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Date: Fri, 2 Feb 2024 15:38:06 -0800
From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: Hamza Mahfooz <hamza.mahfooz@amd.com>
Cc: linux-kernel@vger.kernel.org, stable@vger.kernel.org,
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Subject: Re: [PATCH 1/3] driver core: bus: introduce can_remove()
Message-ID: <2024020224-unsoiled-velcro-86af@gregkh>
References: <20240202222603.141240-1-hamza.mahfooz@amd.com>
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In-Reply-To: <20240202222603.141240-1-hamza.mahfooz@amd.com>

On Fri, Feb 02, 2024 at 05:25:54PM -0500, Hamza Mahfooz wrote:
> Currently, drivers have no mechanism to block requests to unbind
> devices.

And that is by design.

> However, this can cause resource leaks and leave the device in
> an inconsistent state, such that rebinding the device may cause a hang
> or otherwise prevent the device from being rebound.

That is a driver bug, please fix your driver.

> So, introduce the can_remove() callback to allow drivers to indicate
> if it isn't appropriate to remove a device at the given time.

Nope, sorry, the driver needs to be fixed.

What broken driver are you needing this for?

Also realize, only root can unbind drivers (and it can also unload
modules), so if the root user really wants to do this, it can, and
should be possible to.

sorry,

greg k-h