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BUG: KCSAN: data-race in lo_ioctl / lo_ioctl

read-write to 0xffff888101fc0764 of 1 bytes by task 19965 on cpu 1:
 dev_set_uevent_suppress include/linux/device.h:783 [inline]
 loop_change_fd drivers/block/loop.c:578 [inline]
 lo_ioctl+0x243/0x12e0 drivers/block/loop.c:1561
 blkdev_ioctl+0x38e/0x480 block/ioctl.c:615
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:870 [inline]
 __se_sys_ioctl+0xc9/0x140 fs/ioctl.c:856
 __x64_sys_ioctl+0x43/0x50 fs/ioctl.c:856
 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

read-write to 0xffff888101fc0764 of 1 bytes by task 19964 on cpu 0:
 dev_set_uevent_suppress include/linux/device.h:783 [inline]
 loop_change_fd drivers/block/loop.c:638 [inline]
 lo_ioctl+0x1254/0x12e0 drivers/block/loop.c:1561
 blkdev_ioctl+0x38e/0x480 block/ioctl.c:615
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:870 [inline]
 __se_sys_ioctl+0xc9/0x140 fs/ioctl.c:856
 __x64_sys_ioctl+0x43/0x50 fs/ioctl.c:856
 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: 0x17 -> 0x07

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 19964 Comm: syz-executor.5 Not tainted 6.4.0-rc6-syzkaller-00037-gb6dad5178cea #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/27/2023
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