rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P7069/1:b..l (detected by 1, t=10502 jiffies, g=32289, q=61) task:syz-executor.2 state:R running task stack:25016 pid: 7069 ppid: 5820 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5030 [inline] __schedule+0x12c4/0x45b0 kernel/sched/core.c:6376 preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6780 irqentry_exit+0x53/0x80 kernel/entry/common.c:432 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:lock_acquire+0x252/0x4f0 kernel/locking/lockdep.c:5627 Code: 2b 00 74 08 4c 89 f7 e8 ac 73 67 00 f6 44 24 61 02 0f 85 84 01 00 00 41 f7 c7 00 02 00 00 74 01 fb 48 c7 44 24 40 0e 36 e0 45 <4b> c7 44 25 00 00 00 00 00 43 c7 44 25 09 00 00 00 00 43 c7 44 25 RSP: 0018:ffffc900037a7480 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 1ffff920006f4e9c RCX: 1ffff920006f4e3c RDX: dffffc0000000000 RSI: ffffffff8a8b3c20 RDI: ffffffff8ad8f380 RBP: ffffc900037a75e0 R08: dffffc0000000000 R09: fffffbfff1f7ec19 R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff920006f4e98 R13: dffffc0000000000 R14: ffffc900037a74e0 R15: 0000000000000246 rcu_lock_acquire+0x20/0x30 include/linux/rcupdate.h:312 rcu_read_lock include/linux/rcupdate.h:739 [inline] percpu_ref_get_many+0x15/0x110 include/linux/percpu-refcount.h:202 percpu_ref_get include/linux/percpu-refcount.h:222 [inline] css_get include/linux/cgroup.h:325 [inline] charge_memcg+0x145/0x340 mm/memcontrol.c:6746 __mem_cgroup_charge+0x23/0x80 mm/memcontrol.c:6778 mem_cgroup_charge include/linux/memcontrol.h:700 [inline] shmem_add_to_page_cache+0xc22/0x17c0 mm/shmem.c:718 shmem_getpage_gfp+0x1aa1/0x3190 mm/shmem.c:1940 shmem_getpage mm/shmem.c:151 [inline] shmem_write_begin+0xce/0x1a0 mm/shmem.c:2477 generic_perform_write+0x2bf/0x5b0 mm/filemap.c:3785 __generic_file_write_iter+0x243/0x4f0 mm/filemap.c:3912 generic_file_write_iter+0xa7/0x1b0 mm/filemap.c:3944 call_write_iter include/linux/fs.h:2172 [inline] new_sync_write fs/read_write.c:507 [inline] vfs_write+0xacf/0xe50 fs/read_write.c:594 ksys_write+0x1a2/0x2c0 fs/read_write.c:647 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f40fc5c2bef RSP: 002b:00007f40fab35e80 EFLAGS: 00000293 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000001000000 RCX: 00007f40fc5c2bef RDX: 0000000001000000 RSI: 00007f40f2716000 RDI: 0000000000000003 RBP: 0000000000000000 R08: 0000000000000000 R09: 00000000000060f9 R10: 000000000000077c R11: 0000000000000293 R12: 0000000000000003 R13: 00007f40fab35f80 R14: 00007f40fab35f40 R15: 00007f40f2716000 rcu: rcu_preempt kthread starved for 10541 jiffies! g32289 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:27000 pid: 15 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5030 [inline] __schedule+0x12c4/0x45b0 kernel/sched/core.c:6376 schedule+0x11b/0x1f0 kernel/sched/core.c:6459 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1914 rcu_gp_fqs_loop+0x2bf/0x1080 kernel/rcu/tree.c:1972 rcu_gp_kthread+0xa4/0x360 kernel/rcu/tree.c:2145 kthread+0x3f6/0x4f0 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:300 rcu: Stack dump where RCU GP kthread last ran: NMI backtrace for cpu 1 CPU: 1 PID: 7084 Comm: syz-executor.0 Not tainted 5.15.156-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106 nmi_cpu_backtrace+0x46a/0x4a0 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x181/0x2a0 lib/nmi_backtrace.c:62 trigger_single_cpu_backtrace include/linux/nmi.h:166 [inline] rcu_check_gp_kthread_starvation+0x1d2/0x240 kernel/rcu/tree_stall.h:487 print_other_cpu_stall+0x137a/0x14d0 kernel/rcu/tree_stall.h:592 check_cpu_stall kernel/rcu/tree_stall.h:745 [inline] rcu_pending kernel/rcu/tree.c:3932 [inline] rcu_sched_clock_irq+0xa38/0x1150 kernel/rcu/tree.c:2619 update_process_times+0x196/0x200 kernel/time/timer.c:1818 tick_sched_handle kernel/time/tick-sched.c:254 [inline] tick_sched_timer+0x386/0x550 kernel/time/tick-sched.c:1473 __run_hrtimer kernel/time/hrtimer.c:1686 [inline] __hrtimer_run_queues+0x55b/0xcf0 kernel/time/hrtimer.c:1750 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1812 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1085 [inline] __sysvec_apic_timer_interrupt+0x139/0x470 arch/x86/kernel/apic/apic.c:1102 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1096 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:169 [inline] RIP: 0010:_raw_spin_unlock_irq+0x25/0x40 kernel/locking/spinlock.c:202 Code: 91 80 f6 ff 90 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 be b4 3b f7 48 89 df e8 96 08 3d f7 e8 b1 bf 5f f7 fb bf 01 00 00 00 b6 44 30 f7 65 8b 05 87 52 db 75 85 c0 74 02 5b c3 e8 f4 70 d9 RSP: 0018:ffffc90003cb7bc0 EFLAGS: 00000282 RAX: 7d60eef478005600 RBX: ffff8880792fae40 RCX: ffffffff913edf03 RDX: dffffc0000000000 RSI: ffffffff8a8b2980 RDI: 0000000000000001 RBP: 0000000000000000 R08: ffffffff8186dd10 R09: ffffed100f25f5c9 R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000021 R13: dffffc0000000000 R14: ffff8880792fb2d8 R15: ffff8880792fae40 spin_unlock_irq include/linux/spinlock.h:413 [inline] get_signal+0x13ee/0x14e0 kernel/signal.c:2892 arch_do_signal_or_restart+0xc3/0x1890 arch/x86/kernel/signal.c:867 handle_signal_work kernel/entry/common.c:154 [inline] exit_to_user_mode_loop+0x97/0x130 kernel/entry/common.c:178 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:214 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline] syscall_exit_to_user_mode+0x5d/0x240 kernel/entry/common.c:307 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f82fd88a9a4 Code: 0f 82 b9 00 00 00 48 39 f2 72 6e 41 0f 11 0c 24 48 8b 77 f8 48 89 f8 48 89 eb eb 12 66 2e 0f 1f 84 00 00 00 00 00 48 8b 4b 08 <48> 83 c3 08 48 39 d1 72 f3 48 83 e8 08 48 39 f2 73 17 66 2e 0f 1f RSP: 002b:00007fffe4d21970 EFLAGS: 00000287 RAX: 00007f82fd1cd8c0 RBX: 00007f82fd1876a8 RCX: ffffffff8186dd2b RDX: ffffffff8186e165 RSI: ffffffff81a722f7 RDI: 00007f82fd24e000 RBP: 00007f82fd145598 R08: 00007f82fd1c9ac8 R09: 0000000000000473 R10: 00000000816f9850 R11: 000000000000a17c R12: 00007f82fd145590 R13: 0000000000000020 R14: 00007f82fd9f1000 R15: 00007f82fd9fd0e8