[linus:master] [sched/fair] 4823725d9d: INFO:task_blocked_for_more_than#seconds

[linus:master] [sched/fair] 4823725d9d: INFO:task_blocked_for_more_than#seconds

[kernel test robot]

Hello,


for this change "sched/fair: Increase weight bits for avg_vruntime", we reported
"[peterz-queue:sched/hrtick] [sched/fair]  fb047eb995: Oops:general_protection_fault,probably_for_non-canonical_address#:#[##]KASAN_PTI"
in [1]

but we cannot reproduce the issue in [1] now with same tests and the same
x86_64-randconfig as the kbuild input config for 4823725d9d.

however, with another i386-randconfig in boot tests, we found some random
issues for this change which are clean on parent.

=========================================================================================
tbox_group/testcase/rootfs/kconfig/compiler/sleep:
  vm-snb/boot/yocto-i386-minimal-20190520.cgz/i386-randconfig-2006-20250804/gcc-14/1

9fe89f022c05d99c 4823725d9d1d9cc5b36647e0cb8
---------------- ---------------------------
       fail:runs  %reproduction    fail:runs
           |             |             |
           :499         13%          64:499   last_state.booting
           :499          6%          29:499   dmesg.BUG:kernel_hang_in_boot_stage
           :499          7%          33:499   dmesg.BUG:workqueue_lockup-pool
           :499          0%           1:499   dmesg.EIP:_raw_spin_unlock_irqrestore
           :499          1%           3:499   dmesg.EIP:finish_task_switch
           :499          0%           1:499   dmesg.EIP:handle_softirqs
           :499          0%           2:499   dmesg.EIP:lock_acquire
           :499          0%           1:499   dmesg.EIP:lock_release
           :499          0%           1:499   dmesg.EIP:on_each_cpu_cond_mask
           :499          0%           1:499   dmesg.EIP:rcu_preempt_deferred_qs_irqrestore
           :499          1%           3:499   dmesg.INFO:rcu_preempt_detected_stalls_on_CPUs/tasks
           :499          3%          14:499   dmesg.INFO:task_blocked_for_more_than#seconds

below full report is for "dmesg.INFO:task_blocked_for_more_than#seconds",
if you need more information, please let us know. thanks!

[1] https://lore.kernel.org/all/202602032236.bcc0d1b7-lkp@intel.com/



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

commit: 4823725d9d1d9cc5b36647e0cb8ff616cad6536f ("sched/fair: Increase weight bits for avg_vruntime")
https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git master

[test failed on linus/master      f1a5e78a55ebf2b05777fd5eb738038ddae609d6]
[test failed on linux-next/master b9303e6bff706758c167af686b5315ad00233bf8]
[test failed on fix commit        556146ce5e9476db234134c46ddf0e154ca17028]

in testcase: boot

config: i386-randconfig-2006-20250804
compiler: gcc-14
test machine: qemu-system-x86_64 -enable-kvm -cpu SandyBridge -smp 2 -m 32G

(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/202605052050.8156b7e0-lkp@intel.com



[  983.510203][   T24] INFO: task kworker/u4:2:45 blocked for more than 492 seconds.
[  983.696012][   T24]       Not tainted 7.0.0-rc1+ #1
[  983.730478][   T24] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[  983.906134][   T24] task:kworker/u4:2    state:D stack:0     pid:45    tgid:45    ppid:44     task_flags:0x8040 flags:0x00080000
[  984.159850][   T24] Call Trace:
[  984.407777][   T24]  __schedule (sched/core.c:5295 sched/core.c:6908)
[  984.706338][   T24]  ? sched_submit_work (linux/blkdev.h:1205 sched/core.c:6969)
[  984.907449][   T24]  schedule (sched/core.c:6990 sched/core.c:7005)
[  985.006131][   T24]  async_synchronize_cookie_domain (async.c:317 (discriminator 7))
[  985.104747][   T24]  ? swake_up_all (sched/swait.c:82)
[  985.203211][   T24]  wait_for_initramfs (initramfs.c:778)
[  985.307882][   T24]  call_usermodehelper_exec_async (umh.c:108)
[  985.394170][   T24]  ? umh_complete (umh.c:58)
[  985.706723][   T24]  ret_from_fork (x86/kernel/process.c:158)
[  985.779811][   T24]  ? umh_complete (umh.c:58)
[  986.710694][   T24]  ret_from_fork_asm (x86/entry/entry_32.S:736)
[  987.013319][   T24]  entry_INT80_32 (x86/entry/entry_32.S:940)
[  987.306125][   T24]
[  987.306125][   T24] Showing all locks held in the system:
[  987.502551][   T24] 4 locks held by kworker/u4:0/12:
[  987.544601][   T24] 1 lock held by khungtaskd/24:
[  987.693891][   T24]  #0: b22ae69c (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire (linux/rcupdate.h:311)
[  987.857208][   T24] 2 locks held by kworker/u4:2/44:
[  988.011251][   T24]  #0: b30d6cc0 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_one_work (workqueue.c:3249)
[  988.109740][   T24]  #1: b39c5f18 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_one_work (workqueue.c:3250)
[  988.412819][   T24]
[  988.545186][   T24] =============================================
[  988.545186][   T24]
BUG: kernel hang in boot stage



The kernel config and materials to reproduce are available at:
https://download.01.org/0day-ci/archive/20260505/202605052050.8156b7e0-lkp@intel.com



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

Re: [linus:master] [sched/fair] 4823725d9d: INFO:task_blocked_for_more_than#seconds

[Peter Zijlstra]

On Tue, May 05, 2026 at 09:19:49PM +0800, kernel test robot wrote:
> 
> 
> Hello,
> 
> 
> for this change "sched/fair: Increase weight bits for avg_vruntime", we reported
> "[peterz-queue:sched/hrtick] [sched/fair]  fb047eb995: Oops:general_protection_fault,probably_for_non-canonical_address#:#[##]KASAN_PTI"
> in [1]
> 
> but we cannot reproduce the issue in [1] now with same tests and the same
> x86_64-randconfig as the kbuild input config for 4823725d9d.
> 
> however, with another i386-randconfig in boot tests, we found some random
> issues for this change which are clean on parent.

Much of that branch has since made its way upstream -- with various bugs
fixed. Can any of this be reproduced on tip/sched/urgent ?