lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [thread-next>] [day] [month] [year] [list]
Message-ID: <202509191647.c48ab569-lkp@intel.com>
Date: Fri, 19 Sep 2025 21:24:32 +0800
From: kernel test robot <oliver.sang@...el.com>
To: Peter Zijlstra <peterz@...radead.org>
CC: <oe-lkp@...ts.linux.dev>, <lkp@...el.com>, <linux-kernel@...r.kernel.org>,
	<sched-ext@...ts.linux.dev>, <aubrey.li@...ux.intel.com>,
	<yu.c.chen@...el.com>, <oliver.sang@...el.com>
Subject: [peterz-queue:sched/cleanup] [sched]  b55442cb4e:
 WARNING:possible_circular_locking_dependency_detected



Hello,

kernel test robot noticed "WARNING:possible_circular_locking_dependency_detected" on:

commit: b55442cb4ec1669a2034af5d0e65ff30046410f8 ("sched: Employ sched_change guards")
https://git.kernel.org/cgit/linux/kernel/git/peterz/queue.git sched/cleanup

in testcase: trinity
version: trinity-x86_64-ba2360ed-1_20241228
with following parameters:

	runtime: 300s
	group: group-01
	nr_groups: 5


config: x86_64-randconfig-007-20250917
compiler: clang-20
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@...el.com>
| Closes: https://lore.kernel.org/oe-lkp/202509191647.c48ab569-lkp@intel.com


since we don't have enable knowledge about the relation between this commit
and the issues we observed, we just try to run more times. parent keeps clean
while this commit shows various issues.

=========================================================================================
tbox_group/testcase/rootfs/kconfig/compiler/runtime/group/nr_groups:
  vm-snb/trinity/debian-12-x86_64-20240206.cgz/x86_64-randconfig-007-20250917/clang-20/300s/group-01/5

5b726e9bf9544a34 b55442cb4ec1669a2034af5d0e6
---------------- ---------------------------
       fail:runs  %reproduction    fail:runs
           |             |             |
           :200         28%          55:198   dmesg.BUG:kernel_failed_in_early-boot_stage,last_printk:Booting_the_kernel(entry_offset:#)
           :200          5%          10:198   dmesg.BUG:kernel_hang_in_test_stage
           :200          0%           1:198   dmesg.BUG:soft_lockup-CPU##stuck_for#s![(udev-worker):#]
           :200          0%           1:198   dmesg.BUG:soft_lockup-CPU##stuck_for#s![sed:#]
           :200          0%           1:198   dmesg.BUG:soft_lockup-CPU##stuck_for#s![trinity##]
           :200          3%           6:198   dmesg.KASAN:null-ptr-deref_in_range[#-#]
           :200          3%           6:198   dmesg.Kernel_panic-not_syncing:Fatal_exception
           :200          2%           3:198   dmesg.Kernel_panic-not_syncing:softlockup:hung_tasks
           :200          3%           6:198   dmesg.Oops:general_protection_fault,probably_for_non-canonical_address#:#[##]SMP_KASAN
           :200          2%           4:198   dmesg.RIP:__rb_erase_color
           :200          9%          18:198   dmesg.RIP:pick_next_task_fair
           :200          1%           2:198   dmesg.RIP:pick_task_fair
           :200          0%           1:198   dmesg.RIP:place_entity
           :200         10%          19:198   dmesg.RIP:put_prev_task_fair
           :200         10%          19:198   dmesg.RIP:sched_change_begin
           :200          2%           3:198   dmesg.RIP:smp_call_function_many_cond
           :200          9%          18:198   dmesg.WARNING:at_kernel/sched/fair.c:#pick_next_task_fair
           :200          0%           1:198   dmesg.WARNING:at_kernel/sched/fair.c:#place_entity
           :200         10%          19:198   dmesg.WARNING:at_kernel/sched/fair.c:#put_prev_task_fair
           :200         10%          19:198   dmesg.WARNING:at_kernel/sched/sched.h:#sched_change_begin
           :200         10%          19:198   dmesg.WARNING:possible_circular_locking_dependency_detected



