Re: Spinning down sata disk before poweroff

[Anindya Mukherjee <anindya49%hotmail.com@localhost>]

I submitted a new PR: #51252

> Doing the poweroff in wdlastclose() is bad because then you'll have a
> poweroff/powerup cycle for a reboot, or even on unmount/mount events if this
> is not your root device. This can be harmful for some disks (this has already
> been discussed).

Yes, I can confirm this is a problem; cannot  have an unconditional
wd_standby() call in wdlastclose() after flushing. The idea of wrapping the
reboot state in a flag and checking it sounds good.

I didn't yet have a chance to try the last patch.

> I'd prefer to have it the other way round then: a DETACH_POWEROFF
> which is set only for halt -p.
> 

Yes that would be ideal.