rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 0-...!: (1 GPs behind) idle=4954/1/0x4000000000000000 softirq=41435/41446 fqs=0
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5836/1:b..l
rcu: (detected by 1, t=10502 jiffies, g=30469, q=148 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 9574 Comm: syz.5.1303 Not tainted 6.15.0-syzkaller-12426-ge271ed52b344 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:lockdep_enabled kernel/locking/lockdep.c:124 [inline]
RIP: 0010:lock_release+0x81/0x3e0 kernel/locking/lockdep.c:5884
Code: 84 ad 02 00 00 83 3d 2d ed 02 0e 00 0f 84 44 02 00 00 65 8b 05 30 aa fe 10 85 c0 0f 85 35 02 00 00 65 4c 8b 3c 25 08 b0 9c 92 <41> 83 bf ec 0a 00 00 00 0f 85 1e 02 00 00 49 81 3e 40 73 60 93 0f
RSP: 0018:ffffc90000007bf8 EFLAGS: 00000046
RAX: 0000000000000000 RBX: ffff88807b7d12e8 RCX: 7bea3e63b0e05e00
RDX: 0000000000010000 RSI: ffffffff8be28320 RDI: ffffffff8be282e0
RBP: ffff8880542d0550 R08: ffff8880542d0487 R09: 1ffff1100a85a090
R10: dffffc0000000000 R11: ffffed100a85a091 R12: ffff88807b7d1340
R13: ffffffff89856e9f R14: ffff88807b7d1300 R15: ffff888025923c00
FS: 0000000000000000(0000) GS:ffff888125c55000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b30c1eff8 CR3: 0000000077dbc000 CR4: 0000000000350ef0
Call Trace:
__raw_spin_unlock include/linux/spinlock_api_smp.h:141 [inline]
_raw_spin_unlock+0x16/0x50 kernel/locking/spinlock.c:186
spin_unlock include/linux/spinlock.h:391 [inline]
advance_sched+0x99f/0xc90 net/sched/sch_taprio.c:981
__run_hrtimer kernel/time/hrtimer.c:1761 [inline]
__hrtimer_run_queues+0x52c/0xc60 kernel/time/hrtimer.c:1825
hrtimer_interrupt+0x45b/0xaa0 kernel/time/hrtimer.c:1887
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1039 [inline]
__sysvec_apic_timer_interrupt+0x10b/0x410 arch/x86/kernel/apic/apic.c:1056
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1050
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:lock_release+0x2b5/0x3e0 kernel/locking/lockdep.c:5896
Code: 51 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f7 44 24 20 00 02 00 00 75 56 f7 c3 00 02 00 00 74 01 fb 65 48 8b 05 cb 67 fe 10 <48> 3b 44 24 28 0f 85 8b 00 00 00 48 83 c4 30 5b 41 5c 41 5d 41 5e
RSP: 0018:ffffc9001938f2e8 EFLAGS: 00000206
RAX: 7bea3e63b0e05e00 RBX: 0000000000000202 RCX: 7bea3e63b0e05e00
RDX: 0000000000000003 RSI: ffffffff8db6970d RDI: ffffffff8be28340
RBP: ffff888025924768 R08: ffff88801d61952f R09: 1ffff11003ac32a5
R10: dffffc0000000000 R11: ffffed1003ac32a6 R12: 0000000000000003
R13: 0000000000000003 R14: ffffffff8e13f060 R15: ffff888025923c00
rcu_lock_release include/linux/rcupdate.h:341 [inline]
rcu_read_unlock include/linux/rcupdate.h:871 [inline]
page_table_check_clear+0x4f3/0x700 mm/page_table_check.c:89
ptep_get_and_clear_full arch/x86/include/asm/jump_label.h:-1 [inline]
get_and_clear_full_ptes include/linux/pgtable.h:714 [inline]
zap_present_folio_ptes mm/memory.c:1505 [inline]
zap_present_ptes mm/memory.c:1590 [inline]
do_zap_pte_range mm/memory.c:1691 [inline]
zap_pte_range mm/memory.c:1735 [inline]
zap_pmd_range mm/memory.c:1827 [inline]
zap_pud_range mm/memory.c:1856 [inline]
zap_p4d_range mm/memory.c:1877 [inline]
unmap_page_range+0x3249/0x41c0 mm/memory.c:1898
unmap_single_vma mm/memory.c:1941 [inline]
unmap_vmas+0x399/0x580 mm/memory.c:1985
exit_mmap+0x248/0xb50 mm/mmap.c:1284
__mmput+0x118/0x420 kernel/fork.c:1121
exit_mm+0x1da/0x2c0 kernel/exit.c:581
do_exit+0x640/0x22e0 kernel/exit.c:943
do_group_exit+0x21c/0x2d0 kernel/exit.c:1104
get_signal+0x1286/0x1340 kernel/signal.c:3034
arch_do_signal_or_restart+0x9a/0x750 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop+0x75/0x110 kernel/entry/common.c:111
exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline]
do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fe7f9b8e929
Code: Unable to access opcode bytes at 0x7fe7f9b8e8ff.
