syzbot

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BUG: KCSAN: data-race in __dentry_kill / d_set_d_op

write to 0xffff88809d7c1c00 of 4 bytes by task 16002 on cpu 0:
 d_set_d_op+0x16f/0x210 fs/dcache.c:1856
 simple_lookup fs/libfs.c:71 [inline]
 simple_lookup+0x9f/0xb0 fs/libfs.c:66
 lookup_open fs/namei.c:3060 [inline]
 open_last_lookups fs/namei.c:3155 [inline]
 path_openat+0xb33/0x23d0 fs/namei.c:3343
 do_filp_open+0x11e/0x1b0 fs/namei.c:3373
 do_sys_openat2+0x52e/0x680 fs/open.c:1148
 do_sys_open+0xa2/0x110 fs/open.c:1164
 ksys_open include/linux/syscalls.h:1386 [inline]
 __do_sys_open fs/open.c:1170 [inline]
 __se_sys_open fs/open.c:1168 [inline]
 __x64_sys_open+0x50/0x60 fs/open.c:1168
 do_syscall_64+0xc7/0x3b0 arch/x86/entry/common.c:295
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff88809d7c1c00 of 4 bytes by task 17539 on cpu 1:
 dentry_unlist fs/dcache.c:544 [inline]
 __dentry_kill+0x1b4/0x3b0 fs/dcache.c:575
 dentry_kill fs/dcache.c:698 [inline]
 dput+0x399/0x700 fs/dcache.c:859
 handle_mounts fs/namei.c:1375 [inline]
 step_into+0x8a3/0x1090 fs/namei.c:1676
 open_last_lookups fs/namei.c:3178 [inline]
 path_openat+0x34e/0x23d0 fs/namei.c:3343
 do_filp_open+0x11e/0x1b0 fs/namei.c:3373
 do_sys_openat2+0x52e/0x680 fs/open.c:1148
 do_sys_open+0xa2/0x110 fs/open.c:1164
 ksys_open include/linux/syscalls.h:1386 [inline]
 __do_sys_open fs/open.c:1170 [inline]
 __se_sys_open fs/open.c:1168 [inline]
 __x64_sys_open+0x50/0x60 fs/open.c:1168
 do_syscall_64+0xc7/0x3b0 arch/x86/entry/common.c:295
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 17539 Comm: syz-executor.3 Not tainted 5.7.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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