rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P3562/1:b..l
(detected by 1, t=10502 jiffies, g=44917, q=65)
task:udevd state:R running task stack:24672 pid: 3562 ppid: 1 flags:0x00004002
Call Trace:
context_switch kernel/sched/core.c:5030 [inline]
__schedule+0x11b8/0x43b0 kernel/sched/core.c:6376
preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:6552
preempt_schedule+0xa7/0xb0 kernel/sched/core.c:6577
preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:34
__raw_spin_unlock include/linux/spinlock_api_smp.h:152 [inline]
_raw_spin_unlock+0x36/0x40 kernel/locking/spinlock.c:186
spin_unlock include/linux/spinlock.h:403 [inline]
fast_dput+0x11e/0x280 fs/dcache.c:-1
dput+0xb7/0x1a0 fs/dcache.c:880
step_into+0x31d/0xd00 fs/namei.c:1815
link_path_walk+0x662/0xd40 fs/namei.c:-1
path_lookupat+0x9d/0x440 fs/namei.c:2454
filename_lookup+0x1e2/0x4f0 fs/namei.c:2484
user_path_at_empty+0x40/0x190 fs/namei.c:2883
do_readlinkat+0xd4/0x480 fs/stat.c:442
__do_sys_readlink fs/stat.c:475 [inline]
__se_sys_readlink fs/stat.c:472 [inline]
__x64_sys_readlink+0x7b/0x90 fs/stat.c:472
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f8940c063a7
RSP: 002b:00007fff1d86f138 EFLAGS: 00000246 ORIG_RAX: 0000000000000059
RAX: ffffffffffffffda RBX: 00007fff1d86f610 RCX: 00007f8940c063a7
RDX: 0000000000000400 RSI: 00007fff1d86f140 RDI: 00007fff1d86f610
RBP: 00007fff1d86f140 R08: 00000000000001e0 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000400
R13: 0000559baa93a100 R14: 0000559bd859c550 R15: 00007fff1d870120
rcu: rcu_preempt kthread timer wakeup didn't happen for 10527 jiffies! g44917 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: Possible timer handling issue on cpu=0 timer-softirq=10977
rcu: rcu_preempt kthread starved for 10528 jiffies! g44917 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:27584 pid: 15 ppid: 2 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5030 [inline]
__schedule+0x11b8/0x43b0 kernel/sched/core.c:6376
schedule+0x11b/0x1e0 kernel/sched/core.c:6459
schedule_timeout+0x15c/0x280 kernel/time/timer.c:1914
rcu_gp_fqs_loop+0x29e/0x11b0 kernel/rcu/tree.c:1972
rcu_gp_kthread+0x98/0x350 kernel/rcu/tree.c:2145
kthread+0x436/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 28098 Comm: syz.2.7422 Not tainted 5.15.189-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:lockdep_hardirqs_on_prepare+0x154/0x760 kernel/locking/lockdep.c:4275
Code: 0d 0c 01 0f 84 9e 03 00 00 65 8b 05 9a b3 a6 7e 85 c0 0f 85 f8 03 00 00 48 89 5c 24 18 65 48 8b 05 11 ad a6 7e 48 89 44 24 10 <48> 8d b8 e0 0a 00 00 48 89 f8 48 c1 e8 03 80 3c 10 00 74 0f e8 93
RSP: 0018:ffffc9000c43e4c0 EFLAGS: 00000046
RAX: ffff888027dbbb80 RBX: 1ffff92001887c9c RCX: ffffffff960bdf03
RDX: dffffc0000000000 RSI: 0000000000000000 RDI: ffffffff814871ba
RBP: ffffc9000c43e580 R08: dffffc0000000000 R09: ffffed1003d739b2
R10: ffffed1003d739b2 R11: 1ffff11003d739b1 R12: ffffffff89558a5e
R13: dffffc0000000000 R14: dffffc0000000000 R15: 1ffff92001887cb4
FS: 00007f6c467066c0(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffead4ded08 CR3: 000000005cbfd000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
trace_hardirqs_on+0x67/0x80 kernel/trace/trace_preemptirq.c:49
__local_bh_enable_ip+0x12a/0x1b0 kernel/softirq.c:406
__raw_spin_trylock_bh include/linux/spinlock_api_smp.h:186 [inline]
_raw_spin_trylock_bh+0x5c/0x70 kernel/locking/spinlock.c:146
spin_trylock_bh include/linux/spinlock.h:423 [inline]
tipc_sk_rcv+0x41e/0x2be0 net/tipc/socket.c:2496
tipc_node_xmit+0x1b9/0xe50 net/tipc/node.c:1703
tipc_node_xmit_skb net/tipc/node.c:1768 [inline]
tipc_node_distr_xmit+0x29a/0x3a0 net/tipc/node.c:1783
tipc_sk_rcv+0x2693/0x2be0 net/tipc/socket.c:2501
tipc_node_xmit+0x1b9/0xe50 net/tipc/node.c:1703
tipc_sk_push_backlog net/tipc/socket.c:1316 [inline]
tipc_sk_filter_connect net/tipc/socket.c:2255 [inline]
tipc_sk_filter_rcv+0x1b30/0x3000 net/tipc/socket.c:2364
tipc_sk_enqueue net/tipc/socket.c:2445 [inline]
tipc_sk_rcv+0x8a2/0x2be0 net/tipc/socket.c:2497
tipc_node_xmit+0x1b9/0xe50 net/tipc/node.c:1703
tipc_node_xmit_skb net/tipc/node.c:1768 [inline]
tipc_node_distr_xmit+0x29a/0x3a0 net/tipc/node.c:1783
tipc_sk_backlog_rcv+0x19e/0x230 net/tipc/socket.c:2412
sk_backlog_rcv include/net/sock.h:1061 [inline]
__release_sock+0x1b9/0x420 net/core/sock.c:2725
release_sock+0x5b/0x1b0 net/core/sock.c:3266
sock_setsockopt+0x1502/0x2270 net/core/sock.c:1379
__sys_setsockopt+0x2f6/0x3d0 net/socket.c:2199
__do_sys_setsockopt net/socket.c:2214 [inline]
__se_sys_setsockopt net/socket.c:2211 [inline]
__x64_sys_setsockopt+0xb1/0xc0 net/socket.c:2211
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f6c47494de9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f6c46706038 EFLAGS: 00000246 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 00007f6c476adfa0 RCX: 00007f6c47494de9
RDX: 0000000000000021 RSI: 0000000000000001 RDI: 0000000000000003
RBP: 00007f6c475162a0 R08: 0000000000000004 R09: 0000000000000000
R10: 0000400000000540 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f6c476adfa0 R15: 00007fff72b5c318