Re: [PATCH] mm: honor FOLL_GET flag in follow_hugetlb_page v2

2013-05-08 Thread KOSAKI Motohiro
>> Why? The following bug_on inhibit both case. > > Yes i get lost on the double negation, but still my patch is correct > and i am not using gup but follow_hugetlb_page directly and i run into > the issue. My patch does not change the behavior for current user, > just fix assumption new user might

Re: [PATCH] mm: honor FOLL_GET flag in follow_hugetlb_page v2

2013-05-08 Thread Jerome Glisse
On Tue, May 7, 2013 at 10:41 PM, KOSAKI Motohiro wrote: > On Tue, May 7, 2013 at 8:51 PM, Jerome Glisse wrote: >> On Tue, May 7, 2013 at 8:47 PM, KOSAKI Motohiro >> wrote: >>> On Tue, May 7, 2013 at 6:58 PM, wrote: From: Jerome Glisse Do not increase page count if FOLL_GET is n

Re: [PATCH] mm: honor FOLL_GET flag in follow_hugetlb_page v2

2013-05-07 Thread KOSAKI Motohiro
On Tue, May 7, 2013 at 8:51 PM, Jerome Glisse wrote: > On Tue, May 7, 2013 at 8:47 PM, KOSAKI Motohiro > wrote: >> On Tue, May 7, 2013 at 6:58 PM, wrote: >>> From: Jerome Glisse >>> >>> Do not increase page count if FOLL_GET is not set. None of the >>> current user can trigger the issue becaus

Re: [PATCH] mm: honor FOLL_GET flag in follow_hugetlb_page v2

2013-05-07 Thread Jerome Glisse
On Tue, May 7, 2013 at 8:47 PM, KOSAKI Motohiro wrote: > On Tue, May 7, 2013 at 6:58 PM, wrote: >> From: Jerome Glisse >> >> 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 t

Re: [PATCH] mm: honor FOLL_GET flag in follow_hugetlb_page v2

2013-05-07 Thread KOSAKI Motohiro
On Tue, May 7, 2013 at 6:58 PM, wrote: > From: Jerome Glisse > > 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

[PATCH] mm: honor FOLL_GET flag in follow_hugetlb_page v2

2013-05-07 Thread j . glisse
From: Jerome Glisse 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'