rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P6117/1:b..l P8855/1:b..l P9074/1:b..l
rcu: (detected by 1, t=10503 jiffies, g=35101, q=594 ncpus=2)
task:syz.3.926 state:R running task stack:26712 pid:9074 tgid:9074 ppid:5824 task_flags:0x40044c flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5295 [inline]
__schedule+0x1585/0x5310 kernel/sched/core.c:6907
preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:7091
preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
__raw_spin_unlock include/linux/spinlock_api_smp.h:169 [inline]
_raw_spin_unlock+0x3f/0x50 kernel/locking/spinlock.c:186
spin_unlock include/linux/spinlock.h:389 [inline]
zap_pte_range mm/memory.c:1961 [inline]
zap_pmd_range mm/memory.c:2023 [inline]
zap_pud_range mm/memory.c:2051 [inline]
zap_p4d_range mm/memory.c:2072 [inline]
unmap_page_range+0x3b71/0x48f0 mm/memory.c:2093
unmap_single_vma mm/memory.c:2135 [inline]
unmap_vmas+0x48f/0x6a0 mm/memory.c:2173
exit_mmap+0x283/0xa00 mm/mmap.c:1302
__mmput+0x118/0x430 kernel/fork.c:1174
exit_mm+0x168/0x220 kernel/exit.c:581
do_exit+0x62e/0x2320 kernel/exit.c:959
do_group_exit+0x21b/0x2d0 kernel/exit.c:1112
get_signal+0x1284/0x1330 kernel/signal.c:3034
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:226 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:325 [inline]
do_syscall_64+0x32d/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa63879bf79
RSP: 002b:00007ffc325ad788 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: ffffffffffffff92 RBX: 00000000000678d7 RCX: 00007fa63879bf79
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007fa638a15fac
RBP: 0000000000000032 R08: 3fffffffffffffff R09: 0000000000000000
R10: 00007ffc325ad890 R11: 0000000000000246 R12: 00007ffc325ad8b0
R13: 00007fa638a15fac R14: 0000000000067909 R15: 00007ffc325ad890
task:kworker/u8:11 state:R running task stack:22336 pid:8855 tgid:8855 ppid:2 task_flags:0x4208060 flags:0x00080000
Workqueue: bat_events batadv_mcast_mla_update
Call Trace:
context_switch kernel/sched/core.c:5295 [inline]
__schedule+0x1585/0x5310 kernel/sched/core.c:6907
preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7234
irqentry_exit+0x599/0x620 kernel/entry/common.c:239
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:unwind_next_frame+0x484/0x23c0 arch/x86/kernel/unwind_orc.c:520
Code: d2 84 c0 48 0f 45 d1 48 89 15 b8 a3 ab 11 48 85 d2 0f 84 40 02 00 00 4c 8d 62 04 4c 8d 6a 05 4c 89 e0 48 c1 e8 03 0f b6 04 28 <84> c0 0f 85 66 18 00 00 4c 89 e8 48 c1 e8 03 0f b6 04 28 84 c0 0f
RSP: 0018:ffffc9000503f458 EFLAGS: 00000a07
RAX: 0000000000000000 RBX: ffffffff90291dac RCX: ffffffff90291db0
RDX: ffffffff90a4cde8 RSI: ffffffff90a4cddc RDI: ffffffff8c27a420
RBP: dffffc0000000000 R08: 0000000000000003 R09: ffffffff8e7602e0
R10: ffffc9000503f578 R11: ffffffff81b0c280 R12: ffffffff90a4cdec
R13: ffffffff90a4cded R14: ffffc9000503f528 R15: ffffffff90291dac
arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:57 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:584
poison_slab_object mm/kasan/common.c:253 [inline]
__kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285
kasan_slab_free include/linux/kasan.h:235 [inline]
slab_free_hook mm/slub.c:2687 [inline]
slab_free mm/slub.c:6124 [inline]
kfree+0x1c1/0x630 mm/slub.c:6442
batadv_mcast_mla_list_free net/batman-adv/multicast.c:667 [inline]
__batadv_mcast_mla_update net/batman-adv/multicast.c:924 [inline]
batadv_mcast_mla_update+0x344a/0x3710 net/batman-adv/multicast.c:946
process_one_work+0x949/0x1650 kernel/workqueue.c:3279
process_scheduled_works kernel/workqueue.c:3362 [inline]
worker_thread+0xb46/0x1140 kernel/workqueue.c:3443
kthread+0x388/0x470 kernel/kthread.c:467
ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
task:udevd state:R running task stack:23552 pid:6117 tgid:6117 ppid:5191 task_flags:0x400140 flags:0x00080800
Call Trace:
context_switch kernel/sched/core.c:5295 [inline]
__schedule+0x1585/0x5310 kernel/sched/core.c:6907
preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7234
irqentry_exit+0x599/0x620 kernel/entry/common.c:239
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lock_release+0x2d7/0x3d0 kernel/locking/lockdep.c:5893
Code: 55 7a 11 00 00 00 00 eb b5 e8 d5 b2 0b 0a f7 c3 00 02 00 00 74 b9 65 48 8b 05 55 10 7a 11 48 3b 44 24 28 75 44 fb 48 83 c4 30 <5b> 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc cc 48 8d 3d 42 19 73
