rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 1-...!: (1 GPs behind) idle=7324/1/0x4000000000000000 softirq=30040/30045 fqs=3 (detected by 0, t=10502 jiffies, g=42561, q=247 ncpus=2) Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 8540 Comm: syz-executor Not tainted 6.1.136-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025 RIP: 0010:rcu_dynticks_curr_cpu_in_eqs include/linux/context_tracking.h:122 [inline] RIP: 0010:rcu_is_watching+0x36/0xa0 kernel/rcu/tree.c:721 Code: e8 3f 33 a4 08 89 c3 83 f8 08 73 60 49 bf 00 00 00 00 00 fc ff df 4c 8d 34 dd 70 09 3d 8c 4c 89 f0 48 c1 e8 03 42 80 3c 38 00 <74> 08 4c 89 f7 e8 10 44 67 00 48 c7 c3 68 57 03 00 49 03 1e 48 89 RSP: 0018:ffffc900001e0d00 EFLAGS: 00000046 RAX: 1ffffffff187a12f RBX: 0000000000000001 RCX: 5db6ea8df7080100 RDX: ffff88802f370000 RSI: ffffffff8abf0d80 RDI: ffffffff8abf0d40 RBP: ffffc900001e0e98 R08: dffffc0000000000 R09: fffffbfff1bfd03e R10: fffffbfff1bfd03e R11: 1ffffffff1bfd03d R12: ffff888078671340 R13: dffffc0000000000 R14: ffffffff8c3d0978 R15: dffffc0000000000 FS: 00005555563f9500(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f1321e4db25 CR3: 000000002f97d000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: trace_hrtimer_expire_entry include/trace/events/timer.h:239 [inline] __run_hrtimer kernel/time/hrtimer.c:1688 [inline] __hrtimer_run_queues+0x49c/0xc80 kernel/time/hrtimer.c:1755 hrtimer_interrupt+0x3bb/0x8d0 kernel/time/hrtimer.c:1817 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1107 [inline] __sysvec_apic_timer_interrupt+0x153/0x5a0 arch/x86/kernel/apic/apic.c:1124 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline] sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1118 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691 RIP: 0010:lock_acquire+0x20f/0x490 kernel/locking/lockdep.c:5666 Code: 00 9c 8f 84 24 80 00 00 00 f6 84 24 81 00 00 00 02 0f 85 f5 00 00 00 41 f7 c6 00 02 00 00 74 01 fb 48 c7 44 24 60 0e 36 e0 45 <4b> c7 44 3d 00 00 00 00 00 66 43 c7 44 3d 09 00 00 43 c6 44 3d 0b RSP: 0018:ffffc90004bafaa0 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 0000000000000000 RCX: 5db6ea8df7080100 RDX: 0000000000000000 RSI: ffffffff8a6c0f80 RDI: ffffffff8abf0da0 RBP: ffffc90004bafba8 R08: dffffc0000000000 R09: fffffbfff2117049 R10: fffffbfff2117049 R11: 1ffffffff2117048 R12: 0000000000000001 R13: 1ffff92000975f60 R14: 0000000000000246 R15: dffffc0000000000 rcu_lock_acquire include/linux/rcupdate.h:350 [inline] rcu_read_lock include/linux/rcupdate.h:791 [inline] percpu_ref_tryget_many include/linux/percpu-refcount.h:241 [inline] percpu_ref_tryget include/linux/percpu-refcount.h:266 [inline] css_tryget include/linux/cgroup.h:357 [inline] get_mem_cgroup_from_objcg include/linux/memcontrol.h:523 [inline] memcg_slab_pre_alloc_hook mm/slab.h:493 [inline] slab_pre_alloc_hook+0x18b/0x310 mm/slab.h:715 slab_alloc_node mm/slub.c:3318 [inline] slab_alloc mm/slub.c:3406 [inline] __kmem_cache_alloc_lru mm/slub.c:3413 [inline] kmem_cache_alloc_lru+0x49/0x2e0 mm/slub.c:3429 alloc_inode_sb include/linux/fs.h:3245 [inline] shmem_alloc_inode+0x24/0x40 mm/shmem.c:3898 alloc_inode fs/inode.c:261 [inline] new_inode_pseudo+0x5f/0x1c0 fs/inode.c:1063 new_inode+0x25/0x1c0 fs/inode.c:1091 shmem_get_inode+0x347/0xbf0 mm/shmem.c:2354 shmem_symlink+0x97/0x670 mm/shmem.c:3150 vfs_symlink+0x247/0x3d0 fs/namei.c:4471 do_symlinkat+0x1ae/0x3f0 fs/namei.c:4500 __do_sys_symlinkat fs/namei.c:4517 [inline] __se_sys_symlinkat fs/namei.c:4514 [inline] __x64_sys_symlinkat+0x95/0xa0 