rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P6652/1:b..l P5107/1:b..l P6654/1:b..l P4543/1:b..l rcu: (detected by 1, t=10502 jiffies, g=20461, q=291 ncpus=2) task:udevd state:R running task stack:22048 pid:4543 tgid:4543 ppid:1 flags:0x00000002 Call Trace: context_switch kernel/sched/core.c:5408 [inline] __schedule+0x17e8/0x4a20 kernel/sched/core.c:6745 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:7067 irqentry_exit+0x5e/0x90 kernel/entry/common.c:354 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:srso_alias_safe_ret+0x5/0x7 arch/x86/lib/retpoline.S:174 Code: cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc 48 8d 64 24 08 cc e8 f4 ff ff ff 0f 0b cc cc cc cc cc cc cc cc cc cc cc cc cc RSP: 0018:ffffc90009177930 EFLAGS: 00000293 RAX: ffffffff820f9b6b RBX: 0000000000000081 RCX: ffff88807e019e00 RDX: 0000000000000000 RSI: ffff88801e9282b0 RDI: ffffffff8e47d420 RBP: ffff88801e9282b0 R08: ffffffff820fa121 R09: ffffffff821106ca R10: 0000000000000002 R11: ffff88807e019e00 R12: ffff88801e9282b0 R13: ffffffff8e47d420 R14: 0000000000000081 R15: dffffc0000000000 generic_permission+0x2b/0x550 fs/namei.c:401 do_inode_permission fs/namei.c:468 [inline] inode_permission+0xa6/0x460 fs/namei.c:528 may_lookup fs/namei.c:1718 [inline] link_path_walk+0x289/0xea0 fs/namei.c:2273 path_lookupat+0xa9/0x450 fs/namei.c:2492 filename_lookup+0x256/0x610 fs/namei.c:2522 user_path_at_empty+0x42/0x60 fs/namei.c:2929 do_readlinkat+0x118/0x3b0 fs/stat.c:499 __do_sys_readlink fs/stat.c:532 [inline] __se_sys_readlink fs/stat.c:529 [inline] __x64_sys_readlink+0x7f/0x90 fs/stat.c:529 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: 0033:0x7f3212717d47 RSP: 002b:00007ffe526cb598 EFLAGS: 00000206 ORIG_RAX: 0000000000000059 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f3212717d47 RDX: 0000000000000400 RSI: 00007ffe526cb9a8 RDI: 00007ffe526cb5a8 RBP: 00007ffe526cbde8 R08: 00005629bd4fb1fd R09: 0000000000000000 R10: 0000000000000010 R11: 0000000000000206 R12: 0000000000000200 R13: 00007ffe526cb9a8 R14: 00007ffe526cb5a8 R15: 0000000000000000 task:syz.3.262 state:R running task stack:26592 pid:6654 tgid:6654 ppid:6651 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5408 [inline] __schedule+0x17e8/0x4a20 kernel/sched/core.c:6745 preempt_schedule_common+0x84/0xd0 kernel/sched/core.c:6924 preempt_schedule+0xe1/0xf0 kernel/sched/core.c:6948 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] zap_pte_range mm/memory.c:1676 [inline] zap_pmd_range mm/memory.c:1724 [inline] zap_pud_range mm/memory.c:1753 [inline] zap_p4d_range mm/memory.c:1774 [inline] unmap_page_range+0x3631/0x40f0 mm/memory.c:1795 unmap_vmas+0x3cc/0x5f0 mm/memory.c:1885 exit_mmap+0x264/0xc80 mm/mmap.c:3341 __mmput+0x115/0x3c0 kernel/fork.c:1346 exit_mm+0x220/0x310 kernel/exit.c:565 do_exit+0x9aa/0x27e0 kernel/exit.c:861 __do_sys_exit kernel/exit.c:990 [inline] __se_sys_exit kernel/exit.c:988 [inline] __x64_sys_exit+0x40/0x40 kernel/exit.c:988 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: 0033:0x7fb3b2775bd9 RSP: 002b:00007fb3b358bf18 EFLAGS: 00000246 ORIG_RAX: 000000000000003c RAX: ffffffffffffffda RBX: 0000000000000058 RCX: 00007fb3b2775bd9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007fb3b27e4aa1 R08: 0000000000000058 R09: 0000000000000058 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000006e R14: 00007fb3b2904038 R15: 00007ffc25da68f8 task:kworker/0:4 state:R running task stack:21592 pid:5107 tgid:5107 ppid:2 flags:0x00004000 Workqueue: events_power_efficient gc_worker Call Trace: context_switch kernel/sched/core.c:5408 [inline] __schedule+0x17e8/0x4a20 kernel/sched/core.c:6745 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:7067 irqentry_exit+0x5e/0x90 kernel/entry/common.c:354 asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:707 RIP: 0010:seqcount_lockdep_reader_access+0x1e0/0x220 include/linux/seqlock.h:75 Code: f7 4d 85 ed 75 16 e8 ef 31 f6 f7 eb 15 e8 e8 31 f6 f7 e8 43 f1 e5 01 4d 85 ed 74 ea e8 d9 31 f6 f7 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:ffffc90002f8f9a0 EFLAGS: 00000293 RAX: ffffffff899ff577 RBX: 0000000000000000 RCX: ffff888063515a00 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc90002f8fa50 R08: ffffffff899ff54d R09: 1ffffffff25f4ec1 R10: dffffc0000000000 R11: fffffbfff25f4ec2 R12: dffffc0000000000 R13: 0000000000000200 R14: 0000000000000046 R15: 1ffff920005f1f34 