Comment 18 for bug 1748689

I confirm on kernels 4.15.0.19 and 4.15.0.20.

root@CmsrvLAP2:~# umount /media/Cmsrv*
root@CmsrvLAP2:~# mount -l | grep cifs
root@CmsrvLAP2:~# mount -a
root@CmsrvLAP2:~# dmesg | tail
[ 5.353312] CIFS VFS: ioctl error in smb2_get_dfs_refer rc=-5
[ 5.354716] CIFS VFS: ioctl error in smb2_get_dfs_refer rc=-5
[ 5.358145] CIFS VFS: ioctl error in smb2_get_dfs_refer rc=-5
[ 50.748155] random: crng init done
[ 61.625333] CIFS VFS: ioctl error in smb2_get_dfs_refer rc=-5
[ 61.632086] CIFS VFS: ioctl error in smb2_get_dfs_refer rc=-5
[ 61.652427] CIFS VFS: ioctl error in smb2_get_dfs_refer rc=-5
[ 61.661496] CIFS VFS: ioctl error in smb2_get_dfs_refer rc=-5
[ 61.900523] CIFS VFS: ioctl error in smb2_get_dfs_refer rc=-5
[ 61.909087] CIFS VFS: ioctl error in smb2_get_dfs_refer rc=-5
root@CmsrvLAP2:~# uname -a
Linux CmsrvLAP2 4.15.0-20-generic #21-Ubuntu SMP Tue Apr 24 06:16:15 UTC 2018 x86_64 x86_64 x86_64 GNU/Linux
root@CmsrvLAP2:~# mount -l | grep cifs
//x.x.x.x/C$ on /media/CmsrvAPP2-C type cifs (rw,relatime,vers=3.0,cache=strict,username=xxx,domain=xxx.xx,uid=0,noforceuid,gid=0,noforcegid,addr=xxx,file_mode=0755,dir_mode=0755,soft,nounix,mapposix,rsize=1048576,wsize=1048576,echo_interval=60,actimeo=1)
...