==================================================================
BUG: KCSAN: data-race in blkdev_read_iter / set_capacity_and_notify

write to 0xffff888101b860c8 of 8 bytes by task 13577 on cpu 0:
 set_capacity block/genhd.c:63 [inline]
 set_capacity_and_notify+0xab/0x1d0 block/genhd.c:77
 loop_set_size drivers/block/loop.c:232 [inline]
 loop_configure+0xd53/0xf50 drivers/block/loop.c:1060
 lo_ioctl+0x633/0x1260
 blkdev_ioctl+0x20e/0x440 block/ioctl.c:588
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:874 [inline]
 __se_sys_ioctl+0xcb/0x140 fs/ioctl.c:860
 __x64_sys_ioctl+0x3f/0x50 fs/ioctl.c:860
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff888101b860c8 of 8 bytes by task 1806 on cpu 1:
 bdev_nr_sectors include/linux/genhd.h:205 [inline]
 bdev_nr_bytes include/linux/genhd.h:210 [inline]
 blkdev_read_iter+0x40/0x380 block/fops.c:570
 call_read_iter include/linux/fs.h:2068 [inline]
 new_sync_read fs/read_write.c:400 [inline]
 vfs_read+0x66c/0x750 fs/read_write.c:481
 ksys_read+0xd9/0x190 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+0x3e/0x50 fs/read_write.c:627
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x0000000000000000 -> 0x000000000000007c

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 1806 Comm: udevd Not tainted 5.17.0-rc5-syzkaller-00189-g53ab78cd6d5a-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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I/O error, dev loop4, sector 0 op 0x0:(READ) flags 0x80700 phys_seg 1 prio class 0
I/O error, dev loop4, sector 0 op 0x0:(READ) flags 0x80700 phys_seg 1 prio class 0
blk_print_req_error: 10 callbacks suppressed
I/O error, dev loop4, sector 0 op 0x0:(READ) flags 0x80700 phys_seg 1 prio class 0
I/O error, dev loop4, sector 0 op 0x0:(READ) flags 0x80700 phys_seg 1 prio class 0
I/O error, dev loop4, sector 0 op 0x0:(READ) flags 0x0 phys_seg 1 prio class 0
Buffer I/O error on dev loop4, logical block 0, async page read
I/O error, dev loop4, sector 8064 op 0x0:(READ) flags 0x80700 phys_seg 1 prio class 0
I/O error, dev loop4, sector 24 op 0x0:(READ) flags 0x80700 phys_seg 1 prio class 0
I/O error, dev loop4, sector 24 op 0x0:(READ) flags 0x0 phys_seg 1 prio class 0
Buffer I/O error on dev loop4, logical block 3, async page read
I/O error, dev loop4, sector 8064 op 0x0:(READ) flags 0x80700 phys_seg 1 prio class 0
I/O error, dev loop4, sector 0 op 0x0:(READ) flags 0x80700 phys_seg 1 prio class 0
I/O error, dev loop4, sector 8064 op 0x0:(READ) flags 0x80700 phys_seg 1 prio class 0
I/O error, dev loop3, sector 0 op 0x0:(READ) flags 0x80700 phys_seg 1 prio class 0
I/O error, dev loop3, sector 0 op 0x0:(READ) flags 0x80700 phys_seg 1 prio class 0