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BUG: KCSAN: data-race in loop_configure / loop_queue_rq

write to 0xffff888101dbda78 of 4 bytes by task 7742 on cpu 1:
 loop_configure+0xb28/0xc30 drivers/block/loop.c:1100
 lo_ioctl+0x641/0x1290
 blkdev_ioctl+0x20e/0x440 block/ioctl.c:614
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:870 [inline]
 __se_sys_ioctl+0xcb/0x140 fs/ioctl.c:856
 __x64_sys_ioctl+0x3f/0x50 fs/ioctl.c:856
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

read to 0xffff888101dbda78 of 4 bytes by task 2297 on cpu 0:
 loop_queue_rq+0x4b/0x650 drivers/block/loop.c:1806
 __blk_mq_issue_directly+0x66/0x410 block/blk-mq.c:2459
 __blk_mq_try_issue_directly+0x25d/0x2c0 block/blk-mq.c:2512
 blk_mq_try_issue_directly block/blk-mq.c:2536 [inline]
 blk_mq_submit_bio+0xb17/0xe90 block/blk-mq.c:2862
 __submit_bio block/blk-core.c:595 [inline]
 __submit_bio_noacct_mq block/blk-core.c:672 [inline]
 submit_bio_noacct_nocheck+0x83d/0xaa0 block/blk-core.c:689
 submit_bio_noacct+0x696/0x800 block/blk-core.c:796
 submit_bio+0xfb/0x110
 submit_bh_wbc+0x2b0/0x2f0 fs/buffer.c:2719
 submit_bh fs/buffer.c:2725 [inline]
 block_read_full_folio+0x4a4/0x520 fs/buffer.c:2340
 blkdev_read_folio+0x18/0x20 block/fops.c:381
 filemap_read_folio mm/filemap.c:2394 [inline]
 do_read_cache_folio+0x191/0x3f0 mm/filemap.c:3519
 read_cache_folio+0x36/0x40 mm/filemap.c:3551
 read_mapping_folio include/linux/pagemap.h:762 [inline]
 read_part_sector+0x76/0x1e0 block/partitions/core.c:714
 msdos_partition+0xa5/0x1b80 block/partitions/msdos.c:592
 check_partition block/partitions/core.c:146 [inline]
 blk_add_partitions block/partitions/core.c:599 [inline]
 bdev_disk_changed+0x40d/0xc30 block/partitions/core.c:685
 blkdev_get_whole+0x256/0x270 block/bdev.c:684
 blkdev_get_by_dev+0x248/0x650 block/bdev.c:821
 blkdev_open+0xac/0x140 block/fops.c:485
 do_dentry_open+0x51a/0x8b0 fs/open.c:878
 vfs_open+0x43/0x50 fs/open.c:1014
 do_open fs/namei.c:3557 [inline]
 path_openat+0x169d/0x1b00 fs/namei.c:3691
 do_filp_open+0x105/0x220 fs/namei.c:3718
 do_sys_openat2+0xb5/0x2a0 fs/open.c:1311
 do_sys_open fs/open.c:1327 [inline]
 __do_sys_openat fs/open.c:1343 [inline]
 __se_sys_openat fs/open.c:1338 [inline]
 __x64_sys_openat+0xef/0x110 fs/open.c:1338
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0x00000000 -> 0x00000001

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 2297 Comm: udevd Not tainted 5.19.0-syzkaller-13930-g7ebfc85e2cd7-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022
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 loop2: unable to read partition table