Re: [PATCH RFC 3/6] kexec: export PG_offline to VMCOREINFO

2018-11-15 Thread Borislav Petkov
On Thu, Nov 15, 2018 at 01:01:17PM +0100, David Hildenbrand wrote: > Just saying that "I'm not the first to do it, don't hit me with a stick" :) :-) > Indeed. And we still have without makedumpfile. I think you are aware of > this, but I'll explain it just for consistency: PG_hwpoison No, I

Re: [PATCH RFC 3/6] kexec: export PG_offline to VMCOREINFO

2018-11-15 Thread Borislav Petkov
On Thu, Nov 15, 2018 at 01:11:02PM +0100, Michal Hocko wrote: > I am not familiar with kexec to judge this particular patch but we > cannot simply define any range for these pages (same as for hwpoison > ones) because they can be almost anywhere in the available memory range. > Then there can be

Re: [PATCH RFC 3/6] kexec: export PG_offline to VMCOREINFO

2018-11-15 Thread Michal Hocko
On Thu 15-11-18 12:52:13, Borislav Petkov wrote: > On Thu, Nov 15, 2018 at 12:20:40PM +0100, David Hildenbrand wrote: > > Sorry to say, but that is the current practice without which > > makedumpfile would not be able to work at all. (exclude user pages, > > exclude page cache, exclude buddy

Re: [PATCH RFC 3/6] kexec: export PG_offline to VMCOREINFO

2018-11-15 Thread David Hildenbrand
On 15.11.18 12:52, Borislav Petkov wrote: > On Thu, Nov 15, 2018 at 12:20:40PM +0100, David Hildenbrand wrote: >> Sorry to say, but that is the current practice without which >> makedumpfile would not be able to work at all. (exclude user pages, >> exclude page cache, exclude buddy pages). Let's

Re: [PATCH RFC 3/6] kexec: export PG_offline to VMCOREINFO

2018-11-15 Thread Borislav Petkov
On Thu, Nov 15, 2018 at 12:20:40PM +0100, David Hildenbrand wrote: > Sorry to say, but that is the current practice without which > makedumpfile would not be able to work at all. (exclude user pages, > exclude page cache, exclude buddy pages). Let's not reinvent the wheel > here. This is how

Re: [PATCH RFC 3/6] kexec: export PG_offline to VMCOREINFO

2018-11-15 Thread David Hildenbrand
On 15.11.18 12:10, Borislav Petkov wrote: > On Thu, Nov 15, 2018 at 02:19:23PM +0800, Dave Young wrote: >> It would be good to copy some background info from cover letter to the >> patch description so that we can get better understanding why this is >> needed now. >> >> BTW, Lianbo is working on

Re: [PATCH RFC 3/6] kexec: export PG_offline to VMCOREINFO

2018-11-15 Thread Borislav Petkov
On Thu, Nov 15, 2018 at 02:19:23PM +0800, Dave Young wrote: > It would be good to copy some background info from cover letter to the > patch description so that we can get better understanding why this is > needed now. > > BTW, Lianbo is working on a documentation of the vmcoreinfo exported >

Re: [PATCH RFC 3/6] kexec: export PG_offline to VMCOREINFO

2018-11-15 Thread David Hildenbrand
On 15.11.18 07:19, Dave Young wrote: > Hi David, > > On 11/14/18 at 10:17pm, David Hildenbrand wrote: >> Let's export PG_offline via PAGE_OFFLINE_MAPCOUNT_VALUE, so >> makedumpfile can directly skip pages that are logically offline and the >> content therefore stale. > > It would be good to copy

Re: [PATCH RFC 3/6] kexec: export PG_offline to VMCOREINFO

2018-11-14 Thread Dave Young
Hi David, On 11/14/18 at 10:17pm, David Hildenbrand wrote: > Let's export PG_offline via PAGE_OFFLINE_MAPCOUNT_VALUE, so > makedumpfile can directly skip pages that are logically offline and the > content therefore stale. It would be good to copy some background info from cover letter to the