rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P9640/1:b..l P5208/1:b..l rcu: (detected by 1, t=10502 jiffies, g=23737, q=353 ncpus=2) task:udevd state:R running task stack:21664 pid:5208 tgid:5208 ppid:1 flags:0x00000002 Call Trace: context_switch kernel/sched/core.c:5328 [inline] __schedule+0x184f/0x4c30 kernel/sched/core.c:6693 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:7015 irqentry_exit+0x5e/0x90 kernel/entry/common.c:354 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:mnt_idmap include/linux/mount.h:79 [inline] RIP: 0010:link_path_walk+0x1a0/0xea0 fs/namei.c:2365 Code: 8b 84 24 90 00 00 00 42 80 3c 20 00 74 08 48 89 ef e8 04 36 e9 ff 48 8b 5d 00 48 83 c3 18 48 89 d8 48 c1 e8 03 42 80 3c 20 00 <74> 08 48 89 df e8 e6 35 e9 ff 48 8b 03 48 89 44 24 78 48 8b 44 24 RSP: 0018:ffffc90004037ac0 EFLAGS: 00000246 RAX: 1ffff11003bd958f RBX: ffff88801decac78 RCX: ffff888044978000 RDX: 0000000000000002 RSI: ffffffff8ea7d210 RDI: 0000000000000072 RBP: ffffc90004037c60 R08: 0000000000000001 R09: ffffffff82158f96 R10: 0000000000000002 R11: ffff888044978000 R12: dffffc0000000000 R13: ffff88802f8fe621 R14: ffffc90004037c68 R15: ffffc90004037c98 path_lookupat+0xa9/0x450 fs/namei.c:2579 filename_lookup+0x256/0x610 fs/namei.c:2609 do_readlinkat+0xf0/0x3a0 fs/stat.c:537 __do_sys_readlink fs/stat.c:574 [inline] __se_sys_readlink fs/stat.c:571 [inline] __x64_sys_readlink+0x7f/0x90 fs/stat.c:571 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f985e917d47 RSP: 002b:00007ffea1b65cc8 EFLAGS: 00000202 ORIG_RAX: 0000000000000059 RAX: ffffffffffffffda RBX: 00007ffea1b664e8 RCX: 00007f985e917d47 RDX: 0000000000000200 RSI: 00007ffea1b65cd8 RDI: 00007ffea1b65ed8 RBP: 000055d600c46910 R08: 0000000000000000 R09: 00007ffea1b65648 R10: 00007f985ee850b8 R11: 0000000000000202 R12: 00007ffea1b65cd8 R13: 00007ffea1b65ed8 R14: 0000000000000000 R15: 0000000000000000 task:syz.1.1492 state:R running task stack:25920 pid:9640 tgid:9640 ppid:5839 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5328 [inline] __schedule+0x184f/0x4c30 kernel/sched/core.c:6693 preempt_schedule_common+0x84/0xd0 kernel/sched/core.c:6872 preempt_schedule+0xe1/0xf0 kernel/sched/core.c:6896 preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk.S:12 __raw_spin_unlock include/linux/spinlock_api_smp.h:143 [inline] _raw_spin_unlock+0x3e/0x50 kernel/locking/spinlock.c:186 spin_unlock include/linux/spinlock.h:391 [inline] zap_pte_range mm/memory.c:1691 [inline] zap_pmd_range mm/memory.c:1739 [inline] zap_pud_range mm/memory.c:1768 [inline] zap_p4d_range mm/memory.c:1789 [inline] unmap_page_range+0x36b1/0x40e0 mm/memory.c:1810 unmap_vmas+0x3cc/0x5f0 mm/memory.c:1900 exit_mmap+0x275/0xc40 mm/mmap.c:1923 __mmput+0x115/0x390 kernel/fork.c:1348 exit_mm+0x220/0x310 kernel/exit.c:571 do_exit+0x9b2/0x28e0 kernel/exit.c:926 do_group_exit+0x207/0x2c0 kernel/exit.c:1088 __do_sys_exit_group kernel/exit.c:1099 [inline] __se_sys_exit_group kernel/exit.c:1097 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1097 x64_sys_call+0x2634/0x2640 arch/x86/include/generated/asm/syscalls_64.h:232 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fca0257e719 RSP: 002b:00007fff3e7f2868 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fca0257e719 RDX: 0000000000000064 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007fff3e7f28bc R08: 00007fff3e7f294f R09: 000000000003774f R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000000032 R13: 000000000003774f R14: 00000000000376ce R15: 00007fff3e7f2910 rcu: rcu_preempt kthread starved for 10568 jiffies! g23737 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0 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:25232 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5328 [inline] __schedule+0x184f/0x4c30 kernel/sched/core.c:6693 __schedule_loop kernel/sched/core.c:6770 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6785 schedule_timeout+0x1be/0x310 kernel/time/timer.c:2615 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2045 