[   37.369088][  T318] ------------[ cut here ]------------
[   37.369228][  T318]
[   37.369230][  T318] ======================================================
[   37.369231][  T318] WARNING: possible circular locking dependency detected
[   37.369233][  T318] 6.17.0-rc4-00010-gb55442cb4ec1 #1 Not tainted
[   37.369235][  T318] ------------------------------------------------------
[   37.369236][  T318] v4l_id/318 is trying to acquire lock:
[ 37.369237][ T318] ffffffff85719f40 (console_owner){-.-.}-{0:0}, at: console_flush_all (include/linux/rcupdate.h:336 include/linux/srcu.h:319 kernel/printk/printk.c:288 kernel/printk/printk.c:3203) 
[   37.369249][  T318]
[   37.369249][  T318] but task is already holding lock:
[ 37.369250][ T318] ffff8883aeff5298 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested (kernel/sched/core.c:?) 
[   37.369255][  T318]
[   37.369255][  T318] which lock already depends on the new lock.
[   37.369255][  T318]
[   37.369256][  T318]
[   37.369256][  T318] the existing dependency chain (in reverse order) is:
[   37.369257][  T318]
[   37.369257][  T318] -> #4 (&rq->__lock){-.-.}-{2:2}:
[ 37.369260][ T318] _raw_spin_lock_nested (kernel/locking/spinlock.c:378) 
[ 37.369263][ T318] raw_spin_rq_lock_nested (kernel/sched/core.c:?) 
[ 37.369265][ T318] __task_rq_lock (include/linux/sched.h:2226) 
[ 37.369267][ T318] wake_up_new_task (kernel/sched/core.c:4867) 
[ 37.369269][ T318] kernel_clone (kernel/fork.c:2639) 
[ 37.369272][ T318] user_mode_thread (kernel/fork.c:2683) 
[ 37.369274][ T318] rest_init (init/main.c:709) 
[ 37.369276][ T318] start_kernel (init/main.c:1038) 
[ 37.369279][ T318] x86_64_start_reservations (??:?) 
[ 37.369282][ T318] x86_64_start_kernel (arch/x86/kernel/head64.c:231) 
[ 37.369284][ T318] common_startup_64 (arch/x86/kernel/head_64.S:419) 
[   37.369285][  T318]
[   37.369285][  T318] -> #3 (&p->pi_lock){-.-.}-{2:2}:
[ 37.369288][ T318] _raw_spin_lock_irqsave (include/linux/spinlock_api_smp.h:110 kernel/locking/spinlock.c:162) 
[ 37.369290][ T318] try_to_wake_up (include/linux/spinlock.h:? kernel/sched/core.c:4216) 
[ 37.369292][ T318] __wake_up_common_lock (kernel/sched/wait.c:109) 
[ 37.369295][ T318] tty_port_default_wakeup (drivers/tty/tty_port.c:70) 
[ 37.369298][ T318] serial8250_tx_chars (drivers/tty/serial/8250/8250_port.c:1735) 
[ 37.369300][ T318] serial8250_handle_irq (include/linux/serial_core.h:1231) 
[ 37.369301][ T318] serial8250_interrupt (drivers/tty/serial/8250/8250_core.c:82) 
[ 37.369305][ T318] __handle_irq_event_percpu (kernel/irq/handle.c:?) 
[ 37.369306][ T318] handle_irq_event (kernel/irq/handle.c:?) 
[ 37.369308][ T318] handle_edge_irq (kernel/irq/chip.c:857) 
[ 37.369310][ T318] __common_interrupt (include/asm-generic/irq_regs.h:28 arch/x86/kernel/irq.c:328) 
[ 37.369312][ T318] common_interrupt (arch/x86/kernel/irq.c:318) 
[ 37.369315][ T318] asm_common_interrupt (arch/x86/include/asm/idtentry.h:693) 
[ 37.369317][ T318] _raw_spin_unlock_irqrestore (include/linux/spinlock_api_smp.h:152) 
[ 37.369319][ T318] stack_depot_save_flags (lib/stackdepot.c:722) 
[ 37.369322][ T318] kasan_save_track (arch/x86/include/asm/current.h:25 mm/kasan/common.c:60 mm/kasan/common.c:69) 
[ 37.369324][ T318] __kasan_slab_alloc (mm/kasan/common.c:359) 
[ 37.369326][ T318] kmem_cache_alloc_noprof (include/linux/kasan.h:250 mm/slub.c:4180 mm/slub.c:4229 mm/slub.c:4236) 
[ 37.369329][ T318] fill_pool (lib/debugobjects.c:372) 
[ 37.369331][ T318] debug_object_assert_init (lib/debugobjects.c:726) 
[ 37.369332][ T318] __try_to_del_timer_sync (kernel/time/timer.c:? kernel/time/timer.c:848 kernel/time/timer.c:1457) 
