rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 1-...!: (1 GPs behind) idle=8e8c/1/0x4000000000000000 softirq=53197/53212 fqs=444 rcu: (detected by 0, t=10506 jiffies, g=54517, q=269 ncpus=2) Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 1167 Comm: kworker/u8:6 Not tainted 6.14.0-rc1-syzkaller-00026-gd009de7d5428 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 Workqueue: bat_events batadv_nc_worker RIP: 0010:bytes_is_nonzero mm/kasan/generic.c:87 [inline] RIP: 0010:memory_is_nonzero mm/kasan/generic.c:104 [inline] RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:129 [inline] RIP: 0010:memory_is_poisoned mm/kasan/generic.c:161 [inline] RIP: 0010:check_region_inline mm/kasan/generic.c:180 [inline] RIP: 0010:kasan_check_range+0x111/0x1a0 mm/kasan/generic.c:189 Code: 44 89 c2 e8 c1 ec ff ff 83 f0 01 5b 5d 41 5c c3 cc cc cc cc 48 85 d2 74 4f 48 01 ea eb 09 48 83 c0 01 48 39 d0 74 41 80 38 00 <74> f2 eb b2 41 bc 08 00 00 00 45 29 dc 49 8d 14 2c eb 0c 48 83 c0 RSP: 0018:ffffc90000a18b08 EFLAGS: 00000046 RAX: fffffbfff2dd75cd RBX: fffffbfff2dd75ce RCX: ffffffff8195b23e RDX: fffffbfff2dd75ce RSI: 0000000000000008 RDI: ffffffff96ebae68 RBP: fffffbfff2dd75cd R08: 0000000000000000 R09: fffffbfff2dd75cd R10: ffffffff96ebae6f R11: 0000000000000004 R12: 0000000000000002 R13: ffff88802823a440 R14: 0000000000000d75 R15: ffff88802823afa8 FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fe1b0127440 CR3: 000000000df80000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000280 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: instrument_atomic_read include/linux/instrumented.h:68 [inline] _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline] hlock_class+0x4e/0x130 kernel/locking/lockdep.c:230 check_wait_context kernel/locking/lockdep.c:4853 [inline] __lock_acquire+0x44d/0x3c40 kernel/locking/lockdep.c:5178 lock_acquire.part.0+0x11b/0x380 kernel/locking/lockdep.c:5851 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:351 [inline] advance_sched+0xd8/0xc60 net/sched/sch_taprio.c:924 __run_hrtimer kernel/time/hrtimer.c:1801 [inline] __hrtimer_run_queues+0x20a/0xae0 kernel/time/hrtimer.c:1865 hrtimer_interrupt+0x392/0x8e0 kernel/time/hrtimer.c:1927 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_acquire.part.0+0x155/0x380 kernel/locking/lockdep.c:5816 Code: b8 ff ff ff ff 65 0f c1 05 80 de 6b 7e 83 f8 01 0f 85 d0 01 00 00 9c 58 f6 c4 02 0f 85 e5 01 00 00 48 85 ed 0f 85 b6 01 00 00 <48> b8 00 00 00 00 00 fc ff df 48 01 c3 48 c7 03 00 00 00 00 48 c7 RSP: 0018:ffffc9000431f9d0 EFLAGS: 00000206 RAX: 0000000000000046 RBX: 1ffff92000863f3b RCX: 0000000040e1fbc0 RDX: 0000000000000001 RSI: ffffffff8b6cf020 RDI: ffffffff8bd34c80 RBP: 0000000000000200 R08: 0000000000000000 R09: fffffbfff2dd7598 R10: ffffffff96ebacc7 R11: 0000000000000002 R12: 0000000000000000 R13: ffffffff8e1bcc80 R14: 0000000000000000 R15: 0000000000000000 rcu_lock_acquire include/linux/rcupdate.h:337 [inline] rcu_read_lock include/linux/rcupdate.h:849 [inline] batadv_nc_process_nc_paths.part.0+0xe4/0x3e0 net/batman-adv/network-coding.c:687 batadv_nc_process_nc_paths net/batman-adv/network-coding.c:679 [inline] batadv_nc_worker+0xcc8/0x1060 net/batman-adv/network-coding.c:728 process_one_work+0x9c5/0x1ba0 kernel/workqueue.c:3236 process_scheduled_works kernel/workqueue.c:3317 [inline] worker_thread+0x6c8/0xf00 