[v6.1] INFO: rcu detected stall in sys_clone3 (4)

Hello,

syzbot found the following issue on:

HEAD commit: 3dfebb87d7eb Linux 6.1.133
git tree: linux-6.1.y
console output: https://syzkaller.appspot.com/x/log.txt?x=11f3b23f980000
kernel config: https://syzkaller.appspot.com/x/.config?x=98f87318ae7e5ebb
dashboard link: https://syzkaller.appspot.com/bug?extid=506480e3d185b681e48d
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/d6040a992ff7/disk-3dfebb87.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/7d99423d8a71/vmlinux-3dfebb87.xz
kernel image: https://storage.googleapis.com/syzbot-assets/2098792ab6b2/bzImage-3dfebb87.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: [email protected]

IPVS: dh: UDP 224.0.0.2:0 - no destination available
IPVS: dh: UDP 224.0.0.2:0 - no destination available
IPVS: dh: UDP 224.0.0.2:0 - no destination available
IPVS: dh: UDP 224.0.0.2:0 - no destination available
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P11882/2:b..l
(detected by 1, t=10502 jiffies, g=66965, q=351 ncpus=2)
task:syz.0.1935 state:R running task stack:25864 pid:11882 ppid:4258 flags:0x00004000
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5244 [inline]
__schedule+0x143f/0x4570 kernel/sched/core.c:6561
preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6873
irqentry_exit+0x53/0x80 kernel/entry/common.c:439
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:lock_acquire+0x1/0x5a0 kernel/locking/lockdep.c:5630
Code: fd ff ff 48 c7 c7 78 f0 a0 8e e8 0a 57 77 00 e9 a2 fd ff ff 0f 1f 44 00 00 65 8b 05 c1 ba 97 7e a9 00 ff ff 00 0f 95 c0 c3 55 <48> 89 e5 41 57 41 56 41 55 41 54 53 48 83 e4 e0 48 81 ec 20 01 00
RSP: 0018:ffffc90004a8f880 EFLAGS: 00000246
RAX: 0000000000000002 RBX: ffff888076ff2010 RCX: 0000000000000002
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8d32e740
RBP: 1ffff11004a3a332 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: dffffc0000000001 R12: ffff8880251d1990
R13: dffffc0000000000 R14: ffffffff81e9d224 R15: ffff888076ff2000
rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
rcu_read_lock include/linux/rcupdate.h:791 [inline]
percpu_ref_tryget_many include/linux/percpu-refcount.h:241 [inline]
percpu_ref_tryget+0x31/0x170 include/linux/percpu-refcount.h:266
css_tryget include/linux/cgroup.h:357 [inline]
get_mem_cgroup_from_objcg+0xc8/0x150 include/linux/memcontrol.h:523
obj_cgroup_charge_pages mm/memcontrol.c:3099 [inline]
__memcg_kmem_charge_page+0x233/0x3b0 mm/memcontrol.c:3127
memcg_kmem_charge_page include/linux/memcontrol.h:1762 [inline]
memcg_charge_kernel_stack+0x2e1/0x710 kernel/fork.c:259
alloc_thread_stack_node kernel/fork.c:297 [inline]
dup_task_struct+0x15b/0x6d0 kernel/fork.c:989
copy_process+0x637/0x40a0 kernel/fork.c:2096
kernel_clone+0x222/0x920 kernel/fork.c:2681
__do_sys_clone3 kernel/fork.c:2980 [inline]
__se_sys_clone3+0x3eb/0x440 kernel/fork.c:2964
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fb34b1c19c9
RSP: 002b:00007ffde60a78b8 EFLAGS: 00000202 ORIG_RAX: 00000000000001b3
RAX: ffffffffffffffda RBX: 00007fb34b143dd0 RCX: 00007fb34b1c19c9
