linux-kernel - Re: [PATCH] mm: gup: Re-define follow_page_mask output parameter page

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]

Message-ID: <20160713075024.GB28723@dhcp22.suse.cz>
Date:	Wed, 13 Jul 2016 09:50:24 +0200
From:	Michal Hocko <mhocko@...nel.org>
To:	Chen Gang <chengang@...ndsoft.com.cn>
Cc:	Andrew Morton <akpm@...ux-foundation.org>, vbabka@...e.cz,
	kirill.shutemov@...ux.intel.com, mingo@...nel.org,
	dave.hansen@...ux.intel.com, dan.j.williams@...el.com,
	hannes@...xchg.org, jack@...e.cz, iamjoonsoo.kim@....com,
	jmarchan@...hat.com, dingel@...ux.vnet.ibm.com, oleg@...hat.com,
	linux-mm@...ck.org, linux-kernel@...r.kernel.org,
	Chen Gang <gang.chen.5i5j@...il.com>
Subject: Re: [PATCH] mm: gup: Re-define follow_page_mask output parameter
 page_mask usage

On Wed 13-07-16 01:03:10, Chen Gang wrote:
> On 7/12/16 05:17, Andrew Morton wrote:
> > On Sun, 10 Jul 2016 01:17:05 +0800 chengang@...ndsoft.com.cn wrote:
> > 
> >> For a pure output parameter:
> >>
> >>  - When callee fails, the caller should not assume the output parameter
> >>    is still valid.
> >>
> >>  - And callee should not assume the pure output parameter must be
> >>    provided by caller -- caller has right to pass NULL when caller does
> >>    not care about it.
> > 
> > Sorry, I don't think this one is worth merging really.
> > 
> 
> OK, thanks, I can understand.
> 
> It will be better if provide more details: e.g.
> 
>  - This patch is incorrect, or the comments is not correct.
> 
>  - The patch is worthless, at present.

I would say the patch is not really needed. The code you are touching
works just fine and there is no reason to touch it unless this is a part
of a larger change where future changes would be easier to
review/implement.

-- 
Michal Hocko
SUSE Labs