linux-kernel - Re: [PATCH 07/10] printk: Remove the now superfluous sentinel elements from ctl

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Message-ID: <20231204085628.pf7yxppacf4pm2cv@localhost>
Date:   Mon, 4 Dec 2023 09:56:28 +0100
From:   Joel Granados <j.granados@...sung.com>
To:     Petr Mladek <pmladek@...e.com>
CC:     Luis Chamberlain <mcgrof@...nel.org>, <willy@...radead.org>,
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Subject: Re: [PATCH 07/10] printk: Remove the now superfluous sentinel
 elements from ctl_table array

Hey Petr

I missed this message somehow....

On Tue, Nov 28, 2023 at 03:07:43PM +0100, Petr Mladek wrote:
> On Tue 2023-11-07 14:45:07, Joel Granados via B4 Relay wrote:
> > From: Joel Granados <j.granados@...sung.com>
> > 
> > This commit comes at the tail end of a greater effort to remove the
> > empty elements at the end of the ctl_table arrays (sentinels) which
> > will reduce the overall build time size of the kernel and run time
> > memory bloat by ~64 bytes per sentinel (further information Link :
> > https://lore.kernel.org/all/ZO5Yx5JFogGi%2FcBo@bombadil.infradead.org/)
> > 
> > rm sentinel element from printk_sysctls
> > 
> > Signed-off-by: Joel Granados <j.granados@...sung.com>
> 
> I am a bit sceptical if the size and time reduction is worth the
> effort. I feel that this change makes the access a bit less secure.
In what way "less secure"? Can you expand on that?

Notice that if you pass a pointer to the register functions, you will
get a warning/error on compilation.

> 
> Well, almost all arrays are static so that it should just work.
> The patch does what it says. Feel free to use:
Thx for the review. will do.

> 
> Reviewed-by: Petr Mladek <pmladek@...e.com>
> 
> Best Regards,
> Petr

-- 

Joel Granados

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