syzbot

==================================================================
BUG: KCSAN: data-race in do_group_exit / mm_release

write to 0xffff8881026771b4 of 4 bytes by task 27288 on cpu 0:
 do_group_exit+0x130/0x170 kernel/exit.c:900
 __do_sys_exit_group+0xb/0x10 kernel/exit.c:917
 __se_sys_exit_group+0x5/0x10 kernel/exit.c:915
 __x64_sys_exit_group+0x16/0x20 kernel/exit.c:915
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff8881026771b4 of 4 bytes by task 27305 on cpu 1:
 mm_release+0x92/0x1c0 kernel/fork.c:1299
 exit_mm_release+0x21/0x30 kernel/fork.c:1323
 exit_mm+0x4b/0x370 kernel/exit.c:438
 do_exit+0x3c2/0x15a0 kernel/exit.c:796
 __do_sys_exit+0xb/0x10 kernel/exit.c:875
 __se_sys_exit+0x5/0x10 kernel/exit.c:873
 __x64_sys_exit+0x16/0x20 kernel/exit.c:873
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 27305 Comm: syz-executor.2 Not tainted 5.10.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================