syzbot

rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P3689/2:b..l
	(detected by 0, t=10503 jiffies, g=6525, q=31)
task:syz-executor.2  state:R  running task     stack:28128 pid: 3689 ppid:  3522 flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5030 [inline]
 __schedule+0x12c4/0x45b0 kernel/sched/core.c:6376
 preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6780
 irqentry_exit+0x53/0x80 kernel/entry/common.c:432
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:lock_acquire+0x252/0x4f0 kernel/locking/lockdep.c:5627
Code: 2b 00 74 08 4c 89 f7 e8 fc 7c 67 00 f6 44 24 61 02 0f 85 84 01 00 00 41 f7 c7 00 02 00 00 74 01 fb 48 c7 44 24 40 0e 36 e0 45 <4b> c7 44 25 00 00 00 00 00 43 c7 44 25 09 00 00 00 00 43 c7 44 25
RSP: 0018:ffffc90003d97880 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 1ffff920007b2f1c RCX: 1ffff920007b2ebc
RDX: dffffc0000000000 RSI: ffffffff8a8b3c20 RDI: ffffffff8ad8f680
RBP: ffffc90003d979d8 R08: dffffc0000000000 R09: fffffbfff1f7f019
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff920007b2f18
R13: dffffc0000000000 R14: ffffc90003d978e0 R15: 0000000000000246
 rcu_lock_acquire+0x20/0x30 include/linux/rcupdate.h:312
 rcu_read_lock include/linux/rcupdate.h:739 [inline]
 percpu_ref_tryget_many include/linux/percpu-refcount.h:241 [inline]
 percpu_ref_tryget+0x10/0x140 include/linux/percpu-refcount.h:266
 css_tryget include/linux/cgroup.h:355 [inline]
 get_mem_cgroup_from_objcg+0xa3/0x120 mm/memcontrol.c:2812
 obj_cgroup_charge_pages+0x99/0x1d0 mm/memcontrol.c:3013
 obj_cgroup_charge+0x19e/0x390 mm/memcontrol.c:3296
 memcg_slab_pre_alloc_hook mm/slab.h:287 [inline]
 slab_pre_alloc_hook+0xa6/0xc0 mm/slab.h:497
 slab_alloc_node mm/slub.c:3134 [inline]
 slab_alloc mm/slub.c:3228 [inline]
 kmem_cache_alloc+0x3f/0x280 mm/slub.c:3233
 sk_prot_alloc+0x58/0x200 net/core/sock.c:1857
 sk_alloc+0x35/0x310 net/core/sock.c:1916
 unix_create1+0xb4/0x5d0
 unix_create+0x146/0x1f0 net/unix/af_unix.c:935
 __sock_create+0x460/0x8d0 net/socket.c:1486
 sock_create net/socket.c:1537 [inline]
 __sys_socketpair+0x335/0x700 net/socket.c:1641
 __do_sys_socketpair net/socket.c:1690 [inline]
 __se_sys_socketpair net/socket.c:1687 [inline]
 __x64_sys_socketpair+0x97/0xb0 net/socket.c:1687
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f3ddc3f6ee9
RSP: 002b:00007f3dda96a0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000035
RAX: ffffffffffffffda RBX: 00007f3ddc525f80 RCX: 00007f3ddc3f6ee9
RDX: 0000000000000000 RSI: 0000000000000005 RDI: 0000000000000001
RBP: 00007f3ddc44349e R08: 0000000000000000 R09: 0000000000000000
R10: 00000000200000c0 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007f3ddc525f80 R15: 00007fff7bc19688
 </TASK>
rcu: rcu_preempt kthread starved for 10537 jiffies! g6525 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:27000 pid:   15 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5030 [inline]
 __schedule+0x12c4/0x45b0 kernel/sched/core.c:6376
 preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6780
 irqentry_exit+0x53/0x80 kernel/entry/common.c:432
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:schedule+0x10a/0x1f0 kernel/sched/core.c:6458
Code: a3 f7 49 8b 07 4c 39 f8 74 0d 4c 89 f7 be 01 00 00 00 e8 a9 c2 c6 f9 4c 89 eb 48 c1 eb 03 eb 0a 49 f7 45 00 08 00 00 00 74 39 <bf> 01 00 00 00 e8 7c 20 31 f7 31 ff e8 35 b9 ff ff bf 01 00 00 00
RSP: 0018:ffffc90000d47b70 EFLAGS: 00000202
