On Mon, Aug 10, 2020 at 03:46:15PM +0200, Uwe Kleine-König wrote:
> >  umount() {
> > +	# make sure rc-once generated data makes it to the medium
> > +	sync
> >  	if ! mount_root_restore; then
> >  		# remounting rw/ro during the second boot will flush anything
> >  		# left in the filesystem journal
> 
> I would expect that the mount -o remount,ro that is done (sometimes) as
> part of mount_root_restore should handle this just fine.

In my case the system is always booted rw, so remounting ro doesn't
happen here at all, the script exits and the labgrid server powers the
board off before the data is written to disk.

Most other systems mount / ro, so remounting happens here and acts as a
flush barrier.

rsc
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