syzbot

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BUG: KCSAN: data-race in __d_instantiate / step_into

write to 0xffff88810a585db0 of 8 bytes by task 3948 on cpu 1:
 __d_set_inode_and_type fs/dcache.c:362 [inline]
 __d_instantiate+0x1fe/0x3c0 fs/dcache.c:1877
 d_instantiate+0x59/0x80 fs/dcache.c:1904
 shmem_mknod+0x153/0x180 mm/shmem.c:3693
 shmem_mkdir+0x33/0x70 mm/shmem.c:3736
 vfs_mkdir+0x1f4/0x320 fs/namei.c:4311
 do_mkdirat+0x12f/0x2b0 fs/namei.c:4334
 __do_sys_mkdir fs/namei.c:4354 [inline]
 __se_sys_mkdir fs/namei.c:4352 [inline]
 __x64_sys_mkdir+0x42/0x50 fs/namei.c:4352
 x64_sys_call+0x1b2b/0x2dc0 arch/x86/include/generated/asm/syscalls_64.h:84
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff88810a585db0 of 8 bytes by task 3288 on cpu 0:
 step_into+0x123/0x840 fs/namei.c:1954
 open_last_lookups fs/namei.c:3775 [inline]
 path_openat+0x1234/0x1fa0 fs/namei.c:3984
 do_filp_open+0x107/0x230 fs/namei.c:4014
 do_sys_openat2+0xab/0x120 fs/open.c:1402
 do_sys_open fs/open.c:1417 [inline]
 __do_sys_openat fs/open.c:1433 [inline]
 __se_sys_openat fs/open.c:1428 [inline]
 __x64_sys_openat+0xf3/0x120 fs/open.c:1428
 x64_sys_call+0x2b30/0x2dc0 arch/x86/include/generated/asm/syscalls_64.h:258
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x0000000000000000 -> 0xffff888106dfa078

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 3288 Comm: udevd Tainted: G        W          6.12.0-syzkaller-11677-g2ba9f676d0a2 #0
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
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