RAX: 0000000000000001 RBX: 1ffff11027fc4770 RCX: ffffffff8a264012
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffff88813fe23b80
RBP: ffffc90000d47c90 R08: dffffc0000000000 R09: ffffed1027fc4771
R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000
R13: ffff88813fe23b80 R14: 0000000000000000 R15: 00000000ffffa395
 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1914
 rcu_gp_fqs_loop+0x2bf/0x1080 kernel/rcu/tree.c:1972
 rcu_gp_kthread+0xa4/0x360 kernel/rcu/tree.c:2145
 kthread+0x3f6/0x4f0 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:300
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
NMI backtrace for cpu 0
CPU: 0 PID: 3691 Comm: syz-executor.3 Not tainted 5.15.159-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x46a/0x4a0 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x181/0x2a0 lib/nmi_backtrace.c:62
 trigger_single_cpu_backtrace include/linux/nmi.h:166 [inline]
 rcu_check_gp_kthread_starvation+0x1d2/0x240 kernel/rcu/tree_stall.h:487
 print_other_cpu_stall+0x137a/0x14d0 kernel/rcu/tree_stall.h:592
 check_cpu_stall kernel/rcu/tree_stall.h:745 [inline]
 rcu_pending kernel/rcu/tree.c:3932 [inline]
 rcu_sched_clock_irq+0xa38/0x1150 kernel/rcu/tree.c:2619
 update_process_times+0x196/0x200 kernel/time/timer.c:1818
 tick_sched_handle kernel/time/tick-sched.c:254 [inline]
 tick_sched_timer+0x386/0x550 kernel/time/tick-sched.c:1473
 __run_hrtimer kernel/time/hrtimer.c:1686 [inline]
 __hrtimer_run_queues+0x55b/0xcf0 kernel/time/hrtimer.c:1750
 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1812
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1085 [inline]
 __sysvec_apic_timer_interrupt+0x139/0x470 arch/x86/kernel/apic/apic.c:1102
 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1096
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:lock_acquire+0x252/0x4f0 kernel/locking/lockdep.c:5627
Code: 2b 00 74 08 4c 89 f7 e8 fc 7c 67 00 f6 44 24 61 02 0f 85 84 01 00 00 41 f7 c7 00 02 00 00 74 01 fb 48 c7 44 24 40 0e 36 e0 45 <4b> c7 44 25 00 00 00 00 00 43 c7 44 25 09 00 00 00 00 43 c7 44 25
RSP: 0018:ffffc900010efaa0 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 1ffff9200021df60 RCX: ffffffff81636502
RDX: dffffc0000000000 RSI: ffffffff8a8b3c20 RDI: ffffffff8ad8f680
RBP: ffffc900010efbe8 R08: dffffc0000000000 R09: fffffbfff1f7f01f
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff9200021df5c
R13: dffffc0000000000 R14: ffffc900010efb00 R15: 0000000000000246
 __might_fault+0xb4/0x110 mm/memory.c:5328
 _copy_from_user+0x28/0x170 lib/usercopy.c:14
 copy_from_user include/linux/uaccess.h:192 [inline]
 restore_sigcontext+0xce/0x710 arch/x86/kernel/signal.c:91
 __do_sys_rt_sigreturn+0x190/0x250 arch/x86/kernel/signal.c:674
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f636af41339
Code: 64 c7 00 16 00 00 00 b8 ff ff ff ff c3 0f 1f 40 00 90 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 c7 c0 0f 00 00 00 0f 05 <0f> 1f 80 00 00 00 00 48 81 ec 48 01 00 00 49 89 d0 64 48 8b 04 25
RSP: 002b:00007f63694cfbc0 EFLAGS: 00000202 ORIG_RAX: 000000000000000f
RAX: ffffffffffffffda RBX: 00007f636b0ad058 RCX: 00007f636af41339
RDX: 00007f63694cfbc0 RSI: 00007f63694cfcf0 RDI: 0000000000000021
RBP: 00007f636b0ad050 R08: 00007f63694d06c0 R09: 00007f63694d06c0
R10: 0000000000000000 R11: 0000000000000202 R12: 00007f636b0ad05c
R13: 000000000000006e R14: 00007ffe1827c330 R15: 00007ffe1827c418
 </TASK>
sched: RT throttling activated