rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P11870/1:b..l P11862/1:b..l
rcu: (detected by 1, t=10502 jiffies, g=70977, q=125 ncpus=2)
task:syz.6.1793 state:R running task stack:25704 pid:11862 ppid:6869 flags:0x00004002
Call Trace:
context_switch kernel/sched/core.c:5381 [inline]
__schedule+0x14e2/0x4580 kernel/sched/core.c:6700
preempt_schedule_irq+0xb5/0x140 kernel/sched/core.c:7010
irqentry_exit+0x67/0x70 kernel/entry/common.c:438
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
RIP: 0010:bytes_is_nonzero mm/kasan/generic.c:84 [inline]
RIP: 0010:memory_is_nonzero mm/kasan/generic.c:102 [inline]
RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:127 [inline]
RIP: 0010:memory_is_poisoned mm/kasan/generic.c:159 [inline]
RIP: 0010:check_region_inline mm/kasan/generic.c:178 [inline]
RIP: 0010:kasan_check_range+0x73/0x290 mm/kasan/generic.c:187
Code: ff df 4f 8d 1c 17 49 ff c8 4d 89 c1 49 c1 e9 03 48 bb 01 00 00 00 00 fc ff df 4d 8d 34 19 4d 89 f4 4d 29 dc 49 83 fc 10 7f 29 <4d> 85 e4 0f 84 41 01 00 00 4c 89 cb 48 f7 d3 4c 01 fb 41 80 3b 00
RSP: 0018:ffffc9000c237268 EFLAGS: 00000283
RAX: ffffffff81b52901 RBX: dffffc0000000001 RCX: ffffffff81b5295c
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffea00017153c0
RBP: ffffc9000c2373d0 R08: ffffea00017153c7 R09: 1ffffd40002e2a78
R10: dffffc0000000000 R11: fffff940002e2a78 R12: 0000000000000001
R13: 1ffffd40002e2a7e R14: fffff940002e2a79 R15: 1ffffd40002e2a78
instrument_atomic_read include/linux/instrumented.h:68 [inline]
_test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline]
folio_test_writeback include/linux/page-flags.h:533 [inline]
find_lock_entries+0x61c/0xfe0 mm/filemap.c:2123
shmem_undo_range+0x254/0x1a40 mm/shmem.c:1009
shmem_truncate_range mm/shmem.c:1136 [inline]
shmem_evict_inode+0x273/0xa70 mm/shmem.c:1265
evict+0x486/0x870 fs/inode.c:705
__dentry_kill+0x431/0x650 fs/dcache.c:611
dentry_kill+0xb8/0x290 fs/dcache.c:-1
dput+0xfe/0x1e0 fs/dcache.c:918
__fput+0x5e5/0x970 fs/file_table.c:392
task_work_run+0x1ce/0x250 kernel/task_work.c:239
exit_task_work include/linux/task_work.h:43 [inline]
do_exit+0x903/0x23c0 kernel/exit.c:874
do_group_exit+0x21b/0x2d0 kernel/exit.c:1023
get_signal+0x12fc/0x1400 kernel/signal.c:2902
arch_do_signal_or_restart+0x96/0x780 arch/x86/kernel/signal.c:310
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:291 [inline]
syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302
do_syscall_64+0x61/0xb0 arch/x86/entry/common.c:87
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f2e10f8e929
RSP: 002b:00007f2e11d860e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007f2e111b6088 RCX: 00007f2e10f8e929
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f2e111b6088
RBP: 00007f2e111b6080 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f2e111b608c
R13: 0000000000000000 R14: 00007fffa983d490 R15: 00007fffa983d578
task:syz.3.1785 state:R running task stack:23816 pid:11870 ppid:9269 flags:0x00004006
Call Trace:
rcu: rcu_preempt kthread starved for 10548 jiffies! g70977 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:27048 pid:17 ppid:2 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5381 [inline]
__schedule+0x14e2/0x4580 kernel/sched/core.c:6700
schedule+0xbd/0x170 kernel/sched/core.c:6774
schedule_timeout+0x160/0x280 kernel/time/timer.c:2167
rcu_gp_fqs_loop+0x302/0x1560 kernel/rcu/tree.c:1663
rcu_gp_kthread+0x99/0x380 kernel/rcu/tree.c:1862
kthread+0x2fa/0x390 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
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: 3517 Comm: kworker/u4:11 Not tainted 6.6.93-syzkaller #0
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:311 [inline]
RIP: 0010:smp_call_function_many_cond+0xde4/0x1130 kernel/smp.c:855
Code: 89 ee 83 e6 01 31 ff e8 1a e7 0a 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 55 e3 0a 00 eb 38 f3 90 42 0f b6 04 2b <84> c0 75 11 41 f7 04 24 01 00 00 00 74 1e e8 39 e3 0a 00 eb e4 44
RSP: 0018:ffffc9000cae7780 EFLAGS: 00000293
RAX: 0000000000000000 RBX: 1ffff110171e82f5 RCX: ffff88802e1d9e00
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc9000cae7900 R08: ffffffff90d84527 R09: 1ffffffff21b08a4
R10: dffffc0000000000 R11: fffffbfff21b08a5 R12: ffff8880b8f417a8
R13: dffffc0000000000 R14: ffff8880b8e3d588 R15: 0000000000000001
FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00002000000012a0 CR3: 000000000cb30000 CR4: 00000000003506f0
Call Trace:
on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1023
on_each_cpu include/linux/smp.h:71 [inline]
text_poke_sync arch/x86/kernel/alternative.c:2222 [inline]
text_poke_bp_batch+0x318/0x930 arch/x86/kernel/alternative.c:2432
text_poke_flush arch/x86/kernel/alternative.c:2623 [inline]
text_poke_finish+0x30/0x50 arch/x86/kernel/alternative.c:2630
arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146
static_key_enable_cpuslocked+0x123/0x240 kernel/jump_label.c:207
static_key_enable+0x1a/0x20 kernel/jump_label.c:220
toggle_allocation_gate+0xaa/0x250 mm/kfence/core.c:831
process_one_work kernel/workqueue.c:2634 [inline]
process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711
worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792
kthread+0x2fa/0x390 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293