rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P16398/1:b..l P14713/1:b..l
rcu: (detected by 1, t=10503 jiffies, g=83845, q=231 ncpus=2)
task:kworker/u4:0 state:R running task stack:22728 pid:14713 ppid:2 flags:0x00004000
Workqueue: bat_events batadv_nc_worker
Call Trace:
context_switch kernel/sched/core.c:5380 [inline]
__schedule+0x14d2/0x44d0 kernel/sched/core.c:6699
preempt_schedule_irq+0xb5/0x140 kernel/sched/core.c:7009
irqentry_exit+0x67/0x70 kernel/entry/common.c:438
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
RIP: 0010:debug_lockdep_rcu_enabled+0x29/0x30 kernel/rcu/update.c:320
Code: cc f3 0f 1e fa 31 c0 83 3d 3f 91 dc 03 00 74 1d 83 3d b6 c4 dc 03 00 74 14 65 48 8b 0d d0 ba 95 75 31 c0 83 b9 dc 0a 00 00 00 <0f> 94 c0 c3 cc cc cc 66 0f 1f 00 48 8b 3c 24 e8 43 fb ff ff 66 90
RSP: 0018:ffffc900032a7b58 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 0000000000000001 RCX: ffff8880221bbc00
RDX: 0000000000000000 RSI: ffffffff8afc7020 RDI: ffffffff8afc6fe0
RBP: fffffffffffffe38 R08: dffffc0000000000 R09: 1ffffffff21b4aa0
R10: dffffc0000000000 R11: fffffbfff21b4aa1 R12: dffffc0000000000
R13: ffffffff8a3651e2 R14: ffff888060130c80 R15: 000000000000019b
rcu_read_unlock include/linux/rcupdate.h:815 [inline]
batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:412 [inline]
batadv_nc_worker+0x1f4/0x610 net/batman-adv/network-coding.c:719
process_one_work kernel/workqueue.c:2634 [inline]
process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711
worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792
kthread+0x2fa/0x390 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
task:syz.1.3149 state:R running task stack:27016 pid:16398 ppid:9393 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5380 [inline]
__schedule+0x14d2/0x44d0 kernel/sched/core.c:6699
preempt_schedule_common+0x82/0xc0 kernel/sched/core.c:6866
preempt_schedule+0xab/0xc0 kernel/sched/core.c:6890
preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk_64.S:45
__raw_spin_unlock include/linux/spinlock_api_smp.h:143 [inline]
_raw_spin_unlock+0x3a/0x40 kernel/locking/spinlock.c:186
spin_unlock include/linux/spinlock.h:391 [inline]
zap_pte_range mm/memory.c:1522 [inline]
zap_pmd_range mm/memory.c:1570 [inline]
zap_pud_range mm/memory.c:1599 [inline]
zap_p4d_range mm/memory.c:1620 [inline]
unmap_page_range+0x236f/0x2fe0 mm/memory.c:1641
unmap_vmas+0x25e/0x3a0 mm/memory.c:1731
exit_mmap+0x200/0xb50 mm/mmap.c:3302
__mmput+0x118/0x3c0 kernel/fork.c:1355
exit_mm+0x1da/0x2c0 kernel/exit.c:569
do_exit+0x88e/0x23c0 kernel/exit.c:870
do_group_exit+0x21b/0x2d0 kernel/exit.c:1024
__do_sys_exit_group kernel/exit.c:1035 [inline]
__se_sys_exit_group kernel/exit.c:1033 [inline]
__x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1033
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fc67658ebe9
RSP: 002b:00007ffd21903618 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fc67658ebe9
RDX: 0000000000000064 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007ffd2190367c R08: 000000072190370f R09: 00000000000927c0
R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000000235
R13: 00000000000927c0 R14: 00000000000f298e R15: 00007ffd219036d0
rcu: rcu_preempt kthread starved for 10553 jiffies! g83845 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:27032 pid:17 ppid:2 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5380 [inline]
__schedule+0x14d2/0x44d0 kernel/sched/core.c:6699
schedule+0xbd/0x170 kernel/sched/core.c:6773
schedule_timeout+0x160/0x280 kernel/time/timer.c:2167
rcu_gp_fqs_loop+0x302/0x1560 kernel/rcu/tree.c:1667
rcu_gp_kthread+0x99/0x380 kernel/rcu/tree.c:1866
kthread+0x2fa/0x390 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 16396 Comm: syz.2.3148 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:__lock_acquire+0xd51/0x7c80 kernel/locking/lockdep.c:5107
Code: 47 5d 00 00 41 8b 07 a9 00 00 18 00 0f 84 bb 03 00 00 4c 89 ef 4c 89 f6 ba 08 00 00 00 e8 77 a9 00 00 85 c0 0f 84 53 0e 00 00 <48> c7 c0 80 c4 ea 96 48 c1 e8 03 49 b8 00 00 00 00 00 fc ff df 42
RSP: 0018:ffffc90003257520 EFLAGS: 00000002
RAX: 0000000000000001 RBX: ffff88802b6164c0 RCX: ffffffff8167bce4
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff90da5530
RBP: ffffc90003257768 R08: ffffffff90da5537 R09: 1ffffffff21b4aa6
R10: dffffc0000000000 R11: fffffbfff21b4aa7 R12: 0000000000000000
R13: ffff88802b615a00 R14: ffff88802b6164e0 R15: ffff88802b616500
FS: 00007fac4dea96c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c3617cd CR3: 000000002d590000 CR4: 00000000003506f0
Call Trace:
lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754
__might_fault+0xc6/0x120 mm/memory.c:5946
__clear_user arch/x86/include/asm/uaccess_64.h:167 [inline]
copy_fpstate_to_sigframe+0x13c/0xbe0 arch/x86/kernel/fpu/signal.c:216
get_sigframe+0x5ce/0x7c0 arch/x86/kernel/signal.c:142
x64_setup_rt_frame+0x158/0xcd0 arch/x86/kernel/signal_64.c:175
setup_rt_frame arch/x86/kernel/signal.c:223 [inline]
handle_signal arch/x86/kernel/signal.c:267 [inline]
arch_do_signal_or_restart+0x3e5/0x780 arch/x86/kernel/signal.c:312
exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174
exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210
__syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302
do_syscall_64+0x61/0xb0 arch/x86/entry/common.c:87
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fac4cf8ebe9
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:00007fac4dea90e8 EFLAGS: 00000246
RAX: fffffffffffffffc RBX: 00007fac4d1c6098 RCX: 00007fac4cf8ebe9
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007fac4d1c6098
RBP: 00007fac4d1c6090 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fac4d1c6128 R14: 00007ffe7751acc0 R15: 00007ffe7751ada8