rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P10913/1:b..l
(detected by 1, t=10502 jiffies, g=51837, q=113 ncpus=2)
task:syz.2.1593 state:R running task stack:25856 pid:10913 ppid:4261 flags:0x00004002
Call Trace:
context_switch kernel/sched/core.c:5244 [inline]
__schedule+0x10e9/0x40d0 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_acquire+0x20f/0x490 kernel/locking/lockdep.c:5666
Code: 00 9c 8f 84 24 80 00 00 00 f6 84 24 81 00 00 00 02 0f 85 f5 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 66 43 c7 44 3d 09 00 00 43 c6 44 3d 0b
RSP: 0018:ffffc900032b6f40 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 0000000000000000 RCX: c2e3cab74c6bd100
RDX: 0000000000000000 RSI: ffffffff8a6c1080 RDI: ffffffff8abf0ea0
RBP: ffffc900032b7060 R08: dffffc0000000000 R09: fffffbfff2116e49
R10: fffffbfff2116e49 R11: 1ffffffff2116e48 R12: 0000000000000000
R13: 1ffff92000656df4 R14: 0000000000000246 R15: dffffc0000000000
rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
rcu_read_lock include/linux/rcupdate.h:791 [inline]
page_ext_get+0x3a/0x2a0 mm/page_ext.c:157
__reset_page_owner+0x31/0x1a0 mm/page_owner.c:144
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
__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+0x75b/0x2050 mm/shmem.c:946
shmem_truncate_range mm/shmem.c:1062 [inline]
shmem_evict_inode+0x248/0xa40 mm/shmem.c:1171
evict+0x485/0x870 fs/inode.c:705
__dentry_kill+0x431/0x650 fs/dcache.c:611
dentry_kill+0xb8/0x290 fs/dcache.c:-1
dput+0xfa/0x1d0 fs/dcache.c:918
__fput+0x5e0/0x920 fs/file_table.c:328
task_work_run+0x1ca/0x250 kernel/task_work.c:203
exit_task_work include/linux/task_work.h:39 [inline]
do_exit+0x936/0x2400 kernel/exit.c:871
do_group_exit+0x217/0x2d0 kernel/exit.c:1021
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+0xb1/0x140 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: 0033:0x7fb8a978e969
RSP: 002b:00007fb8aa6bb038 EFLAGS: 00000246 ORIG_RAX: 0000000000000133
RAX: 0000000000000006 RBX: 00007fb8a99b5fa0 RCX: 00007fb8a978e969
RDX: 0000000000000080 RSI: 00002000000bd000 RDI: 0000000000000005
RBP: 00007fb8a9810ab1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fb8a99b5fa0 R15: 00007ffd75e61158
rcu: rcu_preempt kthread starved for 10461 jiffies! g51837 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:27200 pid:16 ppid:2 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5244 [inline]
__schedule+0x10e9/0x40d0 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:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 10931 Comm: syz.1.1597 Not tainted 6.1.135-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025
RIP: 0010:trace_hardirqs_on_prepare+0x2/0x190 kernel/trace/trace_preemptirq.c:29
Code: 49 89 d6 e8 b0 14 4b 00 4c 89 f2 e9 35 ff ff ff 0f 1f 84 00 00 00 00 00 e9 7b 9f 03 00 66 2e 0f 1f 84 00 00 00 00 00 90 41 57 <41> 56 41 54 53 65 8b 05 4a 18 7c 7e 85 c0 74 7b 65 8b 05 8f 51 7b
RSP: 0018:ffffc9000342ff00 EFLAGS: 00000046
RAX: 0000000000000000 RBX: ffffc9000342ff58 RCX: 0000000000080000
RDX: ffffc90004c31000 RSI: 000000000007ffff RDI: 0000000000080000
RBP: ffffc9000342ff48 R08: dffffc0000000000 R09: ffffed100fe08b29
R10: ffffed100fe08b29 R11: 1ffff1100fe08b28 R12: 0000000000000000
R13: 0000000000000000 R14: ffffc9000342ff58 R15: 000000000000000f
FS: 00007f339b0a76c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b31410ff8 CR3: 0000000057c00000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
__exit_to_user_mode kernel/entry/common.c:136 [inline]
syscall_exit_to_user_mode+0x1b/0x40 kernel/entry/common.c:305
do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:87
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f339a1b70a0
Code: 83 c0 16 83 e0 f7 74 12 50 48 8d 3d 2a 26 08 00 e8 f5 8f f8 ff 0f 1f 44 00 00 c3 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 <83> ff 21 74 0b c3 66 2e 0f 1f 84 00 00 00 00 00 55 53 48 89 f3 48
RSP: 002b:00007f339b0a6a78 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 00007f339a3b5fa0 RCX: 00007f339a18e969
RDX: 00007f339b0a6a80 RSI: 00007f339b0a6bb0 RDI: 0000000000000021
RBP: 00007f339a210ab1 R08: 0000000008000f28 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f339a3b5fa0 R15: 00007ffcd4911628