[moderation] [mm?] KCSAN: data-race in list_lru_add / list_lru_count_node (10)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 39cd87c4eb2b Linux 6.9-rc2
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=10599d29180000
kernel config: https://syzkaller.appspot.com/x/.config?x=d024e89f7bb376ce
dashboard link: https://syzkaller.appspot.com/bug?extid=93aab41231573c431949
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
CC: [ak...@linux-foundation.org linux-...@vger.kernel.org linu...@kvack.org]

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/b9b2dcffd7d5/disk-39cd87c4.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/5f4981fa60e6/vmlinux-39cd87c4.xz
kernel image: https://storage.googleapis.com/syzbot-assets/691f671f70ad/bzImage-39cd87c4.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+93aab4...@syzkaller.appspotmail.com

==================================================================
BUG: KCSAN: data-race in list_lru_add / list_lru_count_node

read-write to 0xffff888103eea4a0 of 8 bytes by task 13876 on cpu 1:
list_lru_add+0x1f4/0x230 mm/list_lru.c:101
list_lru_add_obj+0xbb/0xd0 mm/list_lru.c:116
d_lru_add+0xa8/0xe0 fs/dcache.c:430
retain_dentry fs/dcache.c:712 [inline]
fast_dput+0x26b/0x2b0 fs/dcache.c:799
dput+0x24/0xd0 fs/dcache.c:839
done_path_create fs/namei.c:3942 [inline]
do_symlinkat+0xee/0x350 fs/namei.c:4512
__do_sys_symlinkat fs/namei.c:4526 [inline]
__se_sys_symlinkat fs/namei.c:4523 [inline]
__x64_sys_symlinkat+0x62/0x70 fs/namei.c:4523
do_syscall_64+0xd3/0x1d0
entry_SYSCALL_64_after_hwframe+0x72/0x7a

read to 0xffff888103eea4a0 of 8 bytes by task 13875 on cpu 0:
list_lru_count_node+0x2c/0x40 mm/list_lru.c:188
list_lru_count include/linux/list_lru.h:165 [inline]
shrink_dcache_sb+0x1bc/0x2a0 fs/dcache.c:1196
reconfigure_super+0x3fe/0x5a0 fs/super.c:1049
do_remount fs/namespace.c:2892 [inline]
path_mount+0x96e/0xb30 fs/namespace.c:3671
do_mount fs/namespace.c:3692 [inline]
__do_sys_mount fs/namespace.c:3898 [inline]
__se_sys_mount+0x27f/0x2d0 fs/namespace.c:3875
__x64_sys_mount+0x67/0x80 fs/namespace.c:3875
do_syscall_64+0xd3/0x1d0
entry_SYSCALL_64_after_hwframe+0x72/0x7a

value changed: 0x0000000000000000 -> 0x0000000000000001

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 13875 Comm: syz-executor.4 Tainted: G W 6.9.0-rc2-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
==================================================================
EXT4-fs (sda1): re-mounted 5941fea2-f5fa-4b4e-b5ef-9af118b27b95 r/w. Quota mode: none.


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