rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P17103/1:b..l P5833/1:b..l rcu: (detected by 1, t=10503 jiffies, g=66817, q=1319317 ncpus=2) task:syz-executor state:R running task stack:19992 pid:5833 tgid:5833 ppid:5827 task_flags:0x400140 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5396 [inline] __schedule+0x16f5/0x4d00 kernel/sched/core.c:6785 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7108 irqentry_exit+0x6f/0x90 kernel/entry/common.c:307 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:trace_lock_release include/trace/events/lock.h:69 [inline] RIP: 0010:lock_release+0x4d/0x3e0 kernel/locking/lockdep.c:5882 Code: 24 28 0f 1f 44 00 00 65 8b 05 63 9a fe 10 83 f8 08 0f 83 9a 02 00 00 89 c0 48 0f a3 05 0c cd 02 0e 73 16 e8 55 e0 08 00 84 c0 <75> 0d f6 05 57 b8 ec 0d 01 0f 84 ad 02 00 00 83 3d 2d fe 02 0e 00 RSP: 0018:ffffc90002ef7770 EFLAGS: 00000202 RAX: 0000000000000001 RBX: ffffffff903f3501 RCX: c8588aa453457b00 RDX: ffffc90002ef7801 RSI: ffffffff8be28360 RDI: ffffffff8be28320 RBP: dffffc0000000000 R08: ffffc90002ef7e30 R09: ffffc90002ef78f8 R10: dffffc0000000000 R11: fffff520005def21 R12: ffffc90002ef7e40 R13: ffffffff81729de5 R14: ffffffff8e13f060 R15: ffffffff81729de5 rcu_lock_release include/linux/rcupdate.h:341 [inline] rcu_read_unlock include/linux/rcupdate.h:871 [inline] class_rcu_destructor include/linux/rcupdate.h:1155 [inline] unwind_next_frame+0x19a9/0x2390 arch/x86/kernel/unwind_orc.c:680 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 save_stack+0xf5/0x1f0 mm/page_owner.c:156 __reset_page_owner+0x71/0x1f0 mm/page_owner.c:308 reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1248 [inline] __free_frozen_pages+0xc71/0xe70 mm/page_alloc.c:2706 discard_slab mm/slub.c:2717 [inline] __put_partials+0x161/0x1c0 mm/slub.c:3186 put_cpu_partial+0x17c/0x250 mm/slub.c:3261 __slab_free+0x2f7/0x400 mm/slub.c:4513 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x97/0x140 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:329 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4148 [inline] slab_alloc_node mm/slub.c:4197 [inline] kmem_cache_alloc_noprof+0x1c1/0x3c0 mm/slub.c:4204 getname_flags+0xb8/0x540 fs/namei.c:146 user_path_at+0x24/0x60 fs/namei.c:3126 ksys_umount fs/namespace.c:2147 [inline] __do_sys_umount fs/namespace.c:2155 [inline] __se_sys_umount fs/namespace.c:2153 [inline] __x64_sys_umount+0xee/0x160 fs/namespace.c:2153 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f204a18fc57 RSP: 002b:00007ffcc5c55368 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: ffffffffffffffda RBX: 00007f204a210925 RCX: 00007f204a18fc57 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffcc5c564b0 RBP: 00007ffcc5c5649c R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffcc5c564b0 R13: 00007f204a210925 R14: 000000000008863c R15: 00007ffcc5c564f0 task:syz.4.4121 state:X running task stack:25672 pid:17103 tgid:17102 ppid:0 task_flags:0x40044c flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5396 [inline] __schedule+0x16f5/0x4d00 kernel/sched/core.c:6785 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7108 irqentry_exit+0x6f/0x90 kernel/entry/common.c:307 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:debug_lockdep_rcu_enabled+0x0/0x40 kernel/rcu/update.c:319 Code: 56 1a 1e f6 90 0f 0b 90 90 90 eb c4 cc cc cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 31 c0 83 3d 27 24 3b 04 00 74 1e 83 3d 4a 54 3b 04 00 RSP: 0018:ffffc9000b8e7a60 EFLAGS: 00000202 RAX: 00000000f1f42801 RBX: ffff888076ef9610 RCX: bcae24bfb7d59f00 RDX: 0000000000000001 RSI: ffffffff8db6e1b9 RDI: ffff888030d6da00 RBP: 1ffffffff1f42886 R08: 0000000000000000 R09: ffffffff822c71a5 R10: dffffc0000000000 R11: ffffed10036dd131 R12: ffff88807a4ea74c R13: dffffc0000000000 R14: 1ffff1100eddf2c2 R15: ffff88807a4ea700 rcu_read_unlock include/linux/rcupdate.h:869 [inline] get_mem_cgroup_from_objcg+0x15d/0x1d0 include/linux/memcontrol.h:511 obj_cgroup_uncharge_pages mm/memcontrol.c:2777 [inline] __memcg_kmem_uncharge_page+0x85/0x170 mm/memcontrol.c:2870 do_exit+0x1823/0x22e0 kernel/exit.c:996 do_group_exit+0x21c/0x2d0 kernel/exit.c:1104 get_signal+0x1286/0x1340 kernel/signal.c:3034 arch_do_signal_or_restart+0x9a/0x750 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop+0x75/0x110 kernel/entry/common.c:111 exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline] do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fc89e58e52b RSP: 002b:00007fc89f457dc0 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: 0000000000000000 RBX: 0000000000000004 RCX: 00007fc89e58e52b RDX: 0000000000000003 RSI: 0000000000004c00 RDI: 0000000000000004 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000251 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003 R13: 00007fc89f457ef0 R14: 00007fc89f457eb0 R15: 00007fc893e00000