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I/O error, dev loop4, sector 0 op 0x0:(READ) flags 0x80700 phys_seg 1 prio class 2
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BUG: KCSAN: data-race in bdev_set_nr_sectors / blkdev_read_iter

write to 0xffff888100630008 of 8 bytes by task 13834 on cpu 0:
 bdev_set_nr_sectors+0x50/0x70 block/bdev.c:428
 set_capacity block/genhd.c:61 [inline]
 set_capacity_and_notify+0x6e/0x170 block/genhd.c:74
 loop_set_size+0x2e/0x70 drivers/block/loop.c:237
 loop_configure+0xaf9/0xca0 drivers/block/loop.c:1098
 lo_ioctl+0x682/0x12e0
 blkdev_ioctl+0x375/0x460 block/ioctl.c:633
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:871 [inline]
 __se_sys_ioctl+0xcf/0x140 fs/ioctl.c:857
 __x64_sys_ioctl+0x43/0x50 fs/ioctl.c:857
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0x44/0x110 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

read to 0xffff888100630008 of 8 bytes by task 3478 on cpu 1:
 bdev_nr_sectors include/linux/blkdev.h:769 [inline]
 bdev_nr_bytes include/linux/blkdev.h:774 [inline]
 blkdev_read_iter+0x58/0x2c0 block/fops.c:708
 call_read_iter include/linux/fs.h:2078 [inline]
 new_sync_read fs/read_write.c:395 [inline]
 vfs_read+0x34c/0x480 fs/read_write.c:476
 ksys_read+0xeb/0x1a0 fs/read_write.c:619
 __do_sys_read fs/read_write.c:629 [inline]
 __se_sys_read fs/read_write.c:627 [inline]
 __x64_sys_read+0x42/0x50 fs/read_write.c:627
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0x44/0x110 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

value changed: 0x0000000000000000 -> 0x00000000000000a4

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 3478 Comm: udevd Not tainted 6.7.0-syzkaller-00119-g5db8752c3b81 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023
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