On 6/7/2024 10:42 PM, Christoph Hellwig wrote: > On Fri, Jun 07, 2024 at 11:15:55AM +0200, Cyril Hrubis wrote: >> If fallcate is implemented but zero and discard operations are not >> supported by the filesystem the backing file is on we continue to fill >> dmesg with errors from the blk_mq_end_request() since each time we call >> fallocate() on the loop device the EOPNOTSUPP error from lo_fallocate() >> ends up propagated into the block layer. In the end syscall succeeds >> since the blkdev_issue_zeroout() falls back to writing zeroes which >> makes the errors even more misleading and confusing. >> >> How to reproduce: >> >> 1. make sure /tmp is mounted as tmpfs >> 2. dd if=/dev/zero of=/tmp/disk.img bs=1M count=100 >> 3. losetup /dev/loop0 /tmp/disk.img >> 4. mkfs.ext2 /dev/loop0 >> 5. dmesg |tail > Can you wire this up for blktests? Please CC Shin'ichiro Kawasaki <shinichiro.kawasaki@xxxxxxx> and me when you do that .. -ck
