[linus:master] [treewide] b04e317b52: INFO:task_blocked_for_more_than#seconds

[kernel test robot <oliver.sang@intel.com>]

Hello,


we noticed the issue happens with a low rate on this commit, but keeps clean
on parent when we even run the tests up to 999 times. just FYI.

41f70d8e16349c65 b04e317b522630b46f78ee62ecb
---------------- ---------------------------
       fail:runs  %reproduction    fail:runs
           |             |             |
           :999          2%          16:999   dmesg.INFO:task_blocked_for_more_than#seconds
           :999          2%          16:999   dmesg.Kernel_panic-not_syncing:hung_task:blocked_tasks


kernel test robot noticed "INFO:task_blocked_for_more_than#seconds" on:

commit: b04e317b522630b46f78ee62ecbdc5734e8d43de ("treewide: Introduce kthread_run_worker[_on_cpu]()")
https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git master

[test failed on linus/master      7ee983c850b40043ac4751836fbd9a2b4d0c5937]
[test failed on linux-next/master ed58d103e6da15a442ff87567898768dc3a66987]

in testcase: rcuscale
version: 
with following parameters:

	runtime: 300s
	scale_type: rcu



config: i386-randconfig-052-20250205
compiler: gcc-12
test machine: qemu-system-x86_64 -enable-kvm -cpu SandyBridge -smp 2 -m 16G

(please refer to attached dmesg/kmsg for entire log/backtrace)



If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <oliver.sang@intel.com>
| Closes: https://lore.kernel.org/oe-lkp/202502121025.55bfa801-lkp@intel.com


[ 1023.501569][   T32] INFO: task UVCG:82 blocked for more than 491 seconds.
[ 1023.510932][   T32]       Tainted: G                T  6.13.0-rc2-00014-gb04e317b5226 #1
[ 1023.528506][   T32] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[ 1023.551252][   T32] task:UVCG            state:D stack:0     pid:82    tgid:82    ppid:2      flags:0x00004000
[ 1023.582336][   T32] Call Trace:
[ 1023.599286][ T32] __schedule (kernel/sched/core.c:5372 kernel/sched/core.c:6756) 
[ 1023.617204][ T32] ? __this_cpu_preempt_check (lib/smp_processor_id.c:67) 
[ 1023.637326][ T32] schedule (kernel/sched/core.c:6834 kernel/sched/core.c:6848) 
[ 1023.653175][ T32] schedule_preempt_disabled (kernel/sched/core.c:6906) 
[ 1023.672095][ T32] kthread (kernel/kthread.c:453) 
[ 1023.684220][ T32] ? kthread_flush_work (kernel/kthread.c:970) 
[ 1023.700611][ T32] ? kthread_is_per_cpu (kernel/kthread.c:413) 
[ 1023.716756][ T32] ret_from_fork (arch/x86/kernel/process.c:153) 
[ 1023.732758][ T32] ? kthread_is_per_cpu (kernel/kthread.c:413) 
[ 1023.748605][ T32] ret_from_fork_asm (arch/x86/entry/entry_32.S:737) 
[ 1023.764004][ T32] entry_INT80_32 (arch/x86/entry/entry_32.S:942) 
[ 1023.776959][   T32]
[ 1023.776959][   T32] Showing all locks held in the system:
[ 1023.803410][   T32] 1 lock held by khungtaskd/32:
[ 1023.815913][ T32] #0: c3baa3d4 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire (include/linux/rcupdate.h:336) 
[ 1023.842061][   T32] 1 lock held by in:imklog/227:
[ 1023.849815][ T32] #0: ecd0e884 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos (fs/file.c:1194) 
[ 1023.877481][   T32] 1 lock held by dmesg/494:
[ 1023.885260][   T32] 2 locks held by depmod/567:
[ 1023.903871][   T32]
[ 1023.907007][   T32] =============================================
[ 1023.907007][   T32]
[ 1023.938278][   T32] Kernel panic - not syncing: hung_task: blocked tasks
[ 1023.951013][   T32] CPU: 0 UID: 0 PID: 32 Comm: khungtaskd Tainted: G                T  6.13.0-rc2-00014-gb04e317b5226 #1 78ab3595737b7bb7ccfbfed5c1dcb65e25af99a7
[ 1023.973770][   T32] Tainted: [T]=RANDSTRUCT
[ 1023.979010][   T32] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
[ 1023.991787][   T32] Call Trace:
[ 1023.995862][ T32] dump_stack_lvl (lib/dump_stack.c:122) 
[ 1024.001535][ T32] dump_stack (lib/dump_stack.c:130) 
[ 1024.006622][ T32] panic (kernel/panic.c:258 kernel/panic.c:375) 
[ 1024.011360][ T32] check_hung_uninterruptible_tasks (kernel/hung_task.c:239) 
[ 1024.018678][ T32] watchdog (kernel/hung_task.c:398) 
[ 1024.023798][ T32] kthread (kernel/kthread.c:466) 
[ 1024.028697][ T32] ? check_hung_uninterruptible_tasks (kernel/hung_task.c:380) 
[ 1024.036601][ T32] ? kthread_is_per_cpu (kernel/kthread.c:413) 
[ 1024.042763][ T32] ret_from_fork (arch/x86/kernel/process.c:153) 
[ 1024.048431][ T32] ? kthread_is_per_cpu (kernel/kthread.c:413) 
[ 1024.054588][ T32] ret_from_fork_asm (arch/x86/entry/entry_32.S:737) 
[ 1024.060422][ T32] entry_INT80_32 (arch/x86/entry/entry_32.S:942) 
[ 1024.067908][   T32] Kernel Offset: disabled



The kernel config and materials to reproduce are available at:
https://download.01.org/0day-ci/archive/20250212/202502121025.55bfa801-lkp@intel.com



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