Re: [PATCH v2 07/10] mm, hugetlb: do not use a page in page cache for cow optimization

2013-07-24 Thread Joonsoo Kim
On Tue, Jul 23, 2013 at 01:45:50PM +0200, Michal Hocko wrote: > On Mon 22-07-13 17:36:28, Joonsoo Kim wrote: > > Currently, we use a page with mapped count 1 in page cache for cow > > optimization. If we find this condition, we don't allocate a new > > page and copy contents. Instead, we map this

Re: [PATCH v2 07/10] mm, hugetlb: do not use a page in page cache for cow optimization

2013-07-24 Thread Joonsoo Kim
On Tue, Jul 23, 2013 at 01:45:50PM +0200, Michal Hocko wrote: On Mon 22-07-13 17:36:28, Joonsoo Kim wrote: Currently, we use a page with mapped count 1 in page cache for cow optimization. If we find this condition, we don't allocate a new page and copy contents. Instead, we map this page

Re: [PATCH v2 07/10] mm, hugetlb: do not use a page in page cache for cow optimization

2013-07-23 Thread Michal Hocko
On Mon 22-07-13 17:36:28, Joonsoo Kim wrote: > Currently, we use a page with mapped count 1 in page cache for cow > optimization. If we find this condition, we don't allocate a new > page and copy contents. Instead, we map this page directly. > This may introduce a problem that writting to private

Re: [PATCH v2 07/10] mm, hugetlb: do not use a page in page cache for cow optimization

2013-07-23 Thread Michal Hocko
On Mon 22-07-13 17:36:28, Joonsoo Kim wrote: Currently, we use a page with mapped count 1 in page cache for cow optimization. If we find this condition, we don't allocate a new page and copy contents. Instead, we map this page directly. This may introduce a problem that writting to private

Re: [PATCH v2 07/10] mm, hugetlb: do not use a page in page cache for cow optimization

2013-07-22 Thread Naoya Horiguchi
On Mon, Jul 22, 2013 at 05:36:28PM +0900, Joonsoo Kim wrote: > Currently, we use a page with mapped count 1 in page cache for cow > optimization. If we find this condition, we don't allocate a new > page and copy contents. Instead, we map this page directly. > This may introduce a problem that

[PATCH v2 07/10] mm, hugetlb: do not use a page in page cache for cow optimization

2013-07-22 Thread Joonsoo Kim
Currently, we use a page with mapped count 1 in page cache for cow optimization. If we find this condition, we don't allocate a new page and copy contents. Instead, we map this page directly. This may introduce a problem that writting to private mapping overwrite hugetlb file directly. You can

[PATCH v2 07/10] mm, hugetlb: do not use a page in page cache for cow optimization

2013-07-22 Thread Joonsoo Kim
Currently, we use a page with mapped count 1 in page cache for cow optimization. If we find this condition, we don't allocate a new page and copy contents. Instead, we map this page directly. This may introduce a problem that writting to private mapping overwrite hugetlb file directly. You can

Re: [PATCH v2 07/10] mm, hugetlb: do not use a page in page cache for cow optimization

2013-07-22 Thread Naoya Horiguchi
On Mon, Jul 22, 2013 at 05:36:28PM +0900, Joonsoo Kim wrote: Currently, we use a page with mapped count 1 in page cache for cow optimization. If we find this condition, we don't allocate a new page and copy contents. Instead, we map this page directly. This may introduce a problem that