Hi, We switched to using BLKZEROOUT ioctl in libcryptsetup, and now we see a lot of messages like : operation not supported error, dev loop1, sector 0 op 0x9:(WRITE_ZEROES) flags 0x8000800 phys_seg 0 prio class 0 But the operation succeeds (ioctl returns 0). As it seems, this happens when a loop device is allocated over a file on NFS mounted directory. Easy to reproduce (5.19-rc8) by doing this in NFS mounted dir: # truncate -s 1M test.img # losetup /dev/loop1 test.img # fallocate -zn -l 1048576 /dev/loop1 Shouldn't the block layer be quiet here and just switch to a different wipe method? (I think it happens in other cases.) It is perhaps just a benign message, but it can trigger some reports. Milan
