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Date: Fri, 24 Nov 2023 15:05:47 +0000
From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: Oleksij Rempel <o.rempel@pengutronix.de>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>,
	Ulf Hansson <ulf.hansson@linaro.org>,
	Mark Brown <broonie@kernel.org>, kernel@pengutronix.de,
	linux-kernel@vger.kernel.org, linux-mmc@vger.kernel.org,
	linux-pm@vger.kernel.org,
	=?iso-8859-1?Q?S=F8ren?= Andersen <san@skov.dk>
Subject: Re: [PATCH v1 0/3] introduce priority-based shutdown support
Message-ID: <2023112403-laxative-lustiness-6a7f@gregkh>
References: <20231124145338.3112416-1-o.rempel@pengutronix.de>
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In-Reply-To: <20231124145338.3112416-1-o.rempel@pengutronix.de>

On Fri, Nov 24, 2023 at 03:53:35PM +0100, Oleksij Rempel wrote:
> Hi,
> 
> This patch series introduces support for prioritized device shutdown.
> The main goal is to enable prioritization for shutting down specific
> devices, particularly crucial in scenarios like power loss where
> hardware damage can occur if not handled properly.

Oh fun, now we will have drivers and subsystems fighting over their
priority, with each one insisting that they are the most important!

/s

Anyway, this is ripe for problems and issues in the long-run, what is so
special about this hardware that it can not just shutdown in the
existing order that it has to be "first" over everyone else?  What
exactly does this prevent and what devices are requiring this?

And most importantly, what has changed in the past 20+ years to
suddenly require this new functionality and how does any other operating
system handle it?

thanks,

greg k-h