[ 37.369336][ T318] __timer_delete_sync (kernel/time/timer.c:1622) 
[ 37.369337][ T318] schedule_timeout (kernel/time/sleep_timeout.c:103) 
[ 37.369339][ T318] rcu_gp_fqs_loop (kernel/rcu/tree.c:2083) 
[ 37.369341][ T318] rcu_gp_kthread (kernel/rcu/tree.c:2288) 
[ 37.369342][ T318] kthread (kernel/kthread.c:465) 
[ 37.369344][ T318] ret_from_fork (arch/x86/kernel/process.c:154) 
[ 37.369346][ T318] ret_from_fork_asm (arch/x86/entry/entry_64.S:258) 
[   37.369350][  T318]
[   37.369350][  T318] -> #2 (&tty->write_wait){-.-.}-{3:3}:
[ 37.369352][ T318] _raw_spin_lock_irqsave (include/linux/spinlock_api_smp.h:110 kernel/locking/spinlock.c:162) 
[ 37.369354][ T318] __wake_up_common_lock (kernel/sched/wait.c:?) 
[ 37.369356][ T318] tty_port_default_wakeup (drivers/tty/tty_port.c:70) 
[ 37.369358][ T318] serial8250_tx_chars (drivers/tty/serial/8250/8250_port.c:1735) 
[ 37.369359][ T318] serial8250_handle_irq (include/linux/serial_core.h:1231) 
[ 37.369360][ T318] serial8250_interrupt (drivers/tty/serial/8250/8250_core.c:82) 
[ 37.369363][ T318] __handle_irq_event_percpu (kernel/irq/handle.c:?) 
[ 37.369364][ T318] handle_irq_event (kernel/irq/handle.c:?) 
[ 37.369365][ T318] handle_edge_irq (kernel/irq/chip.c:857) 
[ 37.369367][ T318] __common_interrupt (include/asm-generic/irq_regs.h:28 arch/x86/kernel/irq.c:328) 
[ 37.369369][ T318] common_interrupt (arch/x86/kernel/irq.c:318) 
[ 37.369371][ T318] asm_common_interrupt (arch/x86/include/asm/idtentry.h:693) 
[ 37.369372][ T318] _raw_spin_unlock_irqrestore (include/linux/spinlock_api_smp.h:152) 
[ 37.369374][ T318] uart_port_unlock_deref (drivers/tty/serial/serial_core.c:74 drivers/tty/serial/serial_core.c:92) 
[ 37.369375][ T318] uart_write (drivers/tty/serial/serial_core.c:639) 
[ 37.369377][ T318] do_output_char (drivers/tty/n_tty.c:?) 
[ 37.369380][ T318] n_tty_write (drivers/tty/n_tty.c:486 drivers/tty/n_tty.c:2388) 
[ 37.369381][ T318] file_tty_write (drivers/tty/tty_io.c:1006) 
[ 37.369382][ T318] do_iter_readv_writev (fs/read_write.c:828) 
[ 37.369385][ T318] vfs_writev (fs/read_write.c:1057) 
[ 37.369387][ T318] do_writev (fs/read_write.c:?) 
[ 37.369389][ T318] do_syscall_64 (arch/x86/entry/syscall_64.c:?) 
[ 37.369391][ T318] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130) 
[   37.369393][  T318]
[   37.369393][  T318] -> #1 (&port_lock_key){-.-.}-{3:3}:
[ 37.369395][ T318] _raw_spin_lock_irqsave (include/linux/spinlock_api_smp.h:110 kernel/locking/spinlock.c:162) 
[ 37.369397][ T318] serial8250_console_write (include/linux/serial_core.h:?) 
[ 37.369399][ T318] console_flush_all (kernel/printk/printk.c:3055 kernel/printk/printk.c:3139 kernel/printk/printk.c:3226) 
[ 37.369400][ T318] console_unlock (kernel/printk/printk.c:3285 kernel/printk/printk.c:3325) 
[ 37.369401][ T318] vprintk_emit (kernel/printk/printk.c:?) 
[ 37.369403][ T318] _printk (kernel/printk/printk.c:2478) 
[ 37.369405][ T318] register_console (kernel/printk/printk.c:4127) 
[ 37.369406][ T318] univ8250_console_init (drivers/tty/serial/8250/8250_core.c:?) 
[ 37.369408][ T318] console_init (kernel/printk/printk.c:4325) 
[ 37.369411][ T318] start_kernel (init/main.c:1036) 
[ 37.369413][ T318] x86_64_start_reservations (??:?) 
[ 37.369415][ T318] x86_64_start_kernel (arch/x86/kernel/head64.c:231) 
[ 37.369417][ T318] common_startup_64 (arch/x86/kernel/head_64.S:419) 
[   37.369418][  T318]
[   37.369418][  T318] -> #0 (console_owner){-.-.}-{0:0}:
[ 37.369420][ T318] __lock_acquire (kernel/locking/lockdep.c:3166) 
[ 37.369422][ T318] lock_acquire (kernel/locking/lockdep.c:5868) 
