rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5192/1:b..l P10919/1:b..l P9686/1:b..l
rcu: (detected by 0, t=10502 jiffies, g=43737, q=694 ncpus=2)
task:udevd state:R running task stack:23536 pid:9686 tgid:9686 ppid:5192 task_flags:0x400140 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5282 [inline]
__schedule+0x14ed/0x5040 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:unwind_next_frame+0xe9f/0x23d0 arch/x86/kernel/unwind_orc.c:607
Code: b3 00 49 89 1f 48 8b 44 24 58 80 3c 28 00 48 8b 5c 24 78 4c 8b 64 24 48 74 08 48 89 df e8 19 81 b3 00 48 8b 44 24 18 48 89 03 10 00 00 00 4c 89 e7 31 f6 e8 e2 82 b3 00 48 8b 14 24 e9 ca 04
RSP: 0018:ffffc9000419f118 EFLAGS: 00000246
RAX: ffffc9000419fd20 RBX: ffffc9000419f220 RCX: 1ffff92000833e01
RDX: ffffffff90462500 RSI: 0000000000000002 RDI: ffffc9000419fd18
RBP: dffffc0000000000 R08: 0000000000000001 R09: ffffffff8e13efa0
R10: ffffc9000419f238 R11: ffffffff81acb2b0 R12: ffffc9000419f238
R13: 1ffff92000833e3f R14: ffffc9000419f1e8 R15: ffffc9000419f230
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:1137
shmem_truncate_range mm/shmem.c:1249 [inline]
shmem_evict_inode+0x26e/0xa70 mm/shmem.c:1379
evict+0x5f4/0xae0 fs/inode.c:837
__dentry_kill+0x209/0x660 fs/dcache.c:670
finish_dput+0xc9/0x480 fs/dcache.c:879
end_renaming fs/namei.c:4059 [inline]
do_renameat2+0x5cd/0x950 fs/namei.c:6122
__do_sys_rename fs/namei.c:6163 [inline]
__se_sys_rename fs/namei.c:6161 [inline]
__x64_sys_rename+0x82/0x90 fs/namei.c:6161
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: 0033:0x7f6ac2a7acc7
RSP: 002b:00007fffa9420328 EFLAGS: 00000206 ORIG_RAX: 0000000000000052
RAX: ffffffffffffffda RBX: 00005624a17b9280 RCX: 00007f6ac2a7acc7
RDX: 00005624a17b1010 RSI: 00007fffa9420340 RDI: 00007fffa9420740
RBP: 00005624a17c9e00 R08: 00000000000001e0 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 00007fffa9420340
R13: 00007fffa9420740 R14: 0000000000000000 R15: 0000562492c2f9dd
task:syz.1.660 state:R running task stack:24584 pid:10919 tgid:10918 ppid:10501 task_flags:0x400140 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5282 [inline]
__schedule+0x14ed/0x5040 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:lock_acquire+0x222/0x340 kernel/locking/lockdep.c:5872
Code: ff ff ff e8 60 9c bf 09 f7 44 24 08 00 02 00 00 0f 84 3a ff ff ff 65 48 8b 05 7a 9a 03 11 48 3b 44 24 58 75 33 fb 48 83 c4 60 <5b> 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc cc 48 8d 3d 97 ad 07
RSP: 0018:ffffc90003ecf0f8 EFLAGS: 00000282
RAX: 30f5edbf958f0a00 RBX: 0000000000000000 RCX: 0000000000000046
RDX: 000000005a44979c RSI: ffffffff8db845c0 RDI: ffffffff8be08c60
RBP: ffffffff8173fd75 R08: ffffffff8173fd75 R09: ffffffff8e13efa0
R10: ffffc90003ecf258 R11: ffffffff81acb2b0 R12: 0000000000000002
R13: ffffffff8e13efa0 R14: 0000000000000000 R15: 0000000000000246
rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
rcu_read_lock include/linux/rcupdate.h:850 [inline]
class_rcu_constructor include/linux/rcupdate.h:1193 [inline]
unwind_next_frame+0xc2/0x23d0 arch/x86/kernel/unwind_orc.c:495
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:1137
shmem_truncate_range mm/shmem.c:1249 [inline]
shmem_evict_inode+0x26e/0xa70 mm/shmem.c:1379
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: 0033:0x7fbd7fd8e3aa
RSP: 002b:00007fbd80ca1e50 EFLAGS: 00000293 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: ffffffffffffffff RCX: 00007fbd7fd8e3aa
