rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P26363/1:b..l
rcu: 	(detected by 1, t=10503 jiffies, g=188641, q=688 ncpus=2)
task:syz.2.5236      state:R  running task     stack:25888 pid:26363 tgid:26361 ppid:18165  task_flags:0x40054c flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5260 [inline]
 __schedule+0x1522/0x51d0 kernel/sched/core.c:6867
 preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7194
 irqentry_exit+0x597/0x620 kernel/entry/common.c:216
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:unwind_next_frame+0xeb2/0x23c0 arch/x86/kernel/unwind_orc.c:-1
Code: 4c 8b 64 24 48 74 08 48 89 df e8 49 2b b7 00 48 8b 44 24 18 48 89 03 ba 10 00 00 00 4c 89 e7 31 f6 e8 12 2d b7 00 48 8b 14 24 <e9> ca 04 00 00 4c 89 64 24 18 4d 8d 6e 08 4c 89 e8 48 c1 e8 03 48
RSP: 0018:ffffc900154f7358 EFLAGS: 00000246
RAX: ffffc900154f7478 RBX: ffffc900154f7460 RCX: 0000000000000000
RDX: ffffffff90838b3c RSI: 0000000000000000 RDI: ffffc900154f7488
RBP: dffffc0000000000 R08: ffffc900154f7487 R09: 0000000000000000
R10: ffffc900154f7478 R11: fffff52002a9ee91 R12: ffffc900154f7478
R13: 1ffff92002a9ee87 R14: ffffc900154f7428 R15: ffffc900154f7470
 arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122
 kasan_save_stack+0x3e/0x60 mm/kasan/common.c:57
 kasan_record_aux_stack+0xbd/0xd0 mm/kasan/generic.c:556
 __call_rcu_common kernel/rcu/tree.c:3119 [inline]
 call_rcu+0xee/0x890 kernel/rcu/tree.c:3239
 slab_free_hook mm/slub.c:2504 [inline]
 slab_free mm/slub.c:6674 [inline]
 kmem_cache_free+0x481/0x610 mm/slub.c:6789
 exit_mmap+0x544/0xb30 mm/mmap.c:1302
 __mmput+0x118/0x430 kernel/fork.c:1173
 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:41 [inline]
 exit_to_user_mode_loop+0x86/0x480 kernel/entry/common.c:75
 __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: 0033:0x7f309019aeb9
RSP: 002b:00007f30910a4fd8 EFLAGS: 00000206 ORIG_RAX: 0000000000000038
RAX: 0000000000000657 RBX: 00007f3090416090 RCX: 00007f309019aeb9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000b23e0000
RBP: 00007f3090208c1f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 00007f3090416128 R14: 00007f3090416090 R15: 00007f309053fa48
 </TASK>