==================================================================
BUG: KCSAN: data-race in do_exit / get_signal

write to 0xffff88810e856064 of 4 bytes by task 12098 on cpu 0:
 get_signal+0xf5a/0x1650 kernel/signal.c:2723
 do_signal+0x25/0x270 arch/x86/kernel/signal.c:810
 exit_to_usermode_loop arch/x86/entry/common.c:235 [inline]
 __prepare_exit_to_usermode+0x127/0x230 arch/x86/entry/common.c:269
 __syscall_return_slowpath+0x47/0x60 arch/x86/entry/common.c:352
 do_syscall_64+0x5d/0xb0 arch/x86/entry/common.c:393
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff88810e856064 of 4 bytes by task 12088 on cpu 1:
 find_alive_thread kernel/exit.c:492 [inline]
 find_new_reaper kernel/exit.c:541 [inline]
 forget_original_parent kernel/exit.c:616 [inline]
 exit_notify kernel/exit.c:649 [inline]
 do_exit+0x810/0x16e0 kernel/exit.c:826
 do_group_exit+0xcb/0x180 kernel/exit.c:903
 get_signal+0x106d/0x1650 kernel/signal.c:2743
 do_signal+0x25/0x270 arch/x86/kernel/signal.c:810
 exit_to_usermode_loop arch/x86/entry/common.c:235 [inline]
 __prepare_exit_to_usermode+0x127/0x230 arch/x86/entry/common.c:269
 __syscall_return_slowpath+0x47/0x60 arch/x86/entry/common.c:352
 do_syscall_64+0x5d/0xb0 arch/x86/entry/common.c:393
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 12088 Comm: syz-executor.0 Not tainted 5.8.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================