rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 0-...!: (371 ticks this GP) idle=e554/1/0x4000000000000000 softirq=16707/16710 fqs=0
rcu: (t=10639 jiffies g=10509 q=1356 ncpus=2)
rcu: rcu_preempt kthread timer wakeup didn't happen for 10638 jiffies! g10509 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: Possible timer handling issue on cpu=1 timer-softirq=4500
rcu: rcu_preempt kthread starved for 10639 jiffies! g10509 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:28440 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x1139/0x6150 kernel/sched/core.c:6863
__schedule_loop kernel/sched/core.c:6945 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:6960
schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x1ea/0xaf0 kernel/rcu/tree.c:2083
rcu_gp_kthread+0x26d/0x380 kernel/rcu/tree.c:2285
kthread+0x3c5/0x780 kernel/kthread.c:463
ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
</TASK>
CPU: 0 UID: 0 PID: 5960 Comm: udevd Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:csd_lock_wait kernel/smp.c:342 [inline]
RIP: 0010:smp_call_function_many_cond+0xdfd/0x15e0 kernel/smp.c:877
Code: 57 48 8b 54 24 10 4c 89 74 24 10 49 89 d5 48 89 d5 48 89 54 24 18 49 c1 ed 03 83 e5 07 4d 01 e5 83 c5 03 e8 45 5f 0c 00 f3 90 <41> 0f b6 45 00 40 38 c5 7c 08 84 c0 0f 85 b6 05 00 00 8b 43 08 31
RSP: 0000:ffffc900047af8a8 EFLAGS: 00000293
RAX: 0000000000000000 RBX: ffff8880b8540cc0 RCX: ffffffff81b29cb1
RDX: ffff888026ea4980 RSI: ffffffff81b29c8b RDI: 0000000000000005
RBP: 0000000000000003 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: ffff888026ea54b0 R12: dffffc0000000000
R13: ffffed10170a8199 R14: 0000000000000001 R15: 0000000000000001
FS: 00007ff6007be880(0000) GS:ffff8881248f2000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000561428647fe8 CR3: 000000005cb71000 CR4: 00000000003526f0
Call Trace:
<TASK>
on_each_cpu_cond_mask+0x40/0x90 kernel/smp.c:1043
__flush_tlb_multi arch/x86/include/asm/paravirt.h:91 [inline]
flush_tlb_multi arch/x86/mm/tlb.c:1382 [inline]
flush_tlb_mm_range+0x2f0/0x12c0 arch/x86/mm/tlb.c:1472
flush_tlb_page arch/x86/include/asm/tlbflush.h:324 [inline]
ptep_clear_flush+0x136/0x180 mm/pgtable-generic.c:103
wp_page_copy mm/memory.c:3785 [inline]
do_wp_page+0x171f/0x5010 mm/memory.c:4180
handle_pte_fault mm/memory.c:6289 [inline]
__handle_mm_fault+0x1bd2/0x2bb0 mm/memory.c:6411
handle_mm_fault+0x3fe/0xad0 mm/memory.c:6580
do_user_addr_fault+0x60c/0x1370 arch/x86/mm/fault.c:1336
handle_page_fault arch/x86/mm/fault.c:1476 [inline]
exc_page_fault+0x64/0xc0 arch/x86/mm/fault.c:1532
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618
RIP: 0033:0x7ff6000b5db7
Code: 00 00 00 41 55 48 89 d0 49 89 fd 41 54 49 89 f4 53 4c 89 c3 48 83 ec 10 48 39 4f 60 0f 84 c1 00 00 00 42 f6 44 01 08 01 74 59 <48> 83 61 08 fe 48 3d ff 03 00 00 76 69 49 8b 55 70 49 8d 75 60 48
RSP: 002b:00007ffe7015e0f0 EFLAGS: 00010202
RAX: 0000000000006010 RBX: 00000000000001f0 RCX: 0000561428647fe0
