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BUG: KCSAN: data-race in block_uevent / inc_diskseq

write to 0xffff888102208a20 of 8 bytes by task 3452 on cpu 0:
 inc_diskseq+0x2c/0x40 block/genhd.c:1514
 disk_force_media_change+0x9f/0xf0 block/disk-events.c:297
 loop_configure+0x679/0xa50 drivers/block/loop.c:1087
 lo_ioctl+0x613/0x14f0
 blkdev_ioctl+0x359/0x450 block/ioctl.c:693
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:906 [inline]
 __se_sys_ioctl+0xc9/0x140 fs/ioctl.c:892
 __x64_sys_ioctl+0x43/0x50 fs/ioctl.c:892
 x64_sys_call+0x1690/0x2dc0 arch/x86/include/generated/asm/syscalls_64.h:17
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff888102208a20 of 8 bytes by task 3001 on cpu 1:
 block_uevent+0x31/0x50 block/genhd.c:1253
 dev_uevent+0x2f3/0x380 drivers/base/core.c:2673
 kobject_uevent_env+0x33d/0x550 lib/kobject_uevent.c:573
 kobject_synth_uevent+0x6a5/0x7d0 lib/kobject_uevent.c:207
 uevent_store+0x24/0x60 drivers/base/core.c:2749
 dev_attr_store+0x47/0x70 drivers/base/core.c:2439
 sysfs_kf_write+0xae/0xd0 fs/sysfs/file.c:139
 kernfs_fop_write_iter+0x1c8/0x2c0 fs/kernfs/file.c:334
 new_sync_write fs/read_write.c:586 [inline]
 vfs_write+0x77b/0x920 fs/read_write.c:679
 ksys_write+0xe8/0x1b0 fs/read_write.c:731
 __do_sys_write fs/read_write.c:742 [inline]
 __se_sys_write fs/read_write.c:739 [inline]
 __x64_sys_write+0x42/0x50 fs/read_write.c:739
 x64_sys_call+0x287e/0x2dc0 arch/x86/include/generated/asm/syscalls_64.h:2
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x0000000000000004 -> 0x0000000000000026

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 3001 Comm: udevd Not tainted 6.14.0-rc4-syzkaller-00278-gece144f151ac #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
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