rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 0-...!: (1 GPs behind) idle=faac/1/0x4000000000000000 softirq=44708/44709 fqs=19 rcu: (detected by 1, t=10506 jiffies, g=49201, q=987 ncpus=2) Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 13695 Comm: syz.3.2548 Not tainted 6.12.0-syzkaller-11930-g0e287d31b62b #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:__lock_release kernel/locking/lockdep.c:5535 [inline] RIP: 0010:lock_release+0x285/0x6f0 kernel/locking/lockdep.c:5870 Code: 0f 85 37 04 00 00 8b 55 24 85 d2 0f 85 b4 03 00 00 48 8d 7d 22 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 0f b6 14 02 <48> 89 f8 83 e0 07 83 c0 01 38 d0 7c 08 84 d2 0f 85 08 04 00 00 66 RSP: 0018:ffffc90000007ca8 EFLAGS: 00000806 RAX: dffffc0000000000 RBX: 1ffff92000000f97 RCX: ffffc90000007cf8 RDX: 0000000000000000 RSI: ffff88806042b300 RDI: ffff88801e6b0b2a RBP: ffff88801e6b0b08 R08: 0000000000000000 R09: fffffbfff20bee82 R10: ffffffff905f7417 R11: 0000000000000001 R12: ffff88806042b300 R13: 0000000000000002 R14: ffff88801e6b0ad8 R15: ffff88801e6b0000 FS: 000055555ddc6500(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f6d7814dfd8 CR3: 00000000673f2000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __raw_spin_unlock include/linux/spinlock_api_smp.h:141 [inline] _raw_spin_unlock+0x16/0x50 kernel/locking/spinlock.c:186 spin_unlock include/linux/spinlock.h:391 [inline] advance_sched+0x611/0xc60 net/sched/sch_taprio.c:981 __run_hrtimer kernel/time/hrtimer.c:1739 [inline] __hrtimer_run_queues+0x20a/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:lock_acquire.part.0+0x155/0x380 kernel/locking/lockdep.c:5814 Code: b8 ff ff ff ff 65 0f c1 05 e0 10 97 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:ffffc9001b7ef9b8 EFLAGS: 00000206 RAX: 0000000000000046 RBX: 1ffff920036fdf38 RCX: ffffffff816a828e RDX: 0000000000000001 RSI: ffffffff8b6ce300 RDI: ffffffff8bd1edc0 RBP: 0000000000000200 R08: 0000000000000000 R09: fffffbfff2dcafb9 R10: ffffffff96e57dcf R11: 0000000000000000 R12: 0000000000000000 R13: ffffc90000a45820 R14: 0000000000000000 R15: 0000000000000000 __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] futex_q_lock+0x57/0x70 kernel/futex/core.c:524 futex_wait_setup+0xad/0x290 kernel/futex/waitwake.c:622 __futex_wait+0x267/0x3c0 kernel/futex/waitwake.c:664 futex_wait+0xe9/0x380 kernel/futex/waitwake.c:697 do_futex+0x22b/0x350 kernel/futex/syscalls.c:102 __do_sys_futex kernel/futex/syscalls.c:179 [inline] __se_sys_futex kernel/futex/syscalls.c:160 [inline] __x64_sys_futex+0x1e1/0x4c0 kernel/futex/syscalls.c:160 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: 0033:0x7f6d77380849 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffcaf08c8e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: ffffffffffffffda RBX: 00007ffcaf08ca00 RCX: 00007f6d77380849 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f6d77545fac RBP: 00007f6d77545fac R08: 00007f6d78150000 R09: 00007ffcaf08cbcf R10: 00007ffcaf08c9f0 R11: 0000000000000246 R12: 0000000000081e95 R13: 00007ffcaf08c9f0 R14: 0000000000000032 R15: 0000000000081e63 rcu: rcu_preempt kthread starved for 10410 jiffies! g49201 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:26384 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 rcu: Stack dump where RCU GP kthread last ran: CPU: 1 UID: 0 PID: 13708 Comm: syz.2.2554 Not tainted 6.12.0-syzkaller-11930-g0e287d31b62b #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:csd_lock_wait kernel/smp.c:340 [inline] RIP: 0010:smp_call_function_many_cond+0x458/0x1300 kernel/smp.c:884 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 7a 0d 0c 00 f3 90 <41> 0f b6 04 24 40 38 c5 7c 08 84 c0 0f 85 a7 0c 00 00 8b 43 08 31 RSP: 0018:ffffc9001bbefb18 EFLAGS: 00000246 RAX: 0000000000080000 RBX: ffff8880b86469c0 RCX: ffffc9000bd41000 RDX: 0000000000080000 RSI: ffffffff8182b7a6 RDI: 0000000000000005 RBP: 0000000000000003 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000004 R12: ffffed10170c8d39 R13: 0000000000000001 R14: ffff8880b86469c8 R15: ffff8880b873fe40 FS: 00007f294a86e6c0(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 00000000517d2000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: on_each_cpu_cond_mask+0x40/0x90 kernel/smp.c:1051 on_each_cpu include/linux/smp.h:71 [inline] text_poke_sync arch/x86/kernel/alternative.c:2114 [inline] text_poke_bp_batch+0x22b/0x760 arch/x86/kernel/alternative.c:2324 text_poke_flush arch/x86/kernel/alternative.c:2515 [inline] text_poke_flush arch/x86/kernel/alternative.c:2512 [inline] text_poke_finish+0x30/0x40 arch/x86/kernel/alternative.c:2522 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146 jump_label_update+0x1d7/0x400 kernel/jump_label.c:920 static_key_slow_inc_cpuslocked kernel/jump_label.c:168 [inline] static_key_slow_inc_cpuslocked+0x82/0x120 kernel/jump_label.c:151 static_key_slow_inc+0x1a/0x30 kernel/jump_label.c:191 io_uring_create io_uring/io_uring.c:3616 [inline] io_uring_setup+0x2054/0x3230 io_uring/io_uring.c:3781 __do_sys_io_uring_setup io_uring/io_uring.c:3808 [inline] __se_sys_io_uring_setup io_uring/io_uring.c:3802 [inline] __x64_sys_io_uring_setup+0x98/0x140 io_uring/io_uring.c:3802 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: 0033:0x7f2949980849 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f294a86dfe8 EFLAGS: 00000246 ORIG_RAX: 00000000000001a9 RAX: ffffffffffffffda RBX: 00007f2949b45fa0 RCX: 00007f2949980849 RDX: 0000000000000000 RSI: 00000000200001c0 RDI: 000000000000010f RBP: 00000000200001c0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 000000000000010f R15: 0000000000000000