rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 0-...!: (1 GPs behind) idle=b074/1/0x4000000000000000 softirq=41463/41464 fqs=4 rcu: (detected by 1, t=10502 jiffies, g=68677, q=178 ncpus=2) Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 61 Comm: kworker/u8:5 Not tainted 6.9.0-rc4-syzkaller-00329-g48cf398f15fc #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 Workqueue: bat_events batadv_nc_worker RIP: 0010:check_preemption_disabled+0x1d/0xe0 lib/smp_processor_id.c:56 Code: 90 90 90 90 90 90 90 90 90 90 90 90 90 41 54 55 53 48 83 ec 08 65 8b 1d 6d a6 28 75 65 8b 05 62 a6 28 75 a9 ff ff ff 7f 74 0f <48> 83 c4 08 89 d8 5b 5d 41 5c c3 cc cc cc cc 9c 58 f6 c4 02 74 ea RSP: 0018:ffffc90000007dc8 EFLAGS: 00000002 RAX: 0000000080010001 RBX: 0000000000000000 RCX: 0000000000000001 RDX: 0000000000000000 RSI: ffffffff8b0cb0c0 RDI: ffffffff8b6f5720 RBP: ffff8880b942c9d8 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: ffffffff8b0f37c0 R12: ffff888016f79e00 R13: 00000000ffffffff R14: 00000000ffffffff R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b9400000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020003c80 CR3: 0000000021cfe000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lockdep_recursion_inc kernel/locking/lockdep.c:462 [inline] lock_is_held_type+0x67/0x150 kernel/locking/lockdep.c:5824 lock_is_held include/linux/lockdep.h:231 [inline] __run_hrtimer kernel/time/hrtimer.c:1658 [inline] __hrtimer_run_queues+0x960/0xcc0 kernel/time/hrtimer.c:1756 hrtimer_interrupt+0x31b/0x800 kernel/time/hrtimer.c:1818 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1032 [inline] __sysvec_apic_timer_interrupt+0x10f/0x450 arch/x86/kernel/apic/apic.c:1049 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline] sysvec_apic_timer_interrupt+0x90/0xb0 arch/x86/kernel/apic/apic.c:1043 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:lock_acquire+0x1f2/0x560 kernel/locking/lockdep.c:5722 Code: c1 05 ca 9f 96 7e 83 f8 01 0f 85 ea 02 00 00 9c 58 f6 c4 02 0f 85 d5 02 00 00 48 85 ed 74 01 fb 48 b8 00 00 00 00 00 fc ff df <48> 01 c3 48 c7 03 00 00 00 00 48 c7 43 08 00 00 00 00 48 8b 84 24 RSP: 0018:ffffc900015d7aa8 EFLAGS: 00000206 RAX: dffffc0000000000 RBX: 1ffff920002baf57 RCX: 0000000002cca6f8 RDX: 0000000000000001 RSI: ffffffff8b0cb100 RDI: ffffffff8b6f5720 RBP: 0000000000000200 R08: 0000000000000000 R09: fffffbfff27bb030 R10: ffffffff93dd8187 R11: 0000000000000002 R12: 0000000000000000 R13: 0000000000000000 R14: ffffffff8d7b0e20 R15: 0000000000000000 rcu_lock_acquire include/linux/rcupdate.h:329 [inline] rcu_read_lock include/linux/rcupdate.h:781 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline] batadv_nc_worker+0x16e/0x10f0 net/batman-adv/network-coding.c:719 process_one_work+0x9a9/0x1ac0 kernel/workqueue.c:3254 process_scheduled_works kernel/workqueue.c:3335 [inline] worker_thread+0x6c8/0xf70 kernel/workqueue.c:3416 kthread+0x2c1/0x3a0 kernel/kthread.c:388 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 10475 jiffies! g68677 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:27664 pid:16 tgid:16 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5409 [inline] __schedule+0xf15/0x5d00 kernel/sched/core.c:6746 __schedule_loop kernel/sched/core.c:6823 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6838 schedule_timeout+0x136/0x2a0 kernel/time/timer.c:2582 rcu_gp_fqs_loop+0x1eb/0xb00 kernel/rcu/tree.c:1663 rcu_gp_kthread+0x271/0x380 kernel/rcu/tree.c:1862 kthread+0x2c1/0x3a0 kernel/kthread.c:388 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 PID: 10676 Comm: syz-executor.2 Not tainted 6.9.0-rc4-syzkaller-00329-g48cf398f15fc #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 RIP: 0010:csd_lock_wait kernel/smp.c:311 [inline] RIP: 0010:smp_call_function_many_cond+0x4e7/0x1420 kernel/smp.c:855 Code: 0c 00 85 ed 74 4d 48 b8 00 00 00 00 00 fc ff df 4d 89 f4 4c 89 f5 49 c1 ec 03 83 e5 07 49 01 c4 83 c5 03 e8 5b 07 0c 00 f3 90 <41> 0f b6 04 24 40 38 c5 7c 08 84 c0 0f 85 f7 0c 00 00 8b 43 08 31 RSP: 0018:ffffc90003447818 EFLAGS: 00000293 RAX: 0000000000000000 RBX: ffff8880b9446860 RCX: ffffffff8181bb1b RDX: ffff888056295a00 RSI: ffffffff8181baf5 RDI: 0000000000000005 RBP: 0000000000000003 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000001 R12: ffffed1017288d0d R13: 0000000000000001 R14: ffff8880b9446868 R15: ffff8880b953fc00 FS: 0000000000000000(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fc7a0152f00 CR3: 000000006558e000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: on_each_cpu_cond_mask+0x40/0x90 kernel/smp.c:1023 __flush_tlb_multi arch/x86/include/asm/paravirt.h:91 [inline] flush_tlb_multi arch/x86/mm/tlb.c:941 [inline] flush_tlb_mm_range+0x293/0x330 arch/x86/mm/tlb.c:1027 tlb_flush arch/x86/include/asm/tlb.h:20 [inline] tlb_flush_mmu_tlbonly include/asm-generic/tlb.h:465 [inline] tlb_flush_mmu_tlbonly include/asm-generic/tlb.h:455 [inline] tlb_flush_mmu mm/mmu_gather.c:372 [inline] tlb_finish_mmu+0x3c9/0x7b0 mm/mmu_gather.c:465 exit_mmap+0x3da/0xb90 mm/mmap.c:3280 __mmput+0x12a/0x4d0 kernel/fork.c:1346 mmput+0x62/0x70 kernel/fork.c:1368 exit_mm kernel/exit.c:569 [inline] do_exit+0x999/0x2c10 kernel/exit.c:865 do_group_exit+0xd3/0x2a0 kernel/exit.c:1027 get_signal+0x2616/0x2710 kernel/signal.c:2911 arch_do_signal_or_restart+0x90/0x7e0 arch/x86/kernel/signal.c:310 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x14a/0x2a0 kernel/entry/common.c:218 do_syscall_64+0xdc/0x260 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fc79f47dea9 Code: Unable to access opcode bytes at 0x7fc79f47de7f. RSP: 002b:00007fc7a0195178 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: 0000000000000000 RBX: 00007fc79f5ac058 RCX: 00007fc79f47dea9 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007fc79f5ac058 RBP: 00007fc79f5ac050 R08: 00007fc7a01956c0 R09: 00007fc7a01956c0 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fc79f5ac05c R13: 000000000000000b R14: 00007ffca19c2920 R15: 00007ffca19c2a08