rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P7757/1:b..l
rcu: (detected by 0, t=10502 jiffies, g=21009, q=2086 ncpus=2)
task:syz.0.471 state:R running task stack:23192 pid:7757 tgid:7757 ppid:5807 task_flags:0x40064c flags:0x00080001
Call Trace:
context_switch kernel/sched/core.c:5298 [inline]
__schedule+0xfee/0x6120 kernel/sched/core.c:6911
preempt_schedule_irq+0x50/0x90 kernel/sched/core.c:7238
irqentry_exit+0x17b/0x670 kernel/entry/common.c:239
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:__page_table_check_zero+0xc3/0x410 mm/page_table_check.c:139
Code: 81 86 ff 58 85 ed 0f 85 e0 01 00 00 e8 b6 86 86 ff 48 c7 c0 28 4f 12 8e 48 ba 00 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 <0f> 85 33 03 00 00 48 2b 1d f8 dc 8f 0b 48 c1 fb 06 48 89 df 48 89
RSP: 0018:ffffc9001c0f71d8 EFLAGS: 00000246
RAX: 1ffffffff1c249e5 RBX: ffffea000137d400 RCX: ffffffff828273fa
RDX: dffffc0000000000 RSI: ffffffff8282720a RDI: ffff88801efd0000
RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000000
R13: ffffea000137d400 R14: ffffea000137d434 R15: dffffc0000000000
page_table_check_free include/linux/page_table_check.h:46 [inline]
__free_pages_prepare mm/page_alloc.c:1434 [inline]
free_unref_folios+0xb2c/0x1790 mm/page_alloc.c:3040
folios_put_refs+0x53c/0x840 mm/swap.c:1002
folio_batch_release include/linux/pagevec.h:101 [inline]
shmem_undo_range+0x5e5/0x1570 mm/shmem.c:1149
shmem_truncate_range mm/shmem.c:1277 [inline]
shmem_evict_inode+0x3f3/0xc40 mm/shmem.c:1407
evict+0x3c2/0xad0 fs/inode.c:846
iput_final fs/inode.c:1966 [inline]
iput.part.0+0x605/0xf50 fs/inode.c:2015
iput+0x35/0x40 fs/inode.c:1981
dentry_unlink_inode+0x2a1/0x490 fs/dcache.c:467
__dentry_kill+0x1d0/0x600 fs/dcache.c:670
finish_dput+0x76/0x480 fs/dcache.c:879
dput.part.0+0x456/0x570 fs/dcache.c:928
dput+0x1f/0x30 fs/dcache.c:920
__fput+0x519/0xb40 fs/file_table.c:477
task_work_run+0x150/0x240 kernel/task_work.c:233
exit_task_work include/linux/task_work.h:40 [inline]
do_exit+0x8b8/0x2b60 kernel/exit.c:976
do_group_exit+0xd5/0x2a0 kernel/exit.c:1118
get_signal+0x1ec7/0x21e0 kernel/signal.c:3034
arch_do_signal_or_restart+0x91/0x7a0 arch/x86/kernel/signal.c:337
__exit_to_user_mode_loop kernel/entry/common.c:64 [inline]
exit_to_user_mode_loop kernel/entry/common.c:98 [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+0x1f8/0x670 kernel/entry/common.c:219
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618
RIP: 0033:0x7f5011b9c819
RSP: 002b:00007f5012b06fd8 EFLAGS: 00010206
RAX: 0000000000000000 RBX: 00007f5011e15fa0 RCX: 00007f5011b9c819
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000004000
RBP: 00007f5011c32c91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 00007f5011e16038 R14: 00007f5011e15fa0 R15: 00007fffd617e6f8
rcu: rcu_preempt kthread starved for 1021 jiffies! g21009 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:27832 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5298 [inline]
__schedule+0xfee/0x6120 kernel/sched/core.c:6911
__schedule_loop kernel/sched/core.c:6993 [inline]
schedule+0xdd/0x390 kernel/sched/core.c:7008
schedule_timeout+0x127/0x280 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x1a9/0x900 kernel/rcu/tree.c:2095
rcu_gp_kthread+0x179/0x230 kernel/rcu/tree.c:2297
kthread+0x370/0x450 kernel/kthread.c:436
ret_from_fork+0x754/0xd80 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:
CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:63
Code: 28 81 02 c3 cc cc cc cc 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 23 c1 19 00 fb f4 fc 35 03 00 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90
RSP: 0018:ffffffff8e407e00 EFLAGS: 00000246
RAX: 0000000001255511 RBX: ffffffff8e4975c0 RCX: ffffffff8b91cc75
RDX: 0000000000000000 RSI: ffffffff8de7bd89 RDI: ffffffff8c1b23a0
RBP: 0000000000000000 R08: 0000000000000001 R09: ffffed101708679d
R10: ffff8880b8433ceb R11: 0000000000000000 R12: 0000000000000000
R13: fffffbfff1c92eb8 R14: 0000000000000000 R15: ffffffff90d9e210
FS: 0000000000000000(0000) GS:ffff888124335000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00002000001f8030 CR3: 000000000e598000 CR4: 00000000003526f0
DR0: 0000000000002683 DR1: 0000000000000009 DR2: 0000000000000003
DR3: 0000000000000008 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
arch_safe_halt arch/x86/include/asm/paravirt.h:73 [inline]
default_idle+0x9/0x10 arch/x86/kernel/process.c:767
default_idle_call+0x6c/0xb0 kernel/sched/idle.c:122
cpuidle_idle_call kernel/sched/idle.c:199 [inline]
do_idle+0x464/0x590 kernel/sched/idle.c:352
cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:451
rest_init+0x251/0x260 init/main.c:760
start_kernel+0x47f/0x480 init/main.c:1210
x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310
x86_64_start_kernel+0x12b/0x130 arch/x86/kernel/head64.c:291
common_startup_64+0x13e/0x148