rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 1-...!: (1 GPs behind) idle=89c4/1/0x4000000000000000 softirq=121104/121117 fqs=3
rcu: (detected by 0, t=10502 jiffies, g=141173, q=522 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 22016 Comm: udevd Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
RIP: 0010:lock_acquire+0x2d/0x370 kernel/locking/lockdep.c:5828
Code: fa 41 57 41 56 41 89 f6 41 55 45 89 c5 41 54 41 89 cc 55 48 89 fd 53 89 d3 48 83 ec 38 65 4c 8b 3d 20 bf 7d 12 4c 89 7c 24 30 <4d> 89 cf 66 90 65 8b 05 3b bf 7d 12 83 f8 07 0f 87 da 00 00 00 48
RSP: 0018:ffffc90000a08e10 EFLAGS: 00000082
RAX: 0000000000010001 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff8880b8528418
RBP: ffff8880b8528418 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000001 R14: 0000000000000000 R15: c1a0a41194e4bc00
FS: 00007f6b4413d880(0000) GS:ffff888123eee000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffc0fd96f90 CR3: 0000000054d18000 CR4: 00000000003526f0
Call Trace:
__raw_spin_lock_irq include/linux/spinlock_api_smp.h:142 [inline]
_raw_spin_lock_irq+0x36/0x50 kernel/locking/spinlock.c:174
__run_hrtimer kernel/time/hrtimer.c:2036 [inline]
__hrtimer_run_queues+0x1b7/0x9c0 kernel/time/hrtimer.c:2096
hrtimer_interrupt+0x3e5/0x940 kernel/time/hrtimer.c:2215
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1051 [inline]
__sysvec_apic_timer_interrupt+0x109/0x470 arch/x86/kernel/apic/apic.c:1068
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline]
sysvec_apic_timer_interrupt+0x9e/0xc0 arch/x86/kernel/apic/apic.c:1062
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0010:rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
RIP: 0010:rcu_read_lock include/linux/rcupdate.h:840 [inline]
RIP: 0010:class_rcu_constructor include/linux/rcupdate.h:1183 [inline]
RIP: 0010:unwind_next_frame+0xbd/0x2090 arch/x86/kernel/unwind_orc.c:495
Code: c1 ea 03 80 3c 02 00 0f 85 0c 19 00 00 49 8b 45 38 48 89 44 24 10 e8 12 fc 35 00 31 d2 45 31 c9 45 31 c0 48 8d 05 00 00 00 00 <50> b9 02 00 00 00 31 f6 48 c7 c7 00 61 be 8e e8 ff 8c 2d 00 e8 6a
RSP: 0018:ffffc9000396f518 EFLAGS: 00000246
RAX: ffffffff81b7d3ad RBX: 0000000000000001 RCX: ffffc9000396f4dc
RDX: 0000000000000000 RSI: ffffffff84de29ec RDI: ffff88801c7b4f44
RBP: ffffc9000396f5d0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000200 R11: 000000000003de28 R12: ffffffff81f3dda0
R13: ffffc9000396f588 R14: 0000000000000000 R15: ffff88801c7b4a80
arch_stack_walk+0x94/0xf0 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
kasan_save_track+0x14/0x30 mm/kasan/common.c:78
poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:415
kasan_kmalloc include/linux/kasan.h:263 [inline]
__do_kmalloc_node mm/slub.c:5362 [inline]
__kmalloc_noprof+0x322/0x820 mm/slub.c:5387
_kmalloc_noprof include/linux/slab.h:973 [inline]
_kzalloc_noprof include/linux/slab.h:1290 [inline]
tomoyo_encode2+0xfb/0x3c0 security/tomoyo/realpath.c:45
tomoyo_encode+0x29/0x50 security/tomoyo/realpath.c:80
tomoyo_realpath_from_path+0x18c/0x690 security/tomoyo/realpath.c:283
tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
tomoyo_path_perm+0x276/0x460 security/tomoyo/file.c:827
security_inode_getattr+0x116/0x280 security/security.c:1895
vfs_getattr fs/stat.c:259 [inline]
vfs_statx_path fs/stat.c:299 [inline]
vfs_statx+0x11f/0x3f0 fs/stat.c:356
vfs_fstatat+0x77/0xe0 fs/stat.c:373
