On Wed, Sep 30, 2020 at 03:09:05PM +0100, antlists wrote: > So my guess was spot on :-) > > You'll guess that this is a common problem, with a well-known solution... > > https://raid.wiki.kernel.org/index.php/Easy_Fixes#Debian_9_and_Ubuntu OK, I've just retried with a new version of mdadm, mdadm - v4.1 - 2018-10-01 - which I think is roughly contemporaneous to the kernel version I'm using. But the problem still persists (with the exact same symptoms and details). I have one additional piece of information which might be relevant: when the mdadm --grow command is run, the kernel thread "md112_raid5" (where md112 is, of course, the md device number in my case) is replaced by two new ones, "md112_raid6" and "md112_reshape". Both remain in 'S' state. Looking into /proc/$pid/wchan, the former is in md_thread while the latter is in md_do_sync. Cheers, -- David A. Madore ( http://www.madore.org/~david/ )
