rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P16232/1:b..l (detected by 0, t=10503 jiffies, g=86289, q=23 ncpus=2) task:kworker/u4:31 state:R running task stack:25336 pid:16232 ppid:2 flags:0x00004000 Workqueue: bat_events batadv_nc_worker Call Trace: context_switch kernel/sched/core.c:5244 [inline] __schedule+0x143f/0x4570 kernel/sched/core.c:6561 preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6873 irqentry_exit+0x53/0x80 kernel/entry/common.c:439 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691 RIP: 0010:lock_acquire+0x26f/0x5a0 kernel/locking/lockdep.c:5666 Code: 2b 00 74 08 4c 89 f7 e8 af 54 77 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:ffffc90003297a80 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 1ffff92000652f5c RCX: 1ffff92000652efc RDX: dffffc0000000000 RSI: ffffffff8b0c2f40 RDI: ffffffff8b5f70e0 RBP: ffffc90003297be0 R08: dffffc0000000000 R09: fffffbfff225764d R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff92000652f58 R13: dffffc0000000000 R14: ffffc90003297ae0 R15: 0000000000000246 rcu_lock_acquire include/linux/rcupdate.h:350 [inline] rcu_read_lock include/linux/rcupdate.h:791 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline] batadv_nc_worker+0xe8/0x610 net/batman-adv/network-coding.c:719 process_one_work+0x917/0x1260 kernel/workqueue.c:2292 worker_thread+0xa47/0x1200 kernel/workqueue.c:2439 kthread+0x28d/0x320 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 rcu: rcu_preempt kthread starved for 10529 jiffies! g86289 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:26080 pid:16 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5244 [inline] __schedule+0x143f/0x4570 kernel/sched/core.c:6561 schedule+0xbf/0x180 kernel/sched/core.c:6637 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1965 rcu_gp_fqs_loop+0x2d2/0x1150 kernel/rcu/tree.c:1706 rcu_gp_kthread+0xa3/0x3b0 kernel/rcu/tree.c:1905 kthread+0x28d/0x320 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: Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 17234 Comm: syz.4.3049 Not tainted 6.1.132-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 RIP: 0010:jhash2 include/linux/jhash.h:129 [inline] RIP: 0010:hash_stack lib/stackdepot.c:276 [inline] RIP: 0010:__stack_depot_save+0x80/0x470 lib/stackdepot.c:444 Code: 89 c8 44 8d 2c cd 7b 71 f5 75 83 fe 04 72 6b 44 89 ed 44 89 e8 4c 89 fa 03 02 03 6a 04 44 03 6a 08 44 89 ef c1 c7 04 44 29 e8 <31> c7 41 01 ed 29 fd 89 fb c1 c3 06 31 eb 44 01 ef 89 d9 c1 c1 08 RSP: 0018:ffffc900001e0988 EFLAGS: 00000006 RAX: 000000002a710af6 RBX: 00000000f327adb0 RCX: 00000000c78a00a6 RDX: ffffc900001e09fc RSI: 0000000000000017 RDI: 00000000bd7a7c13 RBP: 0000000037efe9a0 R08: 000000000000000d R09: 0000000000000001 R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000a20 R13: 000000003bd7a7c1 R14: 0000000000000000 R15: ffffc900001e09f0 FS: 00007fa8e89b56c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200000032000 CR3: 0000000053416000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x60/0x70 mm/kasan/common.c:52 __kasan_slab_alloc+0x65/0x70 mm/kasan/common.c:328 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook+0x52/0x3a0 mm/slab.h:737 slab_alloc_node mm/slub.c:3398 [inline] slab_alloc mm/slub.c:3406 [inline] __kmem_cache_alloc_lru mm/slub.c:3413 [inline] kmem_cache_alloc+0x10c/0x2d0 mm/slub.c:3422 __sigqueue_alloc+0x419/0x530 kernel/signal.c:436 __send_signal_locked+0x22f/0xe00 kernel/signal.c:1129 do_send_sig_info kernel/signal.c:1301 [inline] group_send_sig_info+0x28a/0x300 kernel/signal.c:1449 do_bpf_send_signal+0x81/0x150 kernel/trace/bpf_trace.c:839 irq_work_single+0xd5/0x230 kernel/irq_work.c:211 irq_work_run_list kernel/irq_work.c:242 [inline] irq_work_run+0x187/0x350 kernel/irq_work.c:251 __sysvec_irq_work+0xbb/0x360 arch/x86/kernel/irq_work.c:22 instr_sysvec_irq_work arch/x86/kernel/irq_work.c:17 [inline] sysvec_irq_work+0x98/0xc0 arch/x86/kernel/irq_work.c:17 asm_sysvec_irq_work+0x16/0x20 arch/x86/include/asm/idtentry.h:728 RIP: 0010:arch_static_branch arch/x86/include/asm/jump_label.h:27 [inline] RIP: 0010:static_key_false include/linux/jump_label.h:207 [inline] RIP: 0010:native_write_msr arch/x86/include/asm/msr.h:147 [inline] RIP: 0010:wrmsr arch/x86/include/asm/msr.h:254 [inline] RIP: 0010:native_apic_msr_write+0x35/0x50 arch/x86/include/asm/apic.h:206 Code: 74 2a 83 ff 30 74 25 eb 10 81 ff d0 00 00 00 74 1b 81 ff e0 00 00 00 74 13 c1 ef 04 81 c7 00 08 00 00 89 f9 89 f0 31 d2 0f 30 <66> 90 c3 89 f6 31 d2 e9 5f fc 33 03 66 2e 0f 1f 84 00 00 00 00 00 RSP: 0018:ffffc900033b7ca8 EFLAGS: 00000246 RAX: 00000000000000f6 RBX: ffffffff8cdf6b78 RCX: 000000000000083f RDX: 0000000000000000 RSI: 00000000000000f6 RDI: 000000000000083f RBP: 0000000000000000 R08: ffffffff8442f164 R09: fffff52000676f85 R10: 0000000000000000 R11: dffffc0000000001 R12: ffff8880b8f33d90 R13: 1ffff92000676f00 R14: dffffc0000000000 R15: 0000000000000020 arch_irq_work_raise+0x82/0xd0 arch/x86/kernel/irq_work.c:31 irq_work_queue+0xa3/0x150 kernel/irq_work.c:114 bpf_send_signal_common+0x2e6/0x450 kernel/trace/bpf_trace.c:878 ____bpf_send_signal kernel/trace/bpf_trace.c:887 [inline] bpf_send_signal+0x15/0x20 kernel/trace/bpf_trace.c:885 bpf_prog_7ba5217f62dcd359+0x38/0x3c bpf_dispatcher_nop_func include/linux/bpf.h:1000 [inline] __bpf_prog_run include/linux/filter.h:603 [inline] bpf_prog_run include/linux/filter.h:610 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2284 [inline] bpf_trace_run2+0x1fd/0x410 kernel/trace/bpf_trace.c:2323 __bpf_trace_sys_enter+0x60/0x70 include/trace/events/syscalls.h:18 trace_sys_enter include/trace/events/syscalls.h:18 [inline] syscall_trace_enter kernel/entry/common.c:81 [inline] __syscall_enter_from_user_work kernel/entry/common.c:100 [inline] syscall_enter_from_user_mode+0x206/0x230 kernel/entry/common.c:118 do_syscall_64+0x1e/0xb0 arch/x86/entry/common.c:77 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fa8e7b29359 Code: 64 c7 00 16 00 00 00 b8 ff ff ff ff c3 0f 1f 40 00 90 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 c7 c0 0f 00 00 00 0f 05 <0f> 1f 80 00 00 00 00 48 81 ec 48 01 00 00 49 89 d0 64 48 8b 04 25 RSP: 002b:00007fa8e89b4b40 EFLAGS: 00000246 ORIG_RAX: 000000000000000f RAX: ffffffffffffffda RBX: 00007fa8e7da5fa8 RCX: 00007fa8e7b29359 RDX: 00007fa8e89b4b40 RSI: 00007fa8e89b4c70 RDI: 0000000000000011 RBP: 00007fa8e7da5fa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fa8e7da5fac R13: 0000000000000000 R14: 00007fff1551cb40 R15: 00007fff1551cc28