Description of problem:
The test case ./tests/bugs/glusterfs/bug-866459.t seems to be failing on s390x due to linux-aio being enabled on the case test.
If I comment out the line that enables linux-aio, the test case will pass.

This line fails as it seems that we are unable to write files to /mnt/glusterfs/0/ when the linux-aio feature is on.
dd of=$M0/a if=/dev/urandom bs=1024k count=1 2>&1 > /dev/null

Upon further investigation, I also noticed that when I try to touch a file on /mnt/glusterfs/0/, it works. But whenever I try to edit the file on vim, it will fail with "/mnt/glusterfs/0/a" E667: Fsync failed.

How important is it to have linux-aio enable in the test case? This behaviour regarding linux-aio being enabled has been seen before in previous bug reports but it seems to been fixed on x86.

Version-Release number of selected component (if applicable):
v5.3

How reproducible:
Always

Steps to Reproduce:
1. Build Glusterfs v5.3 from source
2. Run the test case with ./run-tests.sh
3. Or just enable gluster feature linux-aio and try to write files

Actual results:
Test fails and /mnt/glusterfs/0/a uneditable

Expected results:
Test passes and /mnt/glusterfs/0/a editable

Additional info: (I can upload full logs if needed)
Snippets of /var/log/glusterfs/mnt-glusterfs-0.log
[2019-02-25 15:08:41.017171] W [MSGID: 114031] [client-rpc-fops_v2.c:680:client4_0_writev_cbk] 0-patchy-client-0: remote operation failed [Invalid argument]
[2019-02-25 15:08:41.019941] W [fuse-bridge.c:1436:fuse_err_cbk] 0-glusterfs-fuse: 17: FLUSH() ERR => -1 (Invalid argument)

Snippets of the strace dd command log
read(0, "`)\17\3713\251\213i\25E\10^\17&\"\244t\352h\340^3\233G\371\245\260:w\377\2732"..., 1048576) = 1048576
write(1, "`)\17\3713\251\213i\25E\10^\17&\"\244t\352h\340^3\233G\371\245\260:w\377\2732"..., 1048576) = 1048576
close(0)                                = 0
close(1)                                = -1 EINVAL (Invalid argument)