For my testing I grabbed the master-next branch and rebased https://review.whamcloud.com/#/c/31790
In my initial testing using the default ZFS (0.7.5) that comes with Ubuntu I see the following error on startup.
[312807.501231] Lustre: DEBUG MARKER: /usr/src/lustre-2.11.51/lustre/tests/../utils/.libs/lctl get_param -n version 2>/dev/null || /usr/src/lustre-2.11.51/lustre/tests/../utils/.libs/lctl lustre_build_version 2>/dev/null || /usr/src/lustre-2.11.51/lustre/tests/../utils/.libs/lctl --version 2>
[312807.980495] osd_zfs: Unknown symbol dmu_objset_projectquota_enabled (err 0)
[312807.980574] osd_zfs: Unknown symbol dmu_assign_arcbuf_by_dbuf (err 0)
So looking at the zfs code ZFS_PROJINHERIT is defined but dmu_objset_projectquota_enabled() is missing. Also I can't seem to find where dmu_assign_archbuf_by_dbuf is being used.
James Simmons (uja.ornl@yahoo.com) uploaded a new patch: https://review.whamcloud.com/32304
Subject: LU-10997 build: add files to .gitignore
Project: fs/lustre-release
Branch: master
Current Patch Set: 1
Commit: 07056f71248838e678aba5ce8bae2bfcda941343
I see what went wrong. I had some newer ZFS sources in /usr/src which don't match what Ubuntu 18 ships with. So I moved it out of the way. Looking to see where the zfs source are I found them in /usr/src/linux-source-4.15.0/{spl/zfs}. So they are looked in the kernel source itself. We will have to update the source paths for the Ubuntu case.
Oleg Drokin (oleg.drokin@intel.com) merged in patch https://review.whamcloud.com/32304/
Subject: LU-10997 build: add files to .gitignore
Project: fs/lustre-release
Branch: master
Current Patch Set:
Commit: 734d944d98f4cbcaeebc462e979624e8bdfb7711
Their is something really wrong with the test setup with Ubuntu. Anything I push fails with:
Trying to load: pxelinux.cfg/1545a47a-0617-0b4b-bafe-af4b2b9c27ce[1S Trying to load: pxelinux.cfg/01-52-54-00-70-0d-c7[1S Booting from local disk...[1S Could not boot image: Error 0x7f8d81ff (http://ipxe.org/7f8d81ff)
I noticed the ARM64 is constantly crashing in the recent testing. Its the same reason as Ubuntu18 is now broken :
/usr/src/lustre-2.11.56/lustre/osd-ldiskfs/osd_io.c: In function ‘osd_bio_integrity_compare’:
/usr/src/lustre-2.11.56/lustre/osd-ldiskfs/osd_io.c:345:53: error: ‘struct bio’ has no member named ‘bi_bdev’; did you mean ‘bi_iter’?
struct blk_integrity bi = bdev_get_integrity(bio->*bi_bdev);
^~~~~~~
bi_iter
scripts/Makefile.build:332: recipe for target '/usr/src/lustre-2.11.56/lustre/osd-ldiskfs/osd_io.o' failed
make[6]: *** [/usr/src/lustre-2.11.56/lustre/osd-ldiskfs/osd_io.o] Error 1
Minh Sebastien found the staging module usage error but now we see the following when building:
checking whether to use Compat RDMA... /usr/bin/ofed_info*10:40:52* xargs: rpm: No such file or directory*10:40:52* configure: error: 10:40:52 You seem to have an OFED installed but have not installed it's devel package.10:40:52 If you still want to build Lustre for your OFED I/B stack, you need to install its devel headers RPM.10:40:52 Instead, if you want to build Lustre for your kernel's built-in I/B stack rather than your installed OFED stack, either remove the OFED package(s) or use -with-o2ib=no.10:40:52 10:40:52 dh_testdir*10:40:52* /usr/bin/make -C . -j 4*10:40:52* make[2]: Entering directory '/var/lib/jenkins/workspace/lustre
Resolved all the major Ubuntu issues!! Just took many patches 
Last patch https://review.whamcloud.com/#/c/33492 for complete Ubuntu18 client support 
Now that we are moving to Ubuntu 20 LTS we can close this and move the remaining tickets to that work to resolve.