rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5263/1:b..l
(detected by 1, t=10502 jiffies, g=17521, q=166 ncpus=2)
task:syz.3.188 state:R running task stack:26224 pid:5263 ppid:4273 flags:0x00004000
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5245 [inline]
__schedule+0x11d1/0x40e0 kernel/sched/core.c:6562
preempt_schedule_irq+0xbb/0x160 kernel/sched/core.c:6874
irqentry_exit+0x63/0x70 kernel/entry/common.c:439
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:cpu_max_bits_warn include/linux/cpumask.h:110 [inline]
RIP: 0010:cpumask_check include/linux/cpumask.h:117 [inline]
RIP: 0010:cpumask_test_cpu include/linux/cpumask.h:444 [inline]
RIP: 0010:cpu_online include/linux/cpumask.h:1030 [inline]
RIP: 0010:trace_lock_acquire include/trace/events/lock.h:24 [inline]
RIP: 0010:lock_acquire+0xae/0x4a0 kernel/locking/lockdep.c:5633
Code: 08 f8 f3 f3 f3 0f 1f 44 00 00 65 44 8b 35 7a d9 9d 7e 48 c7 c0 30 c5 1f 8e 48 c1 e8 03 42 0f b6 04 38 84 c0 0f 85 9d 02 00 00 <44> 3b 35 eb 84 bb 0c 0f 83 a2 01 00 00 45 89 f4 41 c1 ee 06 4a 8d
RSP: 0018:ffffc90004ccfda0 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000002
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8cb2d620
RBP: ffffc90004ccfec0 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: fffffbfff1c3f866 R12: 0000000000000000
R13: 1ffff92000999fc0 R14: 0000000000000001 R15: dffffc0000000000
rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
rcu_read_lock include/linux/rcupdate.h:791 [inline]
__task_pid_nr_ns+0x44/0x460 kernel/pid.c:497
task_tgid_vnr include/linux/sched.h:1628 [inline]
__ia32_sys_getpid+0x19/0x20 kernel/sys.c:953
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f045f794cd7
RSP: 002b:00007fff82d3e6c8 EFLAGS: 00000202 ORIG_RAX: 0000000000000027
RAX: ffffffffffffffda RBX: 00007fff82d3e830 RCX: 00007f045f794cd7
RDX: 00007fff82d3e700 RSI: 00007fff82d3e830 RDI: 0000000000000021
RBP: 0000000000000000 R08: 00007f045fa00000 R09: 00007f045fa02000
R10: 00000000812fe778 R11: 0000000000000202 R12: 00007f045fa16038
R13: 0000000000010350 R14: ffffffff812fe2c8 R15: 00007f0460545720
</TASK>
rcu: rcu_preempt kthread starved for 9607 jiffies! g17521 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:27184 pid:16 ppid:2 flags:0x00004000
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5245 [inline]
__schedule+0x11d1/0x40e0 kernel/sched/core.c:6562
schedule+0xb9/0x180 kernel/sched/core.c:6638
schedule_timeout+0x184/0x2d0 kernel/time/timer.c:2168
rcu_gp_fqs_loop+0x303/0x1340 kernel/rcu/tree.c:1706
rcu_gp_kthread+0x99/0x3b0 kernel/rcu/tree.c:1905
kthread+0x29d/0x330 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
</TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 1 PID: 0 Comm: swapper/1 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:default_idle+0xb/0x10 arch/x86/kernel/process.c:742
Code: 48 89 df e8 a7 10 9d f7 e9 44 ff ff ff e8 7d 07 f6 ff 00 00 cc cc 00 00 cc cc 00 00 cc cc 00 66 90 0f 00 2d 87 5d 50 00 fb f4 <c3> 0f 1f 40 00 41 57 41 56 53 49 be 00 00 00 00 00 fc ff df 65 48
RSP: 0018:ffffc90000177de8 EFLAGS: 000002c6
RAX: 2091e558915ef000 RBX: ffffffff8a3651a7 RCX: 2091e558915ef000
RDX: 0000000000000001 RSI: ffffffff8a8c1220 RDI: ffffffff8adf0c20
RBP: ffffc90000177f20 R08: ffff8880b8f3580b R09: 1ffff110171e6b01
R10: dffffc0000000000 R11: ffffed10171e6b02 R12: 1ffff9200002efc8
R13: dffffc0000000000 R14: ffff8880176c9dc0 R15: 0000000000000001
FS: 0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f86f1902eca CR3: 000000007f5c5000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
default_idle_call+0x84/0xc0 kernel/sched/idle.c:109
cpuidle_idle_call kernel/sched/idle.c:191 [inline]
do_idle+0x20d/0x5a0 kernel/sched/idle.c:303
cpu_startup_entry+0x3f/0x60 kernel/sched/idle.c:401
start_secondary+0xe4/0xf0 arch/x86/kernel/smpboot.c:281
secondary_startup_64_no_verify+0xcf/0xdb
</TASK>