rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 1-...!: (2 ticks this GP) idle=d52c/1/0x4000000000000000 softirq=15406/15406 fqs=0 rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P35/1:b..l P5828/1:b..l rcu: (detected by 0, t=10502 jiffies, g=10505, q=496 ncpus=2) Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 5206 Comm: udevd Not tainted 6.13.0-rc1-syzkaller-00182-g0f6ede9fbc74 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:variable_test_bit arch/x86/include/asm/bitops.h:227 [inline] RIP: 0010:arch_test_bit arch/x86/include/asm/bitops.h:239 [inline] RIP: 0010:_test_bit include/asm-generic/bitops/instrumented-non-atomic.h:142 [inline] RIP: 0010:hlock_class kernel/locking/lockdep.c:228 [inline] RIP: 0010:__lock_acquire+0x12b6/0x2100 kernel/locking/lockdep.c:5223 Code: 62 0a 00 00 48 8b 44 24 10 8b 18 81 e3 ff 1f 00 00 48 89 d8 48 c1 e8 06 48 8d 3c c5 80 88 2b 94 be 08 00 00 00 e8 aa 97 8f 00 <48> 0f a3 1d c2 c3 b0 12 73 1d 48 69 c3 c8 00 00 00 48 8d 98 40 07 RSP: 0018:ffffc90000a18a10 EFLAGS: 00000056 RAX: 0000000000000001 RBX: 0000000000000021 RCX: ffffffff817ac4b6 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff942b8880 RBP: 58cce5e7c8d5ebdc R08: ffffffff942b8887 R09: 1ffffffff2857110 R10: dffffc0000000000 R11: fffffbfff2857111 R12: ffff88807d059e00 R13: ffff88807d059e00 R14: 1ffff1100fa0b52a R15: 0000000000000001 FS: 00007fa43f54fc80(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fe4a7c756c0 CR3: 0000000034314000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 rcu_lock_acquire include/linux/rcupdate.h:337 [inline] rcu_read_lock include/linux/rcupdate.h:849 [inline] advance_sched+0xa1e/0xca0 net/sched/sch_taprio.c:985 __run_hrtimer kernel/time/hrtimer.c:1739 [inline] __hrtimer_run_queues+0x59b/0xd30 kernel/time/hrtimer.c:1803 hrtimer_interrupt+0x403/0xa40 kernel/time/hrtimer.c:1865 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:fast_dput+0xd8/0x420 fs/dcache.c:821 Code: 4a 7c ff e9 2b 01 00 00 e8 45 4a 7c ff 4c 89 f7 e8 ad e3 af 09 49 bf 00 00 00 00 00 fc ff df 49 8d ac 24 f8 00 00 00 48 89 e8 <48> c1 e8 03 42 0f b6 04 38 84 c0 0f 85 84 02 00 00 8b 5d 00 31 ff RSP: 0018:ffffc900032c7ab0 EFLAGS: 00000246 RAX: ffff8880277bd9f0 RBX: 1ffff11004ef7b3e RCX: ffff88807d059e00 RDX: 0000000000000000 RSI: 0000000000000059 RDI: 0000000000000001 RBP: ffff8880277bd9f0 R08: ffffffff82232953 R09: fffff52000658f44 R10: dffffc0000000000 R11: fffff52000658f44 R12: ffff8880277bd8f8 R13: dffffc0000000000 R14: ffff8880277bd9b0 R15: dffffc0000000000 dput+0xe8/0x2b0 fs/dcache.c:861 path_put fs/namei.c:625 [inline] terminate_walk+0x30d/0x430 fs/namei.c:755 path_lookupat+0x328/0x450 fs/namei.c:2651 filename_lookup+0x2a3/0x670 fs/namei.c:2663 do_readlinkat+0xf0/0x3a0 fs/stat.c:562 __do_sys_readlink fs/stat.c:599 [inline] __se_sys_readlink fs/stat.c:596 [inline] __x64_sys_readlink+0x7f/0x90 fs/stat.c:596 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: 0033:0x7fa43f117d47 Code: 73 01 c3 48 8b 0d e1 90 0d 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 59 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d b1 90 0d 00 f7 d8 64 89 01 48 RSP: 002b:00007fff35329fb8 EFLAGS: 00000246 ORIG_RAX: 0000000000000059 RAX: ffffffffffffffda RBX: 00007fff35329fc8 RCX: 00007fa43f117d47 RDX: 0000000000000400 RSI: 00007fff35329fc8 RDI: 00007fff3532a4a8 RBP: 0000000000000400 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000007 R11: 0000000000000246 R12: 00007fff3532a4a8 R13: 00007fff3532a418 R14: 00005629f00d9910 R15: 0000000000000000 task:syz-executor state:R running task stack:18352 pid:5828 tgid:5828 ppid:5823 flags:0x00000000 Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0x1850/0x4c30 kernel/sched/core.c:6756 preempt_schedule_common+0x84/0xd0 kernel/sched/core.c:6935 preempt_schedule+0xe1/0xf0 kernel/sched/core.c:6959 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] copy_pte_range mm/memory.c:1200 [inline] copy_pmd_range+0x74aa/0x7eb0 mm/memory.c:1261 copy_pud_range mm/memory.c:1298 [inline] copy_p4d_range mm/memory.c:1322 [inline] copy_page_range+0x99f/0xe90 mm/memory.c:1420 dup_mmap kernel/fork.c:751 [inline] dup_mm kernel/fork.c:1695 [inline] copy_mm+0x11c7/0x1f90 kernel/fork.c:1744 copy_process+0x1845/0x3d50 kernel/fork.c:2395 kernel_clone+0x226/0x8e0 kernel/fork.c:2807 __do_sys_clone kernel/fork.c:2950 [inline] __se_sys_clone kernel/fork.c:2934 [inline] __x64_sys_clone+0x258/0x2a0 kernel/fork.c:2934 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: 0033:0x7fe4a6f76753 RSP: 002b:00007ffc1018a998 EFLAGS: 00000246 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fe4a6f76753 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000 R10: 000055558db337d0 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000014e7f R14: 0000000000014cd2 R15: 00007ffc1018ab20 task:kworker/u8:2 state:R running task stack:20976 pid:35 tgid:35 ppid:2 flags:0x00004000 Workqueue: bat_events batadv_nc_worker Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0x1850/0x4c30 kernel/sched/core.c:6756 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:7078 irqentry_exit+0x5e/0x90 kernel/entry/common.c:354 asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:707 RIP: 0010:lock_acquire+0x264/0x550 kernel/locking/lockdep.c:5853 Code: 2b 00 74 08 4c 89 f7 e8 5a ac 8f 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:ffffc90000ab79e0 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 1ffff92000156f48 RCX: ffff88801dea28d8 RDX: dffffc0000000000 RSI: ffffffff8c0aa880 RDI: ffffffff8c5f63e0 RBP: ffffc90000ab7b40 R08: ffffffff942b8887 R09: 1ffffffff2857110 R10: dffffc0000000000 R11: fffffbfff2857111 R12: 1ffff92000156f44 R13: dffffc0000000000 R14: ffffc90000ab7a40 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:3229 [inline] process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g10505 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=1 timer-softirq=3674 rcu: rcu_preempt kthread starved for 10502 jiffies! g10505 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:25360 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0x1850/0x4c30 kernel/sched/core.c:6756 __schedule_loop kernel/sched/core.c:6833 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6848 schedule_timeout+0x15a/0x290 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2045 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2247 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244