==================================================================
BUG: KCSAN: data-race in block_uevent / inc_diskseq

write to 0xffff888102416a18 of 8 bytes by task 4822 on cpu 1:
 inc_diskseq+0x2d/0x40 block/genhd.c:1577
 disk_force_media_change+0x9e/0xe0 block/disk-events.c:297
 __loop_clr_fd drivers/block/loop.c:1136 [inline]
 lo_release+0x2cb/0x400 drivers/block/loop.c:1716
 bdev_release+0x373/0x3d0 block/bdev.c:-1
 blkdev_release+0x15/0x20 block/fops.c:684
 __fput+0x29b/0x650 fs/file_table.c:465
 fput_close_sync+0x6e/0x120 fs/file_table.c:570
 __do_sys_close fs/open.c:1589 [inline]
 __se_sys_close fs/open.c:1574 [inline]
 __x64_sys_close+0x56/0xf0 fs/open.c:1574
 x64_sys_call+0x2747/0x2fb0 arch/x86/include/generated/asm/syscalls_64.h:4
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd2/0x200 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff888102416a18 of 8 bytes by task 3007 on cpu 0:
 block_uevent+0x31/0x50 block/genhd.c:1315
 dev_uevent+0x34c/0x3d0 drivers/base/core.c:2703
 uevent_show+0x11a/0x200 drivers/base/core.c:2759
 dev_attr_show+0x3f/0xa0 drivers/base/core.c:2424
 sysfs_kf_seq_show+0x1a0/0x280 fs/sysfs/file.c:65
 kernfs_seq_show+0x82/0xa0 fs/kernfs/file.c:205
 seq_read_iter+0x316/0x940 fs/seq_file.c:230
 kernfs_fop_read_iter+0xc4/0x300 fs/kernfs/file.c:279
 new_sync_read fs/read_write.c:491 [inline]
 vfs_read+0x5ca/0x6f0 fs/read_write.c:572
 ksys_read+0xda/0x1a0 fs/read_write.c:715
 __do_sys_read fs/read_write.c:724 [inline]
 __se_sys_read fs/read_write.c:722 [inline]
 __x64_sys_read+0x40/0x50 fs/read_write.c:722
 x64_sys_call+0x2d77/0x2fb0 arch/x86/include/generated/asm/syscalls_64.h:1
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd2/0x200 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x00000000000000b7 -> 0x00000000000000b8

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 3007 Comm: udevd Not tainted 6.15.0-syzkaller-12426-ge271ed52b344 #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
==================================================================