Greeting,

FYI, we noticed the following commit (built with gcc-9):

commit: 6fd0d0deded94645d8cb96f93c26ad55cd92f6a5 ("[PATCH net-next] net: sch_generic: aviod concurrent reset and enqueue op for lockless qdisc")
url: https://github.com/0day-ci/linux/commits/Yunsheng-Lin/net-sch_generic-aviod-concurrent-reset-and-enqueue-op-for-lockless-qdisc/20200901-085941
base: https://git.kernel.org/cgit/linux/kernel/git/davem/net-next.git 10eb4667946068e34f0cde1485f030aa68c89275

in testcase: hwsim
version: hwsim-x86_64-6eb6cf0-1_20200619
with following parameters:

	group: hwsim-03
	ucode: 0x21



on test machine: 8 threads Intel(R) Core(TM) i7-3770K CPU @ 3.50GHz with 16G memory

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




If you fix the issue, kindly add following tag
Reported-by: kernel test robot <rong.a.chen@intel.com>



2020-09-05 21:47:27 	./run-tests.py ap_ht40_5ghz_switch 
DEV: wlan0: 02:00:00:00:00:00
DEV: wlan1: 02:00:00:00:01:00
DEV: wlan2: 02:00:00:00:02:00
APDEV: wlan3
APDEV: wlan4
START ap_ht40_5ghz_switch 1/1
Test: HT40 co-ex scan on 5 GHz switching pri/sec channel
Starting AP wlan4
Starting AP wlan3
Connect STA wlan0 to AP
wlan0: Country code not reset back to 00: is US
wlan0: Country code cleared back to 00
FAIL ap_ht40_5ghz_switch 3.614883 2020-09-05 21:47:31.016291
passed 0 test case(s)
skipped 0 test case(s)
failed tests: ap_ht40_5ghz_switch



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,
Rong Chen