rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P6177/1:b..l P5824/1:b..l
rcu: (detected by 1, t=10502 jiffies, g=11077, q=686 ncpus=2)
task:udevd state:R running task stack:25544 pid:5824 tgid:5824 ppid:5187 task_flags:0x400140 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x1139/0x6150 kernel/sched/core.c:6863
preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7190
irqentry_exit+0x1d8/0x8c0 kernel/entry/common.c:216
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:rcu_is_watching+0x80/0xc0 kernel/rcu/tree.c:752
Code: 89 da 48 c1 ea 03 0f b6 14 02 48 89 d8 83 e0 07 83 c0 03 38 d0 7c 04 84 d2 75 24 8b 03 c1 e8 02 83 e0 01 65 ff 0d 40 50 0f 12 <74> 07 5b 5d c3 cc cc cc cc e8 f2 f6 88 ff 5b 5d e9 9b a3 d7 09 48
RSP: 0018:ffffc900044af520 EFLAGS: 00000286
RAX: 0000000000000001 RBX: ffff8880b85339e8 RCX: 0000000053069e51
RDX: 0000000000000000 RSI: ffffffff8bf2a800 RDI: ffffffff8dd78f28
RBP: 0000000000000001 R08: 00000000526b3c8d R09: 00000000d526b3c8
R10: 0000000000000002 R11: ffff88807e048b30 R12: fffff52000895ec1
R13: ffffc900044af5f8 R14: ffffc900044af5f8 R15: ffffc900044af600
rcu_read_lock include/linux/rcupdate.h:868 [inline]
class_rcu_constructor include/linux/rcupdate.h:1195 [inline]
unwind_next_frame+0xa86/0x20a0 arch/x86/kernel/unwind_orc.c:479
__unwind_start+0x45f/0x7f0 arch/x86/kernel/unwind_orc.c:758
unwind_start arch/x86/include/asm/unwind.h:64 [inline]
arch_stack_walk+0x73/0x100 arch/x86/kernel/stacktrace.c:24
stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
kasan_save_stack+0x33/0x60 mm/kasan/common.c:56
kasan_save_track+0x14/0x30 mm/kasan/common.c:77
poison_kmalloc_redzone mm/kasan/common.c:397 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:414
kasan_kmalloc include/linux/kasan.h:262 [inline]
__do_kmalloc_node mm/slub.c:5657 [inline]
__kmalloc_noprof+0x33d/0x910 mm/slub.c:5669
kmalloc_noprof include/linux/slab.h:961 [inline]
tomoyo_realpath_from_path+0xc2/0x6e0 security/tomoyo/realpath.c:251
tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
tomoyo_path_perm+0x274/0x460 security/tomoyo/file.c:822
security_inode_getattr+0x116/0x290 security/security.c:1869
vfs_getattr fs/stat.c:259 [inline]
vfs_statx_path fs/stat.c:299 [inline]
vfs_statx+0x121/0x3f0 fs/stat.c:356
vfs_fstatat+0x7b/0xf0 fs/stat.c:375
__do_sys_newfstatat+0x97/0x120 fs/stat.c:542
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f02d2e48b0a
RSP: 002b:00007ffd54c8f988 EFLAGS: 00000246 ORIG_RAX: 0000000000000106
RAX: ffffffffffffffda RBX: 000000000000000f RCX: 00007f02d2e48b0a
RDX: 00007ffd54c8f990 RSI: 00007ffd54c8fa60 RDI: 00000000ffffff9c
RBP: 00007ffd54c90aa0 R08: 0000000000000064 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffd54c90ab0
R13: 0000000000000000 R14: 0000000000000008 R15: 0000555e45bb00c0
task:syz.3.58 state:R running task stack:23224 pid:6177 tgid:6177 ppid:5811 task_flags:0x40064c flags:0x00080001
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x1139/0x6150 kernel/sched/core.c:6863
preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7190
irqentry_exit+0x1d8/0x8c0 kernel/entry/common.c:216
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lock_release+0x183/0x2d0 kernel/locking/lockdep.c:5893
Code: 0f c1 05 58 b3 18 12 83 f8 01 0f 85 03 01 00 00 9c 58 f6 c4 02 0f 85 ee 00 00 00 41 f7 c5 00 02 00 00 74 01 fb 48 8b 44 24 10 <65> 48 2b 05 ed 6b 18 12 0f 85 32 01 00 00 48 83 c4 18 5b 41 5c 41
RSP: 0018:ffffc9000c337190 EFLAGS: 00000206
RAX: 94b4dbd1c6807900 RBX: ffffffff8e3c9620 RCX: ffffc9000c33719c
RDX: 0000000000000000 RSI: ffffffff8daa5ce7 RDI: ffffffff8bf2a880
RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: ffff888031382ff0 R12: ffffffff8234ea8e
R13: 0000000000000206 R14: ffff8880313824c0 R15: 0000000000000001
