rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P6022/1:b..l P17485/1:b..l
rcu: 	(detected by 1, t=10503 jiffies, g=263969, q=1481 ncpus=2)
task:syz.0.18537     state:R  running task     stack:26872 pid:17485 tgid:17485 ppid:6022   task_flags:0x40044c flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5295 [inline]
 __schedule+0x1539/0x5080 kernel/sched/core.c:6907
 preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7234
 irqentry_exit+0x599/0x620 kernel/entry/common.c:239
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lock_acquire+0x221/0x330 kernel/locking/lockdep.c:5872
Code: ff ff ff e8 01 ad 0b 0a f7 44 24 08 00 02 00 00 0f 84 3a ff ff ff 65 48 8b 05 1b 7d 9c 11 48 3b 44 24 58 75 33 fb 48 83 c4 60 <5b> 41 5c 41 5d 41 5e 41 5f 5d e9 40 8f 0e 0a cc 48 8d 3d b8 ea 94
RSP: 0018:ffffc900047f7258 EFLAGS: 00000282
RAX: 683ff399564fbb00 RBX: 0000000000000000 RCX: 0000000000000046
RDX: 000000002ad94000 RSI: ffffffff8e27522c RDI: ffffffff8c298200
RBP: ffffffff81768295 R08: ffffffff81768295 R09: ffffffff8e960160
R10: ffffc900047f73b8 R11: ffffffff81b07c90 R12: 0000000000000002
R13: ffffffff8e960160 R14: 0000000000000000 R15: 0000000000000246
 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+0xc2/0x23c0 arch/x86/kernel/unwind_orc.c:495
 arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:57 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
 poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
 __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:415
 kasan_kmalloc include/linux/kasan.h:263 [inline]
 __kmalloc_cache_noprof+0x31c/0x660 mm/slub.c:5294
 kmalloc_noprof include/linux/slab.h:962 [inline]
 slab_free_hook mm/slub.c:2619 [inline]
 slab_free mm/slub.c:6079 [inline]
 kmem_cache_free+0x154/0x610 mm/slub.c:6205
 tear_down_vmas+0x312/0x520 mm/mmap.c:1264
 exit_mmap+0x4a3/0x9c0 mm/mmap.c:1322
 __mmput+0x118/0x430 kernel/fork.c:1174
 exit_mm+0x168/0x220 kernel/exit.c:581
 do_exit+0x62e/0x2310 kernel/exit.c:959
 do_group_exit+0x21b/0x2d0 kernel/exit.c:1112
 get_signal+0x1284/0x1330 kernel/signal.c:3034
 arch_do_signal_or_restart+0xbc/0x830 arch/x86/kernel/signal.c:337
 __exit_to_user_mode_loop kernel/entry/common.c:64 [inline]
 exit_to_user_mode_loop+0x86/0x480 kernel/entry/common.c:98
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline]
 do_syscall_64+0x2b7/0xf80 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f9b1995b78e
RSP: 002b:00007f9b1a816f58 EFLAGS: 00000246 ORIG_RAX: 00000000000000e6
RAX: fffffffffffffdfc RBX: 00007f9b1a8176c0 RCX: 00007f9b1995b78e
RDX: 00007f9b1a816fb0 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f9b19a08c1f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f9b19c16038 R14: 00007f9b19c15fa0 R15: 00007fff52d51fc8
 </TASK>
task:syz-executor    state:R  running task     stack:20520 pid:6022  tgid:6022  ppid:1      task_flags:0x40054c flags:0x00080003
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5295 [inline]
 __schedule+0x1539/0x5080 kernel/sched/core.c:6907
 preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:7091
 preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
 __raw_read_unlock include/linux/rwlock_api_smp.h:254 [inline]
 _raw_read_unlock+0x3f/0x50 kernel/locking/spinlock.c:260
 zap_pid_ns_processes+0x2c9/0x5f0 kernel/pid_namespace.c:233
 find_child_reaper kernel/exit.c:622 [inline]
 forget_original_parent kernel/exit.c:706 [inline]
 exit_notify kernel/exit.c:743 [inline]
 do_exit+0x1eff/0x2310 kernel/exit.c:983
 do_group_exit+0x21b/0x2d0 kernel/exit.c:1112
 get_signal+0x1284/0x1330 kernel/signal.c:3034
 arch_do_signal_or_restart+0xbc/0x830 arch/x86/kernel/signal.c:337
 __exit_to_user_mode_loop kernel/entry/common.c:64 [inline]
 exit_to_user_mode_loop+0x86/0x480 kernel/entry/common.c:98
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline]
 do_syscall_64+0x2b7/0xf80 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f9b1999c747
RSP: 002b:00007fff52d51c68 EFLAGS: 00000202 ORIG_RAX: 0000000000000029
RAX: 0000000000000003 RBX: 0000000000000003 RCX: 00007f9b1999c747
RDX: 0000000000000006 RSI: 0000000000000001 RDI: 0000000000000002
RBP: 00007fff52d5236c R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 000000000000173e
R13: 0000000000000061 R14: 0000000000131f9e R15: 00007fff52d523c0
 </TASK>