Re: [PATCH v1 0/2] mm/kdump: exclude reserved pages in dumps

2018-07-30 Thread David Hildenbrand
On 26.07.2018 21:50, Andrew Morton wrote: > On Thu, 26 Jul 2018 10:45:54 +0200 David Hildenbrand wrote: > >>> Does each user of PG_balloon check for PG_reserved? If this is the case >>> then yes this would be OK. >>> >> >> I can only spot one user of PageBalloon() at all (fs/proc/page.c) , >> whi

Re: [PATCH v1 0/2] mm/kdump: exclude reserved pages in dumps

2018-07-26 Thread Andrew Morton
On Thu, 26 Jul 2018 10:45:54 +0200 David Hildenbrand wrote: > > Does each user of PG_balloon check for PG_reserved? If this is the case > > then yes this would be OK. > > > > I can only spot one user of PageBalloon() at all (fs/proc/page.c) , > which makes me wonder if this bit is actually stil

Re: [PATCH v1 0/2] mm/kdump: exclude reserved pages in dumps

2018-07-26 Thread David Hildenbrand
On 26.07.2018 10:30, Michal Hocko wrote: > On Thu 26-07-18 10:22:41, David Hildenbrand wrote: >> On 24.07.2018 09:22, Michal Hocko wrote: >>> On Mon 23-07-18 19:12:58, David Hildenbrand wrote: On 23.07.2018 13:45, Vlastimil Babka wrote: > On 07/20/2018 02:34 PM, David Hildenbrand wrote: >>

Re: [PATCH v1 0/2] mm/kdump: exclude reserved pages in dumps

2018-07-26 Thread David Hildenbrand
On 26.07.2018 10:27, Michal Hocko wrote: > On Wed 25-07-18 16:20:41, David Hildenbrand wrote: >> On 25.07.2018 15:51, Michal Hocko wrote: >>> On Tue 24-07-18 16:13:09, David Hildenbrand wrote: >>> [...] So I see right now: - Pg_reserved + e.g. new page type (or some other unique iden

Re: [PATCH v1 0/2] mm/kdump: exclude reserved pages in dumps

2018-07-26 Thread Michal Hocko
On Thu 26-07-18 10:22:41, David Hildenbrand wrote: > On 24.07.2018 09:22, Michal Hocko wrote: > > On Mon 23-07-18 19:12:58, David Hildenbrand wrote: > >> On 23.07.2018 13:45, Vlastimil Babka wrote: > >>> On 07/20/2018 02:34 PM, David Hildenbrand wrote: > Dumping tools (like makedumpfile) right

Re: [PATCH v1 0/2] mm/kdump: exclude reserved pages in dumps

2018-07-26 Thread Michal Hocko
On Wed 25-07-18 16:20:41, David Hildenbrand wrote: > On 25.07.2018 15:51, Michal Hocko wrote: > > On Tue 24-07-18 16:13:09, David Hildenbrand wrote: > > [...] > >> So I see right now: > >> > >> - Pg_reserved + e.g. new page type (or some other unique identifier in > >> combination with Pg_reserve

Re: [PATCH v1 0/2] mm/kdump: exclude reserved pages in dumps

2018-07-26 Thread David Hildenbrand
On 24.07.2018 09:22, Michal Hocko wrote: > On Mon 23-07-18 19:12:58, David Hildenbrand wrote: >> On 23.07.2018 13:45, Vlastimil Babka wrote: >>> On 07/20/2018 02:34 PM, David Hildenbrand wrote: Dumping tools (like makedumpfile) right now don't exclude reserved pages. So reserved pages mig

Re: [PATCH v1 0/2] mm/kdump: exclude reserved pages in dumps

2018-07-25 Thread David Hildenbrand
On 25.07.2018 15:51, Michal Hocko wrote: > On Tue 24-07-18 16:13:09, David Hildenbrand wrote: > [...] >> So I see right now: >> >> - Pg_reserved + e.g. new page type (or some other unique identifier in >> combination with Pg_reserved) >> -> Avoid reads of pages we know are offline >> - extend is

Re: [PATCH v1 0/2] mm/kdump: exclude reserved pages in dumps

2018-07-25 Thread Michal Hocko
On Tue 24-07-18 16:13:09, David Hildenbrand wrote: [...] > So I see right now: > > - Pg_reserved + e.g. new page type (or some other unique identifier in > combination with Pg_reserved) > -> Avoid reads of pages we know are offline > - extend is_ram_page() > -> Fake zero memory for pages we kn

Re: [PATCH v1 0/2] mm/kdump: exclude reserved pages in dumps

2018-07-24 Thread David Hildenbrand
On 24.07.2018 15:35, Michal Hocko wrote: > On Tue 24-07-18 15:27:51, David Hildenbrand wrote: >> On 24.07.2018 15:13, Michal Hocko wrote: >>> On Tue 24-07-18 14:17:12, David Hildenbrand wrote: On 24.07.2018 09:25, Michal Hocko wrote: > On Mon 23-07-18 19:20:43, David Hildenbrand wrote: >>>

