rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5202/1:b..l rcu: (detected by 1, t=10502 jiffies, g=12309, q=1562826 ncpus=2) task:udevd state:R running task stack:24664 pid:5202 tgid:5202 ppid:1 task_flags:0x400140 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5397 [inline] __schedule+0x116a/0x5dd0 kernel/sched/core.c:6786 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7109 irqentry_exit+0x36/0x90 kernel/entry/common.c:307 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:unwind_next_frame+0x1613/0x20a0 arch/x86/kernel/unwind_orc.c:665 Code: 48 c1 ea 03 80 3c 02 00 0f 84 4a f8 ff ff e8 74 50 b6 00 e9 40 f8 ff ff 48 b8 00 00 00 00 00 fc ff df 48 8b 14 24 48 c1 ea 03 <80> 3c 02 00 0f 85 5b 05 00 00 49 8d 7d 08 49 8b 5d 38 48 b8 00 00 RSP: 0018:ffffc9000489f2b0 EFLAGS: 00000a02 RAX: dffffc0000000000 RBX: 0000000000000001 RCX: ffffc900048a0000 RDX: 1ffff92000913e6b RSI: ffffc9000489fa60 RDI: ffffc9000489f360 RBP: ffffc9000489fad0 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000013168 R12: ffffc9000489f370 R13: ffffc9000489f320 R14: ffffc9000489fa90 R15: ffffc9000489f354 arch_stack_walk+0x94/0x100 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122 save_stack+0x160/0x1f0 mm/page_owner.c:156 __reset_page_owner+0x84/0x1a0 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+0x7fe/0x1180 mm/page_alloc.c:2706 discard_slab mm/slub.c:2717 [inline] __put_partials+0x16d/0x1c0 mm/slub.c:3186 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x4d/0x120 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x195/0x1e0 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x69/0x90 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] __do_kmalloc_node mm/slub.c:4327 [inline] __kmalloc_noprof+0x1d4/0x510 mm/slub.c:4340 kmalloc_noprof include/linux/slab.h:909 [inline] tomoyo_realpath_from_path+0xc2/0x6e0 security/tomoyo/realpath.c:251 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_check_open_permission+0x2ab/0x3c0 security/tomoyo/file.c:771 tomoyo_file_open+0x6b/0x90 security/tomoyo/tomoyo.c:334 security_file_open+0x84/0x1e0 security/security.c:3114 do_dentry_open+0x596/0x1c10 fs/open.c:941 vfs_open+0x82/0x3f0 fs/open.c:1094 do_open fs/namei.c:3896 [inline] path_openat+0x1de4/0x2cb0 fs/namei.c:4055 do_filp_open+0x20b/0x470 fs/namei.c:4082 do_sys_openat2+0x11b/0x1d0 fs/open.c:1437 do_sys_open fs/open.c:1452 [inline] __do_sys_openat fs/open.c:1468 [inline] __se_sys_openat fs/open.c:1463 [inline] __x64_sys_openat+0x174/0x210 fs/open.c:1463 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fba0d4a7407 RSP: 002b:00007ffc0d3e50a0 EFLAGS: 00000202 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007fba0dca5880 RCX: 00007fba0d4a7407 RDX: 0000000000080141 RSI: 000055cad4b6402e RDI: ffffffffffffff9c RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000000001a4 R11: 0000000000000202 R12: 00000000ffffffff R13: 00000000ffffffff R14: ffffffffffffffff R15: 0000000000000000