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BUG: KCSAN: data-race in lookup_fast / shrink_dentry_list

write to 0xffff888120ba8c00 of 4 bytes by task 19253 on cpu 0:
 d_lru_del fs/dcache.c:410 [inline]
 __dput_to_list fs/dcache.c:891 [inline]
 shrink_dentry_list+0x2e5/0x530 fs/dcache.c:1140
 shrink_dcache_parent+0x4d/0x3f0 fs/dcache.c:1568
 d_invalidate+0x6e/0x1a0 fs/dcache.c:1677
 lookup_fast+0x2ed/0x370 fs/namei.c:1509
 walk_component+0x5c/0x350 fs/namei.c:1856
 link_path_walk+0x462/0x730 fs/namei.c:2179
 path_openat+0x199/0x20c0 fs/namei.c:3356
 do_filp_open+0xbd/0x1d0 fs/namei.c:3387
 do_sys_openat2+0x33b/0x500 fs/open.c:1174
 do_sys_open fs/open.c:1190 [inline]
 __do_sys_open fs/open.c:1198 [inline]
 __se_sys_open fs/open.c:1194 [inline]
 __x64_sys_open+0xe2/0x110 fs/open.c:1194
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff888120ba8c00 of 4 bytes by task 19264 on cpu 1:
 d_revalidate fs/namei.c:767 [inline]
 lookup_fast+0x7b/0x370 fs/namei.c:1505
 walk_component+0x5c/0x350 fs/namei.c:1856
 link_path_walk+0x462/0x730 fs/namei.c:2179
 path_openat+0x199/0x20c0 fs/namei.c:3356
 do_filp_open+0xbd/0x1d0 fs/namei.c:3387
 do_sys_openat2+0x33b/0x500 fs/open.c:1174
 do_sys_open fs/open.c:1190 [inline]
 __do_sys_open fs/open.c:1198 [inline]
 __se_sys_open fs/open.c:1194 [inline]
 __x64_sys_open+0xe2/0x110 fs/open.c:1194
 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: 19264 Comm: systemd-udevd Not tainted 5.8.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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