loop: fix zero sized loop for block special file
By default, /dev/sda is block specail file from devtmpfs, getattr will
return file size as zero, causing loop failed for raw block device.
We can add bdev_statx() to return device size, however this may introduce
changes that are not acknowledged by user. Fix this problem by reverting
changes for block special file, file mapping host is set to bdev inode
while opening, and use i_size_read() directly to get device size.
Fixes: 47b71abd5846 ("loop: use vfs_getattr_nosec for accurate file size")
Reported-by: kernel test robot <oliver.sang@intel.com>
Closes: https://lore.kernel.org/oe-lkp/202508200409.b2459c02-lkp@intel.com
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
1 file changed