RDX: 00007fb34b143dd0 RSI: 0000000000000058 RDI: 00007ffde60a7900
RBP: 00007fb34c04c6c0 R08: 00007fb34c04c6c0 R09: 00007ffde60a79e7
R10: 0000000000000008 R11: 0000000000000202 R12: ffffffffffffffa8
R13: 000000000000006e R14: 00007ffde60a7900 R15: 00007ffde60a79e8
</TASK>
rcu: rcu_preempt kthread starved for 9060 jiffies! g66965 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:26712 pid:16 ppid:2 flags:0x00004000
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5244 [inline]
__schedule+0x143f/0x4570 kernel/sched/core.c:6561
schedule+0xbf/0x180 kernel/sched/core.c:6637
schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1965
rcu_gp_fqs_loop+0x2d2/0x1150 kernel/rcu/tree.c:1706
rcu_gp_kthread+0xa3/0x3b0 kernel/rcu/tree.c:1905
kthread+0x28d/0x320 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 6.1.133-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
RIP: 0010:native_save_fl arch/x86/include/asm/irqflags.h:22 [inline]
RIP: 0010:arch_local_save_flags arch/x86/include/asm/irqflags.h:70 [inline]
RIP: 0010:arch_irqs_disabled arch/x86/include/asm/irqflags.h:130 [inline]
RIP: 0010:acpi_safe_halt drivers/acpi/processor_idle.c:112 [inline]
RIP: 0010:acpi_idle_do_entry+0x10f/0x340 drivers/acpi/processor_idle.c:567
Code: a8 ce f6 48 83 e3 08 0f 85 0b 01 00 00 4c 8d 74 24 20 e8 44 65 d5 f6 0f 1f 44 00 00 e8 6a a4 ce f6 0f 00 2d f3 b5 ad 00 fb f4 <4c> 89 f3 48 c1 eb 03 42 80 3c 3b 00 74 08 4c 89 f7 e8 0b 06 26 f7
RSP: 0018:ffffc90000177b80 EFLAGS: 000002d3
RAX: ffffffff8abc05e6 RBX: 0000000000000000 RCX: ffff888018c09dc0
RDX: 0000000000000000 RSI: ffffffff8b0c1dc0 RDI: ffffffff8b5f70e0
RBP: ffffc90000177c10 R08: ffffffff8abc05c8 R09: ffffed10031813b9
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff9200002ef70
R13: ffff88801b36b804 R14: ffffc90000177ba0 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f49fad12866 CR3: 000000001df9e000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 000000000346000e DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
<IRQ>
</IRQ>
<TASK>
acpi_idle_enter+0x352/0x4f0 drivers/acpi/processor_idle.c:704
cpuidle_enter_state+0x516/0xf80 drivers/cpuidle/cpuidle.c:239
cpuidle_enter+0x59/0x90 drivers/cpuidle/cpuidle.c:356
call_cpuidle kernel/sched/idle.c:155 [inline]
cpuidle_idle_call kernel/sched/idle.c:236 [inline]
do_idle+0x3ce/0x680 kernel/sched/idle.c:303
cpu_startup_entry+0x3d/0x60 kernel/sched/idle.c:401
start_secondary+0xe4/0xf0 arch/x86/kernel/smpboot.c:281
secondary_startup_64_no_verify+0xcf/0xdb
</TASK>
IPVS: dh: UDP 224.0.0.2:0 - no destination available
IPVS: dh: UDP 224.0.0.2:0 - no destination available
IPVS: dh: UDP 224.0.0.2:0 - no destination available
IPVS: dh: UDP 224.0.0.2:0 - no destination available
IPVS: dh: UDP 224.0.0.2:0 - no destination available
IPVS: dh: UDP 224.0.0.2:0 - no destination available
IPVS: dh: UDP 224.0.0.2:0 - no destination available
IPVS: dh: UDP 224.0.0.2:0 - no destination available
IPVS: dh: UDP 224.0.0.2:0 - no destination available


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