syzbot

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BUG: KCSAN: data-race in __dentry_kill / d_set_d_op

write to 0xffff88810f6dc000 of 4 bytes by task 11014 on cpu 0:
 d_set_d_op+0x17f/0x220 fs/dcache.c:1908
 simple_lookup+0x78/0x90 fs/libfs.c:74
 lookup_open fs/namei.c:3197 [inline]
 open_last_lookups fs/namei.c:3289 [inline]
 path_openat+0xaca/0x21b0 fs/namei.c:3495
 do_filp_open+0xbd/0x1d0 fs/namei.c:3525
 do_sys_openat2+0xa3/0x250 fs/open.c:1187
 do_sys_open fs/open.c:1203 [inline]
 __do_sys_open fs/open.c:1211 [inline]
 __se_sys_open fs/open.c:1207 [inline]
 __x64_sys_open+0xe2/0x110 fs/open.c:1207
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff88810f6dc000 of 4 bytes by task 11018 on cpu 1:
 dentry_unlist fs/dcache.c:545 [inline]
 __dentry_kill+0x1ef/0x450 fs/dcache.c:576
 dentry_kill fs/dcache.c:693 [inline]
 dput+0x218/0x430 fs/dcache.c:886
 handle_mounts fs/namei.c:1471 [inline]
 step_into+0x442/0xec0 fs/namei.c:1769
 open_last_lookups fs/namei.c:3312 [inline]
 path_openat+0x105e/0x21b0 fs/namei.c:3495
 do_filp_open+0xbd/0x1d0 fs/namei.c:3525
 do_sys_openat2+0xa3/0x250 fs/open.c:1187
 do_sys_open fs/open.c:1203 [inline]
 __do_sys_open fs/open.c:1211 [inline]
 __se_sys_open fs/open.c:1207 [inline]
 __x64_sys_open+0xe2/0x110 fs/open.c:1207
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 11018 Comm: systemd-udevd Not tainted 5.12.0-rc2-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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