FYI, we noticed the following commit: commit: a5df70c354c26e20d5fd8eb64517f724e97ef0b2 ("perf/x86: Only show format attributes when supported") https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git master in testcase: perf-sanity-tests with following parameters: on test machine: 72 threads Intel(R) Xeon(R) CPU E5-2699 v3 @ 2.30GHz with 128G memory caused below changes (please refer to attached dmesg/kmsg for entire log/backtrace): 2017-09-22 14:03:03 sudo /usr/src/linux-perf-x86_64-rhel-7.2-a5df70c354c26e20d5fd8eb64517f724e97ef0b2/tools/perf/perf test 5 5: Test data source output : Ok 2017-09-22 14:03:03 sudo /usr/src/linux-perf-x86_64-rhel-7.2-a5df70c354c26e20d5fd8eb64517f724e97ef0b2/tools/perf/perf test 6 6: Parse event definition strings : FAILED! 2017-09-22 14:03:03 sudo /usr/src/linux-perf-x86_64-rhel-7.2-a5df70c354c26e20d5fd8eb64517f724e97ef0b2/tools/perf/perf test 7 To reproduce: git clone https://github.com/intel/lkp-tests.git cd lkp-tests bin/lkp install job.yaml # job file is attached in this email bin/lkp run job.yaml Thanks, Xiaolong