Re: [PATCH v3 1/4] remoteproc: core: Move cdev add before device add

From: Greg KH <gregkh@linuxfoundation.org>
To: Siddharth Gupta <sidgup@codeaurora.org>
Cc: bjorn.andersson@linaro.org, ohad@wizery.com,
	linux-remoteproc@vger.kernel.org, linux-kernel@vger.kernel.org,
	linux-arm-msm@vger.kernel.org,
	linux-arm-kernel@lists.infradead.org, psodagud@codeaurora.org,
	stable@vger.kernel.org
Subject: Re: [PATCH v3 1/4] remoteproc: core: Move cdev add before device add
Date: Tue, 15 Jun 2021 06:54:00 +0200	[thread overview]
Message-ID: <YMgyaC9k/3gP2SCW@kroah.com> (raw)
In-Reply-To: <1623723671-5517-2-git-send-email-sidgup@codeaurora.org>

On Mon, Jun 14, 2021 at 07:21:08PM -0700, Siddharth Gupta wrote:
> When cdev_add is called after device_add has been called there is no
> way for the userspace to know about the addition of a cdev as cdev_add
> itself doesn't trigger a uevent notification, or for the kernel to
> know about the change to devt. This results in two problems:
>  - mknod is never called for the cdev and hence no cdev appears on
>    devtmpfs.
>  - sysfs links to the new cdev are not established.
> 
> The cdev needs to be added and devt assigned before device_add() is
> called in order for the relevant sysfs and devtmpfs entries to be
> created and the uevent to be properly populated.
> 
> Signed-off-by: Siddharth Gupta <sidgup@codeaurora.org>
> Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
> ---
>  drivers/remoteproc/remoteproc_core.c | 10 +++++-----
>  1 file changed, 5 insertions(+), 5 deletions(-)

<formletter>

This is not the correct way to submit patches for inclusion in the
stable kernel tree.  Please read:
    https://www.kernel.org/doc/html/latest/process/stable-kernel-rules.html
for how to do this properly.

</formletter>