[moderation] [block?] KCSAN: data-race in bdev_statx / queue_limits_commit_update (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 05df91921da6 Merge tag 'v6.16-rc4-smb3-client-fixes' of gi..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=145e0bd4580000
kernel config: https://syzkaller.appspot.com/x/.config?x=eea96b85b0259840
dashboard link: https://syzkaller.appspot.com/bug?extid=b3987a634290a5f1bd78
compiler: Debian clang version 20.1.7 (++20250616065708+6146a88f6049-1~exp1~20250616065826.132), Debian LLD 20.1.7
CC: [ax...@kernel.dk linux...@vger.kernel.org linux-...@vger.kernel.org]

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/14cf6bc00f11/disk-05df9192.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/255efbd4a0b9/vmlinux-05df9192.xz
kernel image: https://storage.googleapis.com/syzbot-assets/3b3ca67d595e/bzImage-05df9192.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+b3987a...@syzkaller.appspotmail.com

==================================================================
BUG: KCSAN: data-race in bdev_statx / queue_limits_commit_update

read to 0xffff8881009fc0b8 of 4 bytes by task 3594 on cpu 0:
queue_io_min include/linux/blkdev.h:1327 [inline]
bdev_io_min include/linux/blkdev.h:1332 [inline]
bdev_statx+0x295/0x2d0 block/bdev.c:1342
vfs_getattr_nosec+0x1b6/0x1e0 fs/stat.c:227
vfs_getattr fs/stat.c:262 [inline]
vfs_fstat fs/stat.c:281 [inline]
__do_sys_newfstat fs/stat.c:555 [inline]
__se_sys_newfstat+0x96/0x2e0 fs/stat.c:550
__x64_sys_newfstat+0x31/0x40 fs/stat.c:550
x64_sys_call+0x27e1/0x2fb0 arch/x86/include/generated/asm/syscalls_64.h:6
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xd2/0x200 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f

write to 0xffff8881009fc078 of 184 bytes by task 22343 on cpu 1:
queue_limits_commit_update+0x4c/0x110 block/blk-settings.c:456
loop_configure+0x79c/0xa50 drivers/block/loop.c:1053
lo_ioctl+0x559/0x15d0 drivers/block/loop.c:-1
blkdev_ioctl+0x34f/0x440 block/ioctl.c:704
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:907 [inline]
__se_sys_ioctl+0xce/0x140 fs/ioctl.c:893
__x64_sys_ioctl+0x43/0x50 fs/ioctl.c:893
x64_sys_call+0x19a8/0x2fb0 arch/x86/include/generated/asm/syscalls_64.h:17
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xd2/0x200 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 22343 Comm: syz.0.4900 Not tainted 6.16.0-rc4-syzkaller-00319-g05df91921da6 #0 PREEMPT(voluntary)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
==================================================================
loop0: detected capacity change from 0 to 512
EXT4-fs (loop0): encrypted files will use data=ordered instead of data journaling mode
workqueue: Failed to create a rescuer kthread for wq "ext4-rsv-conversion": -EINTR
EXT4-fs: failed to create workqueue
EXT4-fs (loop0): mount failed


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