rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P2/1:b..l P5196/1:b..l rcu: (detected by 1, t=10502 jiffies, g=20897, q=807089 ncpus=2) task:udevd state:R running task stack:24192 pid:5196 tgid:5196 ppid:1 task_flags:0x400140 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5396 [inline] __schedule+0x16a2/0x4cb0 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:lock_acquire+0x175/0x360 kernel/locking/lockdep.c:5875 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 2b 7b fb 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:ffffc90003327550 EFLAGS: 00000206 RAX: 364c7beb90346a00 RBX: 0000000000000000 RCX: 364c7beb90346a00 RDX: 0000000000000000 RSI: ffffffff8db594b7 RDI: ffffffff8be1af40 RBP: ffffffff822cae6a R08: 0000000000000000 R09: ffffffff822cae6a R10: dffffc0000000000 R11: ffffed100699a52a R12: 0000000000000002 R13: ffffffff8e13eda0 R14: 0000000000000000 R15: 0000000000000246 rcu_lock_acquire include/linux/rcupdate.h:331 [inline] rcu_read_lock include/linux/rcupdate.h:841 [inline] __page_table_check_zero+0xd7/0x530 mm/page_table_check.c:138 page_table_check_free include/linux/page_table_check.h:43 [inline] free_pages_prepare mm/page_alloc.c:1249 [inline] __free_frozen_pages+0xc78/0xe60 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_kmalloc+0x22/0xb0 mm/kasan/common.c:385 kasan_kmalloc include/linux/kasan.h:260 [inline] __do_kmalloc_node mm/slub.c:4328 [inline] __kmalloc_noprof+0x27a/0x4f0 mm/slub.c:4340 kmalloc_noprof include/linux/slab.h:909 [inline] kzalloc_noprof include/linux/slab.h:1039 [inline] tomoyo_encode2 security/tomoyo/realpath.c:45 [inline] tomoyo_encode+0x28b/0x550 security/tomoyo/realpath.c:80 tomoyo_realpath_from_path+0x58d/0x5d0 security/tomoyo/realpath.c:283 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_path_perm+0x213/0x4b0 security/tomoyo/file.c:822 security_inode_getattr+0x12f/0x330 security/security.c:2377 vfs_getattr fs/stat.c:259 [inline] vfs_statx_path fs/stat.c:299 [inline] vfs_statx+0x18e/0x550 fs/stat.c:356 vfs_fstatat+0x118/0x170 fs/stat.c:375 __do_sys_newfstatat fs/stat.c:542 [inline] __se_sys_newfstatat fs/stat.c:536 [inline] __x64_sys_newfstatat+0x116/0x190 fs/stat.c:536 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: 0033:0x7fefd5311b0a RSP: 002b:00007ffd1b7a6ec8 EFLAGS: 00000246 ORIG_RAX: 0000000000000106 RAX: ffffffffffffffda RBX: 000055668ff70f50 RCX: 00007fefd5311b0a RDX: 00007ffd1b7a6ed0 RSI: 000055668ff70f50 RDI: 00000000ffffff9c RBP: 000055668ff5fbf0 R08: 00063478c1c69200 R09: 7fffffffffffffff R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffd1b7a6ed0 R13: 000055666e6a4100 R14: 0000000000000000 R15: 0000000000000000 task:kthreadd state:R running task stack:24128 pid:2 tgid:2 ppid:0 task_flags:0x208040 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5396 [inline] __schedule+0x16a2/0x4cb0 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:lock_acquire+0x175/0x360 kernel/locking/lockdep.c:5875 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 2b 7b fb 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:ffffc90000077038 EFLAGS: 00000206 RAX: 2db99814db0c2900 RBX: 0000000000000000 RCX: 2db99814db0c2900 RDX: 0000000000000000 RSI: ffffffff8db594b7 RDI: ffffffff8be1af40 RBP: ffffffff81728de5 R08: 0000000000000000 R09: ffffffff81728de5 R10: ffffc900000771f8 R11: ffffffff81ace8a0 R12: 0000000000000002 R13: ffffffff8e13eda0 R14: 0000000000000000 R15: 0000000000000246 rcu_lock_acquire include/linux/rcupdate.h:331 [inline] rcu_read_lock include/linux/rcupdate.h:841 [inline] class_rcu_constructor include/linux/rcupdate.h:1155 [inline] unwind_next_frame+0xc2/0x2390 arch/x86/kernel/unwind_orc.c:479 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 save_stack+0xf7/0x1f0 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+0xc65/0xe60 mm/page_alloc.c:2706 __slab_free+0x326/0x400 mm/slub.c:4554 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] __kmalloc_cache_node_noprof+0x1c0/0x3d0 mm/slub.c:4367 kmalloc_node_noprof include/linux/slab.h:928 [inline] __get_vm_area_node+0x13f/0x300 mm/vmalloc.c:3168 __vmalloc_node_range_noprof+0x301/0x12f0 mm/vmalloc.c:3845 __vmalloc_node_noprof+0xc2/0x110 mm/vmalloc.c:3948 alloc_thread_stack_node kernel/fork.c:317 [inline] dup_task_struct+0x3e7/0x860 kernel/fork.c:877 copy_process+0x54b/0x3c00 kernel/fork.c:1999 kernel_clone+0x224/0x7f0 kernel/fork.c:2599 kernel_thread+0x10c/0x160 kernel/fork.c:2661 create_kthread kernel/kthread.c:487 [inline] kthreadd+0x575/0x770 kernel/kthread.c:847 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245