rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: (detected by 1, t=10502 jiffies, g=308053, q=45) rcu: All QSes seen, last rcu_preempt kthread activity 10498 (4295095172-4295084674), jiffies_till_next_fqs=1, root ->qsmask 0x0 syz-executor.4 R running task 27336 29976 8143 0x00000008 Call Trace: sched_show_task.cold+0x332/0x396 kernel/sched/core.c:5341 print_other_cpu_stall kernel/rcu/tree.c:1430 [inline] check_cpu_stall kernel/rcu/tree.c:1557 [inline] __rcu_pending kernel/rcu/tree.c:3293 [inline] rcu_pending kernel/rcu/tree.c:3336 [inline] rcu_check_callbacks.cold+0xb37/0xe19 kernel/rcu/tree.c:2682 update_process_times+0x2a/0xb0 kernel/time/timer.c:1650 tick_sched_handle+0x9b/0x180 kernel/time/tick-sched.c:168 tick_sched_timer+0xfc/0x290 kernel/time/tick-sched.c:1278 __run_hrtimer kernel/time/hrtimer.c:1401 [inline] __hrtimer_run_queues+0x3f6/0xe60 kernel/time/hrtimer.c:1463 hrtimer_interrupt+0x32a/0x930 kernel/time/hrtimer.c:1521 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1067 [inline] smp_apic_timer_interrupt+0x10c/0x550 arch/x86/kernel/apic/apic.c:1092 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:894 RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:169 [inline] RIP: 0010:_raw_spin_unlock_irq+0x50/0x80 kernel/locking/spinlock.c:192 Code: c0 58 7f f1 89 48 ba 00 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 75 31 48 83 3d 61 40 dc 01 00 74 25 fb 66 0f 1f 44 00 00 01 00 00 00 e8 36 69 2d f9 65 8b 05 ff 9f ec 77 85 c0 74 02 5d RSP: 0018:ffff8880ba107dd0 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff13 RAX: 1ffffffff13e2feb RBX: dffffc0000000000 RCX: 1ffff11005af3d35 RDX: dffffc0000000000 RSI: ffff88802d79e988 RDI: ffff88802d79e984 RBP: ffff8880ba122b00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff86a63fc0 R13: ffff8880ba122b00 R14: ffff8880ba107e68 R15: 0000000000000000 expire_timers+0x238/0x4e0 kernel/time/timer.c:1374 __run_timers kernel/time/timer.c:1703 [inline] run_timer_softirq+0x21c/0x670 kernel/time/timer.c:1716 __do_softirq+0x26c/0x9a0 kernel/softirq.c:292 invoke_softirq kernel/softirq.c:372 [inline] irq_exit+0x215/0x260 kernel/softirq.c:412 exiting_irq arch/x86/include/asm/apic.h:544 [inline] smp_apic_timer_interrupt+0x136/0x550 arch/x86/kernel/apic/apic.c:1094 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:894 RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:789 [inline] RIP: 0010:lock_release+0x429/0x8b0 kernel/locking/lockdep.c:3929 Code: 84 08 00 00 00 00 00 00 48 c1 e8 03 80 3c 10 00 0f 85 95 03 00 00 48 83 3d 5b ea a4 08 00 0f 84 cc 01 00 00 48 8b 3c 24 57 9d <0f> 1f 44 00 00 48 b8 00 00 00 00 00 fc ff df 49 c7 04 04 00 00 00 RSP: 0018:ffff888015847820 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff13 RAX: 1ffffffff13e2fe9 RBX: ffff88802d79e100 RCX: 1ffff11005af3d36 RDX: dffffc0000000000 RSI: 0000000000000002 RDI: 0000000000000282 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000001 R10: 0000000000000000 R11: 00000000c255c392 R12: 1ffff11002b08f07 R13: bb91fc1950bbb840 R14: ffff88802d79e100 R15: 0000000000000002 __mutex_unlock_slowpath+0x89/0x610 kernel/locking/mutex.c:1197 kernfs_add_one+0x2d0/0x4c0 fs/kernfs/dir.c:801 __kernfs_create_file+0x293/0x33f fs/kernfs/file.c:1021 sysfs_add_file_mode_ns+0x226/0x540 fs/sysfs/file.c:306 create_files fs/sysfs/group.c:63 [inline] internal_create_group+0x355/0xb20 fs/sysfs/group.c:147 loop_sysfs_init drivers/block/loop.c:851 [inline] loop_set_fd drivers/block/loop.c:1003 [inline] lo_ioctl+0xf7c/0x20e0 drivers/block/loop.c:1576 __blkdev_driver_ioctl block/ioctl.c:303 [inline] blkdev_ioctl+0x5cb/0x1a7e block/ioctl.c:601 block_ioctl+0xe9/0x130 fs/block_dev.c:1906 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:501 [inline] do_vfs_ioctl+0xcdb/0x12e0 fs/ioctl.c:688 ksys_ioctl+0x9b/0xc0 fs/ioctl.c:705 __do_sys_ioctl fs/ioctl.c:712 [inline] __se_sys_ioctl fs/ioctl.c:710 [inline] __x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:710 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45dcc7 Code: 48 83 c4 08 48 89 d8 5b 5d c3 66 0f 1f 84 00 00 00 00 00 48 89 e8 48 f7 d8 48 39 c3 0f 92 c0 eb 92 66 90 b8 10 00 00 00 0f 05 <48> 3d 01 f0 ff ff 0f 83 6d b5 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f043e76fa28 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 000000000045dcc7 RDX: 0000000000000004 RSI: 0000000000004c00 RDI: 0000000000000005 RBP: 0000000000000000 R08: 00000000200002f0 R09: 0000000000000000 R10: 0000000000011180 R11: 0000000000000246 R12: 000000000000000a R13: 0000000000000004 R14: 0000000000000004 R15: 0000000020000300 rcu: rcu_preempt kthread starved for 10498 jiffies! g308053 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1 rcu: RCU grace-period kthread stack dump: rcu_preempt R running task 29208 10 2 0x80000000 Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0x887/0x2040 kernel/sched/core.c:3517 schedule+0x8d/0x1b0 kernel/sched/core.c:3561 schedule_timeout+0x4cf/0xfe0 kernel/time/timer.c:1825 rcu_gp_kthread+0xdad/0x21c0 kernel/rcu/tree.c:2202 kthread+0x33f/0x460 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 nla_parse: 13 callbacks suppressed netlink: 12 bytes leftover after parsing attributes in process `syz-executor.1'. IPVS: ftp: loaded support on port[0] = 21 chnl_net:caif_netlink_parms(): no params data found bridge0: port 1(bridge_slave_0) entered blocking state bridge0: port 1(bridge_slave_0) entered disabled state device bridge_slave_0 entered promiscuous mode bridge0: port 2(bridge_slave_1) entered blocking state bridge0: port 2(bridge_slave_1) entered disabled state device bridge_slave_1 entered promiscuous mode