rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 1-...!: (0 ticks this GP) idle=bf04/1/0x4000000000000000 softirq=151763/151763 fqs=0
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P23390/1:b..l P13723/1:b..l
rcu: (detected by 0, t=10502 jiffies, g=90853, q=545 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 13692 Comm: kworker/u8:9 Not tainted 6.15.0-rc5-syzkaller-00032-g0d8d44db295c #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/29/2025
Workqueue: krdsd rds_connect_worker
RIP: 0010:lock_acquire kernel/locking/lockdep.c:5866 [inline]
RIP: 0010:lock_acquire+0x15f/0x350 kernel/locking/lockdep.c:5823
Code: c7 c7 e4 20 cd 8d e8 00 ca d4 09 45 89 e0 89 e9 44 89 ea 65 ff 05 b9 3a 0c 12 48 81 24 24 00 02 00 00 44 89 f6 48 89 df 6a 00 <6a> 00 6a 00 ff b4 24 88 00 00 00 41 0f 94 c1 41 57 45 0f b6 c9 e8
RSP: 0018:ffffc90000a08cb8 EFLAGS: 00000046
RAX: 0000000000000001 RBX: ffffffff9adcc780 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff9adcc780
RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: ffffffff9adcc768 R12: 0000000000000001
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff888124adf000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000000200 CR3: 0000000029f87000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162
debug_object_deactivate+0x135/0x3a0 lib/debugobjects.c:873
debug_hrtimer_deactivate kernel/time/hrtimer.c:450 [inline]
debug_deactivate kernel/time/hrtimer.c:490 [inline]
__run_hrtimer kernel/time/hrtimer.c:1729 [inline]
__hrtimer_run_queues+0x46f/0xad0 kernel/time/hrtimer.c:1825
hrtimer_interrupt+0x397/0x8e0 kernel/time/hrtimer.c:1887
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline]
__sysvec_apic_timer_interrupt+0x108/0x3f0 arch/x86/kernel/apic/apic.c:1055
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline]
sysvec_apic_timer_interrupt+0x9f/0xc0 arch/x86/kernel/apic/apic.c:1049
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:stack_access_ok+0xc/0x200 arch/x86/kernel/unwind_orc.c:389
Code: ba fe ff ff 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 48 b8 00 00 00 00 00 fc ff df 41 57 <41> 56 4c 8d 77 08 41 55 41 54 49 89 d4 4c 89 f2 55 48 c1 ea 03 48
RSP: 0018:ffffc9001279f5a8 EFLAGS: 00000246
RAX: dffffc0000000000 RBX: 0000000000000001 RCX: ffffffff91179264
RDX: 0000000000000008 RSI: ffffc9001279ff50 RDI: ffffc9001279f628
RBP: ffffc9001279f670 R08: ffffffff91179268 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000005f54 R12: ffffc9001279f678
R13: ffffc9001279f628 R14: ffffc9001279ff58 R15: ffffc9001279f65c
deref_stack_reg arch/x86/kernel/unwind_orc.c:403 [inline]
unwind_next_frame+0xb7d/0x20a0 arch/x86/kernel/unwind_orc.c:585
arch_stack_walk+0x94/0x100 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_record_aux_stack+0xb8/0xd0 mm/kasan/generic.c:548
slab_free_hook mm/slub.c:2341 [inline]
slab_free mm/slub.c:4642 [inline]
kmem_cache_free+0x160/0x4d0 mm/slub.c:4744
sk_prot_free net/core/sock.c:2235 [inline]
__sk_destruct+0x5b3/0x980 net/core/sock.c:2332
sk_destruct+0xc2/0xf0 net/core/sock.c:2360
__sk_free+0xf4/0x3e0 net/core/sock.c:2371
sk_free+0x6a/0x90 net/core/sock.c:2382
sock_put include/net/sock.h:1944 [inline]
tcp_close+0xd3/0x120 net/ipv4/tcp.c:3251
inet_release+0x13c/0x280 net/ipv4/af_inet.c:435
__sock_release net/socket.c:647 [inline]
sock_release+0x8e/0x1d0 net/socket.c:675
rds_tcp_conn_path_connect+0x4aa/0x7f0 net/rds/tcp_connect.c:191
rds_connect_worker+0x1ac/0x2c0 net/rds/threads.c:176
process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3238
process_scheduled_works kernel/workqueue.c:3319 [inline]
worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400
kthread+0x3c2/0x780 kernel/kthread.c:464
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
task:syz-executor state:R running task stack:24152 pid:13723 tgid:13723 ppid:13712 task_flags:0x400140 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5382 [inline]
__schedule+0x116f/0x5de0 kernel/sched/core.c:6767
preempt_schedule_common+0x44/0xc0 kernel/sched/core.c:6947
preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
__raw_spin_unlock include/linux/spinlock_api_smp.h:143 [inline]
_raw_spin_unlock+0x3e/0x50 kernel/locking/spinlock.c:186
spin_unlock include/linux/spinlock.h:391 [inline]
copy_pte_range mm/memory.c:1194 [inline]
