rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 0-...!: (1 ticks this GP) idle=b074/1/0x4000000000000000 softirq=53805/53806 fqs=7 rcu: (detected by 1, t=10502 jiffies, g=41345, q=694 ncpus=2) Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 7091 Comm: syz-executor Not tainted 6.13.0-rc5-syzkaller-00004-gccb98ccef0e5 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:native_save_fl arch/x86/include/asm/irqflags.h:19 [inline] RIP: 0010:arch_local_save_flags arch/x86/include/asm/irqflags.h:87 [inline] RIP: 0010:arch_irqs_disabled arch/x86/include/asm/irqflags.h:147 [inline] RIP: 0010:__raw_spin_lock_irq include/linux/spinlock_api_smp.h:117 [inline] RIP: 0010:_raw_spin_lock_irq+0x75/0x120 kernel/locking/spinlock.c:170 Code: c7 44 24 10 50 6a cb 8b 49 89 e5 49 c1 ed 03 48 b8 f1 f1 f1 f1 00 f3 f3 f3 4b 89 44 3d 00 4c 89 f3 48 c1 eb 03 42 80 3c 3b 00 <74> 08 4c 89 f7 e8 d1 71 3a f6 48 c7 44 24 20 00 00 00 00 9c 8f 44 RSP: 0018:ffffc90000007ca0 EFLAGS: 00000046 RAX: f3f3f300f1f1f1f1 RBX: 1ffff92000000f98 RCX: ffff88802c5d9e00 RDX: 0000000000010000 RSI: ffffffff8c5fb0c0 RDI: ffff8880b862c880 RBP: ffffc90000007d30 R08: ffffffff818cda66 R09: 1ffffffff2032fce R10: dffffc0000000000 R11: fffffbfff2032fcf R12: ffff8880b862c880 R13: 1ffff92000000f94 R14: ffffc90000007cc0 R15: dffffc0000000000 FS: 000055556a8a2500(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000110c436030 CR3: 000000007d132000 CR4: 0000000000350ef0 Call Trace: __run_hrtimer kernel/time/hrtimer.c:1743 [inline] __hrtimer_run_queues+0x670/0xd30 kernel/time/hrtimer.c:1803 hrtimer_interrupt+0x403/0xa40 kernel/time/hrtimer.c:1865 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline] __sysvec_apic_timer_interrupt+0x112/0x420 arch/x86/kernel/apic/apic.c:1055 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1049 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:finish_task_switch+0x1ea/0x870 kernel/sched/core.c:5243 Code: c9 50 e8 49 0c 0c 00 48 83 c4 08 4c 89 f7 e8 ed 39 00 00 0f 1f 44 00 00 4c 89 f7 e8 e0 c9 5c 0a e8 0b 8c 38 00 fb 48 8b 5d c0 <48> 8d bb f8 15 00 00 48 89 f8 48 c1 e8 03 49 be 00 00 00 00 00 fc RSP: 0018:ffffc9000bcdf968 EFLAGS: 00000286 RAX: eead845281727f00 RBX: ffff88802c5d9e00 RCX: ffffffff9a3ab903 RDX: dffffc0000000000 RSI: ffffffff8c0a98e0 RDI: ffffffff8c5fb0e0 RBP: ffffc9000bcdf9b0 R08: ffffffff90197e77 R09: 1ffffffff2032fce R10: dffffc0000000000 R11: fffffbfff2032fcf R12: 1ffff110170c7edc R13: dffffc0000000000 R14: ffff8880b863e8c0 R15: ffff8880b863f6e0 context_switch kernel/sched/core.c:5372 [inline] __schedule+0x1858/0x4c30 kernel/sched/core.c:6756 __schedule_loop kernel/sched/core.c:6833 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6848 do_nanosleep+0x197/0x600 kernel/time/hrtimer.c:2079 hrtimer_nanosleep+0x1ec/0x410 kernel/time/hrtimer.c:2126 __do_sys_clock_nanosleep kernel/time/posix-timers.c:1402 [inline] __se_sys_clock_nanosleep+0x32d/0x3c0 kernel/time/posix-timers.c:1379 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: 0033:0x7ff6415b85e5 Code: 24 0c 89 3c 24 48 89 