rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P26376/1:b..l P26418/1:b..l
rcu: (detected by 0, t=10502 jiffies, g=132389, q=195 ncpus=2)
task:syz.6.5471 state:R running task stack:26040 pid:26418 tgid:26396 ppid:22494 task_flags:0x400140 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x1139/0x6150 kernel/sched/core.c:6863
preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7190
irqentry_exit+0x1d8/0x8c0 kernel/entry/common.c:216
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:__page_table_check_zero+0x1d8/0x4a0 mm/page_table_check.c:142
Code: e8 1d cd 89 ff 48 39 eb 0f 84 fc 00 00 00 e8 ff d2 89 ff 48 8b 1d 28 3c 28 0c be 04 00 00 00 4c 01 e3 48 89 df e8 08 b0 f3 ff <48> 89 d8 48 c1 e8 03 42 0f b6 14 38 48 89 d8 83 e0 07 83 c0 03 38
RSP: 0018:ffffc9000c507460 EFLAGS: 00000246
RAX: 0000000000000001 RBX: ffff88801e941448 RCX: ffffffff823515c8
RDX: ffffed1003d2828a RSI: 0000000000000004 RDI: ffff88801e941448
RBP: 0000000000000000 R08: 0000000000000000 R09: ffffed1003d28289
R10: ffff88801e94144b R11: ffff8880375d0b30 R12: ffff88801e941400
R13: 0000000000000001 R14: 0000000000000000 R15: dffffc0000000000
page_table_check_free include/linux/page_table_check.h:43 [inline]
free_pages_prepare mm/page_alloc.c:1407 [inline]
free_unref_folios+0xa40/0x1610 mm/page_alloc.c:3000
folios_put_refs+0x4be/0x750 mm/swap.c:1002
folio_batch_release include/linux/pagevec.h:101 [inline]
shmem_undo_range+0x58f/0x1140 mm/shmem.c:1137
shmem_truncate_range mm/shmem.c:1249 [inline]
shmem_evict_inode+0x39e/0xbe0 mm/shmem.c:1379
evict+0x3c2/0xad0 fs/inode.c:837
iput_final fs/inode.c:1951 [inline]
iput.part.0+0x621/0x1190 fs/inode.c:2003
iput+0x35/0x40 fs/inode.c:1966
dentry_unlink_inode+0x29c/0x480 fs/dcache.c:467
__dentry_kill+0x1d0/0x600 fs/dcache.c:670
finish_dput+0x76/0x480 fs/dcache.c:879
dput.part.0+0x451/0x570 fs/dcache.c:928
dput+0x1f/0x30 fs/dcache.c:920
__fput+0x51c/0xb70 fs/file_table.c:476
task_work_run+0x150/0x240 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+0xfb/0x540 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+0x4ee/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f1a9118f749
RSP: 002b:00007f1a92028038 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: 0000200000000000 RBX: 00007f1a913e6090 RCX: 00007f1a9118f749
RDX: 0000000002000003 RSI: 0000000000ff5000 RDI: 0000200000000000
RBP: 00007f1a91213f91 R08: ffffffffffffffff R09: 0000000000000000
R10: 000000000004c831 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f1a913e6128 R14: 00007f1a913e6090 R15: 00007ffc35958588
task:syz.4.5463 state:R running task stack:23544 pid:26376 tgid:26376 ppid:16145 task_flags:0x40064c flags:0x00080001
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x1139/0x6150 kernel/sched/core.c:6863
preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7190
irqentry_exit+0x1d8/0x8c0 kernel/entry/common.c:216
asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
RIP: 0010:rcu_read_lock include/linux/rcupdate.h:867 [inline]
RIP: 0010:class_rcu_constructor include/linux/rcupdate.h:1195 [inline]
RIP: 0010:unwind_next_frame+0xae/0x20b0 arch/x86/kernel/unwind_orc.c:495
Code: 48 89 04 24 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 80 3c 02 00 0f 85 5d 18 00 00 49 8b 45 38 48 89 44 24 10 e8 42 47 36 00 <31> d2 45 31 c9 45 31 c0 48 8d 05 00 00 00 00 50 b9 02 00 00 00 31
RSP: 0018:ffffc9000bf76f38 EFLAGS: 00000293
RAX: 0000000000000001 RBX: 0000000000000001 RCX: ffffc9000bf76efc
RDX: 0000000000000000 RSI: ffffffff821a9a32 RDI: ffff888027128484
RBP: ffffc9000bf76ff0 R08: 0000000000000001 R09: 00000000ffffffff
R10: 0000000000000002 R11: 0000000000013373 R12: ffffffff81a960f0
R13: ffffc9000bf76fa8 R14: 0000000000000000 R15: ffff888027128000
arch_stack_walk+0x94/0x100 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
save_stack+0x160/0x1f0 mm/page_owner.c:165
__reset_page_owner+0x84/0x1a0 mm/page_owner.c:320
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1406 [inline]
free_unref_folios+0xa22/0x1610 mm/page_alloc.c:3000
folios_put_refs+0x4be/0x750 mm/swap.c:1002
