Re: [Outreachy kernel] Trying to use Coccinelle

[Lourdes Pedrajas <lu@pplo.net>]

On Thu, Mar 12, 2020 at 12:23:48AM +0100, Stefano Brivio wrote:
> On Wed, 11 Mar 2020 19:11:34 +0100
> Lourdes Pedrajas <lu@pplo.net> wrote:
> 
> > Hello, I compiled Coccinelle successfully but maybe I am not getting it.
> > In order to try it in drivers/staging I ran e.g.:
> > 
> > make coccicheck MODE=patch M=drivers/staging/android/
> > 
> > and then got:
> > 
> > coccicheck failed
> > make: *** [coccicheck] Error 255
> > Makefile:1740: recipe for target 'coccicheck' failed.
> > 
> > Also tried some modifications of the command, read this documentation:
> > https://www.kernel.org/doc/html/latest/dev-tools/coccinelle.html and searched
> > how to use it, but nothing did help.
> > 
> > Only when I ran make coccicheck MODE=patch over entire sources it
> > produces some good results, but eventually I got
> > 
> > coccicheck failed
> > Makefile:1740: recipe for target 'coccicheck' failed
> > make: *** [coccicheck] Error 255
> 
> Can you share a bit more output? What comes before that?
> 
> -- 
> Stefano
> 

Hi Stefano,

Indeed, this is all the output: (this command is run in the sources root
directory)

make coccicheck MODE=patch J=8 M=drivers/staging/android/

Please check for false positives in the output before submitting a patch.
When using "patch" mode, carefully review the patch before submitting it.

coccicheck failed
Makefile:1740: recipe for target 'coccicheck' failed
make: *** [coccicheck] Error 255

Maybe I should try to use the distribution package instead? The
compilation wasn't smooth either, it gave me some autoconf errors I eventually
solved. However, if I run this command to compile all sources, it works, prints
some patches for the drivers/ directory in the standard output, but after a
little (and before descending to drivers/staging/ directory), it gives the same
error (I will skip some output and only copy the last patch it produces):

make coccicheck MODE=patch J=8

Please check for false positives in the output before submitting a patch.
When using "patch" mode, carefully review the patch before submitting it.

... (output skipped - various patches)

diff -u -p a/drivers/s390/crypto/zcrypt_ep11misc.c b/drivers/s390/crypto/zcrypt_ep11misc.c
--- a/drivers/s390/crypto/zcrypt_ep11misc.c
+++ b/drivers/s390/crypto/zcrypt_ep11misc.c
@@ -195,11 +195,10 @@ static inline struct ep11_cprb *alloc_cp
        size_t len = sizeof(struct ep11_cprb) + payload_len;
        struct ep11_cprb *cprb;

-       cprb = kmalloc(len, GFP_KERNEL);
+       cprb = kzalloc(len, GFP_KERNEL);
        if (!cprb)
                return NULL;

-       memset(cprb, 0, len);
        cprb->cprb_len = sizeof(struct ep11_cprb);
        cprb->cprb_ver_id = 0x04;
        memcpy(cprb->func_id, "T4", 2);
coccicheck failed
Makefile:1740: recipe for target 'coccicheck' failed
make: *** [coccicheck] Error 255

Maybe I am not using the command properly? I searched how to do it and
didn't get it, sorry :(

Thank you for your help!