rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 0-...!: (1 GPs behind) idle=70e4/0/0x1 softirq=193106/193107 fqs=3
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P24672/1:b..l
rcu: (detected by 1, t=10502 jiffies, g=188857, q=166 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/10/2026
RIP: 0010:rcu_is_watching_curr_cpu include/linux/context_tracking.h:128 [inline]
RIP: 0010:rcu_is_watching+0x2c/0xc0 kernel/rcu/tree.c:752
Code: 1e fa 55 53 65 ff 05 f3 7d 46 12 e8 fe 68 af 09 48 c7 c3 68 3c 35 94 89 c5 83 f8 07 0f 87 82 00 00 00 48 8d 3c ed 20 79 41 8e <48> b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 75
RSP: 0018:ffffc90000007d58 EFLAGS: 00000097
RAX: 0000000000000000 RBX: ffffffff94353c68 RCX: 0000000000000002
RDX: 0000000000000000 RSI: ffffffff8c3e9b00 RDI: ffffffff8e417920
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: ffff8880265ef2ab R11: 0000000000000000 R12: 0000000000000002
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff8881240e0000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2ef10ff8 CR3: 0000000026a54000 CR4: 00000000003526f0
Call Trace:
trace_lock_acquire include/trace/events/lock.h:23 [inline]
lock_acquire+0x301/0x370 kernel/locking/lockdep.c:5831
rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
rcu_read_lock include/linux/rcupdate.h:840 [inline]
advance_sched+0x718/0xd20 net/sched/sch_taprio.c:992
__run_hrtimer kernel/time/hrtimer.c:2032 [inline]
__hrtimer_run_queues+0x462/0x9c0 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:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:64
Code: b6 a4 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 63 b9 2e 00 fb f4 bc 48 03 00 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90
RSP: 0018:ffffffff8e607e10 EFLAGS: 00000246
RAX: 0000000006db54f5 RBX: ffffffff8e691480 RCX: ffffffff8b9ce2d5
RDX: 0000000000000000 RSI: ffffffff8e15d8c3 RDI: ffffffff8c3e9b80
RBP: fffffbfff1cd2290 R08: 0000000000000001 R09: ffffed101708678d
R10: ffff8880b8433c6b R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 1ffffffff1cc0fc6 R15: dffffc0000000000
arch_safe_halt arch/x86/include/asm/paravirt.h:62 [inline]
default_idle+0x9/0x10 arch/x86/kernel/process.c:768
default_idle_call+0x6c/0xb0 kernel/sched/idle.c:122
cpuidle_idle_call kernel/sched/idle.c:199 [inline]
do_idle+0x3a7/0x5b0 kernel/sched/idle.c:355
cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:454
rest_init+0x251/0x260 init/main.c:717
start_kernel+0x48e/0x490 init/main.c:1175
x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310
x86_64_start_kernel+0x12b/0x130 arch/x86/kernel/head64.c:291
common_startup_64+0x13e/0x158
task:syz.2.4921 state:R running task stack:27000 pid:24672 tgid:24668 ppid:17699 task_flags:0x400140 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5510 [inline]
__schedule+0x125c/0x6730 kernel/sched/core.c:7234
preempt_schedule_irq+0x50/0x90 kernel/sched/core.c:7556
irqentry_exit_to_kernel_mode_preempt include/linux/irq-entry-common.h:468 [inline]
irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:539 [inline]
irqentry_exit+0x205/0xa00 kernel/entry/common.c:167
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0010:unwind_next_frame+0x4d6/0x2090 arch/x86/kernel/unwind_orc.c:520
Code: e8 6f f3 ff ff 48 89 c1 48 85 c0 0f 84 dc 06 00 00 48 b8 00 00 00 00 00 fc ff df 4c 8d 79 05 4c 89 fa 48 c1 ea 03 0f b6 04 02 <4c> 89 fa 83 e2 07 38 d0 7f 08 84 c0 0f 85 51 15 00 00 0f b6 41 05
RSP: 0018:ffffc90010267050 EFLAGS: 00000a02
