rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P3562/1:b..l P13279/3:b..l P1885/1:b..l
rcu: (detected by 0, t=10503 jiffies, g=75709, q=771 ncpus=2)
task:kworker/u8:7 state:R running task stack:20680 pid:1885 tgid:1885 ppid:2 task_flags:0x4208060 flags:0x00080000
Workqueue: iou_exit io_ring_exit_work
Call Trace:
context_switch kernel/sched/core.c:5258 [inline]
__schedule+0x14ed/0x5040 kernel/sched/core.c:6866
preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7193
irqentry_exit+0x5e3/0x670 kernel/entry/common.c:216
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:memset_orig+0x75/0xb0 arch/x86/lib/memset_64.S:92
Code: 89 47 30 48 89 47 38 48 8d 7f 40 75 d8 0f 1f 84 00 00 00 00 00 89 d1 83 e1 38 74 14 c1 e9 03 66 0f 1f 44 00 00 ff c9 48 89 07 <48> 8d 7f 08 75 f5 83 e2 07 74 0a ff ca 88 07 48 8d 7f 01 75 f6 4c
RSP: 0018:ffffc900050ff330 EFLAGS: 00000202
RAX: 0000000000000000 RBX: ffffc900050ff440 RCX: 0000000000000001
RDX: 0000000000000010 RSI: 0000000000000000 RDI: ffffc900050ff458
RBP: dffffc0000000000 R08: ffffc900050ff467 R09: 0000000000000000
R10: ffffc900050ff458 R11: fffff52000a1fe8d R12: ffffc900050ff458
R13: 1ffff92000a1fe83 R14: ffffc900050ff408 R15: ffffc900050ff450
unwind_next_frame+0xeae/0x23d0 arch/x86/kernel/unwind_orc.c:607
arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:57 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:584
poison_slab_object mm/kasan/common.c:253 [inline]
__kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285
kasan_slab_free include/linux/kasan.h:235 [inline]
slab_free_hook mm/slub.c:2540 [inline]
slab_free mm/slub.c:6674 [inline]
kfree+0x1c0/0x660 mm/slub.c:6882
io_remove_buffers_legacy+0x232/0x310 io_uring/kbuf.c:422
io_put_bl io_uring/kbuf.c:433 [inline]
io_destroy_buffers+0x187/0x2c0 io_uring/kbuf.c:452
io_ring_ctx_free+0xa9/0x530 io_uring/io_uring.c:2842
io_ring_exit_work+0x8d1/0x940 io_uring/io_uring.c:3070
process_one_work+0x93a/0x15a0 kernel/workqueue.c:3279
process_scheduled_works kernel/workqueue.c:3362 [inline]
worker_thread+0x9b0/0xee0 kernel/workqueue.c:3443
kthread+0x389/0x480 kernel/kthread.c:467
ret_from_fork+0x510/0xa50 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
task:syz.1.1584 state:R running task stack:27712 pid:13279 tgid:13279 ppid:12005 task_flags:0x400040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5258 [inline]
__schedule+0x14ed/0x5040 kernel/sched/core.c:6866
preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:7050
preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
__raw_spin_unlock include/linux/spinlock_api_smp.h:143 [inline]
_raw_spin_unlock+0x3f/0x50 kernel/locking/spinlock.c:186
spin_unlock include/linux/spinlock.h:391 [inline]
filemap_map_pages+0x192d/0x1fd0 mm/filemap.c:3931
do_fault_around mm/memory.c:5695 [inline]
do_read_fault mm/memory.c:5728 [inline]
do_fault mm/memory.c:5871 [inline]
do_pte_missing+0x20b0/0x3330 mm/memory.c:4416
handle_pte_fault mm/memory.c:6255 [inline]
__handle_mm_fault mm/memory.c:6393 [inline]
handle_mm_fault+0x1b26/0x32b0 mm/memory.c:6562
do_user_addr_fault+0xa7c/0x1380 arch/x86/mm/fault.c:1336
handle_page_fault arch/x86/mm/fault.c:1476 [inline]
exc_page_fault+0x71/0xd0 arch/x86/mm/fault.c:1532
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618
RIP: 0033:0x7f3bc246f2ed
RSP: 002b:00007ffd040a1850 EFLAGS: 00010202
RAX: 000000110c270000 RBX: 00007f3bc3315720 RCX: 0000000000000002
RDX: 00000000000010d2 RSI: 00000000000000c3 RDI: 0000000000000004
RBP: ffffffff821030d2 R08: 00007f3bc27e6038 R09: 00007f3bc27d2000
R10: 00007f3bc1fff008 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: ffffffff821030b3 R15: 0000000000001c2b
