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Jiri Olsa authored
[ Upstream commit 475113d9 ] It's possible to set up PEBS events to get only errors and not any data, like on SNB-X (model 45) and IVB-EP (model 62) via 2 perf commands running simultaneously: taskset -c 1 ./perf record -c 4 -e branches:pp -j any -C 10 This leads to a soft lock up, because the error path of the intel_pmu_drain_pebs_nhm() does not account event->hw.interrupt for error PEBS interrupts, so in case you're getting ONLY errors you don't have a way to stop the event when it's over the max_samples_per_tick limit: NMI watchdog: BUG: soft lockup - CPU#22 stuck for 22s! [perf_fuzzer:5816] ... RIP: 0010:[<ffffffff81159232>] [<ffffffff81159232>] smp_call_function_single+0xe2/0x140 ... Call Trace: ? trace_hardirqs_on_caller+0xf5/0x1b0 ? perf_cgroup_attach+0x70/0x70 perf_install_in_context+0x199/0x1b0 ? ctx_resched+0x90/0x90 SYSC_perf_event_open+0x641/0xf90 SyS_perf_event_open+0x9/0x1...
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