[moderation] [ext4?] KCSAN: data-race in has_bh_in_lru / invalidate_bh_lrus_cpu (8)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 3b47bc037bd4 Merge tag 'pinctrl-v6.7-2' of git://git.kerne..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=13c39eb4e80000
kernel config: https://syzkaller.appspot.com/x/.config?x=585869067cd7ce59
dashboard link: https://syzkaller.appspot.com/bug?extid=3d34f041a9dc781b81cf
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
CC: [adilger...@dilger.ca linux...@vger.kernel.org linux-...@vger.kernel.org linux-...@vger.kernel.org ty...@mit.edu]

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/231e21487056/disk-3b47bc03.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/eae871bb6b73/vmlinux-3b47bc03.xz
kernel image: https://storage.googleapis.com/syzbot-assets/0c20f8f08d47/bzImage-3b47bc03.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+3d34f0...@syzkaller.appspotmail.com

EXT4-fs: Ignoring removed bh option
==================================================================
BUG: KCSAN: data-race in has_bh_in_lru / invalidate_bh_lrus_cpu

write to 0xffff888237c2a448 of 8 bytes by task 28864 on cpu 0:
__invalidate_bh_lrus fs/buffer.c:1488 [inline]
invalidate_bh_lrus_cpu+0x82/0xb0 fs/buffer.c:1533
lru_add_and_bh_lrus_drain mm/swap.c:768 [inline]
lru_add_drain_per_cpu+0x70/0x90 mm/swap.c:787
process_one_work kernel/workqueue.c:2630 [inline]
process_scheduled_works+0x5b8/0xa30 kernel/workqueue.c:2703
worker_thread+0x525/0x730 kernel/workqueue.c:2784
kthread+0x1d7/0x210 kernel/kthread.c:388
ret_from_fork+0x48/0x60 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242

read to 0xffff888237c2a448 of 8 bytes by task 18477 on cpu 1:
has_bh_in_lru+0x35/0x1e0 fs/buffer.c:1510
smp_call_function_many_cond+0x2e4/0xc20 kernel/smp.c:808
on_each_cpu_cond_mask+0x3c/0x80 kernel/smp.c:1023
on_each_cpu_cond include/linux/smp.h:105 [inline]
invalidate_bh_lrus+0x2a/0x30 fs/buffer.c:1519
kill_bdev block/bdev.c:75 [inline]
set_blocksize+0x260/0x290 block/bdev.c:152
sb_set_blocksize+0x2d/0xb0 block/bdev.c:161
ext4_load_super fs/ext4/super.c:5108 [inline]
__ext4_fill_super fs/ext4/super.c:5236 [inline]
ext4_fill_super+0xad5/0x39a0 fs/ext4/super.c:5712
get_tree_bdev+0x272/0x300 fs/super.c:1598
ext4_get_tree+0x1c/0x20 fs/ext4/super.c:5744
vfs_get_tree+0x51/0x1b0 fs/super.c:1771
do_new_mount+0x203/0x660 fs/namespace.c:3337
path_mount+0x496/0xb30 fs/namespace.c:3664
do_mount fs/namespace.c:3677 [inline]
__do_sys_mount fs/namespace.c:3886 [inline]
__se_sys_mount+0x27f/0x2d0 fs/namespace.c:3863
__x64_sys_mount+0x67/0x80 fs/namespace.c:3863
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x44/0x110 arch/x86/entry/common.c:82
entry_SYSCALL_64_after_hwframe+0x63/0x6b

value changed: 0xffff88814bf03dd0 -> 0x0000000000000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 18477 Comm: syz-executor.1 Not tainted 6.7.0-rc3-syzkaller-00033-g3b47bc037bd4 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023
==================================================================
EXT4-fs (loop1): can't mount with data=, fs mounted w/o journal


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.