rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P9965/1:b..l P5963/1:b..l P12/1:b..l P50/1:b..l
rcu: 	(detected by 1, t=10502 jiffies, g=33773, q=268 ncpus=2)
task:kworker/u8:3    state:R  running task     stack:23248 pid:50    tgid:50    ppid:2      task_flags:0x4208060 flags:0x00080000
Workqueue: bat_events batadv_iv_send_outstanding_bat_ogm_packet
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5256 [inline]
 __schedule+0x1139/0x6150 kernel/sched/core.c:6863
 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7190
 irqentry_exit+0x1d8/0x8c0 kernel/entry/common.c:216
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lock_acquire+0x62/0x330 kernel/locking/lockdep.c:5872
Code: a4 18 12 83 f8 07 0f 87 a2 02 00 00 89 c0 48 0f a3 05 72 b4 ee 0e 0f 82 74 02 00 00 8b 35 0a e5 ee 0e 85 f6 0f 85 8d 00 00 00 <48> 8b 44 24 30 65 48 2b 05 89 a4 18 12 0f 85 ad 02 00 00 48 83 c4
RSP: 0018:ffffc90000bb79c8 EFLAGS: 00000206
RAX: 0000000000000046 RBX: ffffffff8e3c9620 RCX: 00000000e7dc67b2
RDX: 0000000000000000 RSI: ffffffff8daa7b4b RDI: ffffffff8bf2b380
RBP: 0000000000000002 R08: 00000000d5697092 R09: 000000002d569709
R10: 0000000000000002 R11: ffff888021e90b30 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
 rcu_read_lock include/linux/rcupdate.h:867 [inline]
 batadv_iv_ogm_slide_own_bcast_window net/batman-adv/bat_iv_ogm.c:761 [inline]
 batadv_iv_ogm_schedule_buff+0x5d0/0x14c0 net/batman-adv/bat_iv_ogm.c:833
 batadv_iv_ogm_schedule net/batman-adv/bat_iv_ogm.c:873 [inline]
 batadv_iv_ogm_schedule net/batman-adv/bat_iv_ogm.c:866 [inline]
 batadv_iv_send_outstanding_bat_ogm_packet+0x329/0x920 net/batman-adv/bat_iv_ogm.c:1709
 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>
task:kworker/u8:0    state:R  running task     stack:23544 pid:12    tgid:12    ppid:2      task_flags:0x4208160 flags:0x00080000
Workqueue: events_unbound cfg80211_wiphy_work
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5256 [inline]
 __schedule+0x1139/0x6150 kernel/sched/core.c:6863
 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7190
 irqentry_exit+0x1d8/0x8c0 kernel/entry/common.c:216
 asm_sysvec_call_function_single+0x1a/0x20 arch/x86/include/asm/idtentry.h:704
RIP: 0010:lock_release+0x183/0x2d0 kernel/locking/lockdep.c:5893
Code: 0f c1 05 48 f1 18 12 83 f8 01 0f 85 03 01 00 00 9c 58 f6 c4 02 0f 85 ee 00 00 00 41 f7 c5 00 02 00 00 74 01 fb 48 8b 44 24 10 <65> 48 2b 05 dd a9 18 12 0f 85 32 01 00 00 48 83 c4 18 5b 41 5c 41
RSP: 0018:ffffc90000117598 EFLAGS: 00000206
RAX: acdaf29bb1413700 RBX: ffffffff8e3c9620 RCX: ffffc900001175a4
RDX: 0000000000000003 RSI: ffffffff8daa7b4b RDI: ffffffff8bf2b380
RBP: 0000000000000001 R08: 0000000000000001 R09: 00000000ccd1ae9b
R10: 0000000000000002 R11: 0000000000011d85 R12: ffffffff816cb9a4
R13: 0000000000000206 R14: ffff88801d6c4980 R15: 0000000000000004
 rcu_lock_release include/linux/rcupdate.h:341 [inline]
 rcu_read_unlock include/linux/rcupdate.h:897 [inline]
 class_rcu_destructor include/linux/rcupdate.h:1195 [inline]
 unwind_next_frame+0x3f9/0x20b0 arch/x86/kernel/unwind_orc.c:495
 arch_stack_walk+0x94/0x100 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:56
 kasan_save_track+0x14/0x30 mm/kasan/common.c:77
 kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:584
 poison_slab_object mm/kasan/common.c:252 [inline]
 __kasan_slab_free+0x5f/0x80 mm/kasan/common.c:284
 kasan_slab_free include/linux/kasan.h:234 [inline]
 slab_free_hook mm/slub.c:2540 [inline]
 slab_free mm/slub.c:6668 [inline]
 kmem_cache_free+0x2d8/0x770 mm/slub.c:6779
