Hi Liam,

We caught a "task blocked" dmesg in maple tree test. Not sure if this
is expected for maple tree test, so we are sending this report for
your information. Thanks.

Greeting,

FYI, we noticed INFO:task_blocked_for_more_than#seconds due to commit (built with clang-14):

commit: 120b116208a0877227fc82e3f0df81e7a3ed4ab1 ("maple_tree: reorganize testing to restore module testing")
https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git master

in testcase: boot

on test machine: qemu-system-x86_64 -enable-kvm -cpu SandyBridge -smp 2 -m 16G

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


[   17.318428][    T1] calling  maple_tree_seed+0x0/0x15d0 @ 1
[   17.319219][    T1] 
[   17.319219][    T1] TEST STARTING
[   17.319219][    T1] 
[  999.249871][   T23] INFO: task rcu_scale_shutd:59 blocked for more than 491 seconds.
[  999.253363][   T23]       Not tainted 6.1.0-rc4-00003-g120b116208a0 #1
[  999.254249][   T23] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[  999.255390][   T23] task:rcu_scale_shutd state:D stack:30968 pid:59    ppid:2      flags:0x00004000
[  999.256934][   T23] Call Trace:
[  999.257418][   T23]  <TASK>
[  999.257900][   T23]  __schedule+0x169b/0x1f90
[  999.261677][   T23]  schedule+0x151/0x300
[  999.262281][   T23]  ? compute_real+0xe0/0xe0
[  999.263364][   T23]  rcu_scale_shutdown+0xdd/0x130
[  999.264093][   T23]  ? wake_bit_function+0x2c0/0x2c0
[  999.268985][   T23]  kthread+0x309/0x3a0
[  999.269958][   T23]  ? compute_real+0xe0/0xe0
[  999.270552][   T23]  ? kthread_unuse_mm+0x200/0x200
[  999.271281][   T23]  ret_from_fork+0x1f/0x30
[  999.272385][   T23]  </TASK>
[  999.272865][   T23] 
[  999.272865][   T23] Showing all locks held in the system:
[  999.273988][   T23] 2 locks held by swapper/0/1:
[  999.274684][   T23] 1 lock held by khungtaskd/23:
[  999.275400][   T23]  #0: ffffffff88346e00 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x8/0x30
[  999.277171][   T23] 
[  999.277525][   T23] =============================================
[  999.277525][   T23] 
[ 1049.050884][    T1] maple_tree: 12610686 of 12610686 tests passed


If you fix the issue, kindly add following tag
| Reported-by: kernel test robot <yujie.liu@intel.com>
| Link: https://lore.kernel.org/oe-lkp/202301310940.4a37c7af-yujie.liu@intel.com


To reproduce:

        # build kernel
	cd linux
	cp config-6.1.0-rc4-00003-g120b116208a0 .config
	make HOSTCC=clang-14 CC=clang-14 ARCH=x86_64 olddefconfig prepare modules_prepare bzImage modules
	make HOSTCC=clang-14 CC=clang-14 ARCH=x86_64 INSTALL_MOD_PATH=<mod-install-dir> modules_install
	cd <mod-install-dir>
	find lib/ | cpio -o -H newc --quiet | gzip > modules.cgz


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

        # if come across any failure that blocks the test,
        # please remove ~/.lkp and /lkp dir to run from a clean state.


-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests