Re: [PATCH 12/14] s390/sclp_ftp: Replace get_zeroed_page() with kzalloc()

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential
issue to consider:
- [Low] s390/sclp_ftp: unnecessary unsigned long casts in
  sclp_ftp_startup()
--

commit a25923b8503ee3e56046245296e0025552cfe251
Author: Mike Rapoport (Microsoft) <rppt@kernel.org>

s390/sclp_ftp: Replace get_zeroed_page() with kzalloc()

This commit replaces get_zeroed_page() and free_page() with kzalloc() and
kfree() in sclp_ftp_et7() and sclp_ftp_startup().

Link: https://lore.kernel.org/all/635405e4-9423-4a25-a6e7-e03c8ea0bcbe@redhat.com

> diff --git a/drivers/s390/char/sclp_ftp.c b/drivers/s390/char/sclp_ftp.c
> index 853492d53953c..c46fd056e9daf 100644
> --- a/drivers/s390/char/sclp_ftp.c
> +++ b/drivers/s390/char/sclp_ftp.c

[ ... ]

> @@ -250,7 +250,7 @@ int sclp_ftp_startup(void)
>  		return rc;
>  
>  #ifdef DEBUG
> -	info = get_zeroed_page(GFP_KERNEL);
> +	info = (unsigned long)kzalloc(PAGE_SIZE, GFP_KERNEL);
>  
>  	if (info != 0) {
>  		struct sysinfo_2_2_2 *info222 = (struct sysinfo_2_2_2 *)info;
> @@ -262,7 +262,7 @@ int sclp_ftp_startup(void)
>  				 info222->lpar_number, info222->name);
>  		}
>  
> -		free_page(info);
> +		kfree((void *)info);
>  	}
>  #endif	/* DEBUG */
>  	return 0;

[Severity: Low]
This isn't a bug, but since the commit message notes that kmalloc() avoids
ugly casts, could info be replaced directly with struct sysinfo_2_2_2
*info222 here?  info was only declared as unsigned long for
get_zeroed_page() and free_page(), and keeping it as unsigned long adds
two new casts in addition to the existing struct sysinfo_2_2_2 * cast.

Also, the commit message says sclp_ftp_startup() allocates an SCCB to read
SCLP info, whereas this buffer is a struct sysinfo_2_2_2 (SYSIB 2.2.2)
passed to stsi().

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20261108-s390-sclp-ready-v1-0-3e7c90eb6676@kernel.org?part=12