linux-kernel - Re: [PATCH] mm/mmap.c: silence variable 'new

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:   Wed, 24 Jul 2019 10:11:05 -0400
From:   Qian Cai <cai@....pw>
To:     YueHaibing <yuehaibing@...wei.com>, akpm@...ux-foundation.org,
        kirill.shutemov@...ux.intel.com, mhocko@...e.com, vbabka@...e.cz,
        yang.shi@...ux.alibaba.com, jannh@...gle.com, walken@...gle.com
Cc:     linux-kernel@...r.kernel.org, linux-mm@...ck.org
Subject: Re: [PATCH] mm/mmap.c: silence variable 'new_start' set but not used

On Wed, 2019-07-24 at 22:07 +0800, YueHaibing wrote:
> 'new_start' is used in is_hugepage_only_range(),
> which do nothing in some arch. gcc will warning:
> 
> mm/mmap.c: In function acct_stack_growth:
> mm/mmap.c:2311:16: warning: variable new_start set but not used [-Wunused-but-
> set-variable]

Nope. Convert them to inline instead.

> 
> Reported-by: Hulk Robot <hulkci@...wei.com>
> Signed-off-by: YueHaibing <yuehaibing@...wei.com>
> ---
>  mm/mmap.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/mm/mmap.c b/mm/mmap.c
> index e2dbed3..56c2a92 100644
> --- a/mm/mmap.c
> +++ b/mm/mmap.c
> @@ -2308,7 +2308,7 @@ static int acct_stack_growth(struct vm_area_struct *vma,
>  			     unsigned long size, unsigned long grow)
>  {
>  	struct mm_struct *mm = vma->vm_mm;
> -	unsigned long new_start;
> +	unsigned long __maybe_unused new_start;
>  
>  	/* address space limit tests */
>  	if (!may_expand_vm(mm, vma->vm_flags, grow))