Re: [PATCH v1 0/2] mm/kdump: exclude reserved pages in dumps

2018-07-24 Thread Michal Hocko
On Tue 24-07-18 15:27:51, David Hildenbrand wrote: > On 24.07.2018 15:13, Michal Hocko wrote: > > On Tue 24-07-18 14:17:12, David Hildenbrand wrote: > >> On 24.07.2018 09:25, Michal Hocko wrote: > >>> On Mon 23-07-18 19:20:43, David Hildenbrand wrote: > On 23.07.2018 14:30, Michal Hocko wrote:

Re: [PATCH v1 0/2] mm/kdump: exclude reserved pages in dumps

2018-07-24 Thread David Hildenbrand
On 24.07.2018 15:13, Michal Hocko wrote: > On Tue 24-07-18 14:17:12, David Hildenbrand wrote: >> On 24.07.2018 09:25, Michal Hocko wrote: >>> On Mon 23-07-18 19:20:43, David Hildenbrand wrote: On 23.07.2018 14:30, Michal Hocko wrote: > On Mon 23-07-18 13:45:18, Vlastimil Babka wrote: >

Re: [PATCH v1 0/2] mm/kdump: exclude reserved pages in dumps

2018-07-24 Thread Michal Hocko
On Tue 24-07-18 14:17:12, David Hildenbrand wrote: > On 24.07.2018 09:25, Michal Hocko wrote: > > On Mon 23-07-18 19:20:43, David Hildenbrand wrote: > >> On 23.07.2018 14:30, Michal Hocko wrote: > >>> On Mon 23-07-18 13:45:18, Vlastimil Babka wrote: > On 07/20/2018 02:34 PM, David Hildenbrand

Re: [PATCH v1 0/2] mm/kdump: exclude reserved pages in dumps

2018-07-24 Thread Michal Hocko
On Tue 24-07-18 14:22:06, Vlastimil Babka wrote: > On 07/24/2018 01:19 PM, Michal Hocko wrote: > >> When creating a crashdump, I definitely need the pages containing memmap > >> included in the dump, so I can inspect the struct pages. But this is a > >> bit recursive issue, so I'll try making it cl

Re: [PATCH v1 0/2] mm/kdump: exclude reserved pages in dumps

2018-07-24 Thread David Hildenbrand
On 24.07.2018 14:22, Vlastimil Babka wrote: > On 07/24/2018 01:19 PM, Michal Hocko wrote: >>> When creating a crashdump, I definitely need the pages containing memmap >>> included in the dump, so I can inspect the struct pages. But this is a >>> bit recursive issue, so I'll try making it clearer: >

Re: [PATCH v1 0/2] mm/kdump: exclude reserved pages in dumps

2018-07-24 Thread Vlastimil Babka
On 07/24/2018 01:19 PM, Michal Hocko wrote: >> When creating a crashdump, I definitely need the pages containing memmap >> included in the dump, so I can inspect the struct pages. But this is a >> bit recursive issue, so I'll try making it clearer: >> >> 1) there are kernel pages with data (e.g. sl

Re: [PATCH v1 0/2] mm/kdump: exclude reserved pages in dumps

2018-07-24 Thread David Hildenbrand
On 24.07.2018 09:25, Michal Hocko wrote: > On Mon 23-07-18 19:20:43, David Hildenbrand wrote: >> On 23.07.2018 14:30, Michal Hocko wrote: >>> On Mon 23-07-18 13:45:18, Vlastimil Babka wrote: On 07/20/2018 02:34 PM, David Hildenbrand wrote: > Dumping tools (like makedumpfile) right now don'

Re: [PATCH v1 0/2] mm/kdump: exclude reserved pages in dumps

2018-07-24 Thread Michal Hocko
On Tue 24-07-18 11:47:02, Vlastimil Babka wrote: > On 07/23/2018 02:30 PM, Michal Hocko wrote: > > On Mon 23-07-18 13:45:18, Vlastimil Babka wrote: > >> On 07/20/2018 02:34 PM, David Hildenbrand wrote: > >>> Dumping tools (like makedumpfile) right now don't exclude reserved pages. > >>> So reserved

Re: [PATCH v1 0/2] mm/kdump: exclude reserved pages in dumps

2018-07-24 Thread Vlastimil Babka
On 07/24/2018 09:22 AM, Michal Hocko wrote: > On Mon 23-07-18 19:12:58, David Hildenbrand wrote: >> On 23.07.2018 13:45, Vlastimil Babka wrote: >>> On 07/20/2018 02:34 PM, David Hildenbrand wrote: Dumping tools (like makedumpfile) right now don't exclude reserved pages. So reserved pages

