rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P4434/1:b..l P5167/1:b..l P4278/1:b..l
(detected by 0, t=10502 jiffies, g=13657, q=97 ncpus=2)
task:syz-executor state:R running task stack:22096 pid:4278 ppid:4263 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5245 [inline]
__schedule+0x11d1/0x40e0 kernel/sched/core.c:6562
preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:6731
preempt_schedule+0xbc/0xd0 kernel/sched/core.c:6755
preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:34
unwind_next_frame+0x1892/0x20b0 arch/x86/kernel/unwind_orc.c:629
arch_stack_walk+0x10c/0x140 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0xa6/0xf0 kernel/stacktrace.c:122
save_stack+0x121/0x230 mm/page_owner.c:127
__reset_page_owner+0x51/0x1a0 mm/page_owner.c:148
reset_page_owner include/linux/page_owner.h:24 [inline]
free_pages_prepare mm/page_alloc.c:1486 [inline]
free_pcp_prepare mm/page_alloc.c:1536 [inline]
free_unref_page_prepare+0x8b4/0x9a0 mm/page_alloc.c:3413
free_unref_page_list+0xbb/0x8e0 mm/page_alloc.c:3554
release_pages+0x1fa6/0x2220 mm/swap.c:1035
__pagevec_release+0x6d/0xe0 mm/swap.c:1055
pagevec_release include/linux/pagevec.h:71 [inline]
folio_batch_release include/linux/pagevec.h:135 [inline]
shmem_undo_range+0x7c2/0x20c0 mm/shmem.c:946
shmem_truncate_range mm/shmem.c:1062 [inline]
shmem_evict_inode+0x25b/0xa80 mm/shmem.c:1171
evict+0x4c9/0x8d0 fs/inode.c:705
do_unlinkat+0x388/0x580 fs/namei.c:4405
__do_sys_unlink fs/namei.c:4446 [inline]
__se_sys_unlink fs/namei.c:4444 [inline]
__x64_sys_unlink+0x45/0x50 fs/namei.c:4444
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fb9cd59b907
RSP: 002b:00007ffe1dbd2ce8 EFLAGS: 00000206 ORIG_RAX: 0000000000000057
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fb9cd59b907
RDX: 00007ffe1dbd2d10 RSI: 00007ffe1dbd2da0 RDI: 00007ffe1dbd2da0
RBP: 00007ffe1dbd2da0 R08: 00007ffe1dbd3da0 R09: 00000000ffffffff
R10: 0000000000000100 R11: 0000000000000206 R12: 00007ffe1dbd3e30
R13: 00007fb9cd632048 R14: 0000000000025028 R15: 00007ffe1dbd3e70
task:syz.3.190 state:R running task stack:26224 pid:5167 ppid:4268 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5245 [inline]
__schedule+0x11d1/0x40e0 kernel/sched/core.c:6562
preempt_schedule_notrace+0xd9/0x120 kernel/sched/core.c:6824
preempt_schedule_notrace_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:35
rcu_is_watching+0x76/0xa0 kernel/rcu/tree.c:722
trace_lock_acquire include/trace/events/lock.h:24 [inline]
lock_acquire+0xe3/0x4a0 kernel/locking/lockdep.c:5633
rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
rcu_read_lock include/linux/rcupdate.h:791 [inline]
freezer_fork+0x12a/0x470 kernel/cgroup/legacy_freezer.c:223
cgroup_post_fork+0x383/0x7c0 kernel/cgroup/cgroup.c:6691
copy_process+0x3cd3/0x4030 kernel/fork.c:2581
kernel_clone+0x24b/0x900 kernel/fork.c:2762
__do_sys_clone3 kernel/fork.c:3061 [inline]
__se_sys_clone3+0x32d/0x3f0 kernel/fork.c:3045
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f65f139d609
RSP: 002b:00007ffe3dcc4fa8 EFLAGS: 00000206 ORIG_RAX: 00000000000001b3
RAX: ffffffffffffffda RBX: 00007f65f1358ba0 RCX: 00007f65f139d609
RDX: 00007f65f1358ba0 RSI: 0000000000000058 RDI: 00007ffe3dcc5000
RBP: 00007f65f21a66c0 R08: 00007f65f21a66c0 R09: 00007ffe3dcc50e7
