** Description changed: - The focal kernel is failing the ubuntu_ltp:sched:time-schedule01 and - ubuntu_ltp:sched:trace_sched01 regression test due to sched_setscheduler - being unable to a task class to SCHED_FIFO. + [SRU Justification] + + [Impact] + The focal kernel is failing the ubuntu_ltp:sched:time-schedule01 and ubuntu_ltp:sched:trace_sched01 regression test due to sched_setscheduler being unable to a task class to SCHED_FIFO. This is due to have having CONFIG_RT_GROUP_SCHED enabled. There are multiple known issues with CONFIG_RT_GROUP_SCHED that are reported in the debian.master/config/annotations file: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1284731 https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1873315 https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1875665 - We do not have a good reason to enable this , I see no processes using realtime scheduling. We should disable this setting to match the upstream Ubuntu focal arm64 kernel. The following tests are failing with this error: - * ubuntu_ltp:sched:time-schedule01 - * ubuntu_ltp:sched:trace_sched01 - * ubuntu_qrt_apparmor:test-apparmor + [Fix] + + CONFIG_RT_GROUP_SCHED should be disabled. The config was enabled when we + copied the Xilinx default config settings and there is not a + justification for this exact config. + + [Testcase]
-- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux-xilinx-zynqmp in Ubuntu. https://bugs.launchpad.net/bugs/1992912 Title: linux-xilinx-zynqmp/focal: main(): sched_setscheduler(): Operation not permitted Status in ubuntu-kernel-tests: New Status in linux-xilinx-zynqmp package in Ubuntu: New Bug description: [SRU Justification] [Impact] The focal kernel is failing the ubuntu_ltp:sched:time-schedule01 and ubuntu_ltp:sched:trace_sched01 regression test due to sched_setscheduler being unable to a task class to SCHED_FIFO. This is due to have having CONFIG_RT_GROUP_SCHED enabled. There are multiple known issues with CONFIG_RT_GROUP_SCHED that are reported in the debian.master/config/annotations file: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1284731 https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1873315 https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1875665 [Fix] CONFIG_RT_GROUP_SCHED should be disabled. The config was enabled when we copied the Xilinx default config settings and there is not a justification for this exact config. There may even be a negative impact, from the kernel.org documentation: “The default values for sched_rt_period_us (1000000 or 1s) and sched_rt_runtime_us (950000 or 0.95s). This gives 0.05s to be used by SCHED_OTHER (non-RT tasks).” This suggests this option will benefit RT systems, but be detrimental to non-RT systems, [Testcase] The annotations file will enforce that CONFIG_RT_GROUP_SCHED is disabled. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu-kernel-tests/+bug/1992912/+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