Re: [PATCH v1 0/2] mm/kdump: exclude reserved pages in dumps

2018-07-24 Thread Vlastimil Babka
On 07/23/2018 02:30 PM, Michal Hocko wrote: > On Mon 23-07-18 13:45:18, Vlastimil Babka wrote: >> On 07/20/2018 02:34 PM, David Hildenbrand wrote: >>> Dumping tools (like makedumpfile) right now don't exclude reserved pages. >>> So reserved pages might be access by dump tools although nobody except

Re: [PATCH v1 0/2] mm/kdump: exclude reserved pages in dumps

2018-07-24 Thread David Hildenbrand
On 24.07.2018 10:53, Michal Hocko wrote: > On Tue 24-07-18 10:46:20, David Hildenbrand wrote: >> On 24.07.2018 09:25, Michal Hocko wrote: >>> On Mon 23-07-18 19:20:43, David Hildenbrand wrote: On 23.07.2018 14:30, Michal Hocko wrote: > On Mon 23-07-18 13:45:18, Vlastimil Babka wrote: >

Re: [PATCH v1 0/2] mm/kdump: exclude reserved pages in dumps

2018-07-24 Thread Michal Hocko
On Tue 24-07-18 10:46:20, David Hildenbrand wrote: > On 24.07.2018 09:25, Michal Hocko wrote: > > On Mon 23-07-18 19:20:43, David Hildenbrand wrote: > >> On 23.07.2018 14:30, Michal Hocko wrote: > >>> On Mon 23-07-18 13:45:18, Vlastimil Babka wrote: > On 07/20/2018 02:34 PM, David Hildenbrand

Re: [PATCH v1 0/2] mm/kdump: exclude reserved pages in dumps

2018-07-24 Thread David Hildenbrand
On 24.07.2018 09:25, Michal Hocko wrote: > On Mon 23-07-18 19:20:43, David Hildenbrand wrote: >> On 23.07.2018 14:30, Michal Hocko wrote: >>> On Mon 23-07-18 13:45:18, Vlastimil Babka wrote: On 07/20/2018 02:34 PM, David Hildenbrand wrote: > Dumping tools (like makedumpfile) right now don'

Re: [PATCH v1 0/2] mm/kdump: exclude reserved pages in dumps

2018-07-24 Thread Michal Hocko
On Mon 23-07-18 19:20:43, David Hildenbrand wrote: > On 23.07.2018 14:30, Michal Hocko wrote: > > On Mon 23-07-18 13:45:18, Vlastimil Babka wrote: > >> On 07/20/2018 02:34 PM, David Hildenbrand wrote: > >>> Dumping tools (like makedumpfile) right now don't exclude reserved pages. > >>> So reserved

Re: [PATCH v1 0/2] mm/kdump: exclude reserved pages in dumps

2018-07-24 Thread Michal Hocko
On Mon 23-07-18 19:12:58, David Hildenbrand wrote: > On 23.07.2018 13:45, Vlastimil Babka wrote: > > On 07/20/2018 02:34 PM, David Hildenbrand wrote: > >> Dumping tools (like makedumpfile) right now don't exclude reserved pages. > >> So reserved pages might be access by dump tools although nobody e

Re: [PATCH v1 0/2] mm/kdump: exclude reserved pages in dumps

2018-07-23 Thread David Hildenbrand
On 23.07.2018 14:30, Michal Hocko wrote: > On Mon 23-07-18 13:45:18, Vlastimil Babka wrote: >> On 07/20/2018 02:34 PM, David Hildenbrand wrote: >>> Dumping tools (like makedumpfile) right now don't exclude reserved pages. >>> So reserved pages might be access by dump tools although nobody except >>

Re: [PATCH v1 0/2] mm/kdump: exclude reserved pages in dumps

2018-07-23 Thread David Hildenbrand
On 23.07.2018 13:45, Vlastimil Babka wrote: > On 07/20/2018 02:34 PM, David Hildenbrand wrote: >> Dumping tools (like makedumpfile) right now don't exclude reserved pages. >> So reserved pages might be access by dump tools although nobody except >> the owner should touch them. > > Are you sure abo

Re: [PATCH v1 0/2] mm/kdump: exclude reserved pages in dumps

2018-07-23 Thread Michal Hocko
On Mon 23-07-18 13:45:18, Vlastimil Babka wrote: > On 07/20/2018 02:34 PM, David Hildenbrand wrote: > > Dumping tools (like makedumpfile) right now don't exclude reserved pages. > > So reserved pages might be access by dump tools although nobody except > > the owner should touch them. > > Are you

Re: [PATCH v1 0/2] mm/kdump: exclude reserved pages in dumps

2018-07-23 Thread Vlastimil Babka
On 07/20/2018 02:34 PM, David Hildenbrand wrote: > Dumping tools (like makedumpfile) right now don't exclude reserved pages. > So reserved pages might be access by dump tools although nobody except > the owner should touch them. Are you sure about that? Or maybe I understand wrong. Maybe it change