KCSAN: data-race in __loop_clr_fd / blkdev_get_no

Kernel	Title	Repro	Cause bisect	Fix bisect	Count	Last	Reported	Patched	Status
upstream	KCSAN: data-race in __loop_clr_fd / blkdev_get_no_open (2) block				2	1059d	1088d	0/26	auto-closed as invalid on 2021/07/06 19:26

================================================================== BUG: KCSAN: data-race in __loop_clr_fd / blkdev_get_no_open write to 0xffff888102585160 of 4 bytes by task 1990 on cpu 1: __loop_clr_fd+0x5a1/0x630 drivers/block/loop.c:1293 loop_clr_fd drivers/block/loop.c:1336 [inline] lo_ioctl+0x9eb/0x11f0 drivers/block/loop.c:1694 blkdev_ioctl+0x1d0/0x3c0 block/ioctl.c:583 block_ioctl+0x6d/0x80 fs/block_dev.c:1667 vfs_ioctl fs/ioctl.c:48 [inline] __do_sys_ioctl fs/ioctl.c:753 [inline] __se_sys_ioctl+0xcb/0x140 fs/ioctl.c:739 __x64_sys_ioctl+0x3f/0x50 fs/ioctl.c:739 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xae read to 0xffff888102585160 of 4 bytes by task 4845 on cpu 0: blkdev_get_no_open+0xe1/0x180 fs/block_dev.c:1379 blkdev_get_by_dev+0xb7/0x4a0 fs/block_dev.c:1440 blkdev_reread_part block/ioctl.c:100 [inline] blkdev_common_ioctl+0xd25/0x10a0 block/ioctl.c:508 blkdev_ioctl+0x16e/0x3c0 block/ioctl.c:577 block_ioctl+0x6d/0x80 fs/block_dev.c:1667 vfs_ioctl fs/ioctl.c:48 [inline] __do_sys_ioctl fs/ioctl.c:753 [inline] __se_sys_ioctl+0xcb/0x140 fs/ioctl.c:739 __x64_sys_ioctl+0x3f/0x50 fs/ioctl.c:739 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xae Reported by Kernel Concurrency Sanitizer on: CPU: 0 PID: 4845 Comm: systemd-udevd Not tainted 5.12.0-rc3-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ==================================================================