rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1):
P4189/1:b..l
(detected by 1, t=10502 jiffies, g=55133, q=23363)
task:syz-executor state:R running task stack:21840 pid: 4189 ppid: 4183 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11ef/0x43c0 kernel/sched/core.c:6395
preempt_schedule_irq+0xbb/0x160 kernel/sched/core.c:6799
irqentry_exit+0x63/0x70 kernel/entry/common.c:432
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:lock_is_held_type+0x13a/0x190 kernel/locking/lockdep.c:5671
Code: 75 40 48 c7 04 24 00 00 00 00 9c 8f 04 24 f7 04 24 00 02 00 00 75 46 41 f7 c5 00 02 00 00 74 01 fb 65 48 8b 04 25 28 00 00 00 <48> 3b 44 24 08 75 3c 89 e8 48 83 c4 10 5b 41 5c 41 5d 41 5e 41 5f
RSP: 0018:ffffc90002f3f7f0 EFLAGS: 00000206
RAX: cf3ff72face34a00 RBX: ffff88807b22bb80 RCX: cf3ff72face34a00
RDX: 0000000000000000 RSI: ffffffff8a2b43a0 RDI: ffffffff8a7a0700
RBP: 0000000000000000 R08: dffffc0000000000 R09: 1ffffffff203ac18
R10: dffffc0000000000 R11: fffffbfff203ac19 R12: 0000000000000004
R13: 0000000000000246 R14: ffffffff8c344c08 R15: ffff88807b22c710
lock_is_held include/linux/lockdep.h:287 [inline]
task_css include/linux/cgroup.h:496 [inline]
mem_cgroup_from_task+0x5e/0x110 mm/memcontrol.c:935
get_obj_cgroup_from_current+0x146/0x2f0 mm/memcontrol.c:2926
memcg_slab_pre_alloc_hook mm/slab.h:283 [inline]
slab_pre_alloc_hook+0x7e/0xc0 mm/slab.h:497
slab_alloc_node mm/slub.c:3139 [inline]
slab_alloc mm/slub.c:3233 [inline]
kmem_cache_alloc+0x3d/0x290 mm/slub.c:3238
anon_vma_alloc mm/rmap.c:90 [inline]
anon_vma_fork+0xe3/0x500 mm/rmap.c:356
dup_mmap kernel/fork.c:574 [inline]
dup_mm kernel/fork.c:1466 [inline]
copy_mm+0xa06/0x13f0 kernel/fork.c:1518
copy_process+0x17eb/0x3e20 kernel/fork.c:2290
kernel_clone+0x23f/0x990 kernel/fork.c:2679
__do_sys_clone kernel/fork.c:2796 [inline]
__se_sys_clone kernel/fork.c:2780 [inline]
__x64_sys_clone+0x19a/0x210 kernel/fork.c:2780
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: 0033:0x7f6db7e688d2
RSP: 002b:00007ffccf4d2b80 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 00007ffccf4d2b80 RCX: 00007f6db7e688d2
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 00007ffccf4d2d0c R08: 0000000000000000 R09: 0000000000000001
R10: 00005555816c07d0 R11: 0000000000000246 R12: 0000000000000001
R13: 00000000000927c0 R14: 00000000000b6511 R15: 00007ffccf4d2d60
rcu: rcu_preempt kthread starved for 10502 jiffies! g55133 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:27536 pid: 15 ppid: 2 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11ef/0x43c0 kernel/sched/core.c:6395
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
schedule_timeout+0x184/0x2d0 kernel/time/timer.c:2117
rcu_gp_fqs_loop+0x2be/0x11d0 kernel/rcu/tree.c:1972
rcu_gp_kthread+0x9b/0x370 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: 11195 Comm: syz.7.1700 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:next_tid mm/slub.c:2261 [inline]
