rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 0-...!: (1 GPs behind) idle=70ec/1/0x4000000000000000 softirq=108774/108779 fqs=1
rcu: (detected by 1, t=10502 jiffies, g=118369, q=705 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 24773 Comm: kworker/u8:29 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Workqueue: bat_events batadv_tt_purge
RIP: 0010:check_kcov_mode kernel/kcov.c:183 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x1f/0x70 kernel/kcov.c:217
Code: 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 48 8b 04 24 65 48 8b 0d 88 70 73 11 65 8b 15 a9 70 73 11 81 e2 00 01 ff 00 74 11 <81> fa 00 01 00 00 75 35 83 b9 cc 16 00 00 00 74 2c 8b 91 a8 16 00
RSP: 0018:ffffc90000007d50 EFLAGS: 00000006
RAX: ffffffff8ba47647 RBX: ffff8880b8628418 RCX: ffff88808f629ec0
RDX: 0000000000010000 RSI: ffff8880a4b92300 RDI: ffff8880b8628418
RBP: dffffc0000000000 R08: ffffffff9030b2f7 R09: 1ffffffff206165e
R10: dffffc0000000000 R11: fffffbfff206165f R12: 1ffff110170c5078
R13: ffff8880a4b92300 R14: ffff8880a4b92300 R15: ffff8880b86282c4
FS: 0000000000000000(0000) GS:ffff88812528d000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f64b9c17dac CR3: 0000000064458000 CR4: 00000000003526f0
Call Trace:
timerqueue_linked_add+0x27/0x2e0 lib/timerqueue.c:95
enqueue_hrtimer+0x18e/0x2c0 kernel/time/hrtimer.c:1117
__run_hrtimer kernel/time/hrtimer.c:1946 [inline]
__hrtimer_run_queues+0x4d2/0xa20 kernel/time/hrtimer.c:1994
hrtimer_interrupt+0x44b/0x950 kernel/time/hrtimer.c:2113
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
__sysvec_apic_timer_interrupt+0x102/0x430 arch/x86/kernel/apic/apic.c:1067
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1061 [inline]
sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1061
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:should_resched arch/x86/include/asm/preempt.h:104 [inline]
RIP: 0010:__local_bh_enable_ip+0xd8/0x130 kernel/softirq.c:457
Code: 8b e8 8c e4 20 0a 65 66 8b 05 5c 53 b1 11 66 85 c0 75 32 bf 01 00 00 00 e8 75 fa 0b 00 e8 e0 0d 46 00 fb 65 8b 05 38 53 b1 11 <85> c0 75 05 e8 2f be ab ff 5b 41 5e e9 97 ba 23 0a cc 90 0f 0b 90
RSP: 0018:ffffc90005d8f9b0 EFLAGS: 00000202
RAX: 0000000080000000 RBX: 0000000000000201 RCX: 0000000000000046
RDX: 0000000000000006 RSI: ffffffff8dfa6af6 RDI: ffffffff8c28ade0
RBP: ffff8880597bc198 R08: ffffffff9030b2f7 R09: 1ffffffff206165e
R10: dffffc0000000000 R11: fffffbfff206165f R12: ffff888025bd50c8
R13: dffffc0000000000 R14: ffffffff8b773847 R15: ffff888020761e78
spin_unlock_bh include/linux/spinlock.h:396 [inline]
batadv_tt_local_purge+0x2a7/0x340 net/batman-adv/translation-table.c:1320
batadv_tt_purge+0x35/0x9e0 net/batman-adv/translation-table.c:3514
process_one_work kernel/workqueue.c:3302 [inline]
process_scheduled_works+0xb5d/0x1860 kernel/workqueue.c:3385
worker_thread+0xa53/0xfc0 kernel/workqueue.c:3466
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
rcu: rcu_preempt kthread starved for 10500 jiffies! g118369 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->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:R running task stack:27736 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5388 [inline]
__schedule+0x17b4/0x5680 kernel/sched/core.c:7189
__schedule_loop kernel/sched/core.c:7268 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7283
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+0x514/0xb70 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:
CPU: 1 UID: 0 PID: 25380 Comm: syz.4.5270 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:csd_lock_wait kernel/smp.c:342 [inline]
RIP: 0010:smp_call_function_many_cond+0xfcf/0x13d0 kernel/smp.c:892
Code: 79 45 8b 2e 44 89 ee 83 e6 01 31 ff e8 da 07 0c 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 85 03 0c 00 eb 37 f3 90 <43> 0f b6 04 2c 84 c0 75 10 41 f7 06 01 00 00 00 74 1e e8 6a 03 0c
RSP: 0018:ffffc9000336f440 EFLAGS: 00000293
RAX: ffffffff81b9bc06 RBX: ffff8880b873c148 RCX: ffff88803802bd80
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc9000336f580 R08: ffffffff9030b2f7 R09: 1ffffffff206165e
R10: dffffc0000000000 R11: fffffbfff206165f R12: 1ffff110170c8589
R13: dffffc0000000000 R14: ffff8880b8642c48 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff88812538d000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c2858bb CR3: 000000000e74a000 CR4: 00000000003526f0
Call Trace:
on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1057
__flush_tlb_multi arch/x86/include/asm/paravirt.h:46 [inline]
flush_tlb_multi arch/x86/mm/tlb.c:1361 [inline]
flush_tlb_mm_range+0x5c3/0x10b0 arch/x86/mm/tlb.c:1451
tlb_flush arch/x86/include/asm/tlb.h:23 [inline]
tlb_flush_mmu_tlbonly include/asm-generic/tlb.h:509 [inline]
tlb_flush_mmu+0x1af/0xa30 mm/mmu_gather.c:423
tlb_finish_mmu+0xf9/0x230 mm/mmu_gather.c:549
free_ldt_pgtables+0x19d/0x350 arch/x86/kernel/ldt.c:411
arch_exit_mmap arch/x86/include/asm/mmu_context.h:229 [inline]
exit_mmap+0x1af/0x9e0 mm/mmap.c:1285
__mmput+0x118/0x430 kernel/fork.c:1178
exit_mm+0x18e/0x250 kernel/exit.c:581
do_exit+0x6a2/0x22c0 kernel/exit.c:963
do_group_exit+0x21b/0x2d0 kernel/exit.c:1117
get_signal+0x1284/0x1330 kernel/signal.c:3037
arch_do_signal_or_restart+0xbc/0x830 arch/x86/kernel/signal.c:337
__exit_to_user_mode_loop kernel/entry/common.c:64 [inline]
exit_to_user_mode_loop+0x86/0x480 kernel/entry/common.c:98
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:238 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline]
do_syscall_64+0x33e/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f64b999ce59
Code: Unable to access opcode bytes at 0x7f64b999ce2f.
RSP: 002b:00007f64ba8050e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: 0000000000000001 RBX: 00007f64b9c15fa8 RCX: 00007f64b999ce59
RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007f64b9c15fac
RBP: 00007f64b9c15fa0 R08: 3fffffffffffffff R09: 0000000000000000
R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000
R13: 00007f64b9c16038 R14: 00007ffc71ac6610 R15: 00007ffc71ac66f8