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000006
RBP: 0000000000000006 R08: 0000000000000000 R09: 0000000000100028
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000016
R13: 00007fbd80ca1eb0 R14: 0000000000005514 R15: 0000200000000100
task:udevd state:R running task stack:23864 pid:5192 tgid:5192 ppid:1 task_flags:0x400140 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5282 [inline]
__schedule+0x14ed/0x5040 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:lock_release+0x5/0x3b0 kernel/locking/lockdep.c:5876
Code: 00 e9 70 fe ff ff 41 be 2f 00 00 00 e9 0e ff ff ff 0f 1f 40 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 55 <41> 57 41 56 41 55 41 54 53 48 83 ec 30 49 89 f5 49 89 fe 65 48 8b
RSP: 0018:ffffc90002fd7c68 EFLAGS: 00000293
RAX: ffffffff8264f597 RBX: ffffffff8264f45c RCX: ffff88807d85dac0
RDX: 0000000000000000 RSI: ffffffff8264f45c RDI: ffffffff8e13efa0
RBP: 0000000000000001 R08: ffffffff8264f45c R09: ffffffff8e13efa0
R10: dffffc0000000000 R11: ffffed10049a8001 R12: dffffc0000000000
R13: ffff888140ea00f0 R14: ffff88801cef0000 R15: ffff888140ea0000
rcu_lock_release include/linux/rcupdate.h:322 [inline]
rcu_read_unlock include/linux/rcupdate.h:881 [inline]
class_rcu_destructor include/linux/rcupdate.h:1193 [inline]
kernfs_root+0x1e5/0x230 fs/kernfs/kernfs-internal.h:80
kernfs_root_is_locked fs/kernfs/kernfs-internal.h:109 [inline]
kernfs_parent+0x51/0x190 fs/kernfs/kernfs-internal.h:133
kernfs_get_target_path fs/kernfs/symlink.c:67 [inline]
kernfs_getlink fs/kernfs/symlink.c:122 [inline]
kernfs_iop_get_link+0x139/0x6c0 fs/kernfs/symlink.c:140
vfs_readlink+0x24d/0x550 fs/namei.c:6213
do_readlinkat+0x215/0x500 fs/stat.c:590
__do_sys_readlink fs/stat.c:613 [inline]
__se_sys_readlink fs/stat.c:610 [inline]
__x64_sys_readlink+0x7f/0x90 fs/stat.c:610
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: 0033:0x7f6ac2b153a7
RSP: 002b:00007fffa941f1e8 EFLAGS: 00000246 ORIG_RAX: 0000000000000059
RAX: ffffffffffffffda RBX: 00007fffa941f6c0 RCX: 00007f6ac2b153a7
RDX: 0000000000000400 RSI: 00007fffa941f1f0 RDI: 00007fffa941f6c0
RBP: 00007fffa941f1f0 R08: 0000000000000075 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000400
R13: 0000562492c46100 R14: 0000000000000007 R15: 00007fffa9420fc0
rcu: rcu_preempt kthread starved for 10581 jiffies! g43737 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:27904 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5282 [inline]
__schedule+0x14ed/0x5040 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 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
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 43 be 2a 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: 00000000006177ef RBX: ffffffff8197161e RCX: 0000000080000001
RDX: 0000000000000001 RSI: ffffffff8d9a0b7f RDI: ffffffff8be08c60
RBP: ffffffff8de07eb0 R08: ffff8880b863375b R09: 1ffff110170c66eb
R10: dffffc0000000000 R11: ffffed10170c66ec R12: ffffffff8fa25d70
R13: 1ffffffff1bd29b8 R14: 0000000000000000 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff888125c07000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c466040 CR3: 000000001faf6000 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:757
start_kernel+0x386/0x3d0 init/main.c:1207
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