==================================================================
BUG: KCSAN: data-race in __d_instantiate / lookup_fast

read-write to 0xffff88813af0c840 of 4 bytes by task 22870 on cpu 1:
 __d_instantiate+0x2cd/0x3b0 fs/dcache.c:2011
 d_instantiate_new+0x5c/0xf0 fs/dcache.c:2055
 ext4_add_nondir+0x161/0x190 fs/ext4/namei.c:2797
 ext4_mknod+0x20f/0x2f0 fs/ext4/namei.c:2871
 vfs_mknod+0x29e/0x2f0 fs/namei.c:3995
 do_mknodat+0x23f/0x3d0
 __do_sys_mknodat fs/namei.c:4073 [inline]
 __se_sys_mknodat fs/namei.c:4070 [inline]
 __x64_sys_mknodat+0x62/0x70 fs/namei.c:4070
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

read to 0xffff88813af0c840 of 4 bytes by task 22871 on cpu 0:
 d_revalidate fs/namei.c:858 [inline]
 lookup_fast+0xd9/0x290 fs/namei.c:1639
 open_last_lookups fs/namei.c:3529 [inline]
 path_openat+0x44c/0x1d10 fs/namei.c:3790
 do_filp_open+0xf6/0x200 fs/namei.c:3820
 do_sys_openat2+0xab/0x110 fs/open.c:1407
 do_sys_open fs/open.c:1422 [inline]
 __do_sys_openat fs/open.c:1438 [inline]
 __se_sys_openat fs/open.c:1433 [inline]
 __x64_sys_openat+0xf3/0x120 fs/open.c:1433
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0x00000000 -> 0x00580040

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 22871 Comm: syz-executor.1 Not tainted 6.5.0-rc6-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023
==================================================================