rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5827/1:b..l
rcu: (detected by 1, t=10502 jiffies, g=13797, q=1293 ncpus=2)
task:syz-executor state:R running task stack:19496 pid:5827 tgid:5827 ppid:5819 task_flags:0x400140 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5282 [inline]
__schedule+0x14db/0x5030 kernel/sched/core.c:6894
preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7221
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:debug_lockdep_rcu_enabled+0x2a/0x40 kernel/rcu/update.c:321
Code: f3 0f 1e fa 31 c0 83 3d 93 04 44 04 00 74 1e 83 3d 9a 33 44 04 00 74 15 65 48 8b 0c 25 08 90 a2 92 31 c0 83 b9 04 0b 00 00 00 <0f> 94 c0 e9 8e d8 02 00 cc cc cc cc cc cc cc cc cc cc cc cc cc cc
RSP: 0018:ffffc9000404ef70 EFLAGS: 00000246
RAX: 0000000000000000 RBX: ffffffff90463701 RCX: ffff8880313d8000
RDX: ffffc9000404f001 RSI: dffffc0000000000 RDI: ffffc9000404f050
RBP: dffffc0000000000 R08: ffffc9000404fd78 R09: 0000000000000000
R10: ffffc9000404f098 R11: fffff52000809e15 R12: ffffc9000404fd88
R13: ffffc90004048000 R14: ffffc9000404f048 R15: ffffffff81745df5
rcu_read_unlock include/linux/rcupdate.h:879 [inline]
class_rcu_destructor include/linux/rcupdate.h:1193 [inline]
unwind_next_frame+0x1a64/0x23d0 arch/x86/kernel/unwind_orc.c:695
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:165
__reset_page_owner+0x71/0x1f0 mm/page_owner.c:320
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1436 [inline]
free_unref_folios+0xcc0/0x13e0 mm/page_alloc.c:3033
folios_put_refs+0x584/0x670 mm/swap.c:1002
folio_batch_release include/linux/pagevec.h:101 [inline]
shmem_undo_range+0x49e/0x1490 mm/shmem.c:1138
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
shrink_kill+0xa9/0x2c0 fs/dcache.c:1137
shrink_dentry_list+0x2e0/0x5e0 fs/dcache.c:1164
shrink_dcache_tree+0xca/0x2e0 fs/dcache.c:-1
do_one_tree+0x28/0xe0 fs/dcache.c:1644
shrink_dcache_for_umount+0xa0/0x170 fs/dcache.c:1661
generic_shutdown_super+0x67/0x2c0 fs/super.c:621
kill_anon_super+0x3b/0x70 fs/super.c:1289
deactivate_locked_super+0xbc/0x130 fs/super.c:474
cleanup_mnt+0x425/0x4c0 fs/namespace.c:1323
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: 0033:0x7fed39190a77
RSP: 002b:00007ffd07f488d8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007fed39213d7d RCX: 00007fed39190a77
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffd07f48990
RBP: 00007ffd07f48990 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffd07f49a20
R13: 00007fed39213d7d R14: 000000000001c3cd R15: 00007ffd07f49a60
rcu: rcu_preempt kthread starved for 10556 jiffies! g13797 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:28096 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5282 [inline]
__schedule+0x14db/0x5030 kernel/sched/core.c:6894
__schedule_loop kernel/sched/core.c:6976 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6991
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:246
rcu: Stack dump where RCU GP kthread last ran:
CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:82
Code: cc cc cc cc cc cc cc 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 e3 8f 29 00 f3 0f 1e fa fb f4 cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc90000197e20 EFLAGS: 000002c2
RAX: 000000000014e863 RBX: ffffffff8197762e RCX: 0000000080000001
RDX: 0000000000000001 RSI: ffffffff8d9a7514 RDI: ffffffff8be09d60
RBP: ffffc90000197f10 R08: ffff8880b873375b R09: 1ffff110170e66eb
R10: dffffc0000000000 R11: ffffed10170e66ec R12: ffffffff8fa2daf0
R13: 1ffff11003adcb58 R14: 0000000000000001 R15: 0000000000000001
FS: 0000000000000000(0000) GS:ffff888125cf7000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fecbd8e3a66 CR3: 0000000025b7e000 CR4: 00000000003526f0
Call Trace:
arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline]
default_idle+0x13/0x20 arch/x86/kernel/process.c:767
default_idle_call+0x73/0xb0 kernel/sched/idle.c:122
cpuidle_idle_call kernel/sched/idle.c:191 [inline]
do_idle+0x1be/0x4d0 kernel/sched/idle.c:332
cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:430
start_secondary+0x101/0x110 arch/x86/kernel/smpboot.c:312
common_startup_64+0x13e/0x147