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2247 kthread+0x2f2/0x390 kernel/kthread.c:389 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 rcu: Stack dump where RCU GP kthread last ran: Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 5909 Comm: kworker/0:8 Not tainted 6.12.0-rc7-syzkaller-00125-gcfaaa7d010d1 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024 Workqueue: events_power_efficient neigh_periodic_work RIP: 0010:usb_hcd_submit_urb+0x370/0x1e80 Code: 03 42 80 3c 20 00 4c 8b 34 24 74 08 48 89 df e8 86 4a c6 fa 4c 8b 1b 4c 89 f7 48 8b 74 24 08 8b 54 24 20 e8 22 50 99 04 89 c3 <45> 31 f6 31 ff 89 c6 e8 44 72 5c fa 85 db 0f 85 d9 0f 00 00 e8 f7 RSP: 0018:ffffc90000007580 EFLAGS: 00000086 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000102 RDX: 0000000000000000 RSI: 0000000000000004 RDI: 0000000000000001 RBP: ffffc900000076f0 R08: ffff888145718003 R09: 1ffff11028ae3000 R10: dffffc0000000000 R11: ffffed1028ae3001 R12: dffffc0000000000 R13: 1ffff11028b61043 R14: ffff888145b08000 R15: ffff888145b08218 FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000110c24f4fd CR3: 0000000031b4e000 CR4: 0000000000350ef0 Call Trace: ath9k_hif_usb_rx_cb+0x11f7/0x1590 drivers/net/wireless/ath/ath9k/hif_usb.c:722 __usb_hcd_giveback_urb+0x42e/0x6e0 drivers/usb/core/hcd.c:1650 dummy_timer+0x856/0x4620 drivers/usb/gadget/udc/dummy_hcd.c:1993 __run_hrtimer kernel/time/hrtimer.c:1691 [inline] __hrtimer_run_queues+0x59d/0xd50 kernel/time/hrtimer.c:1755 hrtimer_run_softirq+0x19a/0x2c0 kernel/time/hrtimer.c:1772 handle_softirqs+0x2c7/0x980 kernel/softirq.c:554 __do_softirq kernel/softirq.c:588 [inline] invoke_softirq kernel/softirq.c:428 [inline] __irq_exit_rcu+0xf4/0x1c0 kernel/softirq.c:637 irq_exit_rcu+0x9/0x30 kernel/softirq.c:649 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1049 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:preempt_schedule_irq+0xf6/0x1c0 kernel/sched/core.c:7015 Code: 89 f5 49 c1 ed 03 eb 0d 48 f7 03 08 00 00 00 0f 84 8b 00 00 00 bf 01 00 00 00 e8 c5 42 93 f5 e8 50 b5 cc f5 fb bf 01 00 00 00 85 ab ff ff 43 80 7c 3d 00 00 74 08 4c 89 f7 e8 a5 cb 2e f6 48 RSP: 0018:ffffc900043678e0 EFLAGS: 00000282 RAX: 47e92bc5f8f39f00 RBX: 1ffff9200086cf24 RCX: ffffffff8170cfaa RDX: dffffc0000000000 RSI: ffffffff8c0acac0 RDI: 0000000000000001 RBP: ffffc900043679a0 R08: ffffffff942d0897 R09: 1ffffffff285a112 R10: dffffc0000000000 R11: fffffbfff285a113 R12: 1ffff9200086cf1c R13: 1ffff9200086cf20 R14: ffffc90004367900 R15: dffffc0000000000 irqentry_exit+0x5e/0x90 kernel/entry/common.c:354 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:should_resched arch/x86/include/asm/preempt.h:103 [inline] RIP: 0010:__local_bh_enable_ip+0x170/0x200 kernel/softirq.c:389 Code: 8c e8 14 69 70 0a 65 66 8b 05 24 4a ac 7e 66 85 c0 75 5d bf 01 00 00 00 e8 2d b2 0b 00 e8 18 23 45 00 fb 65 8b 05 e8 49 ac 7e <85> c0 75 05 e8 a7 28 a9 ff 48 c7 44 24 20 0e 36 e0 45 49 c7 04 1c RSP: 0018:ffffc90004367a60 EFLAGS: 00000286 RAX: 0000000080000000 RBX: 1ffff9200086cf50 RCX: ffffffff8170cfaa RDX: dffffc0000000000 RSI: ffffffff8c0acac0 RDI: ffffffff8c610ce0 RBP: ffffc90004367b20 R08: ffffffff942d0897 R09: 1ffffffff285a112 R10: dffffc0000000000 R11: fffffbfff285a113 R12: dffffc0000000000 R13: 1ffff9200086cf54 R14: ffffc90004367aa0 R15: 0000000000000201 neigh_periodic_work+0xb35/0xd50 net/core/neighbour.c:1019 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa65/0x1850 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 kthread+0x2f2/0x390 kernel/kthread.c:389 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 IPVS: ovf: UDP 224.0.0.2:0 - no destination available IPVS: ovf: UDP 224.0.0.2:0 - no destination available IPVS: ovf: UDP 224.0.0.2:0 - no destination available IPVS: ovf: UDP 224.0.0.2:0 - no destination available IPVS: ovf: UDP 224.0.0.2:0 - no destination available IPVS: ovf: UDP 224.0.0.2:0 - no destination available IPVS: ovf: UDP 224.0.0.2:0 - no destination available IPVS: ovf: UDP 224.0.0.2:0 - no destination available IPVS: ovf: UDP 224.0.0.2:0 - no destination available