rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P6230/2:b..l
rcu: 	(detected by 0, t=10502 jiffies, g=10425, q=704 ncpus=2)
task:syz.1.62        state:R  running task     stack:26672 pid:6230  tgid:6229  ppid:5831   task_flags:0x400040 flags:0x00004006
Call Trace:
 <TASK>
 __schedule+0x1798/0x4cc0
 preempt_schedule_irq+0xb5/0x150
 irqentry_exit+0x6f/0x90
 asm_sysvec_apic_timer_interrupt+0x1a/0x20
RIP: 0010:lock_acquire+0x175/0x360
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 ab 57 ae 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:ffffc900046bf250 EFLAGS: 00000206
RAX: 2d288418509ee000 RBX: 0000000000000000 RCX: 2d288418509ee000
RDX: 0000000000000000 RSI: ffffffff8d71699d RDI: ffffffff8b9e6fe0
RBP: ffffffff822a4b35 R08: 0000000000000000 R09: ffffffff822a4b35
R10: dffffc0000000000 R11: fffff940008a08d9 R12: 0000000000000002
R13: ffffffff8dd3aca0 R14: 0000000000000000 R15: 0000000000000246
 percpu_ref_tryget+0x31/0x180
 get_mem_cgroup_from_mm+0x102/0x2a0
 __mem_cgroup_charge+0x15/0x80
 folio_prealloc+0x51/0x180
 do_wp_page+0x1231/0x5800
 __handle_mm_fault+0x1033/0x5440
 handle_mm_fault+0x40a/0x8e0
 do_user_addr_fault+0x764/0x1390
 exc_page_fault+0x76/0xf0
 asm_exc_page_fault+0x26/0x30
RIP: 0010:rep_movs_alternative+0x75/0x90
Code: 05 e9 3f 0a 04 00 48 8b 06 48 89 07 48 8d 47 08 48 83 e0 f8 48 29 f8 48 01 c7 48 01 c6 48 29 c1 48 89 c8 48 c1 e9 03 83 e0 07 <f3> 48 a5 89 c1 85 c9 75 91 e9 0d 0a 04 00 48 8d 0c c8 eb 86 cc cc
RSP: 0018:ffffc900046bf978 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff8880124e1000 RCX: 00000000000001d0
RDX: 0000000000000000 RSI: ffff8880124e1180 RDI: 00002000000f9000
RBP: ffffc900046bfae8 R08: ffff8880124e1fff R09: 1ffff1100249c3ff
R10: dffffc0000000000 R11: ffffed100249c400 R12: dffffc0000000000
R13: 00000000000f8b80 R14: 00007ffffffff000 R15: 0000000000001000
 _copy_to_iter+0x493/0x1790
 copy_page_to_iter+0x10c/0x1c0
 process_vm_rw+0x7b4/0xaf0
 __x64_sys_process_vm_readv+0xe0/0x100
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8b24b8ec29
RSP: 002b:00007f8b25a3a038 EFLAGS: 00000246 ORIG_RAX: 0000000000000136
RAX: ffffffffffffffda RBX: 00007f8b24dd5fa0 RCX: 00007f8b24b8ec29
RDX: 0000000000000002 RSI: 0000200000008400 RDI: 000000000000004a
RBP: 00007f8b24c11e41 R08: 0000000000000286 R09: 0000000000000000
R10: 0000200000008640 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f8b24dd6038 R14: 00007f8b24dd5fa0 R15: 00007ffe7a7ea5e8
 </TASK>
rcu: rcu_preempt kthread starved for 10510 jiffies! g10425 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:27160 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00004000
Call Trace:
 <TASK>
 __schedule+0x1798/0x4cc0
 schedule+0x165/0x360
 schedule_timeout+0x12b/0x270
 rcu_gp_fqs_loop+0x301/0x1540
 rcu_gp_kthread+0x99/0x390
 kthread+0x711/0x8a0
 ret_from_fork+0x439/0x7d0
 ret_from_fork_asm+0x1a/0x30
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 UID: 0 PID: 6228 Comm: syz.0.63 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:copy_fpstate_to_sigframe+0x6d0/0xce0
Code: d9 80 e1 07 80 c1 03 38 c1 0f 8c f9 fb ff ff 48 89 df e8 13 8f b9 00 e9 ec fb ff ff f3 0f 1e fa e8 45 0e 56 00 e9 5a fd ff ff <f3> 0f 1e fa e8 37 0e 56 00 48 c7 c7 20 89 45 8b be 3c 00 00 00 e8
RSP: 0018:ffffc9000430f920 EFLAGS: 00000202
RAX: ffff888021b317a4 RBX: ffff888021b31940 RCX: ffffffff81680511
RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffff888021b30000
RBP: ffffc9000430faf0 R08: ffff888021b30007 R09: 1ffff11004366000
R10: dffffc0000000000 R11: ffffed1004366001 R12: ffffc9000430fa10
R13: dffffc0000000000 R14: 00007fa3cc1ede40 R15: ffff888021b30000
FS:  00007fa3cc1ee6c0(0000) GS:ffff8880b8d7e000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000000340 CR3: 0000000112dbc000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 get_sigframe+0x58d/0x7d0
 x64_setup_rt_frame+0x15b/0xd40
 arch_do_signal_or_restart+0x3d7/0x750
 exit_to_user_mode_loop+0x75/0x110
 do_syscall_64+0x2bd/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa3cdf8ec27
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:00007fa3cc1ee0e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: 00000000000000ca RBX: 00007fa3ce1d5fa8 RCX: 00007fa3cdf8ec29
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007fa3ce1d5fa8
RBP: 00007fa3ce1d5fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fa3ce1d6038 R14: 00007ffcd6f01c60 R15: 00007ffcd6f01d48
 </TASK>