kernel/workqueue.c:3398 kthread+0x3af/0x750 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 rcu: rcu_preempt kthread starved for 6565 jiffies! g54517 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:28048 pid:17 tgid:17 ppid:2 task_flags:0x208040 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5377 [inline] __schedule+0xf43/0x5890 kernel/sched/core.c:6764 __schedule_loop kernel/sched/core.c:6841 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6856 schedule_timeout+0x124/0x280 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x1eb/0xb00 kernel/rcu/tree.c:2024 rcu_gp_kthread+0x271/0x380 kernel/rcu/tree.c:2226 kthread+0x3af/0x750 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 rcu: Stack dump where RCU GP kthread last ran: CPU: 0 UID: 0 PID: 14097 Comm: syz.4.2383 Not tainted 6.14.0-rc1-syzkaller-00026-gd009de7d5428 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 RIP: 0010:csd_lock_wait kernel/smp.c:340 [inline] RIP: 0010:smp_call_function_many_cond+0x4ea/0x12c0 kernel/smp.c:885 Code: fc 04 0c 00 f3 90 41 0f b6 04 24 40 38 c5 7c 08 84 c0 0f 85 e8 0b 00 00 8b 43 08 31 ff 83 e0 01 41 89 c5 89 c6 e8 d6 ff 0b 00 <45> 85 ed 75 d0 e8 cc 04 0c 00 e8 c7 04 0c 00 44 8b 6c 24 04 bf 07 RSP: 0018:ffffc9001c4df4f0 EFLAGS: 00000293 RAX: 0000000000000000 RBX: ffff8880b8744a80 RCX: ffffffff81adcd3a RDX: ffff88807beac880 RSI: 0000000000000000 RDI: 0000000000000005 RBP: 0000000000000003 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000003 R12: ffffed10170e8951 R13: 0000000000000001 R14: ffff8880b863fe80 R15: ffff8880b8744a88 FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f058be81261 CR3: 0000000045954000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 000000000000000c DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: on_each_cpu_cond_mask+0x40/0x90 kernel/smp.c:1052 __flush_tlb_multi arch/x86/include/asm/paravirt.h:91 [inline] flush_tlb_multi arch/x86/mm/tlb.c:966 [inline] flush_tlb_mm_range+0x271/0x4a0 arch/x86/mm/tlb.c:1054 tlb_flush arch/x86/include/asm/tlb.h:20 [inline] tlb_flush_mmu_tlbonly include/asm-generic/tlb.h:481 [inline] tlb_flush_mmu_tlbonly include/asm-generic/tlb.h:471 [inline] zap_pte_range mm/memory.c:1758 [inline] zap_pmd_range mm/memory.c:1823 [inline] zap_pud_range mm/memory.c:1852 [inline] zap_p4d_range mm/memory.c:1873 [inline] unmap_page_range+0x1f83/0x43a0 mm/memory.c:1894 unmap_single_vma+0x194/0x2b0 mm/memory.c:1940 unmap_vmas+0x22f/0x490 mm/memory.c:1984 exit_mmap+0x1c1/0xba0 mm/mmap.c:1284 __mmput+0x12a/0x410 kernel/fork.c:1356 mmput+0x62/0x70 kernel/fork.c:1378 exit_mm kernel/exit.c:570 [inline] do_exit+0x9ba/0x2d70 kernel/exit.c:925 do_group_exit+0xd3/0x2a0 kernel/exit.c:1087 get_signal+0x24ed/0x26c0 kernel/signal.c:3036 arch_do_signal_or_restart+0x90/0x7e0 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] irqentry_exit_to_user_mode+0x13f/0x280 kernel/entry/common.c:231 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 RIP: 0033:0x7fc3f7e53b33 Code: Unable to access opcode bytes at 0x7fc3f7e53b09. RSP: 002b:00007fff9d7d4640 EFLAGS: 00010246 RAX: 000000002057eff8 RBX: 0000000000000002 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000055557180c3c8 RBP: 00007fff9d7d4758 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 00000000000a7220 R13: 00007fc3f81a5fa0 R14: 0000000000000032 R15: fffffffffffffffe