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BUG: KCSAN: data-race in block_uevent / inc_diskseq

write to 0xffff888101995220 of 8 bytes by task 3106 on cpu 0:
 inc_diskseq+0x2c/0x40 block/genhd.c:1457
 disk_force_media_change+0x9f/0xe0 block/disk-events.c:302
 __loop_clr_fd+0x248/0x3b0 drivers/block/loop.c:1174
 lo_release+0xe4/0xf0 drivers/block/loop.c:1743
 blkdev_put+0x3f2/0x470
 kill_block_super+0x47/0x60 fs/super.c:1649
 ext4_kill_sb+0x44/0x80 fs/ext4/super.c:7305
 deactivate_locked_super+0x73/0x1c0 fs/super.c:481
 deactivate_super+0x9b/0xb0 fs/super.c:514
 cleanup_mnt+0x272/0x2e0 fs/namespace.c:1254
 __cleanup_mnt+0x19/0x20 fs/namespace.c:1261
 task_work_run+0x135/0x1a0 kernel/task_work.c:180
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop+0xd6/0xe0 kernel/entry/common.c:171
 exit_to_user_mode_prepare+0x6c/0xb0 kernel/entry/common.c:204
 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline]
 syscall_exit_to_user_mode+0x26/0x140 kernel/entry/common.c:296
 do_syscall_64+0x4d/0xc0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

read to 0xffff888101995220 of 8 bytes by task 2777 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:1950 [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: 0x0000000000004003 -> 0x0000000000004008

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 2777 Comm: udevd Not tainted 6.6.0-rc3-syzkaller-00038-g0e945134b680 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/06/2023
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