task:kworker/u8:13 state:R running task stack:21472 pid:3562 tgid:3562 ppid:2 task_flags:0x4208060 flags:0x00080000
Workqueue: bat_events batadv_iv_send_outstanding_bat_ogm_packet
Call Trace:
context_switch kernel/sched/core.c:5258 [inline]
__schedule+0x14ed/0x5040 kernel/sched/core.c:6866
preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7193
irqentry_exit+0x5e3/0x670 kernel/entry/common.c:216
asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:lock_release+0x2d8/0x3b0 kernel/locking/lockdep.c:5893
Code: 5c 03 11 00 00 00 00 eb b5 e8 24 99 be 09 f7 c3 00 02 00 00 74 b9 65 48 8b 05 44 17 03 11 48 3b 44 24 28 75 44 fb 48 83 c4 30 <5b> 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc cc 48 8d 3d c1 5c 07
RSP: 0018:ffffc9000c6af908 EFLAGS: 00000282
RAX: 6be1ef23cf4fa200 RBX: 0000000000000202 RCX: 0000000000000046
RDX: 0000000000000003 RSI: ffffffff8db80e95 RDI: ffffffff8be082e0
RBP: ffff88803249a9c0 R08: ffffffff8b25b140 R09: ffffffff8e13f2a0
R10: dffffc0000000000 R11: ffffed1005173317 R12: 0000000000000003
R13: 0000000000000003 R14: ffffffff8e13f2a0 R15: ffff888032499e40
rcu_lock_release include/linux/rcupdate.h:312 [inline]
rcu_read_unlock include/linux/rcupdate.h:868 [inline]
batadv_iv_ogm_slide_own_bcast_window net/batman-adv/bat_iv_ogm.c:778 [inline]
batadv_iv_ogm_schedule_buff net/batman-adv/bat_iv_ogm.c:833 [inline]
batadv_iv_ogm_schedule+0x715/0xf00 net/batman-adv/bat_iv_ogm.c:873
batadv_iv_send_outstanding_bat_ogm_packet+0x6c6/0x7e0 net/batman-adv/bat_iv_ogm.c:1709
process_one_work+0x93a/0x15a0 kernel/workqueue.c:3279
process_scheduled_works kernel/workqueue.c:3362 [inline]
worker_thread+0x9b0/0xee0 kernel/workqueue.c:3443
kthread+0x389/0x480 kernel/kthread.c:467
ret_from_fork+0x510/0xa50 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
rcu: rcu_preempt kthread starved for 10391 jiffies! g75709 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:27832 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5258 [inline]
__schedule+0x14ed/0x5040 kernel/sched/core.c:6866
__schedule_loop kernel/sched/core.c:6948 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6963
schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x301/0x11b0 kernel/rcu/tree.c:2095
rcu_gp_kthread+0x9b/0x2d0 kernel/rcu/tree.c:2297
kthread+0x389/0x480 kernel/kthread.c:467
ret_from_fork+0x510/0xa50 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:82
Code: cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 43 8e 2b 00 f3 0f 1e fa fb f4 cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffffff8de07dc0 EFLAGS: 000002c2
RAX: 00000000017cfe63 RBX: ffffffff819717be RCX: 0000000080000001
RDX: 0000000000000001 RSI: ffffffff8d99cce1 RDI: ffffffff8be082e0
RBP: ffffffff8de07eb0 R08: ffff8880b863375b R09: 1ffff110170c66eb
R10: dffffc0000000000 R11: ffffed10170c66ec R12: ffffffff8fa23d70
R13: 1ffffffff1bd29b8 R14: 0000000000000000 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff888125c0c000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000000200 CR3: 00000000662d8000 CR4: 00000000003526f0
Call Trace:
arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline]
default_idle+0x13/0x20 arch/x86/kernel/process.c:767
default_idle_call+0x73/0xb0 kernel/sched/idle.c:122
cpuidle_idle_call kernel/sched/idle.c:191 [inline]
do_idle+0x1be/0x4d0 kernel/sched/idle.c:332
cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:430
rest_init+0x2de/0x300 init/main.c:757
start_kernel+0x381/0x3d0 init/main.c:1206
x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310
x86_64_start_kernel+0x143/0x1c0 arch/x86/kernel/head64.c:291
common_startup_64+0x13e/0x147