Re: [PATCH] checkpatch: Test for kmalloc/memset(0) pairs

From: Julia Lawall <julia@diku.dk>
To: Pekka Enberg <penberg@kernel.org>
Cc: "Américo Wang" <xiyou.wangcong@gmail.com>,
	"Steven Rostedt" <rostedt@goodmis.org>,
	"Jonathan Corbet" <corbet@lwn.net>,
	LKML <linux-kernel@vger.kernel.org>,
	"Andy Whitcroft" <apw@shadowen.org>,
	"Dave Jones" <davej@redhat.com>,
	"Andrew Morton" <akpm@linux-foundation.org>,
	"Nicolas Palix" <npalix@diku.dk>, "Ingo Molnar" <mingo@elte.hu>
Subject: Re: [PATCH] checkpatch: Test for kmalloc/memset(0) pairs
Date: Sun, 20 Mar 2011 10:17:07 +0100 (CET)	[thread overview]
Message-ID: <Pine.LNX.4.64.1103201007430.28495@ask.diku.dk> (raw)
In-Reply-To: <AANLkTi=MMKvA-9pFiM1K_JSXjS71JLRCem8THnhu-0=N@mail.gmail.com>

On Sun, 20 Mar 2011, Pekka Enberg wrote:

> Hi Julia,
> 
> On Sun, Mar 20, 2011 at 10:01 AM, Julia Lawall <julia@diku.dk> wrote:
> > Suggestions for how to make it easier to use or the documentation more
> > understandable are welcome.
> 
> The benefit of scripts/checkpatch.pl is that it doesn't require any
> setting up to do. I'm personally less likely to use Coccinelle (and
> Sparse for that matter) on boxes where the software is not installed.
> I'm not sure how other people feel about it, but I'd personally love
> to see tools/coccinelle and tools/sparse.

This was discussed before, and it was felt that perhaps 75000 lines of 
ocaml code was not really appropriate for the Linux source tree, and also 
that it would too much complicate our development process.

One reason for using multiple machines would be to work on multiple 
architectures.  But Coccinelle is not sensitive to the architecture on 
which it is run, so perhaps you do't need to have it installed everywhere.

> As for something more concrete, I guess this is what I'm mostly interested in:
> 
> penberg@jaguar:~/src/linux$ make C=1 CHECK="scripts/coccicheck" mm/slub.o
> 
> I guess it'd be good to document that for 'make help' because now you
> need to dig through Documentation/coccinelle.txt to find it.

OK, thanks.  We will look into that.

> P.S. It seems there's a bug somewhere because the above command fails
> miserably for me:
> 
>   CHK     include/linux/version.h
>   CHK     include/generated/utsrelease.h
>   CALL    scripts/checksyscalls.sh
>   CHECK   mm/slub.c
> File "/home/penberg/src/linux/scripts/coccinelle/api/memdup_user.cocci",
> line 32, column 5,  charpos = 747
>     around = '<+...', whole content = -    <+... when != goto l2;
> Fatal error: exception Lexer_cocci.Lexical("invalid in a nonempty
> context: <+...")
> File "/home/penberg/src/linux/scripts/coccinelle/api/memdup_user.cocci",
> line 32, column 5,  charpos = 747
>     around = '<+...', whole content = -    <+... when != goto l2;
> Fatal error: exception Lexer_cocci.Lexical("invalid in a nonempty
> context: <+...")
> File "/home/penberg/src/linux/scripts/coccinelle/api/memdup_user.cocci",
> line 32, column 5,  charpos = 747
>     around = '<+...', whole content = -    <+... when != goto l2;
> Fatal error: exception Lexer_cocci.Lexical("invalid in a nonempty
> context: <+...")
> File "/home/penberg/src/linux/scripts/coccinelle/api/memdup_user.cocci",
> line 32, column 5,  charpos = 747
>     around = '<+...', whole content = -    <+... when != goto l2;
> Fatal error: exception Lexer_cocci.Lexical("invalid in a nonempty
> context: <+...")
> make[1]: *** [mm/slub.o] Error 1
> make: *** [mm/slub.o] Error 2
> 
> penberg@jaguar:~/src/linux$ dpkg -l|grep coccinelle
> ii  coccinelle                                      0.2.2.deb-2
>                                         semantic patching tool for C
> 
> [ I'm on Ubuntu 10.10. ]

Indeed that one seems to be quite out of date.  You can get the most 
recent version here: https://launchpad.net/~npalix/+archive/coccinelle

julia