rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P4103/1:b..l P3640/1:b..l (detected by 1, t=10502 jiffies, g=4589, q=18) task:udevd state:R running task stack: 0 pid: 3640 ppid: 1 flags:0x00000004 Call trace: __switch_to+0x308/0x5e8 arch/arm64/kernel/process.c:518 context_switch kernel/sched/core.c:5027 [inline] __schedule+0xf10/0x1e48 kernel/sched/core.c:6373 preempt_schedule_irq+0x90/0x274 kernel/sched/core.c:6777 arm64_preempt_schedule_irq+0x174/0x2c4 arch/arm64/kernel/entry-common.c:260 el1_interrupt+0x40/0x58 arch/arm64/kernel/entry-common.c:463 el1h_64_irq_handler+0x18/0x24 arch/arm64/kernel/entry-common.c:470 el1h_64_irq+0x78/0x7c arch/arm64/kernel/entry.S:522 arch_local_irq_restore arch/arm64/include/asm/irqflags.h:122 [inline] seqcount_lockdep_reader_access+0x228/0x2d0 include/linux/seqlock.h:105 read_seqbegin include/linux/seqlock.h:840 [inline] read_seqbegin_or_lock include/linux/seqlock.h:1144 [inline] prepend_path+0xd8/0xaf8 fs/d_path.c:167 d_absolute_path+0x13c/0x27c fs/d_path.c:235 tomoyo_get_absolute_path security/tomoyo/realpath.c:101 [inline] tomoyo_realpath_from_path+0x2a4/0x508 security/tomoyo/realpath.c:276 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_path_perm+0x208/0x568 security/tomoyo/file.c:822 tomoyo_inode_getattr+0x28/0x38 security/tomoyo/tomoyo.c:122 security_inode_getattr+0xd8/0x124 security/security.c:1348 vfs_getattr fs/stat.c:157 [inline] vfs_statx+0x16c/0x378 fs/stat.c:225 vfs_fstatat fs/stat.c:243 [inline] __do_sys_newfstatat fs/stat.c:411 [inline] __se_sys_newfstatat fs/stat.c:405 [inline] __arm64_sys_newfstatat+0x110/0x194 fs/stat.c:405 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181 el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584 task:syz.0.1 state:R running task stack: 0 pid: 4103 ppid: 4029 flags:0x00000000 Call trace: __switch_to+0x308/0x5e8 arch/arm64/kernel/process.c:518 context_switch kernel/sched/core.c:5027 [inline] __schedule+0xf10/0x1e48 kernel/sched/core.c:6373 preempt_schedule_common+0x140/0x260 kernel/sched/core.c:6549 preempt_schedule+0x64/0x84 kernel/sched/core.c:6574 __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:169 [inline] _raw_spin_unlock_irq+0xf0/0x134 kernel/locking/spinlock.c:202 spin_unlock_irq include/linux/spinlock.h:413 [inline] loop_queue_work drivers/block/loop.c:1068 [inline] loop_queue_rq+0x9b0/0xb20 drivers/block/loop.c:2201 __blk_mq_issue_directly block/blk-mq.c:2008 [inline] __blk_mq_try_issue_directly+0x40c/0x6a0 block/blk-mq.c:2064 blk_mq_try_issue_directly+0x108/0x334 block/blk-mq.c:2095 blk_mq_submit_bio+0xf40/0x1ae0 __submit_bio+0x628/0x664 block/blk-core.c:917 __submit_bio_noacct_mq block/blk-core.c:997 [inline] submit_bio_noacct+0x680/0x7dc block/blk-core.c:1027 submit_bio+0x394/0x68c block/blk-core.c:1089 submit_bh_wbc+0x4c0/0x610 fs/buffer.c:3056 submit_bh fs/buffer.c:3062 [inline] __bread_slow fs/buffer.c:1180 [inline] __bread_gfp+0xf4/0x33c fs/buffer.c:1384 sb_bread_unmovable include/linux/buffer_head.h:343 [inline] ntfs_bread fs/ntfs3/fsntfs.c:999 [inline] ntfs_read_run_nb+0x3fc/0xccc fs/ntfs3/fsntfs.c:1219 ntfs_read_bh+0x58/0x29c fs/ntfs3/fsntfs.c:1287 mi_read+0x170/0x4d8 fs/ntfs3/record.c:133 mi_format_new+0x174/0x514 fs/ntfs3/record.c:374 ni_add_subrecord+0xd0/0x3c4 fs/ntfs3/frecord.c:370 ntfs_look_free_mft+0x4c8/0xd0c fs/ntfs3/fsntfs.c:686 ni_ins_attr_ext+0x2e0/0x99c fs/ntfs3/frecord.c:1011 ni_insert_attr+0x354/0x7b4 fs/ntfs3/frecord.c:1103 ni_insert_resident+0x100/0x384 fs/ntfs3/frecord.c:1477 ntfs_set_ea+0x9ec/0x1228 fs/ntfs3/xattr.c:444 ntfs_setxattr+0x178/0x720 fs/ntfs3/xattr.c:952 __vfs_setxattr+0x388/0x3a4 fs/xattr.c:182 __vfs_setxattr_noperm+0x110/0x528 fs/xattr.c:216 __vfs_setxattr_locked+0x1ec/0x218 fs/xattr.c:277 vfs_setxattr+0x1a8/0x344 fs/xattr.c:303 do_setxattr fs/xattr.c:588 [inline] setxattr+0x250/0x2b4 fs/xattr.c:611 