rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 1-...!: (0 ticks this GP) idle=4274/1/0x4000000000000000 softirq=91502/91502 fqs=0 rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P21661/1:b..l P7296/1:b..l rcu: (detected by 0, t=10505 jiffies, g=89517, q=228 ncpus=2) Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 21700 Comm: syz.8.4337 Not tainted 6.14.0-rc1-syzkaller-00276-g69b54314c975 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 RIP: 0010:do_raw_spin_lock+0xa/0x370 kernel/locking/spinlock_debug.c:114 Code: 7c 91 48 89 df e8 b6 4f 87 00 eb 87 0f 1f 40 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 55 48 89 e5 41 57 <41> 56 41 55 41 54 53 48 83 e4 e0 48 81 ec a0 00 00 00 49 89 fc 65 RSP: 0018:ffffc90000a18c88 EFLAGS: 00000096 RAX: 2f4db5dbedaf9900 RBX: 1ffff92000143198 RCX: ffff88802b2a64e8 RDX: dffffc0000000000 RSI: ffffffff8c0ab8e0 RDI: ffff8880b872c500 RBP: ffffc90000a18c90 R08: ffffffff942c684f R09: 1ffffffff2858d09 R10: dffffc0000000000 R11: fffffbfff2858d0a R12: ffff8880b872c500 R13: 1ffff92000143194 R14: ffffc90000a18cc0 R15: dffffc0000000000 FS: 00005555647fd500(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b2d00eff8 CR3: 000000006cc8a000 CR4: 00000000003526f0 DR0: 0000000000000007 DR1: 000000000000000b DR2: 0000000000000002 DR3: 0000000000000010 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __raw_spin_lock_irq include/linux/spinlock_api_smp.h:120 [inline] _raw_spin_lock_irq+0xdf/0x120 kernel/locking/spinlock.c:170 __run_hrtimer kernel/time/hrtimer.c:1805 [inline] __hrtimer_run_queues+0x670/0xd30 kernel/time/hrtimer.c:1865 hrtimer_interrupt+0x403/0xa40 kernel/time/hrtimer.c:1927 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline] __sysvec_apic_timer_interrupt+0x110/0x420 arch/x86/kernel/apic/apic.c:1055 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1049 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:check_preemption_disabled+0x2/0x120 lib/smp_processor_id.c:13 Code: b7 5f 8c 48 c7 c6 60 b7 5f 8c eb 1c 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 41 57 <41> 56 41 54 53 48 83 ec 10 65 48 8b 04 25 28 00 00 00 48 89 44 24 RSP: 0018:ffffc900056ef730 EFLAGS: 00000246 RAX: ffffc900056ef8b0 RBX: ffff88802b2a6ed8 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffff8c5fb760 RDI: ffffffff8c5fb720 RBP: ffffc900056ef930 R08: ffffc900056ef8bf R09: 0000000000000000 R10: ffffc900056ef8b0 R11: fffff52000addf18 R12: ffffc900056ef8b0 R13: 0000000000000001 R14: dffffc0000000000 R15: dffffc0000000000 __schedule+0xbb/0x4c40 kernel/sched/core.c:6658 preempt_schedule_common+0x84/0xd0 kernel/sched/core.c:6943 preempt_schedule+0xe1/0xf0 kernel/sched/core.c:6967 preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk.S:12 class_preempt_destructor include/linux/preempt.h:480 [inline] try_to_wake_up+0x9c3/0x1470 kernel/sched/core.c:4336 wake_up_process kernel/sched/core.c:4462 [inline] wake_up_q+0xc8/0x120 kernel/sched/core.c:1074 futex_wake+0x523/0x5c0 kernel/futex/waitwake.c:199 do_futex+0x392/0x560 kernel/futex/syscalls.c:107 __do_sys_futex kernel/futex/syscalls.c:179 [inline] __se_sys_futex+0x3f9/0x480 kernel/futex/syscalls.c:160 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: 0033:0x7fd0be98cde9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffd195da988 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: ffffffffffffffda RBX: 00007fd0beba5fa8 RCX: 00007fd0be98cde9 RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007fd0beba5fa8 RBP: 0000000000000000 R08: 0000000000000000 R09: 00000017195dac7f R10: 00007fd0beba5fa0 R11: 0000000000000246 R12: 00007fd0beba5fac R13: 00007fd0beba5fa0 R14: 00000000000011cc R15: 0000000000000004 task:kworker/u8:26 state:R running task stack:20784 pid:7296 tgid:7296 ppid:2 task_flags:0x4208060 flags:0x00004000 Workqueue: bat_events batadv_nc_worker Call Trace: context_switch kernel/sched/core.c:5377 [inline] __schedule+0x18bc/0x4c40 