Re: [GIT PULL] xfs: new code for 5.11

[Darrick J. Wong]

On Tue, Dec 29, 2020 at 10:49:55AM +0300, Dmitrii Tcvetkov wrote:
> >Please pull the following branch containing all the new xfs code for
> >5.11.  In this release we add the ability to set a 'needsrepair' flag
> >indicating that we /know/ the filesystem requires xfs_repair, but other
> >than that, it's the usual strengthening of metadata validation and
> >miscellaneous cleanups.
> >...
> >New code for 5.11:
> >- Introduce a "needsrepair" "feature" to flag a filesystem as needing a
> >  pass through xfs_repair.  This is key to enabling filesystem upgrades
> >  (in xfs_db) that require xfs_repair to make minor adjustments to
> >metadata.
> 
> Hello.
> 
> Most likely I miss something obvious but according to xfs_repair(8):
> BUGS:
> The filesystem to be checked and repaired must have been unmounted
> cleanly  using  normal  system  administration  procedures (the
> umount(8)  command  or  system  shutdown),  not  as  a  result of a
> crash or system reset.  If the filesystem has not been unmounted
> cleanly, mount it and unmount it cleanly before running xfs_repair.
> 
> which is there since commit d321ceac "add libxlog directory"
> Date:   Wed Oct 17 11:00:32 2001 +0000 in xfsprogs-dev[1]. 
> 
> So will be there situation of uncleanly unmounted filesystem with
> "needsrepair" bit set?

No.  If we detect metadata corruption we stop writing metadata
and take the fs offline immediately.  We would not set needsrepair, for
exactly the reasons you outline.

--D

> Will one be able to mount and umount it before running xfs_repair in
> that case?
> 
> [1] git://git.kernel.org/pub/scm/fs/xfs/xfsprogs-dev.git