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Date: Thu, 18 Dec 2025 12:33:05 +0100
From: Greg KH <gregkh@linuxfoundation.org>
To: Haoxiang Li <lihaoxiang@isrc.iscas.ac.cn>
Cc: rafael@kernel.org, lenb@kernel.org, linux-acpi@vger.kernel.org,
	linux-kernel@vger.kernel.org, stable@vger.kernel.org
Subject: Re: [PATCH] PNP: add a error handling in pnpacpi_init()
Message-ID: <2025121841-unwoven-twelve-e65b@gregkh>
References: <20251218082903.551296-1-lihaoxiang@isrc.iscas.ac.cn>
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In-Reply-To: <20251218082903.551296-1-lihaoxiang@isrc.iscas.ac.cn>

On Thu, Dec 18, 2025 at 04:29:03PM +0800, Haoxiang Li wrote:
> Add a error handling for pnp_register_protocol(), and if
> it fails, call put_device() to drop the device reference.
> 
> Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
> Cc: stable@vger.kernel.org
> Signed-off-by: Haoxiang Li <lihaoxiang@isrc.iscas.ac.cn>
> ---
>  drivers/pnp/pnpacpi/core.c | 5 ++++-
>  1 file changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/pnp/pnpacpi/core.c b/drivers/pnp/pnpacpi/core.c
> index a0927081a003..0b63e1748b7c 100644
> --- a/drivers/pnp/pnpacpi/core.c
> +++ b/drivers/pnp/pnpacpi/core.c
> @@ -304,7 +304,10 @@ static int __init pnpacpi_init(void)
>  		return 0;
>  	}
>  	printk(KERN_INFO "pnp: PnP ACPI init\n");
> -	pnp_register_protocol(&pnpacpi_protocol);
> +	if (pnp_register_protocol(&pnpacpi_protocol)) {
> +		put_device(&pnpacpi_protocol.dev);

Again, this looks really wrong.

What tool are you all using to "find" these issues?  Why aren't you
properly documenting it?

thanks,

greg k-h