R10: 0000000000000008 R11: 0000000000000206 R12: ffffffffffffffe8
R13: 000000000000000b R14: 00007ffe3dcc5000 R15: 00007ffe3dcc50e8
task:kworker/u4:14 state:R running task stack:22136 pid:4434 ppid:2 flags:0x00004000
Workqueue: bat_events batadv_nc_worker
Call Trace:
context_switch kernel/sched/core.c:5245 [inline]
__schedule+0x11d1/0x40e0 kernel/sched/core.c:6562
preempt_schedule_irq+0xbb/0x160 kernel/sched/core.c:6874
irqentry_exit+0x63/0x70 kernel/entry/common.c:439
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:lock_acquire+0x225/0x4a0 kernel/locking/lockdep.c:5666
Code: f7 84 24 80 00 00 00 00 02 00 00 43 c6 44 3d 04 f8 0f 85 f0 00 00 00 41 f7 c6 00 02 00 00 74 01 fb 48 c7 44 24 60 0e 36 e0 45 <4b> c7 44 3d 00 00 00 00 00 43 c7 44 3d 08 00 00 00 00 65 48 8b 04
RSP: 0018:ffffc9000485fac0 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 0000000000000000 RCX: 77106bf7690ed900
RDX: 0000000000000000 RSI: ffffffff8a8c2220 RDI: ffffffff8adf0d20
RBP: ffffc9000485fbc8 R08: dffffc0000000000 R09: 1ffffffff215ee48
R10: dffffc0000000000 R11: fffffbfff215ee49 R12: 0000000000000000
R13: 1ffff9200090bf64 R14: 0000000000000246 R15: dffffc0000000000
rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
rcu_read_lock include/linux/rcupdate.h:791 [inline]
batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline]
batadv_nc_worker+0xeb/0x600 net/batman-adv/network-coding.c:719
process_one_work+0x8a2/0x1160 kernel/workqueue.c:2292
worker_thread+0xaa2/0x1270 kernel/workqueue.c:2439
kthread+0x29d/0x330 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
rcu: rcu_preempt kthread starved for 10593 jiffies! g13657 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:28016 pid:16 ppid:2 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5245 [inline]
__schedule+0x11d1/0x40e0 kernel/sched/core.c:6562
schedule+0xb9/0x180 kernel/sched/core.c:6638
schedule_timeout+0x184/0x2d0 kernel/time/timer.c:2168
rcu_gp_fqs_loop+0x303/0x1340 kernel/rcu/tree.c:1706
rcu_gp_kthread+0x99/0x3b0 kernel/rcu/tree.c:1905
kthread+0x29d/0x330 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 PID: 0 Comm: swapper/0 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
RIP: 0010:default_idle+0xb/0x10 arch/x86/kernel/process.c:742
Code: 48 89 df e8 47 c2 9b f7 e9 44 ff ff ff e8 3d 07 f6 ff 00 00 cc cc 00 00 cc cc 00 00 cc cc 00 66 90 0f 00 2d 57 eb 4e 00 fb f4 0f 1f 40 00 41 57 41 56 53 49 be 00 00 00 00 00 fc ff df 65 48
RSP: 0018:ffffffff8c807d88 EFLAGS: 000002c6
RAX: 4a48b95468519100 RBX: ffffffff8a37c257 RCX: 4a48b95468519100
RDX: 0000000000000001 RSI: ffffffff8a8c10a0 RDI: ffffffff8adf0d20
RBP: ffffffff8c807ec0 R08: ffff8880b8e3580b R09: 1ffff110171c6b01
R10: dffffc0000000000 R11: ffffed10171c6b02 R12: 0000000000000000
R13: dffffc0000000000 R14: ffffffff8c8bc740 R15: 1ffffffff1900fbc
FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055556dbad9e8 CR3: 000000005b044000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
default_idle_call+0x84/0xc0 kernel/sched/idle.c:109
cpuidle_idle_call kernel/sched/idle.c:199 [inline]
do_idle+0x250/0x680 kernel/sched/idle.c:323
cpu_startup_entry+0x3f/0x60 kernel/sched/idle.c:422
rest_init+0x2dc/0x300 init/main.c:745
arch_call_rest_init+0xa/0xa init/main.c:905
start_kernel+0x493/0x53c init/main.c:1152
secondary_startup_64_no_verify+0xcf/0xdb