kernel/sched/core.c:6764 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:7086 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:lock_acquire+0x264/0x550 kernel/locking/lockdep.c:5855 Code: 2b 00 74 08 4c 89 f7 e8 1a b6 88 00 f6 44 24 61 02 0f 85 85 01 00 00 41 f7 c7 00 02 00 00 74 01 fb 48 c7 44 24 40 0e 36 e0 45 <4b> c7 44 25 00 00 00 00 00 43 c7 44 25 09 00 00 00 00 43 c7 44 25 RSP: 0018:ffffc90003db7940 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 1ffff920007b6f34 RCX: ffff888068c246e8 RDX: dffffc0000000000 RSI: ffffffff8c0ab8e0 RDI: ffffffff8c5fb780 RBP: ffffc90003db7aa0 R08: ffffffff942c6847 R09: 1ffffffff2858d08 R10: dffffc0000000000 R11: fffffbfff2858d09 R12: 1ffff920007b6f30 R13: dffffc0000000000 R14: ffffc90003db79a0 R15: 0000000000000246 rcu_lock_acquire include/linux/rcupdate.h:337 [inline] rcu_read_lock include/linux/rcupdate.h:849 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline] batadv_nc_worker+0xec/0x610 net/batman-adv/network-coding.c:719 process_one_work kernel/workqueue.c:3236 [inline] process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3317 worker_thread+0x870/0xd30 kernel/workqueue.c:3398 kthread+0x7a9/0x920 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 task:syz.2.4324 state:R running task stack:24128 pid:21661 tgid:21661 ppid:13976 task_flags:0x40044c flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5377 [inline] __schedule+0x18bc/0x4c40 kernel/sched/core.c:6764 preempt_schedule_common+0x84/0xd0 kernel/sched/core.c:6943 preempt_schedule+0xe1/0xf0 kernel/sched/core.c:6967 preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk.S:12 unwind_next_frame+0x18f8/0x22d0 arch/x86/kernel/unwind_orc.c:672 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x118/0x1d0 kernel/stacktrace.c:122 save_stack+0xfb/0x1f0 mm/page_owner.c:156 __reset_page_owner+0x76/0x430 mm/page_owner.c:297 reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1127 [inline] free_unref_folios+0xe2f/0x18a0 mm/page_alloc.c:2707 folios_put_refs+0x76c/0x860 mm/swap.c:994 folio_batch_release include/linux/pagevec.h:101 [inline] shmem_undo_range+0x593/0x1820 mm/shmem.c:1112 shmem_truncate_range mm/shmem.c:1224 [inline] shmem_evict_inode+0x29b/0xa80 mm/shmem.c:1352 evict+0x4e8/0x9a0 fs/inode.c:796 __dentry_kill+0x20d/0x630 fs/dcache.c:643 dput+0x19f/0x2b0 fs/dcache.c:885 __fput+0x60b/0x9f0 fs/file_table.c:472 task_work_run+0x24f/0x310 kernel/task_work.c:227 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0xa2a/0x28e0 kernel/exit.c:938 do_group_exit+0x207/0x2c0 kernel/exit.c:1087 get_signal+0x16b2/0x1750 kernel/signal.c:3036 arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0xce/0x340 kernel/entry/common.c:218 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f992c78ce23 RSP: 002b:00007ffea507c1a8 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 RAX: 00007f992d564000 RBX: 00007f992adf76c0 RCX: 00007f992c78ce23 RDX: 0000000000000000 RSI: 0000000000021000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 00000000ffffffff R09: 0000000000000000 R10: 0000000000020022 R11: 0000000000000246 R12: 00007ffea507c300 R13: ffffffffffffffc0 R14: 0000000000001000 R15: 0000000000000000 rcu: rcu_preempt kthread timer wakeup didn't happen for 10504 jiffies! g89517 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=1 timer-softirq=148724 rcu: rcu_preempt kthread starved for 10505 jiffies! g89517 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:25072 pid:17 tgid:17 ppid:2 task_flags:0x208040 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5377 [inline] __schedule+0x18bc/0x4c40 kernel/sched/core.c:6764 __schedule_loop kernel/sched/core.c:6841 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6856 schedule_timeout+0x15a/0x290 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2024 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2226 kthread+0x7a9/0x920 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244