From mboxrd@z Thu Jan  1 00:00:00 1970
From: Logan Gunthorpe <logang-OTvnGxWRz7hWk0Htik3J/w@public.gmane.org>
Subject: Re: [PATCH v2 01/16] chardev: add helper function to register char
 devs with a struct device
Date: Mon, 27 Feb 2017 20:27:44 -0700
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On 27/02/17 09:56 AM, Jason Gunthorpe wrote:
> Yes please, that is way too subtle. Suggest:
> 
> NOTE: Callers must assume that userspace was able to open the cdev and
> can call cdev fops callbacks at any time, even if this function fails.
> 
> I would also add a note to cdev_device_del:
> 
> NOTE: This guarantees that associated sysfs callbacks are not running
> or runnable, however any open cdevs will remain and their fops remain
> callable even after this returns.
> 
> Since I have seen a lot of confusion on that point as well..

Sure, I'll add that verbiage to a v3 sometime after rc1.

Logan