================================================================== BUG: KCSAN: data-race in block_uevent / inc_diskseq write to 0xffff888101eafe20 of 8 bytes by task 7737 on cpu 0: inc_diskseq+0x2c/0x40 block/genhd.c:1517 disk_force_media_change+0xa7/0xf0 block/disk-events.c:297 __loop_clr_fd drivers/block/loop.c:1192 [inline] lo_release+0x2d2/0x400 drivers/block/loop.c:1772 bdev_release+0x3c6/0x420 block/bdev.c:-1 blkdev_release+0x15/0x20 block/fops.c:660 __fput+0x2ac/0x640 fs/file_table.c:465 fput_close_sync+0xc0/0x110 fs/file_table.c:570 __do_sys_close fs/open.c:1581 [inline] __se_sys_close fs/open.c:1566 [inline] __x64_sys_close+0x55/0xe0 fs/open.c:1566 x64_sys_call+0x262b/0x2e10 arch/x86/include/generated/asm/syscalls_64.h:4 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xc9/0x1c0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f read to 0xffff888101eafe20 of 8 bytes by task 3008 on cpu 1: block_uevent+0x31/0x50 block/genhd.c:1256 dev_uevent+0x304/0x390 drivers/base/core.c:2674 uevent_show+0x11e/0x210 drivers/base/core.c:2732 dev_attr_show+0x3a/0xa0 drivers/base/core.c:2424 sysfs_kf_seq_show+0x1a8/0x280 fs/sysfs/file.c:65 kernfs_seq_show+0x7c/0x90 fs/kernfs/file.c:205 seq_read_iter+0x2c8/0x970 fs/seq_file.c:230 kernfs_fop_read_iter+0xc3/0x320 fs/kernfs/file.c:279 new_sync_read fs/read_write.c:489 [inline] vfs_read+0x5e6/0x710 fs/read_write.c:570 ksys_read+0xeb/0x1b0 fs/read_write.c:713 __do_sys_read fs/read_write.c:722 [inline] __se_sys_read fs/read_write.c:720 [inline] __x64_sys_read+0x42/0x50 fs/read_write.c:720 x64_sys_call+0x2a3b/0x2e10 arch/x86/include/generated/asm/syscalls_64.h:1 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xc9/0x1c0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f value changed: 0x0000000000000623 -> 0x0000000000000624 Reported by Kernel Concurrency Sanitizer on: CPU: 1 UID: 0 PID: 3008 Comm: udevd Not tainted 6.14.0-syzkaller-13389-ga52a3c18cdf3 #0 PREEMPT(voluntary) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 ==================================================================