rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P3696/1:b..l P3644/1:b..l (detected by 0, t=10502 jiffies, g=13301, q=155) task:kworker/u4:5 state:R running task stack:20160 pid: 3644 ppid: 2 flags:0x00004000 Workqueue: bat_events batadv_iv_send_outstanding_bat_ogm_packet Call Trace: context_switch kernel/sched/core.c:5030 [inline] __schedule+0x12c4/0x45b0 kernel/sched/core.c:6376 preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6780 irqentry_exit+0x53/0x80 kernel/entry/common.c:432 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:batadv_iv_ogm_slide_own_bcast_window net/batman-adv/bat_iv_ogm.c:772 [inline] RIP: 0010:batadv_iv_ogm_schedule_buff net/batman-adv/bat_iv_ogm.c:826 [inline] RIP: 0010:batadv_iv_ogm_schedule+0x65b/0x1000 net/batman-adv/bat_iv_ogm.c:869 Code: f7 eb 05 e8 a7 fe 74 f7 e8 52 b0 27 00 89 c3 31 ff 89 c6 e8 f7 01 75 f7 85 db 74 15 e8 5e b5 5f f7 84 c0 74 18 e8 85 fe 74 f7 <4c> 8b 6c 24 30 eb 65 e8 79 fe 74 f7 4c 8b 6c 24 30 eb 59 e8 1d b0 RSP: 0018:ffffc90003b97a60 EFLAGS: 00000293 RAX: ffffffff8a0b62db RBX: 0000000000000001 RCX: ffff88801d440000 RDX: 0000000000000000 RSI: ffffffff8ad8f7e0 RDI: ffffffff8ad8f7a0 RBP: ffffc90003b97b98 R08: ffffffff8a0b62c9 R09: fffffbfff1f8e019 R10: 0000000000000000 R11: dffffc0000000001 R12: ffff888076593000 R13: ffff88802428cc00 R14: ffff888019141e98 R15: dffffc0000000000 batadv_iv_send_outstanding_bat_ogm_packet+0x6fa/0x800 net/batman-adv/bat_iv_ogm.c:1713 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310 worker_thread+0xaca/0x1280 kernel/workqueue.c:2457 kthread+0x3f6/0x4f0 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 task:kworker/u4:7 state:R running task stack:21752 pid: 3696 ppid: 2 flags:0x00004000 Workqueue: writeback wb_workfn (flush-8:0) Call Trace: context_switch kernel/sched/core.c:5030 [inline] __schedule+0x12c4/0x45b0 kernel/sched/core.c:6376 preempt_schedule_notrace+0xf8/0x140 kernel/sched/core.c:6631 preempt_schedule_notrace_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:35 rcu_is_watching+0x72/0xa0 kernel/rcu/tree.c:1124 trace_lock_acquire include/trace/events/lock.h:13 [inline] lock_acquire+0xdd/0x4f0 kernel/locking/lockdep.c:5594 rcu_lock_acquire+0x2a/0x30 include/linux/rcupdate.h:312 rcu_read_lock include/linux/rcupdate.h:739 [inline] percpu_ref_put_many include/linux/percpu-refcount.h:317 [inline] percpu_ref_put include/linux/percpu-refcount.h:338 [inline] blk_mq_sched_insert_requests+0x2dc/0x570 block/blk-mq-sched.c:521 blk_mq_flush_plug_list+0x5de/0x6b0 block/blk-mq.c:1965 blk_flush_plug_list+0x44b/0x490 block/blk-core.c:1734 blk_schedule_flush_plug include/linux/blkdev.h:1235 [inline] io_schedule_prepare kernel/sched/core.c:8452 [inline] io_schedule+0x7f/0x100 kernel/sched/core.c:8483 rq_qos_wait+0x2e8/0x400 block/blk-rq-qos.c:288 __wbt_wait block/blk-wbt.c:522 [inline] wbt_wait+0x3ce/0x6c0 block/blk-wbt.c:586 __rq_qos_throttle+0x61/0xa0 block/blk-rq-qos.c:72 rq_qos_throttle block/blk-rq-qos.h:203 [inline] blk_mq_submit_bio+0x4fa/0x1c40 block/blk-mq.c:2226 __submit_bio+0x813/0x850 block/blk-core.c:917 __submit_bio_noacct_mq block/blk-core.c:997 [inline] submit_bio_noacct+0x955/0xb30 block/blk-core.c:1027 submit_bio+0x2dd/0x560 block/blk-core.c:1089 ext4_io_submit fs/ext4/page-io.c:381 [inline] io_submit_add_bh fs/ext4/page-io.c:425 [inline] ext4_bio_write_page+0x1365/0x1cc0 fs/ext4/page-io.c:553 mpage_submit_page+0x18d/0x230 fs/ext4/inode.c:2101 mpage_process_page_bufs+0x6c8/0x8b0 fs/ext4/inode.c:2215 mpage_prepare_extent_to_map+0xc9d/0x1150 fs/ext4/inode.c:2643 ext4_writepages+0xcd0/0x3d10 fs/ext4/inode.c:2771 do_writepages+0x481/0x730 mm/page-writeback.c:2386 __writeback_single_inode+0x15b/0xe30 fs/fs-writeback.c:1647 writeback_sb_inodes+0xbce/0x1a40 fs/fs-writeback.c:1930 __writeback_inodes_wb+0x114/0x400 fs/fs-writeback.c:2001 wb_writeback+0x465/0xc50 fs/fs-writeback.c:2106 wb_check_old_data_flush fs/fs-writeback.c:2206 [inline] wb_do_writeback fs/fs-writeback.c:2259 [inline] wb_workfn+0xc55/0x1130 fs/fs-writeback.c:2288 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310 worker_thread+0xaca/0x1280 kernel/workqueue.c:2457 kthread+0x3f6/0x4f0 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 rcu: rcu_preempt kthread timer wakeup didn't happen for 10421 jiffies! g13301 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=1 timer-softirq=6416 rcu: rcu_preempt kthread starved for 10422 jiffies! g13301 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:26816 pid: 15 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5030 [inline] __schedule+0x12c4/0x45b0 kernel/sched/core.c:6376 schedule+0x11b/0x1f0 kernel/sched/core.c:6459 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1914 rcu_gp_fqs_loop+0x2bf/0x1080 kernel/rcu/tree.c:1972 rcu_gp_kthread+0xa4/0x360 kernel/rcu/tree.c:2145 kthread+0x3f6/0x4f0 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 rcu: Stack dump where RCU GP kthread last ran: Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline] NMI backtrace for cpu 1 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline] NMI backtrace for cpu 1 skipped: idling at acpi_safe_halt drivers/acpi/processor_idle.c:108 [inline] NMI backtrace for cpu 1 skipped: idling at acpi_idle_do_entry+0x10f/0x340 drivers/acpi/processor_idle.c:562 sched: RT throttling activated vkms_vblank_simulate: vblank timer overrun