__do_sys_newfstatat+0x9d/0x120 fs/stat.c:538
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f6b43b11b0a
Code: 48 8b 15 f1 f2 0d 00 f7 d8 64 89 02 b8 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 41 89 ca b8 06 01 00 00 0f 05 <3d> 00 f0 ff ff 77 07 31 c0 c3 0f 1f 40 00 48 8b 15 b9 f2 0d 00 f7
RSP: 002b:00007ffc0fda74e8 EFLAGS: 00000246 ORIG_RAX: 0000000000000106
RAX: ffffffffffffffda RBX: 00007ffc0fda7980 RCX: 00007f6b43b11b0a
RDX: 00007ffc0fda74f0 RSI: 00007ffc0fda7980 RDI: 00000000ffffff9c
RBP: 00005603bf05e2c0 R08: 0000000000000000 R09: 0000000000000020
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffc0fda7580
R13: 00007ffc0fda7db5 R14: 000056039733eca4 R15: 000056039733ebcc
rcu: rcu_preempt kthread starved for 10496 jiffies! g141173 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:27528 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5510 [inline]
__schedule+0x125c/0x6730 kernel/sched/core.c:7234
__schedule_loop kernel/sched/core.c:7311 [inline]
schedule+0xdd/0x2c0 kernel/sched/core.c:7326
schedule_timeout+0x127/0x280 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x1a9/0x900 kernel/rcu/tree.c:2123
rcu_gp_kthread+0x179/0x230 kernel/rcu/tree.c:2325
kthread+0x370/0x450 kernel/kthread.c:436
ret_from_fork+0x72b/0xd50 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: 22400 Comm: syz.2.4275 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
RIP: 0010:csd_lock_wait kernel/smp.c:342 [inline]
RIP: 0010:smp_call_function_many_cond+0x589/0x16c0 kernel/smp.c:892
Code: b8 00 00 00 00 00 fc ff df 48 8b 54 24 08 49 89 d5 49 89 d4 49 c1 ed 03 41 83 e4 07 49 01 c5 41 83 c4 03 e8 b9 95 0c 00 f3 90 <41> 0f b6 45 00 41 38 c4 7c 08 84 c0 0f 85 2c 0f 00 00 8b 45 08 31
RSP: 0018:ffffc9000324fa80 EFLAGS: 00000246
RAX: 0000000000080000 RBX: 0000000000000001 RCX: ffffc9000f82e000
RDX: 0000000000080000 RSI: ffffffff81fd3ae7 RDI: ffff888030650000
RBP: ffff8880b8541240 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000003
R13: ffffed10170a8249 R14: 0000000000000001 R15: ffff8880b843c880
FS: 00007f76ecbbc6c0(0000) GS:ffff888123dee000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f76ecbbbff8 CR3: 0000000034330000 CR4: 00000000003526f0
Call Trace:
on_each_cpu_cond_mask+0x40/0x90 kernel/smp.c:1057
on_each_cpu include/linux/smp.h:72 [inline]
smp_text_poke_sync_each_cpu arch/x86/kernel/alternative.c:2773 [inline]
smp_text_poke_batch_finish+0x337/0xc60 arch/x86/kernel/alternative.c:2983
arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146
jump_label_update+0x37a/0x550 kernel/jump_label.c:910
static_key_enable_cpuslocked+0x1bc/0x270 kernel/jump_label.c:210
static_key_enable+0x1a/0x20 kernel/jump_label.c:223
__sched_core_enable kernel/sched/core.c:475 [inline]
sched_core_get+0x8a/0xa0 kernel/sched/core.c:499
sched_core_alloc_cookie kernel/sched/core_sched.c:20 [inline]
sched_core_share_pid+0x406/0x9d0 kernel/sched/core_sched.c:187
__do_sys_prctl+0x67b/0x2270 kernel/sys.c:2808
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f76ebd9de59
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f76ecbbc028 EFLAGS: 00000246 ORIG_RAX: 000000000000009d
RAX: ffffffffffffffda RBX: 00007f76ec026090 RCX: 00007f76ebd9de59
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 000000000000003e
RBP: 00007f76ebe33e6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f76ec026128 R14: 00007f76ec026090 R15: 00007ffea50955e8