path_setxattr+0x17c/0x258 fs/xattr.c:630 __do_sys_setxattr fs/xattr.c:646 [inline] __se_sys_setxattr fs/xattr.c:642 [inline] __arm64_sys_setxattr+0xbc/0xd8 fs/xattr.c:642 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181 el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584 rcu: rcu_preempt kthread starved for 10511 jiffies! g4589 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1 rcu: Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior. rcu: RCU grace-period kthread stack dump: task:rcu_preempt state:R running task stack: 0 pid: 15 ppid: 2 flags:0x00000008 Call trace: __switch_to+0x308/0x5e8 arch/arm64/kernel/process.c:518 context_switch kernel/sched/core.c:5027 [inline] __schedule+0xf10/0x1e48 kernel/sched/core.c:6373 preempt_schedule_common+0x140/0x260 kernel/sched/core.c:6549 preempt_schedule+0x64/0x84 kernel/sched/core.c:6574 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:161 [inline] _raw_spin_unlock_irqrestore+0x114/0x158 kernel/locking/spinlock.c:194 finish_swait+0x170/0x1ac kernel/sched/swait.c:142 rcu_gp_fqs_loop+0x28c/0x13d4 kernel/rcu/tree.c:1972 rcu_gp_kthread+0xc4/0x2c4 kernel/rcu/tree.c:2145 kthread+0x37c/0x45c kernel/kthread.c:334 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:870 rcu: Stack dump where RCU GP kthread last ran: Task dump for CPU 1: task:syz.2.7 state:R running task stack: 0 pid: 4114 ppid: 4027 flags:0x00000001 Call trace: dump_backtrace+0x0/0x530 arch/arm64/kernel/stacktrace.c:152 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:216 sched_show_task+0x43c/0x574 kernel/sched/core.c:8637 dump_cpu_task+0x84/0xa8 kernel/sched/core.c:10924 rcu_check_gp_kthread_starvation+0x1f0/0x254 kernel/rcu/tree_stall.h:488 print_other_cpu_stall+0x202c/0x2290 kernel/rcu/tree_stall.h:592 check_cpu_stall kernel/rcu/tree_stall.h:745 [inline] rcu_pending kernel/rcu/tree.c:3932 [inline] rcu_sched_clock_irq+0x1894/0x1b8c kernel/rcu/tree.c:2619 update_process_times+0x1d4/0x270 kernel/time/timer.c:1818 tick_sched_handle kernel/time/tick-sched.c:254 [inline] tick_sched_timer+0x340/0x4f8 kernel/time/tick-sched.c:1473 __run_hrtimer kernel/time/hrtimer.c:1686 [inline] __hrtimer_run_queues+0x458/0xca4 kernel/time/hrtimer.c:1750 hrtimer_interrupt+0x2c0/0xb64 kernel/time/hrtimer.c:1812 timer_handler drivers/clocksource/arm_arch_timer.c:659 [inline] arch_timer_handler_virt+0x74/0x88 drivers/clocksource/arm_arch_timer.c:670 handle_percpu_devid_irq+0x29c/0x7fc kernel/irq/chip.c:930 generic_handle_irq_desc include/linux/irqdesc.h:158 [inline] handle_irq_desc kernel/irq/irqdesc.c:652 [inline] handle_domain_irq+0xec/0x178 kernel/irq/irqdesc.c:707 gic_handle_irq+0x78/0x1c8 drivers/irqchip/irq-gic-v3.c:758 call_on_irq_stack+0x24/0x4c arch/arm64/kernel/entry.S:899 do_interrupt_handler+0x74/0x94 arch/arm64/kernel/entry-common.c:267 el1_interrupt+0x30/0x58 arch/arm64/kernel/entry-common.c:454 el1h_64_irq_handler+0x18/0x24 arch/arm64/kernel/entry-common.c:470 el1h_64_irq+0x78/0x7c arch/arm64/kernel/entry.S:522 arch_local_irq_enable arch/arm64/include/asm/irqflags.h:35 [inline] __local_bh_enable_ip+0x238/0x470 kernel/softirq.c:388 local_bh_enable+0x28/0x34 include/linux/bottom_half.h:32 put_cpu_fpsimd_context arch/arm64/kernel/fpsimd.c:206 [inline] fpsimd_preserve_current_state+0xd0/0x1c0 arch/arm64/kernel/fpsimd.c:1095 fpsimd_signal_preserve_current_state+0x30/0x1b8 arch/arm64/kernel/fpsimd.c:1105 setup_rt_frame arch/arm64/kernel/signal.c:778 [inline] handle_signal arch/arm64/kernel/signal.c:830 [inline] do_signal arch/arm64/kernel/signal.c:905 [inline] do_notify_resume+0x740/0x32b8 arch/arm64/kernel/signal.c:943 prepare_exit_to_user_mode arch/arm64/kernel/entry-common.c:133 [inline] exit_to_user_mode arch/arm64/kernel/entry-common.c:138 [inline] el0_svc+0xfc/0x1f0 arch/arm64/kernel/entry-common.c:609 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584