rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P10089/1:b..l
rcu: (detected by 1, t=10502 jiffies, g=34485, q=200 ncpus=2)
task:syz.2.985 state:R running task stack:26488 pid:10089 tgid:10087 ppid:5815 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:lock_acquire+0x62/0x330 kernel/locking/lockdep.c:5872
Code: 76 17 12 83 f8 07 0f 87 a2 02 00 00 89 c0 48 0f a3 05 82 fe ed 0e 0f 82 74 02 00 00 8b 35 1a 2f ee 0e 85 f6 0f 85 8d 00 00 00 <48> 8b 44 24 30 65 48 2b 05 99 76 17 12 0f 85 ad 02 00 00 48 83 c4
RSP: 0018:ffffc9000fd5f6f8 EFLAGS: 00000206
RAX: 0000000000000046 RBX: ffffffff8e3c9620 RCX: 000000009662570c
RDX: 0000000000000000 RSI: ffffffff8da9bf6a RDI: ffffffff8bf24280
RBP: 0000000000000002 R08: 0000000089233b82 R09: 00000000289233b8
R10: 0000000000000002 R11: ffff88801d7f0b30 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
rcu_read_lock include/linux/rcupdate.h:867 [inline]
class_rcu_constructor include/linux/rcupdate.h:1195 [inline]
kernfs_root+0x34/0x2a0 fs/kernfs/kernfs-internal.h:75
kernfs_link_sibling+0x537/0x770 fs/kernfs/dir.c:398
kernfs_add_one+0x20a/0x840 fs/kernfs/dir.c:813
__kernfs_create_file+0x295/0x350 fs/kernfs/file.c:1086
sysfs_add_file_mode_ns+0x207/0x3c0 fs/sysfs/file.c:313
create_files fs/sysfs/group.c:82 [inline]
internal_create_group+0x597/0xf70 fs/sysfs/group.c:189
internal_create_groups+0x9d/0x150 fs/sysfs/group.c:229
setup_gid_attrs drivers/infiniband/core/sysfs.c:1162 [inline]
ib_setup_port_attrs+0x41f/0x600 drivers/infiniband/core/sysfs.c:1439
add_one_compat_dev+0x5b3/0x820 drivers/infiniband/core/device.c:1005
rdma_dev_init_net+0x30a/0x590 drivers/infiniband/core/device.c:1221
ops_init+0x1e2/0x5f0 net/core/net_namespace.c:137
setup_net+0x11d/0x3a0 net/core/net_namespace.c:446
copy_net_ns+0x351/0x7c0 net/core/net_namespace.c:581
create_new_namespaces+0x3ea/0xab0 kernel/nsproxy.c:130
unshare_nsproxy_namespaces+0xc0/0x1f0 kernel/nsproxy.c:226
ksys_unshare+0x45b/0xa40 kernel/fork.c:3171
__do_sys_unshare kernel/fork.c:3242 [inline]
__se_sys_unshare kernel/fork.c:3240 [inline]
__x64_sys_unshare+0x31/0x40 kernel/fork.c:3240
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: 0033:0x7f718778f749
RSP: 002b:00007f71886e5038 EFLAGS: 00000246 ORIG_RAX: 0000000000000110
RAX: ffffffffffffffda RBX: 00007f71879e5fa0 RCX: 00007f718778f749
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000000006a040000
RBP: 00007f7187813f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f71879e6038 R14: 00007f71879e5fa0 R15: 00007ffefa7d6428
rcu: rcu_preempt kthread starved for 10538 jiffies! g34485 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1
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:28064 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:
CPU: 1 UID: 0 PID: 0 Comm: swapper/1 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: 06 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 59 13 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:ffffc90000197de8 EFLAGS: 000002c6
RAX: 000000000220762d RBX: 0000000000000001 RCX: ffffffff8b7706d9
RDX: 0000000000000000 RSI: ffffffff8dac200a RDI: ffffffff8bf24280
RBP: ffffed1003b56498 R08: 0000000000000001 R09: ffffed10170a673d
R10: ffff8880b85339eb R11: ffff88801dab2ff0 R12: 0000000000000001
R13: ffff88801dab24c0 R14: ffffffff9087f7d0 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff888124a09000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00002000000015c0 CR3: 000000000e184000 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
start_secondary+0x21d/0x2d0 arch/x86/kernel/smpboot.c:312
common_startup_64+0x13e/0x148