rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P10957/1:b..l
rcu: (detected by 0, t=10502 jiffies, g=65025, q=205 ncpus=2)
task:udevd state:R running task
stack:23256 pid:10957 tgid:10957 ppid:5210 task_flags:0x400140 flags:0x00080001
Call Trace:
context_switch kernel/sched/core.c:5354 [inline]
__schedule+0x165c/0x5520 kernel/sched/core.c:6966
preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7294
irqentry_exit+0x5e4/0x700 kernel/entry/common.c:240
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lock_acquire+0x221/0x350 kernel/locking/lockdep.c:5872
Code: ff ff ff e8 61 02 18 0a f7 44 24 08 00 02 00 00 0f 84 3a ff ff ff 65 48 8b 05 1b 4e 9f 11 48 3b 44 24 58 75 33 fb 48 83 c4 60 <5b> 41 5c 41 5d 41 5e 41 5f 5d e9 80 ee 1a 0a cc 48 8d 3d 98 a2 94
RSP: 0018:ffffc90004037878 EFLAGS: 00000286
RAX: 1d0c63c219673a00 RBX: 0000000000000000 RCX: 0000000000000046
RDX: 000000005a44979c RSI: ffffffff8e37db44 RDI: ffffffff8c2a9260
RBP: ffffffff81776256 R08: ffffffff81776256 R09: ffffffff8e95d260
R10: ffffc900040379d8 R11: ffffffff81b1aa30 R12: 0000000000000002
R13: ffffffff8e95d260 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+0xc3/0x2550 arch/x86/kernel/unwind_orc.c:495
arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:57 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:584
poison_slab_object mm/kasan/common.c:253 [inline]
__kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285
kasan_slab_free include/linux/kasan.h:235 [inline]
slab_free_hook mm/slub.c:2689 [inline]
slab_free mm/slub.c:6242 [inline]
kmem_cache_free+0x182/0x650 mm/slub.c:6369
file_free fs/file_table.c:75 [inline]
__fput+0x6c5/0xa60 fs/file_table.c:486
fput_close_sync+0x11f/0x240 fs/file_table.c:578
__do_sys_close fs/open.c:1507 [inline]
__se_sys_close fs/open.c:1492 [inline]
__x64_sys_close+0x7e/0x110 fs/open.c:1492
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f9de5f15a67
RSP: 002b:00007ffc75a75528 EFLAGS: 00000297
ORIG_RAX: 0000000000000003
RAX: ffffffffffffffda RBX: 000055608bd406d0 RCX: 00007f9de5f15a67
RDX: 00007f9de5fefea0 RSI: 000055608bd4eba0 RDI: 0000000000000008
RBP: 00007f9de5fefff0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000297 R12: 0000000000000000
R13: 000055608bd406d0 R14: 00007ffc75a75590 R15: 00007ffc75a75570
rcu: rcu_preempt kthread starved for 4629 jiffies! g65025 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:27544 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5354 [inline]
__schedule+0x165c/0x5520 kernel/sched/core.c:6966
__schedule_loop kernel/sched/core.c:7049 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7064
schedule_timeout+0x158/0x2c0 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x312/0x11d0 kernel/rcu/tree.c:2095
rcu_gp_kthread+0x9e/0x2b0 kernel/rcu/tree.c:2297
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 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: 12516 Comm: syz.0.944 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
RIP: 0010:csd_lock_wait kernel/smp.c:342 [inline]
RIP: 0010:smp_call_function_many_cond+0xfcf/0x13d0 kernel/smp.c:892
Code: 79 45 8b 2e 44 89 ee 83 e6 01 31 ff e8 5a ff 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 05 fb 0b 00 eb 37 f3 90 <43> 0f b6 04 2c 84 c0 75 10 41 f7 06 01 00 00 00 74 1e e8 ea fa 0b
RSP: 0018:ffffc90004c77440 EFLAGS: 00000293
RAX: ffffffff81ba76a6 RBX: ffff8880b863c108 RCX: ffff888032d43d00
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90004c77580 R08: ffffffff9033bef7 R09: 1ffffffff20677de
R10: dffffc0000000000 R11: fffffbfff20677df R12: 1ffff110170e8161
R13: dffffc0000000000 R14: ffff8880b8740b08 R15: 0000000000000001
FS: 0000000000000000(0000) GS:ffff888125204000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ff312fd5d58 CR3: 000000000e74a000 CR4: 00000000003526f0
Call Trace:
on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1057
__flush_tlb_multi arch/x86/include/asm/paravirt.h:46 [inline]
flush_tlb_multi arch/x86/mm/tlb.c:1361 [inline]
flush_tlb_mm_range+0x5c3/0x10b0 arch/x86/mm/tlb.c:1451
tlb_flush arch/x86/include/asm/tlb.h:23 [inline]
tlb_flush_mmu_tlbonly include/asm-generic/tlb.h:509 [inline]
tlb_flush_mmu+0x1af/0xa30 mm/mmu_gather.c:423
tlb_finish_mmu+0xf9/0x230 mm/mmu_gather.c:549
free_ldt_pgtables+0x19d/0x350 arch/x86/kernel/ldt.c:411
arch_exit_mmap arch/x86/include/asm/mmu_context.h:229 [inline]
exit_mmap+0x1af/0x9e0 mm/mmap.c:1285
__mmput+0x118/0x430 kernel/fork.c:1178
exit_mm+0x18e/0x250 kernel/exit.c:581
do_exit+0x6a2/0x22c0 kernel/exit.c:963
do_group_exit+0x21b/0x2d0 kernel/exit.c:1117
get_signal+0x1284/0x1330 kernel/signal.c:3037
arch_do_signal_or_restart+0xbc/0x830 arch/x86/kernel/signal.c:337
__exit_to_user_mode_loop kernel/entry/common.c:64 [inline]
exit_to_user_mode_loop+0x86/0x480 kernel/entry/common.c:98
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:238 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:269 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:328 [inline]
do_syscall_64+0x33e/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff314d9c819
Code: Unable to access opcode bytes at 0x7ff314d9c7ef.
RSP: 002b:00007ffdeaec9158 EFLAGS: 00000246
ORIG_RAX: 00000000000000ca
RAX: fffffffffffffdfc RBX: 000000000006485a RCX: 00007ff314d9c819
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007ff31501609c
RBP: 0000000000000032 R08: 3fffffffffffffff R09: 0000000000000000
R10: 00007ffdeaec9260 R11: 0000000000000246 R12: 00007ffdeaec9280
R13: 00007ff31501609c R14: 000000000006488c R15: 00007ffdeaec9260