RSP: 002b:00007fe7faa230e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: 0000000000000001 RBX: 00007fe7f9db5fa8 RCX: 00007fe7f9b8e929
RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007fe7f9db5fac
RBP: 00007fe7f9db5fa0 R08: 7fffffffffffffff R09: 0000000000000000
R10: ffffffffffffffff R11: 0000000000000246 R12: 00007fe7f9db5fac
R13: 0000000000000000 R14: 00007ffce3745220 R15: 00007ffce3745308
task:syz-executor state:R running task stack:21960 pid:5836 tgid:5836 ppid:5831 task_flags:0x400140 flags:0x00004002
Call Trace:
context_switch kernel/sched/core.c:5396 [inline]
__schedule+0x16f5/0x4d00 kernel/sched/core.c:6785
preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7108
irqentry_exit+0x6f/0x90 kernel/entry/common.c:307
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:lock_acquire+0x175/0x360 kernel/locking/lockdep.c:5875
Code: 00 00 00 00 9c 8f 44 24 30 f7 44 24 30 00 02 00 00 0f 85 cd 00 00 00 f7 44 24 08 00 02 00 00 74 01 fb 65 48 8b 05 3b 7a fe 10 <48> 3b 44 24 58 0f 85 f2 00 00 00 48 83 c4 60 5b 41 5c 41 5d 41 5e
RSP: 0018:ffffc90004e4f0b8 EFLAGS: 00000206
RAX: ddbea81f21d1dc00 RBX: 0000000000000000 RCX: ddbea81f21d1dc00
RDX: 0000000000000001 RSI: ffffffff8db6970d RDI: ffffffff8be28340
RBP: ffffffff81729de5 R08: 0000000000000000 R09: ffffffff81729de5
R10: dffffc0000000000 R11: ffffffff81acf670 R12: 0000000000000002
R13: ffffffff8e13f060 R14: 0000000000000000 R15: 0000000000000246
rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
rcu_read_lock include/linux/rcupdate.h:841 [inline]
class_rcu_constructor include/linux/rcupdate.h:1155 [inline]
unwind_next_frame+0xc2/0x2390 arch/x86/kernel/unwind_orc.c:479
arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
save_stack+0xf5/0x1f0 mm/page_owner.c:156
__reset_page_owner+0x71/0x1f0 mm/page_owner.c:308
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1248 [inline]
free_unref_folios+0xc66/0x14d0 mm/page_alloc.c:2763
folios_put_refs+0x559/0x640 mm/swap.c:992
folio_batch_release include/linux/pagevec.h:101 [inline]
shmem_undo_range+0x49e/0x14b0 mm/shmem.c:1125
shmem_truncate_range mm/shmem.c:1237 [inline]
shmem_evict_inode+0x272/0xa70 mm/shmem.c:1365
evict+0x504/0x9c0 fs/inode.c:810
__dentry_kill+0x209/0x660 fs/dcache.c:669
dput+0x19f/0x2b0 fs/dcache.c:911
__fput+0x68e/0xa70 fs/file_table.c:473
task_work_run+0x1d4/0x260 kernel/task_work.c:227
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop+0xec/0x110 kernel/entry/common.c:114
exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline]
do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fbb4138d58a
RSP: 002b:00007ffc1a489a10 EFLAGS: 00000293 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 0000000000000003 RCX: 00007fbb4138d58a
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 00007ffc1a489a6c R08: 0000000000000000 R09: 00007ffc1a489777
R10: 0000000000000000 R11: 0000000000000293 R12: 00000000000000ed
R13: 00000000000927c0 R14: 000000000003c243 R15: 00007ffc1a489ac0
rcu: rcu_preempt kthread starved for 10502 jiffies! g30469 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:27320 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5396 [inline]
__schedule+0x16f5/0x4d00 kernel/sched/core.c:6785
__schedule_loop kernel/sched/core.c:6863 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6878
schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2054
rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2256
kthread+0x711/0x8a0 kernel/kthread.c:464
ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
rcu: Stack dump where RCU GP kthread last ran:
CPU: 1 UID: 0 PID: 1146 Comm: kworker/u8:6 Not tainted 6.15.0-syzkaller-12426-ge271ed52b344 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:csd_lock_wait kernel/smp.c:340 [inline]
RIP: 0010:smp_call_function_many_cond+0xf6e/0x12d0 kernel/smp.c:885
Code: 89 ee 83 e6 01 31 ff e8 60 78 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 0b 74 0b 00 eb 37 f3 90 43 0f b6 04 2c <84> c0 75 10 41 f7 07 01 00 00 00 74 1e e8 f0 73 0b 00 eb e5 44 89
RSP: 0018:ffffc90003daf6a0 EFLAGS: 00000293
RAX: 0000000000000000 RBX: ffff8880b873cb40 RCX: ffff888026d5bc00
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90003daf800 R08: ffffffff8fa101f7 R09: 1ffffffff1f4203e
R10: dffffc0000000000 R11: fffffbfff1f4203f R12: 1ffff110170c86b5
R13: dffffc0000000000 R14: 0000000000000000 R15: ffff8880b86435a8
FS: 0000000000000000(0000) GS:ffff888125d55000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fe7f9db7bac CR3: 000000000df38000 CR4: 0000000000350ef0
Call Trace:
on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1052
on_each_cpu include/linux/smp.h:71 [inline]
smp_text_poke_sync_each_cpu arch/x86/kernel/alternative.c:2660 [inline]
smp_text_poke_batch_finish+0x5e0/0x1100 arch/x86/kernel/alternative.c:2870
arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146
static_key_enable_cpuslocked+0x128/0x250 kernel/jump_label.c:210
static_key_enable+0x1a/0x20 kernel/jump_label.c:223
toggle_allocation_gate+0xad/0x240 mm/kfence/core.c:850
process_one_work kernel/workqueue.c:3238 [inline]
process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3321
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402
kthread+0x711/0x8a0 kernel/kthread.c:464
ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245