rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P17944/1:b..l rcu: (detected by 0, t=10502 jiffies, g=153065, q=924 ncpus=1) task:udevd state:R running task stack:27144 pid:17944 tgid:17944 ppid:5193 task_flags:0x40014c flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5295 [inline] __schedule+0xfee/0x60e0 kernel/sched/core.c:6907 preempt_schedule_irq+0x50/0x90 kernel/sched/core.c:7234 irqentry_exit+0x17b/0x670 kernel/entry/common.c:239 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:lock_acquire+0x5e/0x380 kernel/locking/lockdep.c:5872 Code: 05 7b ae 28 12 83 f8 07 0f 87 f0 00 00 00 48 0f a3 05 46 47 f5 0e 0f 82 c2 02 00 00 8b 35 0e 7b f5 0e 85 f6 0f 85 dd 00 00 00 <48> 8b 44 24 30 65 48 2b 05 1d ae 28 12 0f 85 02 03 00 00 48 83 c4 RSP: 0018:ffffc9000d757620 EFLAGS: 00000206 RAX: 0000000000000046 RBX: 0000000000000000 RCX: 0000000000000001 RDX: 0000000000000000 RSI: ffffffff8de5414a RDI: ffffffff8c1aeb20 RBP: ffffffff8e7e9220 R08: 00000000a1bbbf67 R09: 0000000000000007 R10: 0000000000000200 R11: 0000000000000000 R12: 0000000000000002 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 rcu_lock_acquire include/linux/rcupdate.h:312 [inline] rcu_read_lock include/linux/rcupdate.h:850 [inline] class_rcu_constructor include/linux/rcupdate.h:1193 [inline] unwind_next_frame+0xd1/0x1ea0 arch/x86/kernel/unwind_orc.c:495 arch_stack_walk+0x94/0xf0 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122 kasan_save_stack+0x30/0x50 mm/kasan/common.c:57 kasan_save_track+0x14/0x30 mm/kasan/common.c:78 poison_kmalloc_redzone mm/kasan/common.c:398 [inline] __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:415 kmalloc_noprof include/linux/slab.h:962 [inline] slab_free_hook mm/slub.c:2639 [inline] slab_free mm/slub.c:6124 [inline] kmem_cache_free+0x41f/0x6a0 mm/slub.c:6254 tear_down_vmas+0x2a5/0x600 mm/mmap.c:1264 exit_mmap+0x469/0xa30 mm/mmap.c:1322 __mmput+0x12a/0x410 kernel/fork.c:1174 mmput+0x67/0x80 kernel/fork.c:1197 exit_mm kernel/exit.c:581 [inline] do_exit+0x78a/0x2aa0 kernel/exit.c:959 do_group_exit+0xd5/0x2a0 kernel/exit.c:1112 __do_sys_exit_group kernel/exit.c:1123 [inline] __se_sys_exit_group kernel/exit.c:1121 [inline] __x64_sys_exit_group+0x3e/0x50 kernel/exit.c:1121 x64_sys_call+0x102c/0x1530 arch/x86/include/generated/asm/syscalls_64.h:232 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7ff8d76f16c5 RSP: 002b:00007ffc66523628 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 0000562e7d94ab60 RCX: 00007ff8d76f16c5 RDX: 00000000000000e7 RSI: fffffffffffffe68 RDI: 0000000000000000 RBP: 0000562e7d923910 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffc66523670 R14: 0000000000000000 R15: 0000000000000000