Greeting,

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

commit: 1c04296f8fb2ab3c350c5889f8ac58f1690cd19c ("[PATCH v4] sysfs: fix kobject refcount to address races with kobject removal")
url: https://github.com/0day-ci/linux/commits/Luis-Chamberlain/sysfs-fix-kobject-refcount-to-address-races-with-kobject-removal/20210624-055134
base: https://git.kernel.org/cgit/linux/kernel/git/gregkh/driver-core.git 09705dcb63d269000595284b5dd7f5c938d647b9

in testcase: suspend-stress
version: 
with following parameters:

	mode: mem
	iterations: 10



on test machine: 4 threads Ivy Bridge with 4G 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 <oliver.sang@intel.com>

SUSPEND RESUME TEST STARTED
Suspend to mem 1/10:
/usr/bin/wget -q --timeout=1800 --tries=1 --local-encoding=UTF-8 http://internal-lkp-server:80/~lkp/cgi-bin/lkp-jobfile-append-var?job_file=/lkp/jobs/scheduled/lkp-ivb-toshiba1/suspend-stress-10-mem-debian-x86_64-20180403.cgz-1c04296f8fb2ab3c350c5889f8ac58f1690cd19c-20210628-95711-737wjl-19.yaml&job_state=suspending-1/10 -O /dev/null
Failed



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 split-job --compatible job.yaml  # generate the yaml file for lkp run
        bin/lkp run                    generated-yaml-file



---
0DAY/LKP+ Test Infrastructure                   Open Source Technology Center
https://lists.01.org/hyperkitty/list/lkp@lists.01.org       Intel Corporation

Thanks,
Oliver Sang