rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P4305/1:b..l P4399/1:b..l
(detected by 0, t=10503 jiffies, g=6117, q=773)
task:kworker/1:8 state:R running task stack:24384 pid: 4399 ppid: 2 flags:0x00004000
Workqueue: events_power_efficient gc_worker
Call Trace:
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11bb/0x4390 kernel/sched/core.c:6395
preempt_schedule_irq+0xb1/0x150 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:seqcount_lockdep_reader_access+0x17b/0x1c0 include/linux/seqlock.h:106
Code: f9 4d 85 e4 75 16 e8 64 af 68 f9 eb 15 e8 5d af 68 f9 e8 98 ca 92 01 4d 85 e4 74 ea e8 4e af 68 f9 fb 48 c7 04 24 0e 36 e0 45 <4b> c7 04 3e 00 00 00 00 66 43 c7 44 3e 09 00 00 43 c6 44 3e 0b 00
RSP: 0018:ffffc9000384fa20 EFLAGS: 00000293
RAX: ffffffff880f1cc2 RBX: 0000000000000000 RCX: ffff88807b5e5940
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc9000384fad0 R08: dffffc0000000000 R09: fffffbfff1ff542c
R10: fffffbfff1ff542c R11: 1ffffffff1ff542b R12: 0000000000000200
R13: ffff88801e5c8000 R14: 1ffff92000709f44 R15: dffffc0000000000
nf_conntrack_get_ht include/net/netfilter/nf_conntrack.h:338 [inline]
gc_worker+0x2e2/0x13a0 net/netfilter/nf_conntrack_core.c:1472
process_one_work+0x863/0x1000 kernel/workqueue.c:2310
worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457
kthread+0x436/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
task:syz-executor state:R running task stack:21856 pid: 4305 ppid: 4301 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11bb/0x4390 kernel/sched/core.c:6395
preempt_schedule_irq+0xb1/0x150 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_acquire+0x1f2/0x3f0 kernel/locking/lockdep.c:5627
Code: 00 9c 8f 84 24 80 00 00 00 f6 84 24 81 00 00 00 02 0f 85 f6 00 00 00 41 f7 c6 00 02 00 00 74 01 fb 48 c7 44 24 60 0e 36 e0 45 <4b> c7 44 3d 00 00 00 00 00 66 43 c7 44 3d 09 00 00 43 c6 44 3d 0b
RSP: 0018:ffffc9000303f2e0 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 0000000000000000 RCX: 02d7dab88dd0eb00
RDX: 0000000000000000 RSI: ffffffff8a0b2e80 RDI: ffffffff8a59e800
RBP: ffffc9000303f3e8 R08: dffffc0000000000 R09: fffffbfff1ff5419
R10: fffffbfff1ff5419 R11: 1ffffffff1ff5418 R12: ffffffff8c11c720
R13: 1ffff92000607e68 R14: 0000000000000246 R15: dffffc0000000000
rcu_lock_acquire+0x2a/0x30 include/linux/rcupdate.h:313
rcu_read_lock include/linux/rcupdate.h:740 [inline]
pfn_valid include/linux/mmzone.h:1522 [inline]
__virt_addr_valid+0x17f/0x470 arch/x86/mm/physaddr.c:65
check_heap_object mm/usercopy.c:228 [inline]
__check_object_size+0xa8/0x410 mm/usercopy.c:286
check_object_size include/linux/thread_info.h:199 [inline]
check_copy_size include/linux/thread_info.h:232 [inline]
copy_to_user include/linux/uaccess.h:199 [inline]
xt_obj_to_user+0x9d/0x120 net/netfilter/x_tables.c:299
xt_target_to_user+0x97/0x270 net/netfilter/x_tables.c:343
copy_entries_to_user net/ipv4/netfilter/ip_tables.c:860 [inline]
get_entries net/ipv4/netfilter/ip_tables.c:1023 [inline]
do_ipt_get_ctl+0xcb6/0x1070 net/ipv4/netfilter/ip_tables.c:1669
nf_getsockopt+0x25e/0x280 net/netfilter/nf_sockopt.c:116
ip_getsockopt+0x115a/0x1590 net/ipv4/ip_sockglue.c:1797
tcp_getsockopt+0x1e3/0x2390 net/ipv4/tcp.c:4319
__sys_getsockopt+0x1b0/0x230 net/socket.c:2257
__do_sys_getsockopt net/socket.c:2272 [inline]
__se_sys_getsockopt net/socket.c:2269 [inline]
__x64_sys_getsockopt+0xb1/0xc0 net/socket.c:2269
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: 0033:0x7ff2faa7b48a
RSP: 002b:00007ffedf4901a8 EFLAGS: 00000216 ORIG_RAX: 0000000000000037
RAX: ffffffffffffffda RBX: 00007ffedf490230 RCX: 00007ff2faa7b48a
RDX: 0000000000000041 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 0000000000000003 R08: 00007ffedf4901cc R09: 0079746972756365
R10: 00007ffedf490230 R11: 0000000000000216 R12: 00007ff2faca3960
R13: 00007ffedf4901cc R14: 0000000000000000 R15: 00007ff2faca4020
rcu: rcu_preempt kthread starved for 10582 jiffies! g6117 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:27584 pid: 15 ppid: 2 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11bb/0x4390 kernel/sched/core.c:6395
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
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 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 4429 Comm: syz.2.34 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:27 [inline]
RIP: 0010:check_kcov_mode kernel/kcov.c:172 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0xc/0x60 kernel/kcov.c:206
Code: 89 fb e8 17 00 00 00 48 8b 3d d0 6b f1 0b 48 89 de 5b e9 d7 9e 43 00 00 00 cc cc 00 00 cc 48 8b 04 24 65 48 8b 0d a4 a3 8a 7e <65> 8b 15 a5 a3 8a 7e 81 e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75
RSP: 0018:ffffc9000391fee0 EFLAGS: 00000046
RAX: ffffffff817dee45 RBX: ffffffff8166305d RCX: ffff88807b879dc0
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: ffff88807b879dc0 R09: 0000000000000003
R10: 0000000000000002 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: ffffc9000391ff58 R15: 000000000000000f
FS: 00007fc53d3f36c0(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000000058 CR3: 0000000020197000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
trace_hardirqs_off+0x65/0x70 kernel/trace/trace_preemptirq.c:82
local_irq_disable_exit_to_user+0x1d/0x20 include/linux/entry-common.h:211
__syscall_exit_to_user_mode_work kernel/entry/common.c:295 [inline]
syscall_exit_to_user_mode+0xe/0x40 kernel/entry/common.c:307
do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fc53dd84747
Code: ff ff 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
RSP: 002b:00007fc53d3f30e8 EFLAGS: 00000246
RAX: 00000000000000ca RBX: 00007fc53dfdafa8 RCX: 00007fc53dd84749
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007fc53dfdafa8
RBP: 00007fc53dfdafa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fc53dfdb038 R14: 00007ffd9c6e9610 R15: 00007ffd9c6e96f8
sched: RT throttling activated