RSP: 0018:ffffc9000499f0c0 EFLAGS: 00000286
RAX: 4c32d92dbef1f800 RBX: 0000000000000202 RCX: 0000000000000046
RDX: 0000000000000000 RSI: ffffffff8e162941 RDI: ffffffff8c27a480
RBP: ffff88801d708b18 R08: ffffc9000499f2f0 R09: 0000000000000000
R10: ffffc9000499f218 R11: fffff52000933e45 R12: 0000000000000000
R13: 0000000000000000 R14: ffffffff8e7602e0 R15: ffff88801d708000
rcu_lock_release include/linux/rcupdate.h:322 [inline]
rcu_read_unlock include/linux/rcupdate.h:881 [inline]
class_rcu_destructor include/linux/rcupdate.h:1193 [inline]
unwind_next_frame+0x1aaa/0x23c0 arch/x86/kernel/unwind_orc.c:695
arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122
save_stack+0x122/0x230 mm/page_owner.c:165
__reset_page_owner+0x71/0x1f0 mm/page_owner.c:320
reset_page_owner include/linux/page_owner.h:25 [inline]
__free_pages_prepare mm/page_alloc.c:1433 [inline]
free_unref_folios+0xed5/0x16d0 mm/page_alloc.c:3040
folios_put_refs+0x789/0x8d0 mm/swap.c:1002
folio_batch_release include/linux/pagevec.h:101 [inline]
shmem_undo_range+0x52c/0x1660 mm/shmem.c:1149
shmem_truncate_range mm/shmem.c:1277 [inline]
shmem_evict_inode+0x240/0x9e0 mm/shmem.c:1407
evict+0x61e/0xb10 fs/inode.c:846
__dentry_kill+0x1a2/0x5e0 fs/dcache.c:670
finish_dput+0xc9/0x480 fs/dcache.c:879
__fput+0x691/0xa70 fs/file_table.c:477
task_work_run+0x1d9/0x270 kernel/task_work.c:233
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
__exit_to_user_mode_loop kernel/entry/common.c:67 [inline]
exit_to_user_mode_loop+0xed/0x480 kernel/entry/common.c:98
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:325 [inline]
do_syscall_64+0x32d/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fbdc52a7407
RSP: 002b:00007ffe71254f60 EFLAGS: 00000202 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 00007fbdc5a01880 RCX: 00007fbdc52a7407
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000008
RBP: 00007fbdc5a016e8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000002
R13: 000055fc0b545190 R14: 0000000000000008 R15: 000055fc0b551320
rcu: rcu_preempt kthread starved for 9592 jiffies! g35101 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:27744 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5295 [inline]
__schedule+0x1585/0x5310 kernel/sched/core.c:6907
__schedule_loop kernel/sched/core.c:6989 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7004
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:467
ret_from_fork+0x51e/0xb90 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:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 9062 Comm: syz.4.924 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026
RIP: 0010:check_preemption_disabled+0x1/0xe0 lib/smp_processor_id.c:13
Code: 20 a4 27 8c 48 c7 c6 60 a4 27 8c eb 1c 66 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 55 <41> 57 41 56 53 65 8b 05 57 43 6e 07 65 8b 0d 4c 43 6e 07 f7 c1 ff
RSP: 0018:ffffc9000673fc48 EFLAGS: 00000046
RAX: 0000000080000000 RBX: ffffffff8bb00f17 RCX: 1ffff1100536347e
RDX: 1ffff110053634f8 RSI: ffffffff8df56af5 RDI: ffffffff8c27a480
RBP: ffff888029b1a3e0 R08: ffff888029b19e47 R09: 1ffff110053633c8
R10: dffffc0000000000 R11: ffffed10053633c9 R12: ffff888029b1a7b0
R13: 1ffff11006a91585 R14: ffff88803548ac2c R15: ffff888029b19e40
FS: 00007f0d066636c0(0000) GS:ffff888125463000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f10e6de96c0 CR3: 00000000207a0000 CR4: 00000000003526f0
Call Trace:
lockdep_hardirqs_off+0x8d/0xd0 kernel/locking/lockdep.c:4495
trace_hardirqs_off+0x12/0x40 kernel/trace/trace_preemptirq.c:104
__raw_spin_lock_irq include/linux/spinlock_api_smp.h:140 [inline]
_raw_spin_lock_irq+0x17/0x50 kernel/locking/spinlock.c:170
spin_lock_irq include/linux/spinlock.h:371 [inline]
get_signal+0x238/0x1330 kernel/signal.c:2823
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:226 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:325 [inline]
do_syscall_64+0x32d/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f0d0579bf77
Code: 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89
RSP: 002b:00007f0d066630e8 EFLAGS: 00000246
RAX: 00000000000000ca RBX: 00007f0d05a15fa8 RCX: 00007f0d0579bf79
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f0d05a15fa8
RBP: 00007f0d05a15fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f0d05a16038 R14: 00007ffc7d7213e0 R15: 00007ffc7d7214c8