rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 1-...!: (0 ticks this GP) idle=fd24/1/0x4000000000000000 softirq=18983/18983 fqs=0 rcu: (detected by 0, t=10502 jiffies, g=11153, q=1555 ncpus=2) Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 6596 Comm: syz.1.192 Not tainted 6.15.0-rc7-syzkaller-00144-gb1427432d3b6 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:debug_object_deactivate+0x130/0x3a0 lib/debugobjects.c:873 Code: 48 c1 e8 0c 48 0f af c2 48 c1 e8 32 48 8d 1c c0 48 c1 e3 03 48 8d 93 08 dd cb 9a 4c 8d a3 00 dd cb 9a 48 89 d7 48 89 54 24 08 9b 32 99 06 48 8b 54 24 08 48 89 c1 4c 89 e0 48 c1 e8 03 42 80 RSP: 0018:ffffc90000a08d50 EFLAGS: 00000002 RAX: 0000000000002ac5 RBX: 00000000000c0768 RCX: ffffffff81a87845 RDX: ffffffff9ad7e470 RSI: ffffffff8b8fde80 RDI: ffffffff9ad7e470 RBP: ffffc90000a08e30 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: ffffffff9ad7e470 R12: ffffffff9ad7e468 R13: dffffc0000000000 R14: ffff888021773340 R15: 1ffff920001411ac FS: 00007f95a75b16c0(0000) GS:ffff888124ada000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 0000000030108000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: debug_hrtimer_deactivate kernel/time/hrtimer.c:450 [inline] debug_deactivate kernel/time/hrtimer.c:490 [inline] __run_hrtimer kernel/time/hrtimer.c:1729 [inline] __hrtimer_run_queues+0x46f/0xad0 kernel/time/hrtimer.c:1825 hrtimer_interrupt+0x397/0x8e0 kernel/time/hrtimer.c:1887 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline] __sysvec_apic_timer_interrupt+0x108/0x3f0 arch/x86/kernel/apic/apic.c:1055 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0x9f/0xc0 arch/x86/kernel/apic/apic.c:1049 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:lock_acquire+0x62/0x350 kernel/locking/lockdep.c:5870 Code: 39 0c 12 83 f8 07 0f 87 bc 02 00 00 89 c0 48 0f a3 05 52 09 ed 0e 0f 82 74 02 00 00 8b 35 ea 38 ed 0e 85 f6 0f 85 8d 00 00 00 <48> 8b 44 24 30 65 48 2b 05 29 39 0c 12 0f 85 c7 02 00 00 48 83 c4 RSP: 0018:ffffc90004367290 EFLAGS: 00000206 RAX: 0000000000000046 RBX: ffffffff8e3bfc00 RCX: 000000005f967c08 RDX: 0000000000000000 RSI: ffffffff8dbbee43 RDI: ffffffff8bf4a520 RBP: 0000000000000002 R08: 369ab264c5b9844a R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 rcu_lock_acquire include/linux/rcupdate.h:331 [inline] rcu_read_lock include/linux/rcupdate.h:841 [inline] class_rcu_constructor include/linux/rcupdate.h:1155 [inline] unwind_next_frame+0xd1/0x20a0 arch/x86/kernel/unwind_orc.c:479 arch_stack_walk+0x94/0x100 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 unpoison_slab_object mm/kasan/common.c:319 [inline] __kasan_slab_alloc+0x89/0x90 mm/kasan/common.c:345 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4147 [inline] slab_alloc_node mm/slub.c:4196 [inline] kmem_cache_alloc_noprof+0x1cb/0x3b0 mm/slub.c:4203 sctp_chunkify+0x51/0x2d0 net/sctp/sm_make_chunk.c:1381 _sctp_make_chunk+0x148/0x270 net/sctp/sm_make_chunk.c:1454 sctp_make_control+0x2f/0x2d0 net/sctp/sm_make_chunk.c:1490 sctp_make_heartbeat+0xa7/0x2e0 net/sctp/sm_make_chunk.c:1169 sctp_sf_heartbeat net/sctp/sm_statefuns.c:1024 [inline] sctp_sf_do_prm_requestheartbeat+0x27/0x220 net/sctp/sm_statefuns.c:5501 sctp_do_sm+0x17e/0x5c80 net/sctp/sm_sideeffect.c:1166 sctp_primitive_REQUESTHEARTBEAT+0x9f/0xd0 net/sctp/primitive.c:185 sctp_apply_peer_addr_params+0x113/0x3400 net/sctp/socket.c:2438 sctp_setsockopt_peer_addr_params net/sctp/socket.c:2688 [inline] sctp_setsockopt+0x143b/0xb870 net/sctp/socket.c:4639 do_sock_setsockopt+0x221/0x470 net/socket.c:2296 __sys_setsockopt+0x1a0/0x230 net/socket.c:2321 __do_sys_setsockopt net/socket.c:2327 [inline] __se_sys_setsockopt net/socket.c:2324 [inline] __x64_sys_setsockopt+0xbd/0x160 net/socket.c:2324 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x260 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f95a678e969 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:00007f95a75b1038 EFLAGS: 00000246 ORIG_RAX: 0000000000000036 RAX: ffffffffffffffda RBX: 00007f95a69b6080 RCX: 00007f95a678e969 RDX: 0000000000000009 RSI: 0000000000000084 RDI: 0000000000000006 RBP: 00007f95a6810ab1 R08: 000000000000009c R09: 0000000000000000 R10: 0000200000000300 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f95a69b6080 R15: 00007ffcaf10d0b8 rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g11153 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=1 timer-softirq=5093 rcu: rcu_preempt kthread starved for 10502 jiffies! g11153 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:28360 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x116f/0x5de0 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:6860 schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x1ea/0xb00 kernel/rcu/tree.c:2046 rcu_gp_kthread+0x270/0x380 kernel/rcu/tree.c:2248 kthread+0x3c2/0x780 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245