 skb_kfree_head net/core/skbuff.c:1066 [inline]
 skb_kfree_head net/core/skbuff.c:1063 [inline]
 skb_free_head+0x1b7/0x210 net/core/skbuff.c:1080
 skb_release_data+0x795/0x9e0 net/core/skbuff.c:1107
 skb_release_all net/core/skbuff.c:1182 [inline]
 __kfree_skb net/core/skbuff.c:1196 [inline]
 sk_skb_reason_drop+0x129/0x1a0 net/core/skbuff.c:1234
 kfree_skb_reason include/linux/skbuff.h:1322 [inline]
 kfree_skb include/linux/skbuff.h:1331 [inline]
 ieee80211_iface_work+0x42f/0x1350 net/mac80211/iface.c:1792
 cfg80211_wiphy_work+0x3fb/0x560 net/wireless/core.c:438
 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>
task:kworker/u8:16   state:R  running task     stack:23800 pid:5963  tgid:5963  ppid:2      task_flags:0x4208060 flags:0x00080000
Workqueue: events_unbound cfg80211_wiphy_work
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5256 [inline]
 __schedule+0x1139/0x6150 kernel/sched/core.c:6863
 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7190
 irqentry_exit+0x1d8/0x8c0 kernel/entry/common.c:216
 asm_sysvec_call_function_single+0x1a/0x20 arch/x86/include/asm/idtentry.h:704
RIP: 0010:trace_lock_release include/trace/events/lock.h:69 [inline]
RIP: 0010:lock_release+0x45/0x2d0 kernel/locking/lockdep.c:5879
Code: 49 ab 18 12 48 89 44 24 10 31 c0 0f 1f 44 00 00 65 8b 05 62 ab 18 12 83 f8 07 0f 87 1e 02 00 00 89 c0 48 0f a3 05 eb ba ee 0e <0f> 82 b1 01 00 00 8b 3d 83 eb ee 0e 85 ff 0f 84 25 01 00 00 65 8b
RSP: 0018:ffffc900047bf408 EFLAGS: 00000297
RAX: 0000000000000000 RBX: ffffffff8e3c9620 RCX: ffffffff912fb701
RDX: 0000000000000000 RSI: ffffffff816cb9a4 RDI: ffffffff8e3c9620
RBP: 0000000000000001 R08: ffffffff912fb76e R09: 00000000ccd1ae9b
R10: 0000000000000002 R11: 000000000001288a R12: ffffffff816cb9a4
R13: ffffc900047bf4c0 R14: ffffc900047bf820 R15: ffffc900047bf4f4
 rcu_lock_release include/linux/rcupdate.h:341 [inline]
 rcu_read_unlock include/linux/rcupdate.h:897 [inline]
 class_rcu_destructor include/linux/rcupdate.h:1195 [inline]
 unwind_next_frame+0x3f9/0x20b0 arch/x86/kernel/unwind_orc.c:495
 arch_stack_walk+0x94/0x100 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:56
 kasan_save_track+0x14/0x30 mm/kasan/common.c:77
 kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:584
 poison_slab_object mm/kasan/common.c:252 [inline]
 __kasan_slab_free+0x5f/0x80 mm/kasan/common.c:284
 kasan_slab_free include/linux/kasan.h:234 [inline]
 slab_free_hook mm/slub.c:2540 [inline]
 slab_free mm/slub.c:6668 [inline]
 kfree+0x2f8/0x6e0 mm/slub.c:6876
 ieee80211_rx_mgmt_probe_beacon net/mac80211/ibss.c:1576 [inline]
 ieee80211_ibss_rx_queued_mgmt+0x1ab4/0x2fc0 net/mac80211/ibss.c:1602
 ieee80211_iface_process_skb net/mac80211/iface.c:1736 [inline]
 ieee80211_iface_work+0xe28/0x1350 net/mac80211/iface.c:1790
 cfg80211_wiphy_work+0x3fb/0x560 net/wireless/core.c:438
 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>
task:syz.2.1152      state:R  running task     stack:25728 pid:9965  tgid:9955  ppid:5814   task_flags:0x400040 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5256 [inline]
 __schedule+0x1139/0x6150 kernel/sched/core.c:6863
 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7190
 irqentry_exit+0x1d8/0x8c0 kernel/entry/common.c:216
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:__sanitizer_cov_trace_pc+0x41/0x70 kernel/kcov.c:217
Code: a9 00 01 ff 00 74 1d f6 c4 01 74 43 a9 00 00 0f 00 75 3c a9 00 00 f0 00 75 35 8b 82 6c 16 00 00 85 c0 74 2b 8b 82 48 16 00 00 <83> f8 02 75 20 48 8b 8a 50 16 00 00 8b 92 4c 16 00 00 48 8b 01 48
RSP: 0000:ffffc9000f5d7630 EFLAGS: 00000246
