linux-kernel - Re: [patch] mm, mempolicy: make mpol_to

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]

Date:	Tue, 24 Sep 2013 20:18:16 -0700 (PDT)
From:	David Rientjes <rientjes@...gle.com>
To:	Dave Jones <davej@...hat.com>,
	Andrew Morton <akpm@...ux-foundation.org>,
	KOSAKI Motohiro <kosaki.motohiro@...fujitsu.com>,
	Chen Gang <gang.chen@...anux.com>,
	Rik van Riel <riel@...hat.com>, linux-kernel@...r.kernel.org,
	linux-mm@...ck.org
Subject: Re: [patch] mm, mempolicy: make mpol_to_str robust and always
 succeed

On Tue, 24 Sep 2013, Dave Jones wrote:

>  >  	case MPOL_BIND:
>  > -		/* Fall through */
>  >  	case MPOL_INTERLEAVE:
>  >  		nodes = pol->v.nodes;
>  >  		break;
> 
> Any reason not to leave this ?
> 
> "missing break" is the 2nd most common thing that coverity picks up.
> Most of them are false positives like the above, but the lack of annotations
> in our source makes it time-consuming to pick through them all to find the
> real bugs.
> 

Check out things like drivers/mfd/wm5110-tables.c that do things like

	switch (reg) {
	case ARIZONA_SOFTWARE_RESET:
	case ARIZONA_DEVICE_REVISION:
	case ARIZONA_CTRL_IF_SPI_CFG_1:
	case ARIZONA_CTRL_IF_I2C1_CFG_1:
	case ARIZONA_CTRL_IF_I2C2_CFG_1:
	case ARIZONA_CTRL_IF_I2C1_CFG_2:
	case ARIZONA_CTRL_IF_I2C2_CFG_2:
	...

and that file has over 1,000 case statements.  Having a

	/* fall through */

for all of them would be pretty annoying.

I don't remember any coding style rule about this (in fact 
Documentation/CodingStyle has examples of case statements without such a 
comment), I think it's just personal preference so I'll leave it to Andrew 
and what he prefers.

(And if he prefers the /* fall through */ then we should ask that it be 
added to checkpatch.pl since it warns about a million other things and not 
this.)
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/