=1 as a failure. With the throttle_cfs_rq() change commented out this fails, with the full patch it passes. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1259645/+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