rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 0-...!: (1 GPs behind) idle=341c/1/0x4000000000000000 softirq=7687/7688 fqs=0 (detected by 1, t=10503 jiffies, g=6841, q=875 ncpus=2) Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 2963 Comm: kworker/0:3 Not tainted 6.1.92-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024 Workqueue: events_power_efficient gc_worker RIP: 0010:__rcu_read_unlock+0x46/0x100 kernel/rcu/tree_plugin.h:423 Code: 4d 8d ae 3c 04 00 00 4c 89 eb 48 c1 eb 03 42 0f b6 04 23 84 c0 75 61 41 8b 6d 00 ff cd 42 0f b6 04 23 84 c0 75 69 41 89 6d 00 <85> ed 75 1d 4d 8d be 40 04 00 00 4c 89 f8 48 c1 e8 03 42 0f b6 04 RSP: 0018:ffffc90000007c88 EFLAGS: 00000046 RAX: 0000000000000000 RBX: 1ffff11005237baf RCX: ffff8880291bd940 RDX: 0000000000010000 RSI: ffffffff8b3d45c0 RDI: ffffffff8b3d4580 RBP: 0000000000000001 R08: ffffffff88b4ebe2 R09: ffffed100ea8842c R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000 R13: ffff8880291bdd7c R14: ffff8880291bd940 R15: 17d5f3a03b170800 FS: 0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b32b27000 CR3: 000000000ce8e000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_read_unlock include/linux/rcupdate.h:823 [inline] advance_sched+0x7f1/0x970 net/sched/sch_taprio.c:755 __run_hrtimer kernel/time/hrtimer.c:1686 [inline] __hrtimer_run_queues+0x5e5/0xe50 kernel/time/hrtimer.c:1750 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1812 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1095 [inline] __sysvec_apic_timer_interrupt+0x156/0x580 arch/x86/kernel/apic/apic.c:1112 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1106 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:653 RIP: 0010:seqcount_lockdep_reader_access+0x1dc/0x220 include/linux/seqlock.h:105 Code: f8 4d 85 ed 75 16 e8 13 86 c6 f8 eb 15 e8 0c 86 c6 f8 e8 d7 00 c7 01 4d 85 ed 74 ea e8 fd 85 c6 f8 fb 48 c7 04 24 0e 36 e0 45 <4b> c7 04 3c 00 00 00 00 66 43 c7 44 3c 09 00 00 43 c6 44 3c 0b 00 RSP: 0018:ffffc9000b57fa40 EFLAGS: 00000293 RAX: ffffffff88c40753 RBX: 0000000000000000 RCX: ffff8880291bd940 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc9000b57faf0 R08: ffffffff88c40729 R09: fffffbfff2093856 R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000 R13: 0000000000000200 R14: 0000000000000046 R15: 1ffff920016aff48 nf_conntrack_get_ht include/net/netfilter/nf_conntrack.h:343 [inline] gc_worker+0x325/0x1530 net/netfilter/nf_conntrack_core.c:1503 process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292 worker_thread+0xa47/0x1200 kernel/workqueue.c:2439 kthread+0x28d/0x320 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 rcu: rcu_preempt kthread timer wakeup didn't happen for 10502 jiffies! g6841 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=1 timer-softirq=2320 rcu: rcu_preempt kthread starved for 10503 jiffies! g6841 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:26680 pid:16 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5245 [inline] __schedule+0x142d/0x4550 kernel/sched/core.c:6558 schedule+0xbf/0x180 kernel/sched/core.c:6634 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1965 rcu_gp_fqs_loop+0x2d2/0x1150 kernel/rcu/tree.c:1706 rcu_gp_kthread+0xa3/0x3b0 kernel/rcu/tree.c:1905 kthread+0x28d/0x320 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 rcu: Stack dump where RCU GP kthread last ran: CPU: 1 PID: 3570 Comm: syz-executor.1 Not tainted 6.1.92-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024 RIP: 0010:csd_lock_wait kernel/smp.c:424 [inline] RIP: 0010:smp_call_function_many_cond+0x1fb0/0x3460 kernel/smp.c:998 Code: 2f 44 89 ee 83 e6 01 31 ff e8 ec 42 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 0a e8 77 3f 0b 00 e9 1b ff ff ff f3 90 <42> 0f b6 04 2b 84 c0 75 14 41 f7 07 01 00 00 00 0f 84 fe fe ff ff RSP: 0018:ffffc9000403f840 EFLAGS: 00000293 RAX: ffffffff817f4dfb RBX: 1ffff1101730859d RCX: ffff888022eabb80 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc9000403fc20 R08: ffffffff817f4dc4 R09: fffffbfff2093858 R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000800000000 R13: dffffc0000000000 R14: 0000000000000000 R15: ffff8880b9842ce8 FS: 0000555556f15480(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f5499ba1bd0 CR3: 0000000061473000 CR4: 00000000003526e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: on_each_cpu_cond_mask+0x3b/0x80 kernel/smp.c:1166 invalidate_bdev+0x8a/0xb0 block/bdev.c:85 ext4_put_super+0x96d/0x10e0 fs/ext4/super.c:1281 generic_shutdown_super+0x130/0x340 fs/super.c:501 kill_block_super+0x7a/0xe0 fs/super.c:1459 deactivate_locked_super+0xa0/0x110 fs/super.c:332 cleanup_mnt+0x490/0x520 fs/namespace.c:1186 task_work_run+0x246/0x300 kernel/task_work.c:179 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop+0xde/0x100 kernel/entry/common.c:177 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline] syscall_exit_to_user_mode+0x60/0x270 kernel/entry/common.c:303 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:87 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f401027e217 Code: b0 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 0f 1f 44 00 00 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 b0 ff ff ff f7 d8 64 89 02 b8 RSP: 002b:00007ffd2c15b188 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007f401027e217 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffd2c15b240 RBP: 00007ffd2c15b240 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffd2c15c2f0 R13: 00007f40102d9636 R14: 00000000000102b2 R15: 0000000000000014