Received-SPF: pass (google.com: domain of linux-kernel+bounces-7181-linux.lists.archive=gmail.com@vger.kernel.org designates 2604:1380:45d1:ec00::1 as permitted sender) client-ip=2604:1380:45d1:ec00::1;
Date: Wed, 20 Dec 2023 17:40:42 +0200
From: Andy Shevchenko <andriy.shevchenko@intel.com>
To: Hugo Villeneuve <hugo@hugovil.com>
Cc: gregkh@linuxfoundation.org, jirislaby@kernel.org, jringle@gridpoint.com,
	kubakici@wp.pl, phil@raspberrypi.org, bo.svangard@embeddedart.se,
	linux-kernel@vger.kernel.org, linux-serial@vger.kernel.org,
	Hugo Villeneuve <hvilleneuve@dimonoff.com>, stable@vger.kernel.org,
	Yury Norov <yury.norov@gmail.com>
Subject: Re: [PATCH 02/18] serial: sc16is7xx: fix invalid sc16is7xx_lines
 bitfield in case of probe error
Message-ID: <ZYMK-l03S86Nw19I@smile.fi.intel.com>
References: <20231219171903.3530985-1-hugo@hugovil.com>
 <20231219171903.3530985-3-hugo@hugovil.com>
Precedence: bulk
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <20231219171903.3530985-3-hugo@hugovil.com>
Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo

On Tue, Dec 19, 2023 at 12:18:46PM -0500, Hugo Villeneuve wrote:
> From: Hugo Villeneuve <hvilleneuve@dimonoff.com>
> 
> If an error occurs during probing, the sc16is7xx_lines bitfield may be left
> in a state that doesn't represent the correct state of lines allocation.
> 
> For example, in a system with two SC16 devices, if an error occurs only
> during probing of channel (port) B of the second device, sc16is7xx_lines
> final state will be 00001011b instead of the expected 00000011b.
> 
> This is caused in part because of the "i--" in the for/loop located in
> the out_ports: error path.
> 
> Fix this by checking the return value of uart_add_one_port() and set line
> allocation bit only if this was successful. This allows the refactor of
> the obfuscated for(i--...) loop in the error path, and properly call
> uart_remove_one_port() only when needed, and properly unset line allocation
> bits.
> 
> Also use same mechanism in remove() when calling uart_remove_one_port().

Yes, this seems to be the correct one to fix the problem described in
the patch 1. I dunno why the patch 1 even exists.

As for Yury's patch, you are doing fixes, so your stuff has priority on his.

-- 
With Best Regards,
Andy Shevchenko