nf_conntrack_get_ht include/net/netfilter/nf_conntrack.h:345 [inline] gc_worker+0x316/0x1530 net/netfilter/nf_conntrack_core.c:1488 process_one_work kernel/workqueue.c:3248 [inline] process_scheduled_works+0xa2e/0x1830 kernel/workqueue.c:3329 worker_thread+0x86d/0xd50 kernel/workqueue.c:3409 kthread+0x2f2/0x390 kernel/kthread.c:389 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 task:syz.5.263 state:R running task stack:25360 pid:6652 tgid:6641 ppid:5415 flags:0x00000000 Call Trace: context_switch kernel/sched/core.c:5408 [inline] __schedule+0x17e8/0x4a20 kernel/sched/core.c:6745 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:7067 irqentry_exit+0x5e/0x90 kernel/entry/common.c:354 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:native_save_fl arch/x86/include/asm/irqflags.h:32 [inline] RIP: 0010:arch_local_save_flags arch/x86/include/asm/irqflags.h:67 [inline] RIP: 0010:arch_local_irq_save arch/x86/include/asm/irqflags.h:103 [inline] RIP: 0010:lock_release+0x16d/0x9f0 kernel/locking/lockdep.c:5770 Code: eb 03 42 80 3c 3b 00 74 08 4c 89 f7 e8 bc 4e 89 00 4c 89 6c 24 50 48 c7 84 24 b0 00 00 00 00 00 00 00 9c 8f 84 24 b0 00 00 00 <42> 80 3c 3b 00 74 08 4c 89 f7 e8 a4 4d 89 00 48 8b 9c 24 b0 00 00 RSP: 0000:ffffc90004affca0 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 1ffff9200095ffaa RCX: ffffffff81728e40 RDX: 0000000000000000 RSI: ffffffff8c1fe920 RDI: ffffffff8c1fe8e0 RBP: ffffc90004affdd0 R08: ffffffff8fad4daf R09: 1ffffffff1f5a9b5 R10: dffffc0000000000 R11: fffffbfff1f5a9b6 R12: 1ffff9200095ffa0 R13: ffffffff81e3ab4a R14: ffffc90004affd50 R15: dffffc0000000000 lock_vma_under_rcu+0x58d/0x6e0 do_user_addr_fault arch/x86/mm/fault.c:1329 [inline] handle_page_fault arch/x86/mm/fault.c:1481 [inline] exc_page_fault+0x17b/0x8c0 arch/x86/mm/fault.c:1539 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 RIP: 0033:0x7f847e83b500 RSP: 002b:00007f847f7ec4b0 EFLAGS: 00010282 RAX: 00000000001b2000 RBX: 00007f847f7ec550 RCX: 0000000000000016 RDX: 000000000000007f RSI: 0000000000000200 RDI: 00007f847f7ec5f0 RBP: 00000000000000e8 R08: 00007f8474600000 R09: 00000000000000fe R10: 0000000000000000 R11: 00007f847f7ec560 R12: 0000000000000181 R13: 00007f847e9f5fa0 R14: 0000000000000011 R15: 00007f847f7ec5f0 rcu: rcu_preempt kthread starved for 10413 jiffies! g20461 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:24912 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5408 [inline] __schedule+0x17e8/0x4a20 kernel/sched/core.c:6745 __schedule_loop kernel/sched/core.c:6822 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6837 schedule_timeout+0x1be/0x310 kernel/time/timer.c:2581 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2000 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2202 kthread+0x2f2/0x390 kernel/kthread.c:389 ret_from_fork+0x4d/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: 0 Comm: swapper/1 Not tainted 6.10.0-rc6-syzkaller-00069-g795c58e4c7fc #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024 RIP: 0010:native_irq_disable arch/x86/include/asm/irqflags.h:37 [inline] RIP: 0010:arch_local_irq_disable arch/x86/include/asm/irqflags.h:72 [inline] RIP: 0010:acpi_safe_halt+0x21/0x30 drivers/acpi/processor_idle.c:113 Code: 90 90 90 90 90 90 90 90 90 65 48 8b 04 25 c0 d4 03 00 48 f7 00 08 00 00 00 75 10 eb 07 0f 00 2d b5 5a a3 00 f3 0f 1e fa fb f4 e9 f4 23 2a 00 66 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 RSP: 0018:ffffc900001a7d08 EFLAGS: 00000246 RAX: ffff8880176e0000 RBX: ffff88801be9b864 RCX: 0000000000c08a91 RDX: 0000000000000001 RSI: ffff88801be9b800 RDI: ffff88801be9b864 RBP: 000000000003a578 R08: ffff8880b9537ccb R09: 1ffff110172a6f99 R10: dffffc0000000000 R11: ffffffff8b8618c0 R12: ffff888019bf7000 R13: 0000000000000000 R14: 0000000000000001 R15: ffffffff8eacdca0 FS: 0000000000000000(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fbbb49fb690 CR3: 000000001ec48000 CR4: 0000000000350ef0 Call Trace: acpi_idle_enter+0xe4/0x140 drivers/acpi/processor_idle.c:707 cpuidle_enter_state+0x114/0x480 drivers/cpuidle/cpuidle.c:267 cpuidle_enter+0x5d/0xa0 drivers/cpuidle/cpuidle.c:388 call_cpuidle kernel/sched/idle.c:155 [inline] cpuidle_idle_call kernel/sched/idle.c:236 [inline] do_idle+0x375/0x5d0 kernel/sched/idle.c:332 cpu_startup_entry+0x42/0x60 kernel/sched/idle.c:430 start_secondary+0x100/0x100 arch/x86/kernel/smpboot.c:313 common_startup_64+0x13e/0x147