Re: [PATCH v1] mm: optimize memory hotplug

2018-02-01 Thread kbuild test robot
Hi Pavel, Thank you for the patch! Yet something to improve: [auto build test ERROR on mmotm/master] [also build test ERROR on next-20180201] [cannot apply to v4.15] [if your patch is applied to the wrong git tree, please drop us a note to help improve the system] url: https://github.com/0d

Re: [PATCH v1] mm: optimize memory hotplug

2018-01-31 Thread Pavel Tatashin
Hi Michal, > So how do we check that there is no page_to_nid() user before we online > the page? The poisoning helps to catch these now, and will in the future. Because we are setting "struct page" to all 1s, we get nid that is bigger than supported, and thus panic due to NULL pointer dereference

Re: [PATCH v1] mm: optimize memory hotplug

2018-01-31 Thread Michal Hocko
On Wed 31-01-18 00:42:43, Pavel Tatashin wrote: > This patch was inspired by the discussion of this problem: > http://lkml.kernel.org/r/20180130083006.gb1...@in.ibm.com > > Currently, during memory hotplugging we traverse struct pages several > times: > > 1. memset(0) in sparse_add_one_section()