4c 24 18 e8 f6 54 ff ff 4c 8b 54 24 18 48 8b 54 24 10 41 89 c0 8b 74 24 0c 8b 3c 24 b8 e6 00 00 00 0f 05 <44> 89 c7 48 89 04 24 e8 4f 55 ff ff 48 8b 04 24 48 83 c4 28 f7 d8 RSP: 002b:00007ffdb5225aa0 EFLAGS: 00000293 ORIG_RAX: 00000000000000e6 RAX: ffffffffffffffda RBX: 00000000000001b2 RCX: 00007ff6415b85e5 RDX: 00007ffdb5225ae0 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007ffdb5225b3c R08: 0000000000000000 R09: 7fffffffffffffff R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000032 R13: 000000000007acd9 R14: 00007ffdb5225b90 R15: 0000000000000bb8 rcu: rcu_preempt kthread starved for 10488 jiffies! g41345 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:25976 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0x1850/0x4c30 kernel/sched/core.c:6756 __schedule_loop kernel/sched/core.c:6833 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6848 schedule_timeout+0x15a/0x290 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2045 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2247 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 UID: 0 PID: 11884 Comm: syz.3.1031 Not tainted 6.13.0-rc5-syzkaller-00004-gccb98ccef0e5 #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+0x19f3/0x2c60 kernel/smp.c:884 Code: 45 8b 65 00 44 89 e6 83 e6 01 31 ff e8 56 e9 0b 00 41 83 e4 01 49 bc 00 00 00 00 00 fc ff df 75 07 e8 01 e5 0b 00 eb 38 f3 90 <42> 0f b6 04 23 84 c0 75 11 41 f7 45 00 01 00 00 00 74 1e e8 e5 e4 RSP: 0018:ffffc9000cd7f980 EFLAGS: 00000246 RAX: ffffffff81938efb RBX: 1ffff110170c8c89 RCX: 0000000000080000 RDX: ffffc9000d6c2000 RSI: 000000000007ffff RDI: 0000000000080000 RBP: ffffc9000cd7fb80 R08: ffffffff81938eca R09: 1ffffffff2854910 R10: dffffc0000000000 R11: fffffbfff2854911 R12: dffffc0000000000 R13: ffff8880b8646448 R14: ffff8880b873fac0 R15: 0000000000000000 FS: 00007f66d2c3b6c0(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f66d2c3af98 CR3: 00000000598c8000 CR4: 0000000000350ef0 Call Trace: on_each_cpu_cond_mask+0x3f/0x80 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+0x352/0xb30 arch/x86/kernel/alternative.c:2324 text_poke_flush arch/x86/kernel/alternative.c:2515 [inline] text_poke_finish+0x30/0x50 arch/x86/kernel/alternative.c:2522 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146 static_key_slow_inc_cpuslocked+0x80/0xf0 kernel/jump_label.c:168 static_key_slow_inc+0x1a/0x30 kernel/jump_label.c:191 io_uring_create+0xf2/0xc00 io_uring/io_uring.c:3646 io_uring_setup io_uring/io_uring.c:3811 [inline] __do_sys_io_uring_setup io_uring/io_uring.c:3838 [inline] __se_sys_io_uring_setup+0x2ba/0x330 io_uring/io_uring.c:3832 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: 0033:0x7f66d1d85d29 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:00007f66d2c3afc8 EFLAGS: 00000206 ORIG_RAX: 00000000000001a9 RAX: ffffffffffffffda RBX: 00007f66d1f75fa0 RCX: 00007f66d1d85d29 RDX: 0000000000000000 RSI: 00000000200008c0 RDI: 0000000000000ec5 RBP: 00000000200008c0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000ec5 R15: 0000000000000000