RDX: 0000000000006010 RSI: 0000561428641fd0 RDI: 00007ff6001f1ac0
RBP: 00007ff6001f1ac0 R08: 00000000000001f0 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000561428641fd0
R13: 00007ff6001f1ac0 R14: 00000000000001f0 R15: 00007ff6001f1ac0
</TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 36 Comm: kworker/u8:2 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Workqueue: bat_events batadv_dat_purge
RIP: 0010:trace_hrtimer_expire_exit include/trace/events/timer.h:306 [inline]
RIP: 0010:__run_hrtimer kernel/time/hrtimer.c:1780 [inline]
RIP: 0010:__hrtimer_run_queues+0x9cb/0xc40 kernel/time/hrtimer.c:1841
Code: 1a 14 00 48 8d 3d 65 7f e1 0e 67 48 0f b9 3a e9 23 fb ff ff e8 76 1a 14 00 e8 51 41 f8 ff 31 ff 41 89 c5 89 c6 e8 a5 14 14 00 <45> 84 ed 0f 85 db f8 ff ff e8 57 1a 14 00 48 8d 3d 40 7f e1 0e 67
RSP: 0018:ffffc90000a08e40 EFLAGS: 00000046
RAX: 0000000000010201 RBX: ffff8880b85285c0 RCX: ffffffff81aae16b
RDX: ffff8881422f24c0 RSI: 0000000000000000 RDI: 0000000000000001
RBP: 0000000000000002 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: ffff8881422f2ff0 R12: ffff8880b8528440
R13: 0000000000000001 R14: ffff888078888300 R15: 0000000000000001
FS: 0000000000000000(0000) GS:ffff8881249f2000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000056142864dbe0 CR3: 000000000e184000 CR4: 00000000003526f0
Call Trace:
<IRQ>
hrtimer_interrupt+0x397/0x8e0 kernel/time/hrtimer.c:1903
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1045 [inline]
__sysvec_apic_timer_interrupt+0x10b/0x3c0 arch/x86/kernel/apic/apic.c:1062
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
sysvec_apic_timer_interrupt+0x9f/0xc0 arch/x86/kernel/apic/apic.c:1056
</IRQ>
<TASK>
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:__local_bh_enable_ip+0x5c/0x120 kernel/softirq.c:430
Code: e0 07 48 c1 e9 03 83 c0 03 0f b6 14 11 38 d0 7c 08 84 d2 0f 85 c3 00 00 00 8b 05 03 ff 0a 0f 85 c0 74 0b 65 8b 05 cc 27 35 12 <85> c0 74 57 9c 58 fa f6 c4 02 75 60 65 8b 05 a1 e0 34 12 25 00 ff
RSP: 0018:ffffc90000ac7b50 EFLAGS: 00000202
RAX: 0000000000000000 RBX: 0000000000000201 RCX: 1ffffffff2111fce
RDX: 0000000000000000 RSI: 0000000000000201 RDI: ffffffff8b42b109
RBP: ffffffff8b42b109 R08: 0000000000000000 R09: ffffed100ba56fb8
R10: ffff88805d2b7dc3 R11: ffff8881422f2ff0 R12: ffff88805d2b7dc0
R13: ffff88805d300fb8 R14: ffffffff8b42a440 R15: 00000000000001f7
spin_unlock_bh include/linux/spinlock.h:396 [inline]
__batadv_dat_purge.part.0+0x279/0x3a0 net/batman-adv/distributed-arp-table.c:185
__batadv_dat_purge net/batman-adv/distributed-arp-table.c:166 [inline]
batadv_dat_purge+0x4b/0xa0 net/batman-adv/distributed-arp-table.c:204
process_one_work+0x9ba/0x1b20 kernel/workqueue.c:3257
process_scheduled_works kernel/workqueue.c:3340 [inline]
worker_thread+0x6c8/0xf10 kernel/workqueue.c:3421
kthread+0x3c5/0x780 kernel/kthread.c:463
ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
</TASK>
sched: DL replenish lagged too much