RIP: 0010:slab_alloc_node mm/slub.c:3209 [inline]
RIP: 0010:slab_alloc mm/slub.c:3233 [inline]
RIP: 0010:__kmalloc_track_caller+0xc2/0x330 mm/slub.c:4930
Code: 49 8b 7d 00 40 f6 c7 0f 0f 85 75 02 00 00 48 8d 47 08 48 89 f9 48 83 c9 08 48 39 c1 0f 85 63 02 00 00 41 8b 45 28 49 8b 1c 04 <48> 8d 4a 08 4c 89 e0 65 48 0f c7 0f 0f 94 c0 a8 01 74 9c 4c 89 64
RSP: 0018:ffffc90003a569f0 EFLAGS: 00000246
RAX: 0000000000000040 RBX: ffff88805287dc00 RCX: 000000000003de08
RDX: 0000000000039d60 RSI: 0000000000000080 RDI: 000000000003de00
RBP: 0000000000000a20 R08: ffffffff8d89f82f R09: 1ffffffff1b13f05
R10: dffffc0000000000 R11: fffffbfff1b13f06 R12: ffff88805287db00
R13: ffff888016c418c0 R14: 0000000000000080 R15: ffff888016c418c0
FS: 00007f1cf30196c0(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000001000 CR3: 0000000052def000 CR4: 00000000003506f0
Call Trace:
__do_krealloc mm/slab_common.c:1244 [inline]
krealloc+0x5a/0xf0 mm/slab_common.c:1277
nf_ct_ext_add+0x42e/0x660 net/netfilter/nf_conntrack_extend.c:73
nf_ct_labels_ext_add include/net/netfilter/nf_conntrack_labels.h:37 [inline]
init_conntrack+0x768/0x14d0 net/netfilter/nf_conntrack_core.c:1712
resolve_normal_ct net/netfilter/nf_conntrack_core.c:1805 [inline]
nf_conntrack_in+0xd38/0x1730 net/netfilter/nf_conntrack_core.c:1960
nf_hook_entry_hookfn include/linux/netfilter.h:142 [inline]
nf_hook_slow+0xb9/0x200 net/netfilter/core.c:584
nf_hook+0x205/0x360 include/linux/netfilter.h:257
__ip_local_out+0x4b7/0x5e0 net/ipv4/ip_output.c:115
ip_local_out net/ipv4/ip_output.c:124 [inline]
__ip_queue_xmit+0x10f8/0x1c00 net/ipv4/ip_output.c:538
__tcp_transmit_skb+0x1d11/0x3200 net/ipv4/tcp_output.c:1404
tcp_transmit_skb net/ipv4/tcp_output.c:1422 [inline]
tcp_connect+0x21ac/0x4970 net/ipv4/tcp_output.c:3904
tcp_v4_connect+0x103e/0x1a80 net/ipv4/tcp_ipv4.c:323
__inet_stream_connect+0x244/0xd70 net/ipv4/af_inet.c:672
inet_stream_connect+0x62/0xa0 net/ipv4/af_inet.c:736
p9_fd_create_tcp+0x464/0x600 net/9p/trans_fd.c:1031
p9_client_create+0x84a/0x1010 net/9p/client.c:1044
v9fs_session_init+0x1f0/0x1830 fs/9p/v9fs.c:409
v9fs_mount+0x72/0x850 fs/9p/vfs_super.c:126
legacy_get_tree+0xe6/0x180 fs/fs_context.c:611
vfs_get_tree+0x88/0x270 fs/super.c:1530
do_new_mount+0x24a/0xa40 fs/namespace.c:3034
do_mount fs/namespace.c:3377 [inline]
__do_sys_mount fs/namespace.c:3585 [inline]
__se_sys_mount+0x2e3/0x3d0 fs/namespace.c:3562
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: 0033:0x7f1cf4de0e59
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:00007f1cf3019028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f1cf505a090 RCX: 00007f1cf4de0e59
RDX: 00002000000006c0 RSI: 0000200000000680 RDI: 0000200000000000
RBP: 00007f1cf4e76d6f R08: 0000200000000080 R09: 0000000000000000
R10: 0000000000008010 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f1cf505a128 R14: 00007f1cf505a090 R15: 00007ffd27dfe118