rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P7296
rcu: (detected by 1, t=10502 jiffies, g=19125, q=884 ncpus=2)
task:syz.3.328 state:R running task stack:26080 pid:7296 tgid:7295 ppid:5834 task_flags:0x400140 flags:0x00080000
Call Trace:
sched_show_task+0x49d/0x630 kernel/sched/core.c:7823
rcu_print_detail_task_stall_rnp kernel/rcu/tree_stall.h:292 [inline]
print_other_cpu_stall+0xf7a/0x1340 kernel/rcu/tree_stall.h:681
check_cpu_stall kernel/rcu/tree_stall.h:857 [inline]
rcu_pending kernel/rcu/tree.c:3671 [inline]
rcu_sched_clock_irq+0xa47/0x11b0 kernel/rcu/tree.c:2706
update_process_times+0x23c/0x2f0 kernel/time/timer.c:2473
tick_sched_handle kernel/time/tick-sched.c:298 [inline]
tick_nohz_handler+0x3e9/0x710 kernel/time/tick-sched.c:319
__run_hrtimer kernel/time/hrtimer.c:1777 [inline]
__hrtimer_run_queues+0x4d0/0xc70 kernel/time/hrtimer.c:1841
hrtimer_interrupt+0x45b/0xaa0 kernel/time/hrtimer.c:1903
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1045 [inline]
__sysvec_apic_timer_interrupt+0x102/0x410 arch/x86/kernel/apic/apic.c:1062
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1056
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lock_acquire+0x16c/0x350 kernel/locking/lockdep.c:5872
Code: 00 00 00 00 9c 8f 44 24 30 f7 44 24 30 00 02 00 00 0f 85 cd 00 00 00 f7 44 24 08 00 02 00 00 74 01 fb 65 48 8b 05 14 c9 d7 10 <48> 3b 44 24 58 0f 85 f2 00 00 00 48 83 c4 60 5b 41 5c 41 5d 41 5e
RSP: 0018:ffffc9001ca2f848 EFLAGS: 00000206
RAX: da5e6d8c086ca400 RBX: 0000000000000000 RCX: da5e6d8c086ca400
RDX: 0000000000000000 RSI: ffffffff8d9760ce RDI: ffffffff8bbf81e0
RBP: ffffffff81e13302 R08: 0000000000000000 R09: ffffffff81e13302
R10: dffffc0000000000 R11: fffffbfff1efbd6f R12: 0000000000000002
R13: ffffffff8df3d980 R14: 0000000000000000 R15: 0000000000000246
rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
rcu_read_lock include/linux/rcupdate.h:867 [inline]
____bpf_get_current_ancestor_cgroup_id kernel/bpf/helpers.c:431 [inline]
bpf_get_current_ancestor_cgroup_id+0x3e/0x3f0 kernel/bpf/helpers.c:425
bpf_prog_87faaa71b9a62b97+0x67/0x6f
bpf_dispatcher_nop_func include/linux/bpf.h:1364 [inline]
__bpf_prog_run include/linux/filter.h:721 [inline]
bpf_prog_run include/linux/filter.h:728 [inline]
bpf_test_run+0x313/0x7a0 net/bpf/test_run.c:423
bpf_prog_test_run_skb+0xda9/0x1d70 net/bpf/test_run.c:1158
bpf_prog_test_run+0x2c7/0x340 kernel/bpf/syscall.c:4711
__sys_bpf+0x562/0x860 kernel/bpf/syscall.c:6190
__do_sys_bpf kernel/bpf/syscall.c:6282 [inline]
__se_sys_bpf kernel/bpf/syscall.c:6280 [inline]
__x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:6280
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ffa90d8f749
Code: 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 01 48
RSP: 002b:00007ffa91c9c038 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 00007ffa90fe5fa0 RCX: 00007ffa90d8f749
RDX: 0000000000000050 RSI: 00002000000002c0 RDI: 000000000000000a
RBP: 00007ffa90e13f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffa90fe6038 R14: 00007ffa90fe5fa0 R15: 00007ffd179a2c78
rcu: rcu_preempt kthread starved for 10153 jiffies! g19125 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:27296 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5257 [inline]
__schedule+0x14bc/0x5030 kernel/sched/core.c:6864
__schedule_loop kernel/sched/core.c:6946 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6961
schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2083
rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2285
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x599/0xb30 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:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:82
Code: cc cc cc cc cc cc cc 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 33 70 0c 00 f3 0f 1e fa fb f4 c8 f2 02 00 cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffffff8dc07d80 EFLAGS: 000002c6
RAX: 03d247c21c51bb00 RBX: ffffffff8197acb7 RCX: 03d247c21c51bb00
RDX: 0000000000000001 RSI: ffffffff8d78f71d RDI: ffffffff8bbf81e0
RBP: ffffffff8dc07ea8 R08: ffff8880b86336db R09: 1ffff110170c66db
R10: dffffc0000000000 R11: ffffed10170c66dc R12: ffffffff8f7deb70
R13: 0000000000000000 R14: 0000000000000000 R15: 1ffffffff1b92a60
FS: 0000000000000000(0000) GS:ffff888125eba000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f40e76a3a57 CR3: 0000000031bc0000 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+0x73/0xb0 kernel/sched/idle.c:122
cpuidle_idle_call kernel/sched/idle.c:190 [inline]
do_idle+0x1e7/0x510 kernel/sched/idle.c:330
cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:428
rest_init+0x2de/0x300 init/main.c:757
start_kernel+0x3a7/0x410 init/main.c:1206
x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310
x86_64_start_kernel+0x143/0x1c0 arch/x86/kernel/head64.c:291
common_startup_64+0x13e/0x147