linux-kernel - Re: [PATCH v2 1/2] i3c: Remove the const qualifier from i2c_msg pointer in i2c

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <f9f730b6-4620-49dd-9700-ee18f777045f@t-8ch.de>
Date: Tue, 4 Feb 2025 10:50:34 +0100
From: Thomas Weißschuh <linux@...ssschuh.net>
To: Billy Tsai <billy_tsai@...eedtech.com>
Cc: alexandre.belloni@...tlin.com, pgaj@...ence.com, 
	miquel.raynal@...tlin.com, conor.culhane@...vaco.com, aniketmaurya@...gle.com, 
	Shyam-sundar.S-k@....com, jarkko.nikula@...ux.intel.com, wsa+renesas@...g-engineering.com, 
	xiaopei01@...inos.cn, Guruvendra.Punugupati@....com, linux-i3c@...ts.infradead.org, 
	linux-kernel@...r.kernel.org, BMC-SW@...eedtech.com
Subject: Re: [PATCH v2 1/2] i3c: Remove the const qualifier from i2c_msg
 pointer in i2c_xfers API

Hi Billy,

On 2025-02-04 17:17:01+0800, Billy Tsai wrote:
> The change is necessary to enable the use of the
> `i2c_get_dma_safe_msg_buf()` API, which requires a non-const
> `struct i2c_msg *` to operate. The `i2c_get_dma_safe_msg_buf()` function
> ensures safe handling of I2C messages when using DMA, making it essential
> for scenarios where DMA transfers are involved. By removing the `const`
> qualifier, this patch allows drivers to prepare and manage DMA-safe
> buffers directly.

This is missing a changelog to v1 of the series.

Also I asked before why it is not possible to change the signature of
i2c_get_dma_safe_msg_buf() to accept 'const struct i2c_msg *' [0].
That looks like the nicer solution to me.

> Signed-off-by: Billy Tsai <billy_tsai@...eedtech.com>
> ---
>  drivers/i3c/master/dw-i3c-master.c     | 2 +-
>  drivers/i3c/master/i3c-master-cdns.c   | 2 +-
>  drivers/i3c/master/mipi-i3c-hci/core.c | 2 +-
>  drivers/i3c/master/svc-i3c-master.c    | 2 +-
>  include/linux/i3c/master.h             | 2 +-
>  5 files changed, 5 insertions(+), 5 deletions(-)

<snip>

[0] https://lore.kernel.org/lkml/23854752-435e-432e-ba21-caf690c0cecc@t-8ch.de/