rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 1-...!: (0 ticks this GP) idle=4f44/1/0x4000000000000000 softirq=54661/54661 fqs=0 rcu: (detected by 0, t=10502 jiffies, g=51737, q=453 ncpus=2) Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 13753 Comm: syz.7.2072 Not tainted 6.13.0-rc5-syzkaller-00006-g56e6a3499e14 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:match_held_lock+0x65/0xc0 kernel/locking/lockdep.c:5326 Code: 20 e5 96 48 c1 f8 03 48 0f af c2 0f b7 53 20 5b 81 e2 ff 1f 00 00 48 39 d0 0f 94 c0 0f b6 c0 c3 cc cc cc cc b8 01 00 00 00 5b cc cc cc cc 31 f6 e8 2f fe ff ff 48 85 c0 75 a7 31 c0 5b c3 cc RSP: 0018:ffffc90000a18be0 EFLAGS: 00000046 RAX: 0000000000000001 RBX: ffff88802d300b30 RCX: ffffc90000a18c70 RDX: 0000000000000003 RSI: ffffffff9aa375e8 RDI: ffff88802d300b30 RBP: 0000000000000003 R08: 0000000000000000 R09: fffffbfff20be6da R10: ffffffff905f36d7 R11: 0000000000000002 R12: ffffffff9aa375e8 R13: ffffffff9aa375e8 R14: ffffc90000a18c70 R15: 0000000000000002 FS: 00007fdbc63fc6c0(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fdbc63fbf98 CR3: 000000008731a000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: find_held_lock+0x2d/0x110 kernel/locking/lockdep.c:5339 __lock_release kernel/locking/lockdep.c:5524 [inline] lock_release+0x227/0x6f0 kernel/locking/lockdep.c:5870 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:149 [inline] _raw_spin_unlock_irqrestore+0x1a/0x80 kernel/locking/spinlock.c:194 debug_object_activate+0x2e6/0x4a0 lib/debugobjects.c:836 debug_hrtimer_activate kernel/time/hrtimer.c:428 [inline] debug_activate kernel/time/hrtimer.c:469 [inline] enqueue_hrtimer+0x25/0x3c0 kernel/time/hrtimer.c:1076 __run_hrtimer kernel/time/hrtimer.c:1756 [inline] __hrtimer_run_queues+0x903/0xae0 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:memcmp+0x6/0x1d0 lib/string.c:667 Code: ca d6 f6 e9 3c ff ff ff 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 41 56 <41> 55 49 bd 00 00 00 00 00 fc ff df 41 54 49 89 d4 55 48 89 f5 53 RSP: 0018:ffffc900040978a8 EFLAGS: 00000246 RAX: 1ffff1100721f8c8 RBX: ffffffff8b814318 RCX: ffffc9000c359000 RDX: 0000000000000006 RSI: ffffffff8b8129e0 RDI: ffff8880390fc650 RBP: 0000000000000006 R08: 0000000000000004 R09: 0000000000000006 R10: 0000000000000006 R11: 0000000000000001 R12: dffffc0000000000 R13: ffff8880390fc5e0 R14: 0000000000000006 R15: 0000000000000007 memcmp include/linux/fortify-string.h:727 [inline] proc_pident_lookup+0x124/0x2a0 fs/proc/base.c:2732 lookup_open.isra.0+0x92d/0x14c0 fs/namei.c:3627 open_last_lookups fs/namei.c:3748 [inline] path_openat+0x904/0x2d60 fs/namei.c:3984 do_filp_open+0x20c/0x470 fs/namei.c:4014 do_sys_openat2+0x17a/0x1e0 fs/open.c:1402 do_sys_open fs/open.c:1417 [inline] __do_sys_openat fs/open.c:1433 [inline] __se_sys_openat fs/open.c:1428 [inline] __x64_sys_openat+0x175/0x210 fs/open.c:1428 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: 0033:0x7fdbc5584690 Code: 48 89 44 24 20 75 93 44 89 54 24 0c e8 49 94 02 00 44 8b 54 24 0c 89 da 48 89 ee 41 89 c0 bf 9c ff ff ff b8 01 01 00 00 0f 05 <48> 3d 00 f0 ff ff 77 38 44 89 c7 89 44 24 0c e8 9c 94 02 00 8b 44 RSP: 002b:00007fdbc63fbf10 EFLAGS: 00000293 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fdbc5584690 RDX: 0000000000000000 RSI: 00007fdbc63fbfa0 RDI: 00000000ffffff9c RBP: 00007fdbc63fbfa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fdbc5776080 R15: 00007ffcf5bce3a8 rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g51737 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=1 timer-softirq=50727 rcu: rcu_preempt kthread starved for 10502 jiffies! g51737 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:27744 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