folio_batch_release include/linux/pagevec.h:101 [inline]
shmem_undo_range+0x58f/0x1140 mm/shmem.c:1137
shmem_truncate_range mm/shmem.c:1249 [inline]
shmem_evict_inode+0x39e/0xbe0 mm/shmem.c:1379
evict+0x3c2/0xad0 fs/inode.c:837
iput_final fs/inode.c:1951 [inline]
iput.part.0+0x621/0x1190 fs/inode.c:2003
iput+0x35/0x40 fs/inode.c:1966
dentry_unlink_inode+0x29c/0x480 fs/dcache.c:467
__dentry_kill+0x1d0/0x600 fs/dcache.c:670
finish_dput+0x76/0x480 fs/dcache.c:879
dput.part.0+0x451/0x570 fs/dcache.c:928
dput+0x1f/0x30 fs/dcache.c:920
__fput+0x51c/0xb70 fs/file_table.c:476
task_work_run+0x150/0x240 kernel/task_work.c:233
exit_task_work include/linux/task_work.h:40 [inline]
do_exit+0x87f/0x2bd0 kernel/exit.c:971
do_group_exit+0xd3/0x2a0 kernel/exit.c:1112
get_signal+0x2671/0x26d0 kernel/signal.c:3034
arch_do_signal_or_restart+0x8f/0x7e0 arch/x86/kernel/signal.c:337
__exit_to_user_mode_loop kernel/entry/common.c:41 [inline]
exit_to_user_mode_loop kernel/entry/common.c:75 [inline]
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
irqentry_exit_to_user_mode_prepare include/linux/irq-entry-common.h:270 [inline]
irqentry_exit_to_user_mode include/linux/irq-entry-common.h:339 [inline]
irqentry_exit+0x38a/0x8c0 kernel/entry/common.c:196
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618
RIP: 0033:0x7f94a7b8f751
RSP: 002b:fffffffffffffe70 EFLAGS: 00010217
RAX: 0000000000000000 RBX: 00007f94a7de6090 RCX: 00007f94a7b8f749
RDX: 0000000000000000 RSI: fffffffffffffe70 RDI: 0000000000008000
RBP: 00007f94a7c13f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 00007f94a7de6128 R14: 00007f94a7de6090 R15: 00007ffe33ce16a8
rcu: rcu_preempt kthread starved for 10582 jiffies! g132389 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:27792 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x1139/0x6150 kernel/sched/core.c:6863
__schedule_loop kernel/sched/core.c:6945 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:6960
schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x1ea/0xaf0 kernel/rcu/tree.c:2083
rcu_gp_kthread+0x26d/0x380 kernel/rcu/tree.c:2285
kthread+0x3c5/0x780 kernel/kthread.c:463
ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 UID: 0 PID: 26423 Comm: syz.2.5476 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:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:160 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x29/0x50 kernel/locking/spinlock.c:202
Code: 90 f3 0f 1e fa 53 48 8b 74 24 08 48 89 fb 48 83 c7 18 e8 7a 0e 1f f6 48 89 df e8 32 61 1f f6 e8 9d 24 4c f6 fb bf 01 00 00 00 42 64 0f f6 65 8b 05 9b c9 37 08 85 c0 74 06 5b e9 01 4d 00 00
RSP: 0018:ffffc9000c9f7ca0 EFLAGS: 00000202
RAX: 0000000003a9d13b RBX: ffff88802cc88000 RCX: ffffffff81c70a2f
RDX: 0000000000000000 RSI: ffffffff8dace4f3 RDI: 0000000000000001
RBP: ffff88802cc88400 R08: 0000000000000001 R09: 0000000000000001
R10: ffffffff9088b9d7 R11: ffff88802d1254b0 R12: 0000000000000000
R13: 0000000000000021 R14: 0000000000000400 R15: ffff88802cc88000
FS: 00007f32118436c0(0000) GS:ffff8881248f5000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f3211821800 CR3: 000000004ee7e000 CR4: 00000000003526f0
DR0: 0000000000000003 DR1: 00000000000001f8 DR2: 000000000000008e
DR3: 000000000000057a DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
spin_unlock_irq include/linux/spinlock.h:401 [inline]
get_signal+0x1e6a/0x26d0 kernel/signal.c:3037
arch_do_signal_or_restart+0x8f/0x7e0 arch/x86/kernel/signal.c:337
__exit_to_user_mode_loop kernel/entry/common.c:41 [inline]
exit_to_user_mode_loop+0x8c/0x540 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+0x4ee/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f321098f749
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:00007f3211843038 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 00007f3210be6090 RCX: 00007f321098f749
RDX: 0000200000000500 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f3210a13f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f3210be6128 R14: 00007f3210be6090 R15: 00007ffe43470e58