rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 0-....: (1 GPs behind) idle=433/1/0x4000000000000000 softirq=21548/21549 fqs=2099 rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P1343/1:b..l (detected by 1, t=10502 jiffies, g=31793, q=327006) Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 7515 Comm: syz.0.2993 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 RIP: 0010:check_preemption_disabled+0x26/0x110 lib/smp_processor_id.c:16 Code: 7a 8a eb 00 55 41 57 41 56 53 48 83 ec 10 65 48 8b 04 25 28 00 00 00 48 89 44 24 08 65 8b 05 a9 ee 42 76 65 8b 0d 12 49 43 76 c1 ff ff ff 7f 74 1f 65 48 8b 0c 25 28 00 00 00 48 3b 4c 24 08 RSP: 0018:ffffc90005faef78 EFLAGS: 00000086 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000003 RDX: 0000000000000000 RSI: ffffffff8a7a2a20 RDI: ffffffff8a7a29e0 RBP: 0000000000000001 R08: ffffc90005faf197 R09: ffffc90005faf160 R10: dffffc0000000000 R11: fffff52000bf5e33 R12: dffffc0000000000 R13: ffffc90005faf1c6 R14: ffffffff8c125d00 R15: ffffc90005faf380 FS: 0000555593fc7500(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b34663fff CR3: 000000002b99a000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_lockdep_current_cpu_online+0x35/0x130 kernel/rcu/tree.c:1171 rcu_read_lock_held_common kernel/rcu/update.c:112 [inline] rcu_read_lock_held+0x1a/0x40 kernel/rcu/update.c:309 perf_get_guest_cbs include/linux/perf_event.h:1274 [inline] perf_instruction_pointer+0x5a/0x3e0 arch/x86/events/core.c:2951 perf_prepare_sample+0x188/0x1cb0 kernel/events/core.c:7627 __perf_event_output kernel/events/core.c:7802 [inline] perf_event_output_forward+0x185/0x2e0 kernel/events/core.c:7822 __perf_event_overflow+0x35f/0x550 kernel/events/core.c:9515 perf_swevent_overflow kernel/events/core.c:9591 [inline] perf_swevent_event+0x4b8/0x540 kernel/events/core.c:9629 perf_tp_event+0x324/0xbe0 kernel/events/core.c:10047 perf_trace_run_bpf_submit+0xf3/0x1c0 kernel/events/core.c:10021 perf_trace_preemptirq_template+0x2aa/0x360 include/trace/events/preemptirq.h:14 trace_irq_enable_rcuidle+0x108/0x180 include/trace/events/preemptirq.h:40 trace_hardirqs_on+0x57/0x80 kernel/trace/trace_preemptirq.c:44 asm_sysvec_irq_work+0x16/0x20 arch/x86/include/asm/idtentry.h:713 RIP: 0010:rcu_read_unlock_special+0x7f/0x4a0 kernel/rcu/tree_plugin.h:674 Code: eb 03 48 b8 f1 f1 f1 f1 f8 f2 f2 f2 4a 89 04 2b 42 c7 44 2b 08 f8 f3 f3 f3 65 44 8b 35 c2 22 9d 7e 41 f7 c6 00 00 f0 00 74 40 <48> c7 44 24 20 0e 36 e0 45 4a c7 04 2b 00 00 00 00 42 c7 44 2b 08 RSP: 0018:ffffc90005faf7a0 EFLAGS: 00000206 RAX: 27ee484418801400 RBX: 1ffff92000bf5ef8 RCX: 27ee484418801400 RDX: dffffc0000000000 RSI: ffffffff8a2b2be0 RDI: ffffffff8a7a2a40 RBP: ffffc90005faf880 R08: ffff8880b903b30b R09: 1ffff11017207661 R10: dffffc0000000000 R11: ffffed1017207662 R12: ffffffff8c323400 R13: dffffc0000000000 R14: 0000000000000246 R15: 0000000000000001 __rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:422 rcu_read_unlock include/linux/rcupdate.h:772 [inline] mod_objcg_mlstate+0x23b/0x2e0 mm/memcontrol.c:832 drain_obj_stock+0x1e5/0x360 mm/memcontrol.c:3203 refill_obj_stock+0x11d/0x470 mm/memcontrol.c:3242 obj_cgroup_charge+0x1c3/0x320 mm/memcontrol.c:3301 memcg_slab_pre_alloc_hook mm/slab.h:287 [inline] slab_pre_alloc_hook+0x9d/0xc0 mm/slab.h:497 slab_alloc_node mm/slub.c:3139 [inline] slab_alloc mm/slub.c:3233 [inline] kmem_cache_alloc+0x3d/0x280 mm/slub.c:3238 __d_alloc+0x27/0x6d0 fs/dcache.c:1749 d_alloc_pseudo+0x19/0x70 fs/dcache.c:1880 alloc_file_pseudo+0xe0/0x200 fs/file_table.c:256 __anon_inode_getfile fs/anon_inodes.c:109 [inline] anon_inode_getfile+0xc1/0x1a0 fs/anon_inodes.c:147 __do_sys_perf_event_open kernel/events/core.c:12613 [inline] __se_sys_perf_event_open+0xc02/0x1bb0 kernel/events/core.c:12387 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7fc3d323ae59 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fffedfc74b8 EFLAGS: 00000246 ORIG_RAX: 000000000000012a RAX: ffffffffffffffda RBX: 00007fc3d34c2fa0 RCX: 00007fc3d323ae59 RDX: 0000000000000000 RSI: ffffffffffffffff RDI: 00002000000003c0 RBP: 00007fc3d32d0e6f R08: 0000000000000000 R09: 0000000000000000 R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000 R13: 00007fc3d34c2fac R14: 00007fc3d34c2fa0 R15: 00007fc3d34c2fa0 task:kworker/0:3 state:R running task stack:24416 pid: 1343 ppid: 2 flags:0x00004000 Workqueue: events_power_efficient gc_worker Call Trace: context_switch kernel/sched/core.c:5049 [inline] __schedule+0x11c3/0x4350 kernel/sched/core.c:6395 preempt_schedule_irq+0xbb/0x160 kernel/sched/core.c:6799 irqentry_exit+0x63/0x70 kernel/entry/common.c:432 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676 RIP: 0010:seqcount_lockdep_reader_access+0x196/0x1d0 include/linux/seqlock.h:106 Code: f9 4d 85 e4 75 16 e8 e9 e4 51 f9 eb 15 e8 e2 e4 51 f9 e8 bd 08 98 01 4d 85 e4 74 ea e8 d3 e4 51 f9 fb 48 c7 04 24 0e 36 e0 45 <4b> c7 04 3e 00 00 00 00 43 c7 44 3e 08 00 00 00 00 65 48 8b 04 25 RSP: 0018:ffffc900050a7a20 EFLAGS: 00000293 RAX: ffffffff88270dcd RBX: 0000000000000000 RCX: ffff888022af1dc0 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc900050a7ad0 R08: ffffffff901e915f R09: 1ffffffff203d22b R10: dffffc0000000000 R11: fffffbfff203d22c R12: 0000000000000200 R13: dffffc0000000000 R14: 1ffff92000a14f44 R15: dffffc0000000000 nf_conntrack_get_ht include/net/netfilter/nf_conntrack.h:338 [inline] gc_worker+0x2e5/0x13d0 net/netfilter/nf_conntrack_core.c:1472 process_one_work+0x867/0xff0 kernel/workqueue.c:2310 worker_thread+0xad7/0x12a0 kernel/workqueue.c:2457 kthread+0x42e/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287