The Problem
User is unable to mount xfs with noacl permission. noactl mount option for xfs file system is set in /etc/fstab file.
# cat /etc/fstab /dev/sbb1 /mnt xfs inode64.noacl 0 0
But mounting failed with error below.
# mount -v /mnt mount: wrong fs type, bad option, bad superblock on /dev/mapper/vg_cdm_ebsul06_N00-appl_ptch, missing codepage or helper program, or other error In some cases useful info is found in syslog - try
The dmesg errors for the noacl option are as follows:
# dmesg | tail XFS (sbb1): Ending clean mount XFS (sbb1): unknown mount option [noacl]. XFS (sbb1): Mounting Filesystem XFS (sbb1): Ending clean mount XFS (sbb1): unknown mount option [noacl]. XFS (sbb1): unknown mount option [noacl]. XFS (sbb1): unknown mount option [noacl]. XFS (sbb1): Mounting Filesystem XFS (sbb1): Ending clean mount XFS (sbb1): unknown mount option [noacl].
Although user can remount the XFS filessytem with noacl option successfully.
# mount -o remount,noacl /mnt # mount| grep noacl /dev/sdb1 on /mnt type xfs (rw,inode64,noacl)
The Solution
1. Currently, kernel is compiled with ACL support, so there is no option to disable ACL for XFS at runtime:
CONFIG_XFS_POSIX_ACL=y
2. For xfs remount , you can even specify any invalid options, like ‘hello’, XFS will ignore it but only list it in the output:
# mount -o remount,hello /mnt # mount .. /dev/sdb1 on /mnt/ type xfs (rw,noacl,noacl,noacl,hello)
3. And per source code for XFS, xfs simply ignore those invalid options:
xfs_fs_remount( ... * Until that is implemented we return success for * every remount request, and silently ignore all * options that we can't actually change. */ ...
Conclusion
There is no option to disable ACL for XFS at runtime. Do not set any ACL on files on xfs mount, ACL won’t be used for those files.