fs/namei.c:4514 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f1321d8dee7 Code: 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 0a 01 00 00 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:00007ffd151d60f8 EFLAGS: 00000202 ORIG_RAX: 000000000000010a RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f1321d8dee7 RDX: 00007f1321e12311 RSI: 00000000ffffff9c RDI: 00007ffd151d6190 RBP: 00007ffd151d613c R08: 0000000000000013 R09: 00007ffd151d5e47 R10: 0000000000000000 R11: 0000000000000202 R12: 00000000000000a9 R13: 0000000000000061 R14: 000000000006aace R15: 00007ffd151d6190 rcu: rcu_preempt kthread starved for 10494 jiffies! g42561 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0 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:27040 pid:16 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5244 [inline] __schedule+0x10e9/0x40d0 kernel/sched/core.c:6561 schedule+0xb9/0x180 kernel/sched/core.c:6637 schedule_timeout+0x15c/0x280 kernel/time/timer.c:1965 rcu_gp_fqs_loop+0x2f2/0x1310 kernel/rcu/tree.c:1706 rcu_gp_kthread+0x95/0x380 kernel/rcu/tree.c:1905 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 rcu: Stack dump where RCU GP kthread last ran: CPU: 0 PID: 8539 Comm: syz.0.1240 Not tainted 6.1.136-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025 RIP: 0010:csd_lock_wait kernel/smp.c:424 [inline] RIP: 0010:smp_call_function_many_cond+0xe7b/0x1270 kernel/smp.c:998 Code: 00 00 00 41 8b 1f 89 de 83 e6 01 31 ff e8 5d e9 0a 00 83 e3 01 48 bb 00 00 00 00 00 fc ff df 75 07 e8 e9 e5 0a 00 eb 37 f3 90 <41> 0f b6 04 1c 84 c0 75 10 41 f7 07 01 00 00 00 74 1e e8 ce e5 0a RSP: 0018:ffffc90004037560 EFLAGS: 00000246 RAX: ffffffff8175ddd2 RBX: dffffc0000000000 RCX: 0000000000080000 RDX: ffffc9000c739000 RSI: 000000000007ffff RDI: 0000000000080000 RBP: ffffc900040376c0 R08: dffffc0000000000 R09: fffffbfff2117049 R10: fffffbfff2117049 R11: 1ffffffff2117048 R12: 1ffff110171e81b9 R13: ffff8880b8e3bb00 R14: 0000000000000001 R15: ffff8880b8f40dc8 FS: 00007fe98988d6c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b2d61cff8 CR3: 000000007f956000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: on_each_cpu_cond_mask+0x3b/0x80 kernel/smp.c:1166 on_each_cpu include/linux/smp.h:71 [inline] text_poke_sync arch/x86/kernel/alternative.c:1334 [inline] text_poke_bp_batch+0x2b0/0x7d0 arch/x86/kernel/alternative.c:1534 text_poke_bp+0xd2/0x150 arch/x86/kernel/alternative.c:1771 __static_call_transform+0x318/0x500 arch/x86/kernel/static_call.c:109 arch_static_call_transform+0xca/0x270 arch/x86/kernel/static_call.c:161 __static_call_update+0xdd/0x5b0 kernel/static_call_inline.c:136 tracepoint_update_call kernel/tracepoint.c:317 [inline] tracepoint_add_func+0x6bf/0x9a0 kernel/tracepoint.c:365 tracepoint_probe_register_prio_may_exist+0x5c/0x90 kernel/tracepoint.c:482 bpf_raw_tp_link_attach+0x3d1/0x550 kernel/bpf/syscall.c:3387 bpf_raw_tracepoint_open+0x194/0x200 kernel/bpf/syscall.c:3414 __sys_bpf+0x4e9/0x6d0 kernel/bpf/syscall.c:5062 __do_sys_bpf kernel/bpf/syscall.c:5124 [inline] __se_sys_bpf kernel/bpf/syscall.c:5122 [inline] __x64_sys_bpf+0x78/0x90 kernel/bpf/syscall.c:5122 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fe98898e969 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:00007fe98988d038 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 00007fe988bb5fa0 RCX: 00007fe98898e969 RDX: 0000000000000010 RSI: 00002000000001c0 RDI: 0000000000000011 RBP: 00007fe988a10ab1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fe988bb5fa0 R15: 00007ffd9ab5e618