rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 1-...!: (1 ticks this GP) idle=dd8c/1/0x4000000000000000 softirq=42521/42521 fqs=2
rcu: (detected by 0, t=10502 jiffies, g=33837, q=311 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 9851 Comm: syz.1.1291 Not tainted 6.16.0-rc2-syzkaller-00231-g75f5f23f8787 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:lock_acquire+0x10a/0x360 kernel/locking/lockdep.c:5871
Code: 99 8d e8 69 50 c8 09 65 ff 05 e2 fd fe 10 45 31 c9 4c 89 7c 24 08 41 f7 c7 00 02 00 00 41 0f 94 c1 4c 89 ef 89 de 8b 54 24 04 <44> 89 e1 45 89 f0 6a 00 6a 00 6a 00 55 ff 74 24 30 e8 e0 02 00 00
RSP: 0018:ffffc90000a08b40 EFLAGS: 00000046
RAX: 0000000000000001 RBX: 0000000000000000 RCX: 6853ac0f9467aa00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff99c9e3d0
RBP: ffffffff84c7a30b R08: 0000000000000001 R09: 0000000000000001
R10: dffffc0000000000 R11: fffff52000141196 R12: 0000000000000000
R13: ffffffff99c9e3d0 R14: 0000000000000001 R15: 0000000000000046
FS: 00007f7c3e88b6c0(0000) GS:ffff888125d51000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005555643f3588 CR3: 00000000652cb000 CR4: 0000000000350ef0
Call Trace:
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0xa7/0xf0 kernel/locking/spinlock.c:162
debug_object_activate+0xbb/0x420 lib/debugobjects.c:818
debug_hrtimer_activate kernel/time/hrtimer.c:445 [inline]
debug_activate kernel/time/hrtimer.c:484 [inline]
enqueue_hrtimer+0x30/0x3a0 kernel/time/hrtimer.c:1088
__run_hrtimer kernel/time/hrtimer.c:1778 [inline]
__hrtimer_run_queues+0x656/0xc60 kernel/time/hrtimer.c:1825
hrtimer_interrupt+0x45b/0xaa0 kernel/time/hrtimer.c:1887
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1039 [inline]
__sysvec_apic_timer_interrupt+0x10b/0x410 arch/x86/kernel/apic/apic.c:1056
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1050
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:__genradix_ptr_inlined include/linux/generic-radix-tree.h:201 [inline]
RIP: 0010:__genradix_ptr+0x1da/0x220 lib/generic-radix-tree.c:14
Code: 75 14 e8 09 d5 fe fc 45 31 f6 eb 28 e8 ff d4 fe fc 40 84 ed 74 ec bf 01 02 00 00 48 89 de e8 cd d9 fe fc 48 81 fb 00 02 00 00 <77> 25 e8 df d4 fe fc 49 01 de 4c 89 f0 5b 41 5c 41 5d 41 5e 41 5f
RSP: 0018:ffffc90005157538 EFLAGS: 00000283
RAX: ffffffff84c18763 RBX: 00000000000001c8 RCX: ffff88802f390000
RDX: 0000000000000002 RSI: 00000000000001c8 RDI: 0000000000000201
RBP: 0000000000000001 R08: ffff88802f390000 R09: 0000000000000042
R10: 0000000000000041 R11: ffffffff8aaecff0 R12: 0000000000000007
R13: dffffc0000000000 R14: ffff888044885c00 R15: 0000000000000009
sctp_stream_out include/net/sctp/structs.h:1490 [inline]
sctp_stream_free_ext+0x5b/0x130 net/sctp/stream.c:59
sctp_stream_free+0x8f/0x110 net/sctp/stream.c:190
sctp_association_free+0x26d/0x7f0 net/sctp/associola.c:351
sctp_cmd_delete_tcb net/sctp/sm_sideeffect.c:950 [inline]
sctp_cmd_interpreter net/sctp/sm_sideeffect.c:1336 [inline]
sctp_side_effects net/sctp/sm_sideeffect.c:1204 [inline]
sctp_do_sm+0x3eba/0x5a20 net/sctp/sm_sideeffect.c:1175
sctp_primitive_SHUTDOWN+0x98/0xc0 net/sctp/primitive.c:89
sctp_close+0x409/0x900 net/sctp/socket.c:1529
inet_release+0x187/0x210 net/ipv4/af_inet.c:435
__sock_release net/socket.c:647 [inline]
sock_close+0xc3/0x240 net/socket.c:1391
__fput+0x44c/0xa70 fs/file_table.c:465
task_work_run+0x1d4/0x260 kernel/task_work.c:227
get_signal+0x11ed/0x1340 kernel/signal.c:2807
arch_do_signal_or_restart+0x9a/0x750 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop+0x75/0x110 kernel/entry/common.c:111
exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline]
do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7c3d98e929
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:00007f7c3e88b038 EFLAGS: 00000246 ORIG_RAX: 0000000000000037
RAX: fffffffffffffe00 RBX: 00007f7c3dbb5fa0 RCX: 00007f7c3d98e929
RDX: 000000000000006f RSI: 0000000000000084 RDI: 0000000000000003
RBP: 00007f7c3da10b39 R08: 0000200000000140 R09: 0000000000000000
R10: 0000200000000200 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f7c3dbb5fa0 R15: 00007ffd1934d548
rcu: rcu_preempt kthread starved for 10498 jiffies! g33837 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:27128 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5396 [inline]
__schedule+0x16f5/0x4d00 kernel/sched/core.c:6785
__schedule_loop kernel/sched/core.c:6863 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6878
schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2054
rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2256
kthread+0x711/0x8a0 kernel/kthread.c:464
ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 UID: 0 PID: 36 Comm: kworker/u8:2 Not tainted 6.16.0-rc2-syzkaller-00231-g75f5f23f8787 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:csd_lock_wait kernel/smp.c:340 [inline]
RIP: 0010:smp_call_function_many_cond+0xf6e/0x12d0 kernel/smp.c:885
Code: 89 ee 83 e6 01 31 ff e8 70 78 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 1b 74 0b 00 eb 37 f3 90 43 0f b6 04 2c <84> c0 75 10 41 f7 07 01 00 00 00 74 1e e8 00 74 0b 00 eb e5 44 89
RSP: 0018:ffffc90000ac76a0 EFLAGS: 00000293
RAX: 0000000000000000 RBX: ffff8880b863b1c0 RCX: ffff8881404b1e00
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90000ac7800 R08: ffffffff8fa10ff7 R09: 1ffffffff1f421fe
R10: dffffc0000000000 R11: fffffbfff1f421ff R12: 1ffff110170e7f5d
R13: dffffc0000000000 R14: 0000000000000001 R15: ffff8880b873fae8
FS: 0000000000000000(0000) GS:ffff888125c51000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2fa1eff8 CR3: 000000000df38000 CR4: 0000000000350ef0
Call Trace:
on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1052
on_each_cpu include/linux/smp.h:71 [inline]
smp_text_poke_sync_each_cpu arch/x86/kernel/alternative.c:2691 [inline]
smp_text_poke_batch_finish+0x5e0/0x1100 arch/x86/kernel/alternative.c:2901
arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146
static_key_enable_cpuslocked+0x128/0x250 kernel/jump_label.c:210
static_key_enable+0x1a/0x20 kernel/jump_label.c:223
toggle_allocation_gate+0xad/0x240 mm/kfence/core.c:850
process_one_work kernel/workqueue.c:3238 [inline]
process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3321
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402
kthread+0x711/0x8a0 kernel/kthread.c:464
ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245