rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5817/1:b..l P5194/1:b..l
rcu: (detected by 0, t=10502 jiffies, g=11701, q=737 ncpus=2)
task:udevd state:R running task stack:23288 pid:5194 tgid:5194 ppid:1 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:hlist_bl_first_rcu include/linux/rculist_bl.h:24 [inline]
RIP: 0010:__d_lookup+0x10d/0x780 fs/dcache.c:2437
Code: 05 65 1f 4c 0d 01 48 c7 c7 a0 02 9a 8b be 54 03 00 00 48 c7 c2 e0 02 9a 8b e8 af ee 5d ff 49 89 de 49 c1 ee 03 43 80 3c 26 00 <74> 08 48 89 df e8 a9 44 e7 ff 4c 8b 3b e8 61 2a 1e 09 89 c5 31 ff
RSP: 0018:ffffc90002f57848 EFLAGS: 00000246
RAX: ffffffff8240ac89 RBX: ffffc900009c4f38 RCX: ffff88807e73bc80
RDX: 0000000000000000 RSI: ffffffff8be09d40 RDI: ffffffff8be09d00
RBP: 0000000000000001 R08: ffffffff8240ac46 R09: ffffffff8e144f60
R10: 0000000000002e2e R11: 0000000000000000 R12: dffffc0000000000
R13: ffffffff8240ac46 R14: 1ffff920001389e7 R15: 1ffff920005eaf57
lookup_fast+0x84/0x5b0 fs/namei.c:1874
walk_component fs/namei.c:2275 [inline]
lookup_last fs/namei.c:2780 [inline]
path_lookupat+0x209/0x8c0 fs/namei.c:2804
filename_lookup+0x212/0x570 fs/namei.c:2833
vfs_statx+0xf8/0x550 fs/stat.c:353
vfs_fstatat+0x11b/0x170 fs/stat.c:373
__do_sys_newfstatat fs/stat.c:538 [inline]
__se_sys_newfstatat fs/stat.c:532 [inline]
__x64_sys_newfstatat+0x116/0x190 fs/stat.c:532
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f9d1a111b0a
RSP: 002b:00007ffeaf0a8e08 EFLAGS: 00000246 ORIG_RAX: 0000000000000106
RAX: ffffffffffffffda RBX: 00007ffeaf0a92a0 RCX: 00007f9d1a111b0a
RDX: 00007ffeaf0a8e10 RSI: 00007ffeaf0a92a0 RDI: 00000000ffffff9c
RBP: 000055dc57771910 R08: 0000000000000000 R09: 0000000000000001
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffeaf0a8ea0
R13: 0000000000000100 R14: 000055dc30f3bbe0 R15: 00007ffeaf0a9920
task:syz-executor state:R running task stack:19488 pid:5817 tgid:5817 ppid:5813 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_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:orc_ip arch/x86/kernel/unwind_orc.c:81 [inline]
RIP: 0010:__orc_find arch/x86/kernel/unwind_orc.c:103 [inline]
RIP: 0010:orc_find arch/x86/kernel/unwind_orc.c:238 [inline]
RIP: 0010:unwind_next_frame+0x513/0x23d0 arch/x86/kernel/unwind_orc.c:510
Code: c1 e8 3f 48 01 c8 48 83 e0 fe 4c 8d 3c 45 00 00 00 00 49 01 ef 4c 89 f8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df 0f b6 04 08 <84> c0 75 27 49 63 07 4c 01 f8 49 8d 4f 04 4c 39 e0 48 0f 46 e9 49
RSP: 0018:ffffc9000415f138 EFLAGS: 00000a07
RAX: 0000000000000000 RBX: ffffffff8fc56f6c RCX: dffffc0000000000
RDX: ffffffff8fc56f6c RSI: ffffffff9047014c RDI: ffffffff8be09d00
RBP: ffffffff8fc56f6c R08: 0000000000000001 R09: ffffffff8e144f60
R10: ffffc9000415f258 R11: ffffffff81ad0f00 R12: ffffffff82422a73
R13: ffffffff8fc56f6c R14: ffffc9000415f208 R15: ffffffff8fc56f6c
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
finish_dput+0xc9/0x480 fs/dcache.c:879
__fput+0x68e/0xa70 fs/file_table.c:476
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: 0033:0x7f506798e3aa
RSP: 002b:00007ffd6fb69660 EFLAGS: 00000293 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 0000000000000003 RCX: 00007f506798e3aa
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 00007ffd6fb696bc R08: 0000000000000000 R09: 00007ffd6fb693c7
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000008
R13: 00000000000927c0 R14: 0000000000015f00 R15: 00007ffd6fb69710
rcu: rcu_preempt kthread starved for 10578 jiffies! g11701 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: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: 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 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:ffffffff8de07dc0 EFLAGS: 000002c2
RAX: 00000000013d1609 RBX: ffffffff8197762e RCX: 0000000080000001
RDX: 0000000000000001 RSI: ffffffff8d9a7514 RDI: ffffffff8be09d60
RBP: ffffffff8de07eb0 R08: ffff8880b863375b R09: 1ffff110170c66eb
R10: dffffc0000000000 R11: ffffed10170c66ec R12: ffffffff8fa2daf0
R13: 1ffffffff1bd29d0 R14: 0000000000000000 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff888125bf7000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f6368682f98 CR3: 0000000078a58000 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
rest_init+0x2de/0x300 init/main.c:759
start_kernel+0x386/0x3d0 init/main.c:1209
x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310
x86_64_start_kernel+0x143/0x1c0 arch/x86/kernel/head64.c:291
common_startup_64+0x13e/0x147