After installing a fresh noble VM... I ran the repro code on the current and proposed kernel, the patch worked as intended. ``` :: Linux cap-noble 6.8.0-88-generic #89-Ubuntu SMP PREEMPT_DYNAMIC Sat Oct 11 01:02:46 UTC 2025 x86_64 x86_64 x86_64 GNU/Linux
[*] Current perf_event_paranoid level: 4. [*] This is a custom Ubuntu paranoid level. [*] Current capabilities: cap_perfmon=ep [!] CPU_CYCLES: Impossible to open perf event [!] INSTRUCTIONS: Impossible to open perf event [!] CACHE_REFERENCES: Impossible to open perf event Some events were not accessible with current capabilities :: Linux cap-noble 6.8.0-91-generic #92-Ubuntu SMP PREEMPT_DYNAMIC Fri Nov 28 16:26:35 UTC 2025 x86_64 x86_64 x86_64 GNU/Linux [*] Current perf_event_paranoid level: 4. [*] This is a custom Ubuntu paranoid level. [*] Current capabilities: cap_perfmon=ep [*] CPU_CYCLES: Successfully opened perf event [*] INSTRUCTIONS: Successfully opened perf event [*] CACHE_REFERENCES: Successfully opened perf event All perf events accessible with current capabilities ``` I also verfied that node_exporter exports perf metrics with cap_perfmon=ep under the new kernel but not on older kernels. ** Tags removed: verification-needed-noble-linux ** Tags added: verification-done-noble-linux -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2131046 Title: CAP_PERFMON insufficient to get perf data To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2131046/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