rcu_lock_release include/linux/rcupdate.h:341 [inline]
rcu_read_unlock include/linux/rcupdate.h:897 [inline]
page_ext_put+0x43/0xd0 mm/page_ext.c:552
__reset_page_owner+0x7a/0x1a0 mm/page_owner.c:312
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1395 [inline]
free_unref_folios+0xa22/0x1610 mm/page_alloc.c:3000
folios_put_refs+0x4be/0x750 mm/swap.c:1002
folio_batch_release include/linux/pagevec.h:101 [inline]
shmem_undo_range+0x58f/0x1140 mm/shmem.c:1137
shmem_truncate_range mm/shmem.c:1249 [inline]
shmem_evict_inode+0x39e/0xbe0 mm/shmem.c:1379
evict+0x3c2/0xad0 fs/inode.c:837
iput_final fs/inode.c:1951 [inline]
iput.part.0+0x621/0x1190 fs/inode.c:2003
iput+0x35/0x40 fs/inode.c:1966
dentry_unlink_inode+0x29c/0x480 fs/dcache.c:467
__dentry_kill+0x1d0/0x600 fs/dcache.c:670
finish_dput+0x76/0x480 fs/dcache.c:879
dput.part.0+0x451/0x570 fs/dcache.c:928
dput+0x1f/0x30 fs/dcache.c:920
__fput+0x51c/0xb70 fs/file_table.c:476
task_work_run+0x150/0x240 kernel/task_work.c:233
exit_task_work include/linux/task_work.h:40 [inline]
do_exit+0x87f/0x2bd0 kernel/exit.c:971
do_group_exit+0xd3/0x2a0 kernel/exit.c:1112
get_signal+0x2671/0x26d0 kernel/signal.c:3034
arch_do_signal_or_restart+0x8f/0x7e0 arch/x86/kernel/signal.c:337
__exit_to_user_mode_loop kernel/entry/common.c:41 [inline]
exit_to_user_mode_loop kernel/entry/common.c:75 [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+0x38a/0x8c0 kernel/entry/common.c:196
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618
RIP: 0033:0x3ed2
RSP: 002b:0000200000000278 EFLAGS: 00010217
RAX: 0000000000000000 RBX: 00007fc2261e6180 RCX: 00007fc225f8f749
RDX: 00002000000000c0 RSI: 0000200000000270 RDI: 0000000000040000
RBP: 00007fc226013f91 R08: 0000200000000500 R09: 0000200000000500
R10: 00002000000002c0 R11: 0000000000000206 R12: 0000000000000000
R13: 00007fc2261e6218 R14: 00007fc2261e6180 R15: 00007fff30ebf368
rcu: rcu_preempt kthread starved for 10577 jiffies! g11077 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:28440 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x1139/0x6150 kernel/sched/core.c:6863
__schedule_loop kernel/sched/core.c:6945 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:6960
schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x1ea/0xaf0 kernel/rcu/tree.c:2083
rcu_gp_kthread+0x26d/0x380 kernel/rcu/tree.c:2285
kthread+0x3c5/0x780 kernel/kthread.c:463
ret_from_fork+0x983/0xb10 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:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
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+0xf/0x20 arch/x86/kernel/paravirt.c:82
Code: 16 60 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 13 c9 12 00 fb f4 cc 35 03 00 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90
RSP: 0018:ffffffff8e007df8 EFLAGS: 000002c6
RAX: 0000000000e235bb RBX: 0000000000000000 RCX: ffffffff8b7796d9
RDX: 0000000000000000 RSI: ffffffff8dacbd61 RDI: ffffffff8bf2a880
RBP: fffffbfff1c12f68 R08: 0000000000000001 R09: ffffed101708673d
R10: ffff8880b84339eb R11: ffffffff8e098670 R12: 0000000000000000
R13: ffffffff8e097b40 R14: ffffffff908881d0 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff8881248fa000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b301f5ff8 CR3: 00000000368f2000 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+0x6c/0xb0 kernel/sched/idle.c:122
cpuidle_idle_call kernel/sched/idle.c:191 [inline]
do_idle+0x38d/0x510 kernel/sched/idle.c:332
cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:430
rest_init+0x16b/0x2b0 init/main.c:757
start_kernel+0x3ef/0x4d0 init/main.c:1206
x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:310
x86_64_start_kernel+0x130/0x190 arch/x86/kernel/head64.c:291
common_startup_64+0x13e/0x148