RAX: 0000000000000000 RBX: 0000000000000001 RCX: ffffffff91a0c6ac
RDX: 1ffffffff23418d6 RSI: 0000000000000000 RDI: ffffffff9117cc74
RBP: ffffc90010267108 R08: ffffffff91a0c6d0 R09: 0000000000000007
R10: 0000000000000200 R11: 000000000000f38f R12: ffffc90010267110
R13: ffffc900102670c0 R14: ffffc900102670f5 R15: ffffffff91a0c6b1
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_node_track_caller_noprof+0x331/0x830 mm/slub.c:5497
__kmemdup_nul mm/util.c:64 [inline]
kstrdup+0x51/0xe0 mm/util.c:84
kstrdup_const+0x63/0x80 mm/util.c:104
__kernfs_new_node+0x9b/0xa10 fs/kernfs/dir.c:661
kernfs_new_node+0x117/0x150 fs/kernfs/dir.c:751
__kernfs_create_file+0x53/0x350 fs/kernfs/file.c:1050
sysfs_add_file_mode_ns+0x207/0x3c0 fs/sysfs/file.c:316
create_files fs/sysfs/group.c:82 [inline]
internal_create_group+0x593/0xfb0 fs/sysfs/group.c:189
internal_create_groups+0x9d/0x150 fs/sysfs/group.c:229
setup_port+0x409/0x16e0 drivers/infiniband/core/sysfs.c:1202
ib_setup_port_attrs+0x201/0x600 drivers/infiniband/core/sysfs.c:1388
add_one_compat_dev+0x5b3/0x820 drivers/infiniband/core/device.c:979
rdma_dev_init_net+0x30a/0x590 drivers/infiniband/core/device.c:1195
ops_init+0x1e2/0x5f0 net/core/net_namespace.c:137
setup_net+0x118/0x3a0 net/core/net_namespace.c:446
copy_net_ns+0x46f/0x7c0 net/core/net_namespace.c:579
create_new_namespaces+0x3ea/0xac0 kernel/nsproxy.c:132
unshare_nsproxy_namespaces+0xf2/0x220 kernel/nsproxy.c:234
ksys_unshare+0x438/0xab0 kernel/fork.c:3268
__do_sys_unshare kernel/fork.c:3342 [inline]
__se_sys_unshare kernel/fork.c:3340 [inline]
__x64_sys_unshare+0x31/0x40 kernel/fork.c:3340
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: 0033:0x7f1e0339ce59
RSP: 002b:00007f1e042b8028 EFLAGS: 00000246 ORIG_RAX: 0000000000000110
RAX: ffffffffffffffda RBX: 00007f1e03616090 RCX: 00007f1e0339ce59
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000000006a040000
RBP: 00007f1e03432e6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f1e03616128 R14: 00007f1e03616090 R15: 00007ffe767477a8
rcu: rcu_preempt kthread starved for 10496 jiffies! g188857 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:26200 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: 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 06/10/2026
RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:64
Code: b6 a4 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 63 b9 2e 00 fb f4 bc 48 03 00 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90
RSP: 0018:ffffc90000197e00 EFLAGS: 00000246
RAX: 000000000607d7d7 RBX: ffff88801ea92540 RCX: ffffffff8b9ce2d5
RDX: 0000000000000000 RSI: ffffffff8e15d8c3 RDI: ffffffff8c3e9b80
RBP: ffffed1003d524a8 R08: 0000000000000001 R09: ffffed10170a678d
R10: ffff8880b8533c6b R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 1ffff92000032fc4 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff8881241e0000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fca067ea540 CR3: 000000002a36e000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 000000000000000c DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
arch_safe_halt arch/x86/include/asm/paravirt.h:62 [inline]
default_idle+0x9/0x10 arch/x86/kernel/process.c:768
default_idle_call+0x6c/0xb0 kernel/sched/idle.c:122
cpuidle_idle_call kernel/sched/idle.c:199 [inline]
do_idle+0x3a7/0x5b0 kernel/sched/idle.c:355
cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:454
start_secondary+0x21d/0x2d0 arch/x86/kernel/smpboot.c:312
common_startup_64+0x13e/0x158