This was fixed in 6.8.1-1006.6 realtime on Noble and 5.15.0-1068.76 realtime on Jammy.
** Changed in: ubuntu-realtime Status: Fix Committed => Fix Released ** Changed in: linux-realtime (Ubuntu) Status: Fix Committed => Fix Released ** Changed in: linux-realtime (Ubuntu Jammy) Status: Fix Committed => Fix Released ** Changed in: linux-realtime (Ubuntu Noble) Status: Fix Committed => Fix Released -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux-realtime in Ubuntu. https://bugs.launchpad.net/bugs/2071853 Title: Disable DEBUG_PREEMPT in jammy and noble realtime kernels Status in ubuntu-realtime: Fix Released Status in linux-realtime package in Ubuntu: Fix Released Status in linux-realtime source package in Jammy: Fix Released Status in linux-realtime source package in Noble: Fix Released Bug description: SRU Justification: [Impact] CONFIG_DEBUG_PREEMPT was accidentally enabled on jammy last year as part of 5.15.0-1040.45 when we migrated to annotations for kernel configs. It was also copied into the noble realtime kernel. This config can introduce additional latency. More info on this config is at https://cateee.net/lkddb/web-lkddb/DEBUG_PREEMPT.html [Fix] CONFIG_DEBUG_PREEMPT should be disabled on both jammy and noble. [Test Plan] We will use our kernel regression testing to confirm this doesn't cause any regressions. This will include cyclictest and other latency tests. [Where problems could occur] This change is limited. If code elsewhere inadvertently depends on this additional latency, it could cause a problem. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu-realtime/+bug/2071853/+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