RAX: 0000000000000002 RBX: 000020000008b000 RCX: ffffffff82135820
RDX: ffff888026068000 RSI: ffffffff82135a0c RDI: 0000000000000005
RBP: 0000000000000001 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: ffff888026068b30 R12: ffffc9000f5d7690
R13: ffff888053ddd000 R14: ffffc9000f5d78d0 R15: 0000000000000067
 rcu_read_lock include/linux/rcupdate.h:868 [inline]
 ___pte_offset_map+0x23c/0x380 mm/pgtable-generic.c:288
 __pte_offset_map include/linux/mm.h:3346 [inline]
 __pte_offset_map_lock+0x8d/0x310 mm/pgtable-generic.c:399
 pte_offset_map_lock include/linux/mm.h:3361 [inline]
 do_anonymous_page+0x241/0x2190 mm/memory.c:5198
 do_pte_missing mm/memory.c:4399 [inline]
 handle_pte_fault mm/memory.c:6273 [inline]
 __handle_mm_fault+0x1ecf/0x2bb0 mm/memory.c:6411
 handle_mm_fault+0x3fe/0xad0 mm/memory.c:6580
 do_user_addr_fault+0x7a6/0x1370 arch/x86/mm/fault.c:1387
 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: 0010:fault_in_readable+0x135/0x1d0 mm/gup.c:2161
Code: a1 0e b5 ff 48 85 db 0f 84 9c 00 00 00 e8 c3 13 b5 ff 48 89 de 48 89 ef e8 c8 0d b5 ff 48 39 eb 73 1d e8 ae 13 b5 ff 45 89 f7 <8a> 03 31 ff 44 89 fe 88 44 24 28 e8 3b 0e b5 ff 45 85 ff 74 a8 e8
RSP: 0000:ffffc9000f5d7b08 EFLAGS: 00050287
RAX: 0000000000035565 RBX: 000020000008b000 RCX: ffffc9000c759000
RDX: 0000000000080000 RSI: ffffffff8209d2e2 RDI: 0000000000000006
RBP: 000020000008c000 R08: 0000000000000006 R09: 000020000008b000
R10: 000020000008c000 R11: 0000000000000000 R12: 000020000008b000
R13: 0000000000001000 R14: 0000000000000000 R15: 0000000000000000
 fault_in_iov_iter_readable+0x101/0x2c0 lib/iov_iter.c:106
 generic_perform_write+0x7ad/0x900 mm/filemap.c:4363
 shmem_file_write_iter+0x10e/0x140 mm/shmem.c:3490
 new_sync_write fs/read_write.c:593 [inline]
 vfs_write+0x7d3/0x11d0 fs/read_write.c:686
 ksys_write+0x12a/0x250 fs/read_write.c:738
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7a5a58f749
RSP: 002b:00007f7a5b49f038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f7a5a7e6090 RCX: 00007f7a5a58f749
RDX: 000000000208e24b RSI: 0000200000000000 RDI: 0000000000000005
RBP: 00007f7a5a613f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f7a5a7e6128 R14: 00007f7a5a7e6090 R15: 00007fff260aaec8
 </TASK>
rcu: rcu_preempt kthread starved for 10636 jiffies! g33773 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:27936 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>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:82
Code: c6 5f 02 c3 cc cc cc cc 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 13 59 12 00 fb f4 <e9> cc 35 03 00 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90
RSP: 0018:ffffc90000197de8 EFLAGS: 000002c6
RAX: 000000000157ad8d RBX: 0000000000000001 RCX: ffffffff8b7806d9
RDX: 0000000000000000 RSI: ffffffff8dacdbe3 RDI: ffffffff8bf2b380
RBP: ffffed1003b56498 R08: 0000000000000001 R09: ffffed10170a673d
R10: ffff8880b85339eb R11: ffff88801dab2ff0 R12: 0000000000000001
R13: ffff88801dab24c0 R14: ffffffff9088afd0 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8881249f6000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f7e2af086c8 CR3: 000000002ad97000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline]
 default_idle+0x13/0x20 arch/x86/kernel/process.c:767
 default_idle_call+0x6c/0xb0 kernel/sched/idle.c:122
 cpuidle_idle_call kernel/sched/idle.c:191 [inline]
 do_idle+0x38d/0x510 kernel/sched/idle.c:332
 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:430
 start_secondary+0x21d/0x2d0 arch/x86/kernel/smpboot.c:312
 common_startup_64+0x13e/0x148
 </TASK>