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BUG: KCSAN: data-race in block_uevent / inc_diskseq

write to 0xffff8881011d1620 of 8 bytes by task 26839 on cpu 0:
 inc_diskseq+0x2c/0x40 block/genhd.c:1457
 disk_force_media_change+0x9f/0xe0 block/disk-events.c:302
 loop_configure+0x70d/0xca0 drivers/block/loop.c:1070
 lo_ioctl+0x682/0x12e0
 blkdev_ioctl+0x375/0x460 block/ioctl.c:630
 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:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

read to 0xffff8881011d1620 of 8 bytes by task 3394 on cpu 1:
 block_uevent+0x31/0x50 block/genhd.c:1191
 dev_uevent+0x2e9/0x360 drivers/base/core.c:2590
 uevent_show+0x102/0x1e0 drivers/base/core.c:2646
 dev_attr_show+0x39/0x90 drivers/base/core.c:2349
 sysfs_kf_seq_show+0x179/0x240 fs/sysfs/file.c:59
 kernfs_seq_show+0x78/0x90 fs/kernfs/file.c:205
 seq_read_iter+0x2bc/0x8f0 fs/seq_file.c:230
 kernfs_fop_read_iter+0xc8/0x2e0 fs/kernfs/file.c:279
 call_read_iter include/linux/fs.h:1979 [inline]
 new_sync_read fs/read_write.c:389 [inline]
 vfs_read+0x3da/0x5c0 fs/read_write.c:470
 ksys_read+0xeb/0x1a0 fs/read_write.c:613
 __do_sys_read fs/read_write.c:623 [inline]
 __se_sys_read fs/read_write.c:621 [inline]
 __x64_sys_read+0x42/0x50 fs/read_write.c:621
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0x0000000000002355 -> 0x0000000000002356

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 3394 Comm: udevd Not tainted 6.6.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/04/2023
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I/O error, dev loop2, sector 0 op 0x0:(READ) flags 0x80700 phys_seg 1 prio class 2