[ 37.369424][ T318] console_flush_all (kernel/printk/printk.c:1924) 
[ 37.369426][ T318] console_unlock (kernel/printk/printk.c:3285 kernel/printk/printk.c:3325) 
[ 37.369427][ T318] vprintk_emit (kernel/printk/printk.c:?) 
[ 37.369428][ T318] _printk (kernel/printk/printk.c:2478) 
[ 37.369429][ T318] report_bug (lib/bug.c:?) 
[ 37.369431][ T318] handle_bug (arch/x86/kernel/traps.c:338) 
[ 37.369433][ T318] exc_invalid_op (arch/x86/kernel/traps.c:392) 
[ 37.369435][ T318] asm_exc_invalid_op (arch/x86/include/asm/idtentry.h:621) 
[ 37.369437][ T318] sched_change_begin (kernel/sched/sched.h:2447) 
[ 37.369439][ T318] sched_move_task (kernel/sched/sched.h:3873 kernel/sched/core.c:9226) 
[ 37.369440][ T318] do_exit (kernel/exit.c:965) 
[ 37.369442][ T318] do_group_exit (kernel/exit.c:1081) 
[ 37.369444][ T318] __cfi___ia32_sys_exit_group (kernel/exit.c:1113) 
[ 37.369446][ T318] x64_sys_call (??:?) 
[ 37.369447][ T318] do_syscall_64 (arch/x86/entry/syscall_64.c:?) 
[ 37.369449][ T318] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130) 
[   37.369451][  T318]
[   37.369451][  T318] other info that might help us debug this:
[   37.369451][  T318]
[   37.369451][  T318] Chain exists of:
[   37.369451][  T318]   console_owner --> &p->pi_lock --> &rq->__lock
[   37.369451][  T318]
[   37.369455][  T318]  Possible unsafe locking scenario:
[   37.369455][  T318]
[   37.369456][  T318]        CPU0                    CPU1
[   37.369456][  T318]        ----                    ----
[   37.369457][  T318]   lock(&rq->__lock);
[   37.369458][  T318]                                lock(&p->pi_lock);
[   37.369460][  T318]                                lock(&rq->__lock);
[   37.369461][  T318]   lock(console_owner);
[   37.369463][  T318]
[   37.369463][  T318]  *** DEADLOCK ***
[   37.369463][  T318]
[   37.369464][  T318] 4 locks held by v4l_id/318:
[ 37.369465][ T318] #0: ffff8881ab704378 (&p->pi_lock){-.-.}-{2:2}, at: task_rq_lock (kernel/sched/core.c:734) 
[ 37.369470][ T318] #1: ffff8883aeff5298 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested (kernel/sched/core.c:?) 
[ 37.369474][ T318] #2: ffffffff85719fa0 (console_lock){+.+.}-{0:0}, at: _printk (kernel/printk/printk.c:2478) 
[ 37.369478][ T318] #3: ffffffff85329830 (console_srcu){....}-{0:0}, at: console_flush_all (include/linux/rcupdate.h:336 include/linux/srcu.h:319 kernel/printk/printk.c:288 kernel/printk/printk.c:3203) 
[   37.369482][  T318]
[   37.369482][  T318] stack backtrace:
[   37.369484][  T318] CPU: 1 UID: 0 PID: 318 Comm: v4l_id Not tainted 6.17.0-rc4-00010-gb55442cb4ec1 #1 PREEMPT(voluntary)  f9b7745e0f49cb37d78d99070980d0f206cf36b5
[   37.369487][  T318] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
[   37.369490][  T318] Call Trace:
[   37.369492][  T318]  <TASK>
[ 37.369493][ T318] dump_stack_lvl (lib/dump_stack.c:123) 
[ 37.369497][ T318] print_circular_bug (kernel/locking/lockdep.c:2045) 
[ 37.369501][ T318] check_noncircular (kernel/locking/lockdep.c:?) 
[ 37.369505][ T318] __lock_acquire (kernel/locking/lockdep.c:3166) 
[ 37.369512][ T318] lock_acquire (kernel/locking/lockdep.c:5868) 
[ 37.369514][ T318] ? console_flush_all (include/linux/rcupdate.h:336 include/linux/srcu.h:319 kernel/printk/printk.c:288 kernel/printk/printk.c:3203) 
[ 37.369517][ T318] ? do_raw_spin_unlock (arch/x86/include/asm/atomic.h:23) 


The kernel config and materials to reproduce are available at:
https://download.01.org/0day-ci/archive/20250919/202509191647.c48ab569-lkp@intel.com



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


Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