copy_pmd_range mm/memory.c:1255 [inline]
copy_pud_range mm/memory.c:1292 [inline]
copy_p4d_range mm/memory.c:1316 [inline]
copy_page_range+0x1952/0x5fe0 mm/memory.c:1410
dup_mmap kernel/fork.c:726 [inline]
dup_mm kernel/fork.c:1734 [inline]
copy_mm kernel/fork.c:1786 [inline]
copy_process+0x862b/0x91a0 kernel/fork.c:2429
kernel_clone+0xfc/0x960 kernel/fork.c:2844
__do_sys_clone+0xce/0x120 kernel/fork.c:2987
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0x260 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7536d851d3
RSP: 002b:00007ffc75bec508 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f7536d851d3
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000001
R10: 0000555574a7f7d0 R11: 0000000000000246 R12: 0000000000000000
R13: 00000000000927c0 R14: 00000000000c924f R15: 00007ffc75bec6a0
task:syz-executor state:R running task stack:27080 pid:23390 tgid:23390 ppid:23377 task_flags:0x400140 flags:0x00004002
Call Trace:
context_switch kernel/sched/core.c:5382 [inline]
__schedule+0x116f/0x5de0 kernel/sched/core.c:6767
preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7090
irqentry_exit+0x36/0x90 kernel/entry/common.c:354
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:lock_acquire+0x62/0x350 kernel/locking/lockdep.c:5870
Code: fe 0b 12 83 f8 07 0f 87 bc 02 00 00 89 c0 48 0f a3 05 42 f2 ec 0e 0f 82 74 02 00 00 8b 35 da 21 ed 0e 85 f6 0f 85 8d 00 00 00 <48> 8b 44 24 30 65 48 2b 05 19 fe 0b 12 0f 85 c7 02 00 00 48 83 c4
RSP: 0018:ffffc900046cf6d0 EFLAGS: 00000206
RAX: 0000000000000046 RBX: ffffffff8e3bf5c0 RCX: 000000009e84bfc7
RDX: 0000000000000000 RSI: ffffffff8dbbbc4f RDI: ffffffff8bf482a0
RBP: 0000000000000002 R08: 2a3e41e1447df377 R09: 0000000000000000
R10: 0000000000000005 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
rcu_read_lock include/linux/rcupdate.h:841 [inline]
class_rcu_constructor include/linux/rcupdate.h:1155 [inline]
kernfs_root+0x34/0x2a0 fs/kernfs/kernfs-internal.h:73
kernfs_root_is_locked fs/kernfs/kernfs-internal.h:107 [inline]
kernfs_rcu_name fs/kernfs/kernfs-internal.h:112 [inline]
kernfs_sd_compare fs/kernfs/dir.c:349 [inline]
kernfs_link_sibling+0x269/0x760 fs/kernfs/dir.c:380
kernfs_add_one+0x20a/0x840 fs/kernfs/dir.c:810
__kernfs_create_file+0x295/0x350 fs/kernfs/file.c:1067
sysfs_add_file_mode_ns+0x207/0x3c0 fs/sysfs/file.c:319
create_files fs/sysfs/group.c:76 [inline]
internal_create_group+0x578/0xf30 fs/sysfs/group.c:183
internal_create_groups+0x9d/0x150 fs/sysfs/group.c:223
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+0x558/0x7d0 drivers/infiniband/core/device.c:968
rdma_dev_init_net+0x2b1/0x530 drivers/infiniband/core/device.c:1184
ops_init+0x1df/0x5f0 net/core/net_namespace.c:138
setup_net+0x21e/0x850 net/core/net_namespace.c:364
copy_net_ns+0x2a6/0x5f0 net/core/net_namespace.c:518
create_new_namespaces+0x3ea/0xad0 kernel/nsproxy.c:110
unshare_nsproxy_namespaces+0xc0/0x1f0 kernel/nsproxy.c:228
ksys_unshare+0x45b/0xa40 kernel/fork.c:3375
__do_sys_unshare kernel/fork.c:3446 [inline]
__se_sys_unshare kernel/fork.c:3444 [inline]
__x64_sys_unshare+0x31/0x40 kernel/fork.c:3444
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0x260 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff892b90167
RSP: 002b:00007ffcad7e6a68 EFLAGS: 00000202 ORIG_RAX: 0000000000000110
RAX: ffffffffffffffda RBX: 00007ff892db5f40 RCX: 00007ff892b90167
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040000000
RBP: 00007ff892db6738 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000008
R13: 0000000000000003 R14: 0000000000000009 R15: 0000000000000000
rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g90853 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: Possible timer handling issue on cpu=1 timer-softirq=62943
rcu: rcu_preempt kthread starved for 10502 jiffies! g90853 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:27304 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5382 [inline]
__schedule+0x116f/0x5de0 kernel/sched/core.c:6767
__schedule_loop kernel/sched/core.c:6845 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:6860
schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x1ea/0xb00 kernel/rcu/tree.c:2046
rcu_gp_kthread+0x270/0x380 kernel/rcu/tree.c:2248
kthread+0x3c2/0x780 kernel/kthread.c:464
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245