ABI files may need a bump

[jonathonf]

System information

Type	Version/Name
Distribution Name	Ubuntu
Distribution Version	21.04
Kernel Version	5.13.1
Architecture	amd64
OpenZFS Version	2.1.0

Describe the problem you're observing

Attempting to build ZFS 2.1.0 with Debian packaging tools will fail at the make checkabi step. Possibly the .abi files need to be updated?

Describe how to reproduce the problem

./autogen.sh
./configure
make checkabi

Include any warning/errors/backtraces from the system logs

Example output:

# Upstream provides an ABI guarantee that we validate here                                                                                                 
/usr/bin/make checkabi
...
make[4]: Entering directory '/localnet/src/zfs/2.1/zfs-linux-2.1.0/lib/libzfs'
for lib in libzfs.la ; do \
abidiff --no-unreferenced-symbols \
   --headers-dir1 ../../include \
   --suppressions ${lib%.la}.suppr \
   ${lib%.la}.abi .libs/${lib%.la}.so ; \
done
Functions changes summary: 0 Removed, 74 Changed (250 filtered out), 0 Added functions
Variables changes summary: 0 Removed, 0 Changed (17 filtered out), 0 Added variables

74 functions with some indirect sub-type change:

  [C] 'function prop_changelist_t* changelist_gather(zfs_handle_t*, zfs_prop_t, int, int)' at libzfs_changelist.c:624:1 has some indirect sub-type changes:
    parameter 1 of type 'zfs_handle_t*' has sub-type changes:
      in pointed to type 'typedef zfs_handle_t' at libzfs.h:195:1:
        underlying type 'struct zfs_handle' at libzfs_impl.h:77:1 changed:
          type size hasn't changed
          1 data member changes (5 filtered):
            type of 'libzfs_handle_t* zfs_handle::zfs_hdl' changed:
              in pointed to type 'typedef libzfs_handle_t' at libzfs.h:197:1:
                underlying type 'struct libzfs_handle' at libzfs_impl.h:48:1 changed:
                  type size hasn't changed
                  no data member changes (4 filtered);

  [C] 'function int find_shares_object(differ_info_t*)' at libzfs_util_os.c:304:1 has some indirect sub-type changes:
    parameter 1 of type 'differ_info_t*' has sub-type changes:
      in pointed to type 'typedef differ_info_t' at libzfs_impl.h:240:1:
        underlying type 'struct differ_info' at libzfs_impl.h:221:1 changed:
          type size hasn't changed
          no data member changes (5 filtered);

...

Many more lines, snipped for brevity (I can upload fuller logs as needed).

[l1k]

This only happens with abigail version 1.8 or newer. Version 1.7 is fine.

Thus, you'll only see this on Debian bullseye or Ubuntu 21.04, but not on Debian buster or Ubuntu 20.04.

I've just bisected the issue to commit 8a0825e319c3. Either we need to update the abi files or we need to bail out of "make checkabi" if abigail 1.8 is installed. Probably the latter because this looks like a bug. I'll get in touch with the libabigail devs.

Bugzilla #28289

[gmelikov]

Hm, I've recently tested and got only 3 changes found.

I'll plan to use 1.8+ in our CI and add version check in make files, because of #12459

[behlendorf]

@gmelikov thanks, that sounds like the best way to address this.

[gmelikov]

Closed in #12529