Comment 15 for bug 1907262

Performing verification for Bionic.

I spun up a m5d.4xlarge instance on AWS, to utilise the 2x 300GB NVMe drives that support block discard.

I enabled -proposed, and installed the 4.15.0-128-generic kernel.

The following is the repro session running through the full testcase:

https://paste.ubuntu.com/p/VpwjbRRcy6/

A 2 disk Raid10 array was created, LVM created and formatted ext4. I let the consistency checks finish, and created, then deleted a file. Did another consistency check, then performed a fstrim. After another consistency check, we unmount and perform a fsck on each individual disk.

root@ip-172-31-10-77:~# fsck.ext4 -n -f /dev/VolGroup/root
e2fsck 1.44.1 (24-Mar-2018)
Pass 1: Checking inodes, blocks, and sizes
Pass 2: Checking directory structure
Pass 3: Checking directory connectivity
Pass 4: Checking reference counts
Pass 5: Checking group summary information
/dev/VolGroup/root: 11/6553600 files (0.0% non-contiguous), 557848/26214400 blocks

root@ip-172-31-10-77:~# fsck.ext4 -n -f /dev/VolGroup/root
e2fsck 1.44.1 (24-Mar-2018)
Pass 1: Checking inodes, blocks, and sizes
Pass 2: Checking directory structure
Pass 3: Checking directory connectivity
Pass 4: Checking reference counts
Pass 5: Checking group summary information
/dev/VolGroup/root: 11/6553600 files (0.0% non-contiguous), 557848/26214400 blocks

Both of them pass, there is no corruption to the filesystem.

4.15.0-128-generic fixes the problem, the revert is effective.

Marking bug as verified for Bionic.