rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	0-...!: (10500 ticks this GP) idle=179c/1/0x4000000000000000 softirq=33385/33385 fqs=1195
rcu: 	(t=10502 jiffies g=32561 q=2982 ncpus=2)
rcu: rcu_preempt kthread timer wakeup didn't happen for 8104 jiffies! g32561 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=1 timer-softirq=14621
rcu: rcu_preempt kthread starved for 8107 jiffies! g32561 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:27688 pid:17    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 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
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 11 Comm: kworker/u4:0 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Workqueue: bat_events batadv_nc_worker
RIP: 0010:pv_wait_head_or_lock kernel/locking/qspinlock_paravirt.h:434 [inline]
RIP: 0010:__pv_queued_spin_lock_slowpath+0x532/0x9d0 kernel/locking/qspinlock.c:511
Code: 00 41 c6 45 00 00 48 8b 44 24 10 42 0f b6 04 38 84 c0 0f 85 1b 01 00 00 48 8b 44 24 08 c6 00 01 41 bd 00 80 ff ff eb 07 f3 90 <41> ff c5 74 47 43 0f b6 04 3e 84 c0 75 2b 80 3b 00 75 eb 48 89 df
RSP: 0018:ffffc900001f0900 EFLAGS: 00000206
RAX: 0000000000000000 RBX: ffff88807ac55280 RCX: ffff888019e7bc00
RDX: 0000000000000100 RSI: ffffffff8aaaba20 RDI: ffffffff8afc7040
RBP: ffffc900001f09f0 R08: ffffffff90da562f R09: 1ffffffff21b4ac5
R10: dffffc0000000000 R11: fffffbfff21b4ac6 R12: 1ffff110171e0001
R13: 00000000ffff8d9d R14: 1ffff1100f58aa50 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f127889ff54 CR3: 0000000024b0b000 CR4: 00000000003506e0
Call Trace:
 <IRQ>
 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:586 [inline]
 queued_spin_lock_slowpath arch/x86/include/asm/qspinlock.h:51 [inline]
 queued_spin_lock include/asm-generic/qspinlock.h:114 [inline]
 do_raw_spin_lock+0x24e/0x2c0 kernel/locking/spinlock_debug.c:115
 spin_lock include/linux/spinlock.h:351 [inline]
 __xfrm_state_delete+0xba/0x800 net/xfrm/xfrm_state.c:746
 xfrm_timer_handler+0x1c3/0x9e0 net/xfrm/xfrm_state.c:644
 __run_hrtimer kernel/time/hrtimer.c:1755 [inline]
 __hrtimer_run_queues+0x51e/0xc40 kernel/time/hrtimer.c:1819
 hrtimer_run_softirq+0x187/0x2b0 kernel/time/hrtimer.c:1836
 handle_softirqs+0x280/0x820 kernel/softirq.c:578
 __do_softirq kernel/softirq.c:612 [inline]
 invoke_softirq kernel/softirq.c:452 [inline]
 __irq_exit_rcu+0xc7/0x190 kernel/softirq.c:661
 irq_exit_rcu+0x9/0x20 kernel/softirq.c:673
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline]
 sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1088
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
RIP: 0010:__preempt_count_add arch/x86/include/asm/preempt.h:80 [inline]
RIP: 0010:rcu_is_watching+0x0/0xb0 kernel/rcu/tree.c:699
Code: 0f 84 2c ff ff ff eb 99 e8 2d 60 fe 08 48 c7 c7 40 6a d3 8c 4c 89 f6 e8 2e ee e1 02 e9 53 ff ff ff 66 0f 1f 84 00 00 00 00 00 <f3> 0f 1e fa 41 57 41 56 53 65 ff 05 f8 21 94 7e e8 0b 76 fe 08 89
RSP: 0018:ffffc90000107b58 EFLAGS: 00000202
RAX: ffffffff8a365213 RBX: 0000000000000001 RCX: 0000000000000000
RDX: ffff888019e7bc00 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffff888059f60e38 R08: dffffc0000000000 R09: 1ffffffff21b4aa0
R10: dffffc0000000000 R11: fffffbfff21b4aa1 R12: dffffc0000000000
R13: ffffffff8a3651e2 R14: ffff88805c57cc80 R15: 00000000000001c7
 rcu_read_lock include/linux/rcupdate.h:787 [inline]
 batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline]
 batadv_nc_worker+0x10c/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>
CPU: 0 PID: 9485 Comm: syz.5.839 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:27 [inline]
RIP: 0010:check_kcov_mode kernel/kcov.c:182 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x10/0x60 kernel/kcov.c:216
Code: 89 fb e8 13 00 00 00 48 8b 3d bc 01 c5 0c 48 89 de 5b e9 a3 75 56 00 cc cc cc f3 0f 1e fa 48 8b 04 24 65 48 8b 0d 50 2a 7e 7e <65> 8b 15 51 2a 7e 7e 81 e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75
RSP: 0018:ffffc90014637198 EFLAGS: 00000287
RAX: ffffffff891e31c0 RBX: 0000000003000000 RCX: ffff88805b2d1e00
RDX: ffff88805b2d1e00 RSI: 0000000003000000 RDI: 0000000001000000
RBP: ffffc900146372f0 R08: dffffc0000000000 R09: 1ffffffff21b4aa0
R10: dffffc0000000000 R11: fffffbfff21b4aa1 R12: 0000000001000000
R13: 0000000000000001 R14: ffff88805be89000 R15: dffffc0000000000
FS:  00007ff464a136c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fa6de3912f8 CR3: 000000007d447000 CR4: 00000000003506f0
Call Trace:
 <TASK>
 xfrm_state_lookup_spi_proto net/xfrm/xfrm_state.c:1477 [inline]
 xfrm_alloc_spi+0x4d0/0x11f0 net/xfrm/xfrm_state.c:2302
 xfrm_alloc_userspi+0x5d1/0xa90 net/xfrm/xfrm_user.c:1623
 xfrm_user_rcv_msg+0x596/0x870 net/xfrm/xfrm_user.c:3169
 netlink_rcv_skb+0x216/0x480 net/netlink/af_netlink.c:2545
 xfrm_netlink_rcv+0x79/0x90 net/xfrm/xfrm_user.c:3191
 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline]
 netlink_unicast+0x751/0x8d0 net/netlink/af_netlink.c:1346
 netlink_sendmsg+0x8c1/0xbe0 net/netlink/af_netlink.c:1894
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg net/socket.c:745 [inline]
 ____sys_sendmsg+0x5bf/0x950 net/socket.c:2595
 ___sys_sendmsg+0x220/0x290 net/socket.c:2649
 __sys_sendmsg net/socket.c:2678 [inline]
 __do_sys_sendmsg net/socket.c:2687 [inline]
 __se_sys_sendmsg+0x1a5/0x270 net/socket.c:2685
 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: 0033:0x7ff463b8ebe9
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:00007ff464a13038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007ff463dc5fa0 RCX: 00007ff463b8ebe9
RDX: 0000000000040858 RSI: 0000200000001680 RDI: 0000000000000003
RBP: 00007ff463c11e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ff463dc6038 R14: 00007ff463dc5fa0 R15: 00007ffea385dd98
 </TASK>