rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 0-...!: (1 GPs behind) idle=25b4/1/0x4000000000000000 softirq=91965/91970 fqs=8 rcu: (detected by 1, t=10505 jiffies, g=86277, q=2010 ncpus=2) Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 18355 Comm: kworker/u8:1 Not tainted 6.12.0-syzkaller-10553-gb86545e02e8c #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: bat_events batadv_nc_worker RIP: 0010:__lock_release kernel/locking/lockdep.c:5553 [inline] RIP: 0010:lock_release+0x2f0/0x6f0 kernel/locking/lockdep.c:5870 Code: 66 83 6d 22 20 66 83 7d 22 1f 0f 87 cd 00 00 00 4c 89 f2 44 8b 64 24 50 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 0f b6 04 02 <84> c0 74 08 3c 03 0f 8e f4 02 00 00 48 89 ea 45 89 a7 d8 0a 00 00 RSP: 0018:ffffc90000007ca8 EFLAGS: 00000802 RAX: 0000000000000000 RBX: 1ffff92000000f97 RCX: ffffc90000007cf8 RDX: 1ffff110054a05e3 RSI: ffff88805bf87300 RDI: ffff88802a502f92 RBP: ffff88802a502f70 R08: 0000000000000000 R09: fffffbfff20c1852 R10: ffffffff9060c297 R11: 0000000000000002 R12: 0000000000000002 R13: 0000000000000003 R14: ffff88802a502f18 R15: ffff88802a502440 FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000110c34ac9d CR3: 000000004d544000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __raw_spin_unlock include/linux/spinlock_api_smp.h:141 [inline] _raw_spin_unlock+0x16/0x50 kernel/locking/spinlock.c:186 spin_unlock include/linux/spinlock.h:391 [inline] advance_sched+0x611/0xc60 net/sched/sch_taprio.c:981 __run_hrtimer kernel/time/hrtimer.c:1739 [inline] __hrtimer_run_queues+0x20a/0xae0 kernel/time/hrtimer.c:1803 hrtimer_interrupt+0x392/0x8e0 kernel/time/hrtimer.c:1865 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline] __sysvec_apic_timer_interrupt+0x10f/0x400 arch/x86/kernel/apic/apic.c:1055 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0x9f/0xc0 arch/x86/kernel/apic/apic.c:1049 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:lock_release+0x3e5/0x6f0 kernel/locking/lockdep.c:5857 Code: 7e 83 f8 01 0f 85 fe 01 00 00 9c 58 f6 c4 02 0f 85 e9 01 00 00 48 f7 04 24 00 02 00 00 74 01 fb 48 b8 00 00 00 00 00 fc ff df <48> 01 c3 48 c7 03 00 00 00 00 c7 43 08 00 00 00 00 48 8b 84 24 88 RSP: 0018:ffffc90000117ac8 EFLAGS: 00000206 RAX: dffffc0000000000 RBX: 1ffff92000022f5b RCX: ffffc90000117b18 RDX: 1ffff110054a05e2 RSI: ffffffff8b6ce300 RDI: ffffffff8bd1e4c0 RBP: 64e6e35b54a57c85 R08: 0000000000000000 R09: fffffbfff20c1852 R10: ffffffff9060c297 R11: 0000000000000002 R12: 0000000000000002 R13: 0000000000000003 R14: ffff88802a502f18 R15: ffff88802a502440 rcu_lock_release include/linux/rcupdate.h:347 [inline] rcu_read_unlock include/linux/rcupdate.h:880 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:412 [inline] batadv_nc_worker+0x88c/0x1060 net/batman-adv/network-coding.c:719 process_one_work+0x9c5/0x1ba0 kernel/workqueue.c:3229 process_scheduled_works kernel/workqueue.c:3310 [inline] worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 rcu: rcu_preempt kthread starved for 10465 jiffies! g86277 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->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:R running task stack:27600 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0xe58/0x5ad0 kernel/sched/core.c:6756 __schedule_loop kernel/sched/core.c:6833 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6848 schedule_timeout+0x124/0x280 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x1eb/0xb00 kernel/rcu/tree.c:2045 rcu_gp_kthread+0x271/0x380 kernel/rcu/tree.c:2247 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 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: CPU: 1 UID: 0 PID: 17285 Comm: syz-executor Not tainted 6.12.0-syzkaller-10553-gb86545e02e8c #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:check_kcov_mode kernel/kcov.c:185 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x3b/0x70 kernel/kcov.c:217 Code: 75 7e a9 00 01 ff 00 48 8b 34 24 74 1d f6 c4 01 74 43 a9 00 00 0f 00 75 3c a9 00 00 f0 00 75 35 8b 82 1c 16 00 00 85 c0 74 2b <8b> 82 f8 15 00 00 83 f8 02 75 20 48 8b 8a 00 16 00 00 8b 92 fc 15 RSP: 0018:ffffc900034d7988 EFLAGS: 00000246 RAX: 0000000000000002 RBX: ffff8880b86469c0 RCX: ffffffff8182b0bc RDX: ffff88806addc880 RSI: ffffffff8182b096 RDI: 0000000000000005 RBP: 0000000000000003 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: ffffed10170c8d39 R13: 0000000000000001 R14: ffff8880b86469c8 R15: ffff8880b873fe40 FS: 000055558a1ba500(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f19d79b0d58 CR3: 000000004d544000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rep_nop arch/x86/include/asm/vdso/processor.h:13 [inline] cpu_relax arch/x86/include/asm/vdso/processor.h:18 [inline] csd_lock_wait kernel/smp.c:340 [inline] smp_call_function_many_cond+0x456/0x1300 kernel/smp.c:884 on_each_cpu_cond_mask+0x40/0x90 kernel/smp.c:1051 __flush_tlb_multi arch/x86/include/asm/paravirt.h:91 [inline] flush_tlb_multi arch/x86/mm/tlb.c:938 [inline] flush_tlb_mm_range+0x289/0x330 arch/x86/mm/tlb.c:1024 dup_mmap kernel/fork.c:779 [inline] dup_mm kernel/fork.c:1695 [inline] copy_mm kernel/fork.c:1744 [inline] copy_process+0x72ec/0x8df0 kernel/fork.c:2395 kernel_clone+0xfd/0x960 kernel/fork.c:2807 __do_sys_clone+0xba/0x100 kernel/fork.c:2950 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fe194977053 Code: 1f 84 00 00 00 00 00 64 48 8b 04 25 10 00 00 00 45 31 c0 31 d2 31 f6 bf 11 00 20 01 4c 8d 90 d0 02 00 00 b8 38 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 35 89 c2 85 c0 75 2c 64 48 8b 04 25 10 00 00 RSP: 002b:00007ffca9512da8 EFLAGS: 00000246 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fe194977053 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000 R10: 000055558a1ba7d0 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000012747b R14: 0000000000126db9 R15: 00007ffca9512f30