rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P21404/1:b..l P42/2:b..l
rcu: (detected by 1, t=10502 jiffies, g=101569, q=1175 ncpus=2)
task:kworker/u8:2 state:R running task stack:21432 pid:42 tgid:42 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:5298 [inline]
__schedule+0x1553/0x5240 kernel/sched/core.c:6911
preempt_schedule_notrace+0x57/0x90 kernel/sched/core.c:7188
preempt_schedule_notrace_thunk+0x16/0x30 arch/x86/entry/thunk.S:13
rcu_read_unlock_sched_notrace include/linux/rcupdate.h:984 [inline]
find_stack lib/stackdepot.c:636 [inline]
stack_depot_save_flags+0x2ff/0x810 lib/stackdepot.c:676
kasan_save_stack mm/kasan/common.c:58 [inline]
kasan_save_track+0x4f/0x80 mm/kasan/common.c:78
poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
__kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:415
kasan_kmalloc include/linux/kasan.h:263 [inline]
__do_kmalloc_node mm/slub.c:5260 [inline]
__kmalloc_noprof+0x3e7/0x7b0 mm/slub.c:5272
kmalloc_noprof include/linux/slab.h:954 [inline]
batadv_tvlv_realloc_packet_buff net/batman-adv/tvlv.c:283 [inline]
batadv_tvlv_container_ogm_append+0x16c/0x520 net/batman-adv/tvlv.c:324
batadv_iv_ogm_schedule_buff net/batman-adv/bat_iv_ogm.c:823 [inline]
batadv_iv_ogm_schedule+0x2b2/0xf60 net/batman-adv/bat_iv_ogm.c:876
batadv_iv_send_outstanding_bat_ogm_packet+0x6c8/0x7e0 net/batman-adv/bat_iv_ogm.c:1712
process_one_work kernel/workqueue.c:3276 [inline]
process_scheduled_works+0xb6e/0x18c0 kernel/workqueue.c:3359
worker_thread+0xa53/0xfc0 kernel/workqueue.c:3440
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
task:syz.5.5434 state:R running task stack:25896 pid:21404 tgid:21395 ppid:19372 task_flags:0x400040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5298 [inline]
__schedule+0x1553/0x5240 kernel/sched/core.c:6911
preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7238
irqentry_exit+0x599/0x620 kernel/entry/common.c:239
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lock_release+0x2d7/0x3d0 kernel/locking/lockdep.c:5893
Code: 7c ae 10 00 00 00 00 eb b5 e8 55 48 83 09 f7 c3 00 02 00 00 74 b9 65 48 8b 05 c5 35 ae 10 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 22 24 cd
RSP: 0018:ffffc90004107640 EFLAGS: 00000282
RAX: 67ecd9f83214d400 RBX: 0000000000000202 RCX: 0000000000000046
RDX: 00000000cbb457a5 RSI: ffffffff8d7c0cea RDI: ffffffff8ba67580
RBP: ffff88802f3dc8e0 R08: ffffffff8b2601d0 R09: ffffffff8ddcb9c0
R10: 0000000000000000 R11: ffffed100bd6e3d5 R12: 0000000000000002
R13: 0000000000000002 R14: ffff88803fcc2298 R15: ffff88802f3dbd00
rt_spin_unlock+0x29/0x200 kernel/locking/spinlock_rt.c:80
spin_unlock_irqrestore include/linux/spinlock_rt.h:129 [inline]
__skb_try_recv_datagram+0xa9/0x1b0 net/core/datagram.c:267
__unix_dgram_recvmsg+0x2e3/0xd60 net/unix/af_unix.c:2573
sock_recvmsg_nosec+0x10c/0x140 net/socket.c:1078
____sys_recvmsg+0x3ef/0x4b0 net/socket.c:2810
___sys_recvmsg+0x215/0x590 net/socket.c:2854
do_recvmmsg+0x33a/0x800 net/socket.c:2949
__sys_recvmmsg net/socket.c:3023 [inline]
__do_sys_recvmmsg net/socket.c:3046 [inline]
__se_sys_recvmmsg net/socket.c:3039 [inline]
__x64_sys_recvmmsg+0x198/0x250 net/socket.c:3039
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f3d6edbc799
RSP: 002b:00007f3d6cff5028 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: ffffffffffffffda RBX: 00007f3d6f036090 RCX: 00007f3d6edbc799
RDX: 0000000000010106 RSI: 00002000000000c0 RDI: 0000000000000004
RBP: 00007f3d6ee52c99 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f3d6f036128 R14: 00007f3d6f036090 R15: 00007ffdc6fc22f8
rcu: rcu_preempt kthread starved for 8854 jiffies! g101569 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:27680 pid:18 tgid:18 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5298 [inline]
__schedule+0x1553/0x5240 kernel/sched/core.c:6911
__schedule_loop kernel/sched/core.c:6993 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7008
schedule_timeout+0x158/0x2c0 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x312/0x11d0 kernel/rcu/tree.c:2095
rcu_gp_kthread+0x9e/0x2b0 kernel/rcu/tree.c:2297
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Tainted: G L syzkaller #0 PREEMPT_{RT,(full)}
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:63
Code: be 5c 02 e9 13 c4 03 00 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 f3 bc 25 00 fb f4 cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90
RSP: 0018:ffffffff8da07dc0 EFLAGS: 00000246
RAX: 0000000000641b1d RBX: ffffffff8199709a RCX: 0000000080000001
RDX: 0000000000000001 RSI: ffffffff8d564872 RDI: ffffffff8ba67580
RBP: ffffffff8da07eb0 R08: ffff8880b8833e1b R09: 1ffff110171067c3
R10: dffffc0000000000 R11: ffffed10171067c4 R12: 0000000000000000
R13: 1ffffffff1b605d8 R14: 0000000000000000 R15: 1ffffffff1b605d8
FS: 0000000000000000(0000) GS:ffff888126336000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000170030 CR3: 00000000668f4000 CR4: 00000000003526f0
Call Trace:
arch_safe_halt arch/x86/kernel/process.c:766 [inline]
default_idle+0x9/0x20 arch/x86/kernel/process.c:767
default_idle_call+0x72/0xb0 kernel/sched/idle.c:122
cpuidle_idle_call kernel/sched/idle.c:199 [inline]
do_idle+0x36a/0x5f0 kernel/sched/idle.c:352
cpu_startup_entry+0x43/0x60 kernel/sched/idle.c:451
rest_init+0x2de/0x300 init/main.c:760
start_kernel+0x385/0x3d0 init/main.c:1210
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