rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P3637/1:b..l
(detected by 0, t=10503 jiffies, g=10773, q=125 ncpus=2)
task:udevd state:R running task stack:25168 pid:3637 ppid:1 flags:0x00004002
Call Trace:
context_switch kernel/sched/core.c:5245 [inline]
__schedule+0x11d1/0x40e0 kernel/sched/core.c:6562
preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:6731
preempt_schedule+0xbc/0xd0 kernel/sched/core.c:6755
preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:34
__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
_raw_spin_unlock_irqrestore+0x10d/0x120 kernel/locking/spinlock.c:194
spin_unlock_irqrestore include/linux/spinlock.h:406 [inline]
__wake_up_common_lock kernel/sched/wait.c:140 [inline]
__wake_up_sync_key+0x128/0x190 kernel/sched/wait.c:208
sock_def_readable+0x15b/0x280 net/core/sock.c:3316
__netlink_sendskb net/netlink/af_netlink.c:1264 [inline]
netlink_sendskb+0x97/0x130 net/netlink/af_netlink.c:1270
netlink_sendmsg+0x8ad/0xbd0 net/netlink/af_netlink.c:1872
sock_sendmsg_nosec net/socket.c:718 [inline]
__sock_sendmsg net/socket.c:730 [inline]
____sys_sendmsg+0x5be/0x970 net/socket.c:2518
___sys_sendmsg+0x2a2/0x360 net/socket.c:2572
__sys_sendmsg net/socket.c:2601 [inline]
__do_sys_sendmsg net/socket.c:2610 [inline]
__se_sys_sendmsg+0x1bb/0x2a0 net/socket.c:2608
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7ffbc42a7407
RSP: 002b:00007ffd1bdc87d0 EFLAGS: 00000202 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007ffbc49b3880 RCX: 00007ffbc42a7407
RDX: 0000000000000000 RSI: 00007ffd1bdc8830 RDI: 0000000000000004
RBP: 00005588e3d632f0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 00000000000000b3
R13: 00005588e3d399e0 R14: 0000000000000000 R15: 0000000000000000
rcu: rcu_preempt kthread starved for 10529 jiffies! g10773 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:26864 pid:16 ppid:2 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5245 [inline]
__schedule+0x11d1/0x40e0 kernel/sched/core.c:6562
preempt_schedule_irq+0xbb/0x160 kernel/sched/core.c:6874
irqentry_exit+0x63/0x70 kernel/entry/common.c:439
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:instrument_atomic_read include/linux/instrumented.h:72 [inline]
RIP: 0010:_test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline]
RIP: 0010:test_ti_thread_flag include/linux/thread_info.h:118 [inline]
RIP: 0010:need_resched include/linux/sched.h:2230 [inline]
RIP: 0010:schedule+0xc3/0x180 kernel/sched/core.c:6640
Code: 49 c1 ee 03 eb 09 48 f7 03 08 00 00 00 74 39 bf 01 00 00 00 e8 ae 89 22 f7 31 ff e8 67 be ff ff bf 01 00 00 00 e8 2d 8b 22 f7 <48> 89 df be 08 00 00 00 e8 70 20 9d f7 43 80 3c 3e 00 74 c8 48 89
RSP: 0018:ffffc90000157ba0 EFLAGS: 00000257
RAX: 0000000000000001 RBX: ffff88813fef5940 RCX: 0000000000000000
RDX: dffffc0000000000 RSI: ffffffff8a8c10a0 RDI: 00000000ffffffff
RBP: ffffc90000157cb0 R08: ffff8880b8e3ab03 R09: 1ffff110171c7560
R10: dffffc0000000000 R11: ffffed10171c7561 R12: 1ffff9200002af78
R13: ffffc90000157be0 R14: 1ffff11027fdeb28 R15: dffffc0000000000
schedule_timeout+0x184/0x2d0 kernel/time/timer.c:2168
rcu_gp_fqs_loop+0x303/0x1340 kernel/rcu/tree.c:1706
rcu_gp_kthread+0x99/0x3b0 kernel/rcu/tree.c:1905
kthread+0x29d/0x330 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 PID: 4466 Comm: syz.3.20 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
RIP: 0010:futex_wait+0xc0/0x5e0 kernel/futex/waitwake.c:634
Code: 33 08 49 8d 85 fa f9 ff ff 4a 89 44 33 10 4e 89 6c 33 18 42 c7 44 33 20 f3 f3 f3 f3 e8 79 33 0b 00 4a c7 44 33 04 00 00 00 00 <42> c6 44 33 0c 00 4a c7 44 33 12 00 00 00 00 42 c7 44 33 1a 00 00
RSP: 0018:ffffc900035e7b60 EFLAGS: 00000293
RAX: ffffffff81774117 RBX: 1ffff920006bcf78 RCX: ffff888024b70000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00007f8c2aa15fa8
RBP: ffffc900035e7d30 R08: 00000000ffffffff R09: 000000000000000d
R10: 000000000000000d R11: 0000000000000000 R12: 00000000ffffffff
R13: f8f8f8f8f8f8f8f8 R14: dffffc0000000000 R15: ffffc900035e7c50
FS: 00007f8c2b6fc6c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000000058 CR3: 000000002f680000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
do_futex+0x310/0x320 kernel/futex/syscalls.c:134
__do_sys_futex kernel/futex/syscalls.c:211 [inline]
__se_sys_futex+0x381/0x410 kernel/futex/syscalls.c:192
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f8c2a79c819
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:00007f8c2b6fc0e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: ffffffffffffffda RBX: 00007f8c2aa15fa8 RCX: 00007f8c2a79c819
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f8c2aa15fa8
RBP: 00007f8c2aa15fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f8c2aa16038 R14: 00007ffef06067f0 R15: 00007ffef06068d8