lkml.org 
[lkml]   [2013]   [May]   [7]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
SubjectRe: [PATCH] mm: honor FOLL_GET flag in follow_hugetlb_page v2
From
On Tue, May 7, 2013 at 8:47 PM, KOSAKI Motohiro
<kosaki.motohiro@gmail.com> wrote:
> On Tue, May 7, 2013 at 6:58 PM, <j.glisse@gmail.com> wrote:
>> From: Jerome Glisse <jglisse@redhat.com>
>>
>> Do not increase page count if FOLL_GET is not set. None of the
>> current user can trigger the issue because none of the current
>> user call __get_user_pages with both the pages array ptr non
>> NULL and the FOLL_GET flags non set in other word all caller
>> of __get_user_pages that don't set the FOLL_GET flags also call
>> with pages == NULL.
>
> Because, __get_user_pages() doesn't allow pages==NULL and FOLL_GET is on.

Yes but this allow pages != NULL and FOLL_GET not set and as i said
there is no such user of that yet and this is exactly what i was
trying to use.

Cheers,
Jerome

>
> long __get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
> {
> (snip)
> VM_BUG_ON(!!pages != !!(gup_flags & FOLL_GET));


\
 
 \ /
  Last update: 2013-05-08 03:21    [W:0.049 / U:0.068 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site