rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P26144/2:b..l
rcu: (detected by 0, t=10502 jiffies, g=170657, q=668 ncpus=2)
task:syz-executor state:R running task stack:22392 pid:26144 tgid:26144 ppid:26141 task_flags:0x400140 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5290 [inline]
__schedule+0x14db/0x5030 kernel/sched/core.c:6902
preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7229
irqentry_exit+0x5e3/0x670 kernel/entry/common.c:216
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:raw_atomic_fetch_add_unless include/linux/atomic/atomic-arch-fallback.h:2429 [inline]
RIP: 0010:raw_atomic_add_unless include/linux/atomic/atomic-arch-fallback.h:2456 [inline]
RIP: 0010:atomic_add_unless include/linux/atomic/atomic-instrumented.h:1518 [inline]
RIP: 0010:page_ref_add_unless include/linux/page_ref.h:238 [inline]
RIP: 0010:folio_ref_add_unless include/linux/page_ref.h:248 [inline]
RIP: 0010:folio_try_get+0xf2/0x340 include/linux/page_ref.h:264
Code: c7 ff 49 83 c6 34 4c 89 f7 be 04 00 00 00 e8 15 db 2d 00 4c 89 f0 48 c1 e8 03 42 0f b6 04 20 84 c0 0f 85 03 01 00 00 45 8b 3e <31> ff 44 89 fe e8 64 07 c7 ff 45 85 ff 0f 84 e1 00 00 00 41 8d 4f
RSP: 0018:ffffc9000416f4d0 EFLAGS: 00000246
RAX: 0000000000000000 RBX: ffffffff81fa159c RCX: ffffffff81fa165b
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffea000127f0b4
RBP: 0000000000000001 R08: ffffea000127f0b7 R09: 1ffffd400024fe16
R10: dffffc0000000000 R11: fffff9400024fe17 R12: dffffc0000000000
R13: fffffffffffffffe R14: ffffea000127f0b4 R15: 0000000000000001
find_get_entry mm/filemap.c:2076 [inline]
find_lock_entries+0x24f/0xa60 mm/filemap.c:2166
shmem_undo_range+0x254/0x1490 mm/shmem.c:1120
shmem_truncate_range mm/shmem.c:1250 [inline]
shmem_evict_inode+0x26e/0xa70 mm/shmem.c:1380
evict+0x5f4/0xae0 fs/inode.c:837
__dentry_kill+0x209/0x660 fs/dcache.c:670
finish_dput+0xc9/0x480 fs/dcache.c:879
__fput+0x68e/0xa70 fs/file_table.c:476
task_work_run+0x1d4/0x260 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:44 [inline]
exit_to_user_mode_loop+0xef/0x4e0 kernel/entry/common.c:75
__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_work include/linux/entry-common.h:159 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline]
do_syscall_64+0x2c1/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f4ee918e3aa
RSP: 002b:00007ffccac22a60 EFLAGS: 00000293 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 0000000000000003 RCX: 00007f4ee918e3aa
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 00007ffccac22abc R08: 0000000000000000 R09: 00007ffccac227c7
R10: 0000000000000000 R11: 0000000000000293 R12: 000000000000000f
R13: 00000000000927c0 R14: 000000000015e2a1 R15: 00007ffccac22b10
rcu: rcu_preempt kthread starved for 10535 jiffies! g170657 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:27680 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5290 [inline]
__schedule+0x14db/0x5030 kernel/sched/core.c:6902
__schedule_loop kernel/sched/core.c:6984 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6999
schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x301/0x11b0 kernel/rcu/tree.c:2095
rcu_gp_kthread+0x9b/0x2d0 kernel/rcu/tree.c:2297
kthread+0x389/0x480 kernel/kthread.c:467
ret_from_fork+0x510/0xa50 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 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 26771 Comm: syz.4.4649 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:handle_signal arch/x86/kernel/signal.c:279 [inline]
RIP: 0010:arch_do_signal_or_restart+0x6b0/0x7a0 arch/x86/kernel/signal.c:339
Code: e9 1c fc ff ff e8 40 d2 5a 00 48 b8 00 00 00 00 00 fc ff df 41 80 7c 05 00 00 74 09 48 8b 3c 24 e8 45 a8 c1 00 48 8b 44 24 10 <48> 89 43 50 4c 8d a3 80 00 00 00 4c 89 e0 48 c1 e8 03 48 b9 00 00
RSP: 0018:ffffc9000b8f7d80 EFLAGS: 00000246
RAX: 00000000000000ca RBX: ffffc9000b8f7f48 RCX: 0000000000080000
RDX: ffffc90011159000 RSI: 000000000007ffff RDI: 0000000000080000
RBP: ffffc9000b8f7e90 R08: ffff88809aec9e40 R09: 0000000000000004
R10: fffffffffffffe00 R11: 0000000000000002 R12: fffffffffffffe00
R13: 1ffff9200171eff3 R14: ffff88809aec9e40 R15: 0000000010000000
FS: 00007f62f9c566c0(0000) GS:ffff888125cf9000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f62f29ff000 CR3: 00000000648e4000 CR4: 00000000003526f0
Call Trace:
__exit_to_user_mode_loop kernel/entry/common.c:41 [inline]
exit_to_user_mode_loop+0x87/0x4e0 kernel/entry/common.c:75
__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_work include/linux/entry-common.h:159 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline]
do_syscall_64+0x2c1/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f62f8d8f749
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f62f9c560e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007f62f8fe5fa8 RCX: 00007f62f8d8f749
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f62f8fe5fa8
RBP: 00007f62f8fe5fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f62f8fe6038 R14: 00007ffd9c919cd0 R15: 00007ffd9c919db8