On Wed, Mar 02, 2022 at 05:42:50PM -0500, J. Bruce Fields wrote: > On Wed, Mar 02, 2022 at 05:26:08PM -0500, Josef Bacik wrote: > > On Wed, Mar 02, 2022 at 05:04:50PM -0500, J. Bruce Fields wrote: > > > I started seeing generic/373 fail on recent linux-next in NFS testing. > > > > > > Bisect lands it on aaf40970b1d0 "fs: allow cross-vfsmount > > > reflink/dedupe". > > > > > > The test fails because a clone between two mounts is expected to fail, > > > and no longer does. > > > > > > In my setup both mounts are nfs mounts. They are mounts of different > > > exports, and the exports are exports of different filesystems. So it > > > does make sense that the clone should fail. > > > > > > I see the NFS client send a CLONE rpc to the server, and the server > > > return success. That seems wrong. > > > > > > Both exported filesystems are xfs, and from the code it looks like the > > > server calls vfs_clone_file_range(), which ends up calling > > > xfs_file_remap_range(). > > > > > > Are we missing a check now in that xfs case? > > > > > > I haven't looked any more closely at what's going on, so I could be > > > missing something. > > > > > > > Yeah there's a few fstests that test this functionality that need to be removed, > > I have patches pending for this in our fstests staging tree (since we run > > fstests nightly on our tree) > > > > https://github.com/btrfs/fstests/tree/staging > > > > Right now the patches just remove the tests from auto since that's what we run, > > I'll remove them properly once the patch lands in linus. Thanks, > > So, out of curiosity, what is xfs doing in this case? These are two > filesystems on separate partitions, is it falling back on a read/write > loop or something? I don't think so? I'm actually kind of confused, because nfsd does vfs_clone_file_range, and the only place I messed with for CLONE was ioctl_clone_file, so the patch changed literally nothing, unless you aren't using nfsd for the server? And if they are in fact two different file systems the i_sb != i_sb of the files, so there's something pretty strange going on here, my patch shouldn't affect your setup. Thanks, Josef