rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P5279/1:b..l
	(detected by 1, t=10502 jiffies, g=14445, q=27)
task:kworker/u4:17   state:R  running task     stack:27424 pid: 5279 ppid:     2 flags:0x00004000
Workqueue: bat_events batadv_nc_worker
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5027 [inline]
 __schedule+0x12c4/0x45b0 kernel/sched/core.c:6373
 preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6777
 irqentry_exit+0x53/0x80 kernel/entry/common.c:432
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:lock_acquire+0x252/0x4f0 kernel/locking/lockdep.c:5627
Code: 2b 00 74 08 4c 89 f7 e8 9c 9e 67 00 f6 44 24 61 02 0f 85 84 01 00 00 41 f7 c7 00 02 00 00 74 01 fb 48 c7 44 24 40 0e 36 e0 45 <4b> c7 44 25 00 00 00 00 00 43 c7 44 25 09 00 00 00 00 43 c7 44 25
RSP: 0018:ffffc90002d5fa80 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 1ffff920005abf5c RCX: 1ffff920005abefc
RDX: dffffc0000000000 RSI: ffffffff8aab3e20 RDI: ffffffff8af9f2c0
RBP: ffffc90002d5fbd8 R08: dffffc0000000000 R09: fffffbfff2131821
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff920005abf58
R13: dffffc0000000000 R14: ffffc90002d5fae0 R15: 0000000000000246
 rcu_lock_acquire+0x2a/0x30 include/linux/rcupdate.h:312
 rcu_read_lock include/linux/rcupdate.h:739 [inline]
 batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:412 [inline]
 batadv_nc_worker+0xc1/0x5b0 net/batman-adv/network-coding.c:723
 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310
 worker_thread+0xaca/0x1280 kernel/workqueue.c:2457
 kthread+0x3f6/0x4f0 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
rcu: rcu_preempt kthread starved for 10528 jiffies! g14445 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:26752 pid:   15 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5027 [inline]
 __schedule+0x12c4/0x45b0 kernel/sched/core.c:6373
 schedule+0x11b/0x1f0 kernel/sched/core.c:6456
 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1914
 rcu_gp_fqs_loop+0x2bf/0x1080 kernel/rcu/tree.c:1972
 rcu_gp_kthread+0xa4/0x360 kernel/rcu/tree.c:2145
 kthread+0x3f6/0x4f0 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
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: 5306 Comm: syz.0.147 Not tainted 5.15.178-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
RIP: 0010:check_kcov_mode kernel/kcov.c:183 [inline]
RIP: 0010:write_comp_data kernel/kcov.c:227 [inline]
RIP: 0010:__sanitizer_cov_trace_const_cmp4+0x30/0x80 kernel/kcov.c:293
Code: 8b 15 c4 e6 81 7e 65 8b 05 c5 e6 81 7e 25 00 01 ff 00 74 10 3d 00 01 00 00 75 5b 83 ba 34 16 00 00 00 74 52 8b 82 10 16 00 00 <83> f8 03 75 47 48 8b 8a 18 16 00 00 44 8b 92 14 16 00 00 49 c1 e2
RSP: 0018:ffffc90003257c28 EFLAGS: 00000246
RAX: 0000000000000002 RBX: 0000000080000000 RCX: 0000000000080000
RDX: ffff888023de0000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90003257e50 R08: ffffffff8413e424 R09: fffffbfff1c150ee
R10: 0000000000000000 R11: dffffc0000000001 R12: 00000000000000c0
R13: ffffc90003257f58 R14: ffffc90003257cc0 R15: 00007f22753cfb68
FS:  00007f22753d06c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f0c475ce108 CR3: 000000005e51e000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 _copy_from_user+0x54/0x170 lib/usercopy.c:15
 copy_from_user include/linux/uaccess.h:192 [inline]
 restore_sigcontext+0xce/0x710 arch/x86/kernel/signal.c:91
 __do_sys_rt_sigreturn+0x190/0x250 arch/x86/kernel/signal.c:674
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f2277503359
Code: 64 c7 00 16 00 00 00 b8 ff ff ff ff c3 0f 1f 40 00 90 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 c7 c0 0f 00 00 00 0f 05 <0f> 1f 80 00 00 00 00 48 81 ec 48 01 00 00 49 89 d0 64 48 8b 04 25
RSP: 002b:00007f22753cfb40 EFLAGS: 00000206 ORIG_RAX: 000000000000000f
RAX: ffffffffffffffda RBX: 00007f227777ffa8 RCX: 00007f2277503359
RDX: 00007f22753cfb40 RSI: 00007f22753cfc70 RDI: 0000000000000021
RBP: 00007f227777ffa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 00007f227777ffac
R13: 0000000000000000 R14: 00007ffea959b890 R15: 00007ffea959b978
 </TASK>