rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5253/1:b..l P4496/1:b..l
(detected by 0, t=10502 jiffies, g=15481, q=41 ncpus=2)
task:udevd state:R running task stack:23808 pid:4496 ppid:3637 flags:0x00004002
Call Trace:
context_switch kernel/sched/core.c:5244 [inline]
__schedule+0x10ec/0x40b0 kernel/sched/core.c:6561
preempt_schedule_irq+0xb1/0x150 kernel/sched/core.c:6873
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_is_held_type+0x13a/0x190 kernel/locking/lockdep.c:5710
Code: 75 40 48 c7 04 24 00 00 00 00 9c 8f 04 24 f7 04 24 00 02 00 00 75 46 41 f7 c5 00 02 00 00 74 01 fb 65 48 8b 04 25 28 00 00 00 <48> 3b 44 24 08 75 3c 89 e8 48 83 c4 10 5b 41 5c 41 5d 41 5e 41 5f
RSP: 0018:ffffc90004c77880 EFLAGS: 00000206
RAX: fbdf1637845e1d00 RBX: ffff8880243b5940 RCX: fbdf1637845e1d00
RDX: ffff8880243b5940 RSI: ffffffff8a8c1680 RDI: ffffffff8adefd20
RBP: 0000000000000000 R08: ffff8880243b5940 R09: 0000000000000002
R10: 0000000000000003 R11: 0000000000000000 R12: 0000000000000002
R13: 0000000000000246 R14: ffff888148d6eb18 R15: ffff8880243b6470
lock_is_held include/linux/lockdep.h:283 [inline]
xa_entry include/linux/xarray.h:1198 [inline]
xas_find+0x577/0xab0 lib/xarray.c:1269
find_get_entry mm/filemap.c:2031 [inline]
find_lock_entries+0x1ac/0xb90 mm/filemap.c:2123
truncate_inode_pages_range+0x16b/0xff0 mm/truncate.c:363
kill_bdev block/bdev.c:76 [inline]
blkdev_flush_mapping+0x12c/0x290 block/bdev.c:664
blkdev_put_whole block/bdev.c:695 [inline]
blkdev_put+0x47f/0x710 block/bdev.c:955
blkdev_close+0x51/0x80 block/fops.c:514
__fput+0x22c/0x920 fs/file_table.c:320
task_work_run+0x1ca/0x250 kernel/task_work.c:203
resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177
exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210
__syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303
do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:87
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7ff0616a7407
RSP: 002b:00007fffcf05a300 EFLAGS: 00000202 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 00007ff061d89880 RCX: 00007ff0616a7407
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000008
RBP: 00007ff061d896e8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000002
R13: 0000557f316d1410 R14: 0000000000000008 R15: 0000557f316cbb20
task:syz.3.229 state:R running task stack:23648 pid:5253 ppid:4271 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5244 [inline]
__schedule+0x10ec/0x40b0 kernel/sched/core.c:6561
preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:6730
preempt_schedule+0xa7/0xb0 kernel/sched/core.c:6754
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+0x98/0xe0 kernel/stacktrace.c:122
save_stack+0xf3/0x1e0 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:1459 [inline]
free_pcp_prepare mm/page_alloc.c:1509 [inline]
free_unref_page_prepare+0x8b4/0x9a0 mm/page_alloc.c:3384
free_unref_page_list+0xbb/0x8e0 mm/page_alloc.c:3525
release_pages+0x1f92/0x2200 mm/swap.c:1035
tlb_batch_pages_flush mm/mmu_gather.c:59 [inline]
tlb_flush_mmu_free mm/mmu_gather.c:254 [inline]
tlb_flush_mmu+0xff/0x210 mm/mmu_gather.c:261
tlb_finish_mmu+0xbd/0x1c0 mm/mmu_gather.c:361
exit_mmap+0x343/0x8e0 mm/mmap.c:3262
__mmput+0x118/0x3c0 kernel/fork.c:1200
exit_mm+0x1e6/0x2c0 kernel/exit.c:565
do_exit+0x8c1/0x2400 kernel/exit.c:867
do_group_exit+0x217/0x2d0 kernel/exit.c:1022
get_signal+0x1272/0x1350 kernel/signal.c:2871
arch_do_signal_or_restart+0xb0/0x1230 arch/x86/kernel/signal.c:871
exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174
exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210
__syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303
do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:87
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f903bb8eec9
RSP: 002b:00007f9039df60e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: 0000000000000001 RBX: 00007f903bde5fa8 RCX: 00007f903bb8eec9
RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007f903bde5fac
RBP: 00007f903bde5fa0 R08: 0030df3fe527fc6c R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f903bde6038 R14: 00007ffd4abeca60 R15: 00007ffd4abecb48
rcu: rcu_preempt kthread starved for 9352 jiffies! g15481 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:27592 pid:16 ppid:2 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5244 [inline]
__schedule+0x10ec/0x40b0 kernel/sched/core.c:6561
schedule+0xb9/0x180 kernel/sched/core.c:6637
schedule_timeout+0x15c/0x280 kernel/time/timer.c:1965
rcu_gp_fqs_loop+0x2f2/0x1310 kernel/rcu/tree.c:1706
rcu_gp_kthread+0x95/0x380 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 08/18/2025
RIP: 0010:default_idle+0xb/0x10 arch/x86/kernel/process.c:742
Code: 48 89 df e8 87 71 af f7 e9 4c ff ff ff e8 ad 07 f6 ff 00 00 cc cc 00 00 cc cc 00 00 cc cc 00 66 90 0f 00 2d 37 13 65 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: e00185d55e83bc00 RBX: ffffffff8a218f77 RCX: e00185d55e83bc00
RDX: 0000000000000001 RSI: ffffffff8a8c0500 RDI: ffffffff8adefd20
RBP: ffffffff8c807ec0 R08: dffffc0000000000 R09: ffffed10171c6afa
R10: ffffed10171c6afa R11: 1ffff110171c6af9 R12: 0000000000000000
R13: dffffc0000000000 R14: ffffffff8c8bc680 R15: 1ffffffff1c3ecf6
FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f9c197646c8 CR3: 000000002ebac000 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:191 [inline]
do_idle+0x1fc/0x570 kernel/sched/idle.c:303
cpu_startup_entry+0x3f/0x60 kernel/sched/idle.c:401
rest_init+0x2dc/0x300 init/main.c:733
arch_call_rest_init+0xa/0xa init/main.c:893
start_kernel+0x490/0x539 init/main.c:1140
secondary_startup_64_no_verify+0xcf/0xdb