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 for <linuxppc-dev@lists.ozlabs.org>; Sat, 24 Sep 2016 11:37:32 +1000 (AEST)
Subject: Re: [RFC] fs: add userspace critical mounts event support
To: Dmitry Torokhov <dmitry.torokhov@gmail.com>,
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Date: Fri, 23 Sep 2016 18:37:28 -0700
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On 03/09/2016 11:10, Dmitry Torokhov wrote:
> I was thinking if we kernel could post
> "conditions" (maybe simple stings) that it waits for, and userspace
> could unlock these "conditions". One of them might be "firmware
> available".

On idea offered by Josh Triplett that seems to overlap with this one
is to have something similar to the (deprecated) userhelper with
*per-blob* requests and notifications except for one major difference:
userspace would not anymore be in charge of *providing* the blob but
would instead only *signal* when a given blob becomes available and is
either found or found missing. Then the kernel loads the blob _by
itself_; unlike the userhelper. No new “critical filesystem” concept
and a *per-blob basis*, allowing any variation of blob locations
across any number of initramfs and filesystems.

Could this one fly?