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BUG: KCSAN: data-race in block_uevent / inc_diskseq

write to 0xffff888100e2ca20 of 8 bytes by task 3089 on cpu 1:
 inc_diskseq+0x2c/0x40 block/genhd.c:1467
 disk_force_media_change+0x9f/0xe0 block/disk-events.c:297
 __loop_clr_fd+0x242/0x3a0 drivers/block/loop.c:1170
 loop_clr_fd drivers/block/loop.c:1253 [inline]
 lo_ioctl+0xe93/0x12e0 drivers/block/loop.c:1557
 blkdev_ioctl+0x375/0x460 block/ioctl.c:634
 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+0xcd/0x1d0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

read to 0xffff888100e2ca20 of 8 bytes by task 8793 on cpu 0:
 block_uevent+0x31/0x50 block/genhd.c:1201
 dev_uevent+0x2e9/0x360 drivers/base/core.c:2591
 uevent_show+0x102/0x1e0 drivers/base/core.c:2647
 dev_attr_show+0x39/0x90 drivers/base/core.c:2350
 sysfs_kf_seq_show+0x179/0x250 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:2079 [inline]
 new_sync_read fs/read_write.c:395 [inline]
 vfs_read+0x5ab/0x6a0 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+0xcd/0x1d0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

value changed: 0x0000000000000d88 -> 0x0000000000000d8b

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 8793 Comm: udevd Not tainted 6.8.0-rc2-syzkaller-00397-g56897d51886f #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024
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