FYI, we noticed the following commit (built with gcc-7):

commit: 02a5c550b2738f2bfea8e1e00aa75944d71c9e18 ("rcu: Abstract extended quiescent state determination")
https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git master

in testcase: perf_event_tests
with following parameters:

	paranoid: disallow_kernel_profiling

test-description: The Perf Event Testsuite.
test-url: https://github.com/deater/perf_event_tests


on test machine: qemu-system-x86_64 -enable-kvm -cpu host -smp 2 -m 2G

caused below changes (please refer to attached dmesg/kmsg for entire log/backtrace):


+-------------------------------------------------+------------+------------+
|                                                 | 2625d469ba | 02a5c550b2 |
+-------------------------------------------------+------------+------------+
| boot_successes                                  | 18         | 0          |
| boot_failures                                   | 0          | 17         |
| BUG:kernel_reboot-without-warning_in_test_stage | 0          | 17         |
+-------------------------------------------------+------------+------------+



[   21.715217] 
[   22.950524] perf: interrupt took too long (5334 > 5235), lowering kernel.perf_event_max_sample_rate to 37250
[   22.956921] perf: interrupt took too long (6735 > 6667), lowering kernel.perf_event_max_sample_rate to 29500
[   22.970150] perf: interrupt took too long (8494 > 8418), lowering kernel.perf_event_max_sample_rate to 23500
[   22.976586] perf: interrupt took too long (10754 > 10617), lowering kernel.perf_event_max_sample_rate to 18500
BUG: kernel reboot-without-warning in test stage

Elapsed time: 30

#!/bin/bash



To reproduce:

        git clone https://github.com/intel/lkp-tests.git
        cd lkp-tests
        bin/lkp qemu -k <bzImage> job-script # job-script is attached in this email



Thanks,
lkp