rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5831/1:b..l rcu: (detected by 0, t=10502 jiffies, g=9893, q=233 ncpus=2) task:modprobe state:R running task stack:26704 pid:5831 ppid:5549 flags:0x00000000 Call Trace: context_switch kernel/sched/core.c:5301 [inline] __schedule+0x25d0/0x5a70 kernel/sched/core.c:6619 preempt_schedule_irq+0x52/0xa0 kernel/sched/core.c:6931 irqentry_exit+0x35/0x80 kernel/entry/common.c:433 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:649 RIP: 0010:mas_safe_pivot lib/maple_tree.c:701 [inline] RIP: 0010:mas_validate_limits lib/maple_tree.c:7019 [inline] RIP: 0010:mt_validate+0x1166/0x3360 lib/maple_tree.c:7143 Code: e3 0f 87 a9 1d 00 00 48 8b 44 24 18 0f b6 00 3a 44 24 20 7f 08 84 c0 0f 85 84 1d 00 00 48 8b 04 24 89 df 0f b6 a8 40 1d 89 8b <89> ee e8 33 cc cc f7 40 38 dd 0f 86 f3 04 00 00 e8 35 d0 cc f7 4c RSP: 0018:ffffc9000aec7968 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 000000000000000b RCX: 0000000000000000 RDX: ffff888026250000 RSI: ffffffff89b4ec65 RDI: 000000000000000b RBP: 000000000000000f R08: 0000000000000004 R09: 0000000000000010 R10: 000000000000000b R11: 0000000000000000 R12: 000000000000000b R13: dffffc0000000000 R14: 00007fc0c5924fff R15: ffff88802b695c60 validate_mm_mt+0xa7/0x1b0 mm/mmap.c:295 __split_vma+0x2a/0x5e0 mm/mmap.c:2203 split_vma+0xa3/0xe0 mm/mmap.c:2273 mprotect_fixup+0x6f2/0x930 mm/mprotect.c:663 do_mprotect_pkey+0x6fd/0xa70 mm/mprotect.c:822 __do_sys_mprotect mm/mprotect.c:849 [inline] __se_sys_mprotect mm/mprotect.c:846 [inline] __x64_sys_mprotect+0x78/0xb0 mm/mprotect.c:846 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7fc0c5be8297 RSP: 002b:00007ffd3c7ebd88 EFLAGS: 00000206 ORIG_RAX: 000000000000000a RAX: ffffffffffffffda RBX: 00007fc0c5bc6a00 RCX: 00007fc0c5be8297 RDX: 0000000000000001 RSI: 0000000000001000 RDI: 00007fc0c5940000 RBP: 00007ffd3c7ebea0 R08: 0000000000000000 R09: 00007fc0c5a39310 R10: 00007fc0c5940d78 R11: 0000000000000206 R12: 00007fc0c5bc6a00 R13: 0000000000000007 R14: 0000003f00000007 R15: 00007fc0c592ad90 rcu: rcu_preempt kthread starved for 10514 jiffies! g9893 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:28672 pid:16 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5301 [inline] __schedule+0x25d0/0x5a70 kernel/sched/core.c:6619 schedule+0xde/0x1b0 kernel/sched/core.c:6695 schedule_timeout+0x14e/0x2a0 kernel/time/timer.c:2167 rcu_gp_fqs_loop+0x190/0x910 kernel/rcu/tree.c:1609 rcu_gp_kthread+0x23a/0x360 kernel/rcu/tree.c:1808 kthread+0x2e8/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 rcu: Stack dump where RCU GP kthread last ran: CPU: 0 PID: 5855 Comm: syz-executor.1 Not tainted 6.2.0-rc3-next-20230112-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022 RIP: 0010:lock_acquire.part.0+0x154/0x350 kernel/locking/lockdep.c:5634 Code: b8 ff ff ff ff 65 0f c1 05 79 68 9e 7e 83 f8 01 0f 85 ac 01 00 00 9c 58 f6 c4 02 0f 85 bf 01 00 00 48 85 ed 0f 85 92 01 00 00 <48> b8 00 00 00 00 00 fc ff df 48 01 c3 48 c7 03 00 00 00 00 48 c7 RSP: 0018:ffffc9000b1378d8 EFLAGS: 00000206 RAX: 0000000000000046 RBX: 1ffff92001626f1c RCX: fe1fcf78a240e76e RDX: 1ffff11004f434ee RSI: 0000000000000001 RDI: 0000000000000000 RBP: 0000000000000200 R08: 0000000000000000 R09: ffffffff91353b47 R10: fffffbfff226a768 R11: 0000000000094001 R12: 0000000000000002 R13: 0000000000000000 R14: 0000000000000000 R15: ffffffff8c793fc0 FS: 00007f11f7740700(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fdf5d9fe718 CR3: 000000002985b000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_lock_acquire include/linux/rcupdate.h:327 [inline] rcu_read_lock include/linux/rcupdate.h:773 [inline] percpu_ref_tryget_many include/linux/percpu-refcount.h:241 [inline] percpu_ref_tryget include/linux/percpu-refcount.h:266 [inline] obj_cgroup_tryget include/linux/memcontrol.h:785 [inline] __get_obj_cgroup_from_memcg+0x55/0x290 mm/memcontrol.c:3014 get_obj_cgroup_from_current+0x11a/0x260 mm/memcontrol.c:3034 memcg_slab_pre_alloc_hook mm/slab.h:503 [inline] slab_pre_alloc_hook mm/slab.h:733 [inline] slab_alloc_node mm/slub.c:3434 [inline] __kmem_cache_alloc_node+0x7c/0x330 mm/slub.c:3491 kmalloc_trace+0x26/0x60 mm/slab_common.c:1061 kmalloc include/linux/slab.h:580 [inline] io_cqring_event_overflow+0x10b/0x850 io_uring/io_uring.c:761 io_req_cqe_overflow io_uring/io_uring.c:795 [inline] __io_submit_flush_completions+0x671/0x940 io_uring/io_uring.c:1489 io_submit_flush_completions io_uring/io_uring.c:173 [inline] ctx_flush_and_put+0x13c/0x210 io_uring/io_uring.c:1142 tctx_task_work+0x1af/0x530 io_uring/io_uring.c:1233 task_work_run+0x16f/0x270 kernel/task_work.c:179 get_signal+0x1c7/0x24f0 kernel/signal.c:2635 arch_do_signal_or_restart+0x79/0x5c0 arch/x86/kernel/signal.c:306 exit_to_user_mode_loop kernel/entry/common.c:168 [inline] exit_to_user_mode_prepare+0x11f/0x240 kernel/entry/common.c:204 __syscall_exit_to_user_mode_work kernel/entry/common.c:286 [inline] syscall_exit_to_user_mode+0x1d/0x50 kernel/entry/common.c:297 do_syscall_64+0x46/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f11f6a8c0c9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 00 00 90 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 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f11f7740218 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: 0000000000000000 RBX: 00007f11f6bac1f8 RCX: 00007f11f6a8c0c9 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f11f6bac1f8 RBP: 00007f11f6bac1f0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f11f6bac1fc R13: 00007fffe07ed38f R14: 00007f11f7740300 R15: 0000000000022000