On Mon 23-05-16 09:42:00, Shi, Yang wrote: > On 5/23/2016 12:31 AM, Michal Hocko wrote: > > On Fri 20-05-16 08:41:09, Shi, Yang wrote: > > > On 5/20/2016 6:16 AM, Michal Hocko wrote: > > > > On Thu 19-05-16 15:13:26, Yang Shi wrote: > > > > [...] > > > > > diff --git a/init/main.c b/init/main.c > > > > > index b3c6e36..2075faf 100644 > > > > > --- a/init/main.c > > > > > +++ b/init/main.c > > > > > @@ -606,7 +606,6 @@ asmlinkage __visible void __init start_kernel(void) > > > > > initrd_start = 0; > > > > > } > > > > > #endif > > > > > - page_ext_init(); > > > > > debug_objects_mem_init(); > > > > > kmemleak_init(); > > > > > setup_per_cpu_pageset(); > > > > > @@ -1004,6 +1003,8 @@ static noinline void __init kernel_init_freeable(void) > > > > > sched_init_smp(); > > > > > > > > > > page_alloc_init_late(); > > > > > + /* Initialize page ext after all struct pages are initializaed */ > > > > > + page_ext_init(); > > > > > > > > > > do_basic_setup(); > > > > > > > > I might be missing something but don't we have the same problem with > > > > CONFIG_FLATMEM? page_ext_init_flatmem is called way earlier. Or > > > > CONFIG_DEFERRED_STRUCT_PAGE_INIT is never enabled for CONFIG_FLATMEM? > > > > > > Yes, CONFIG_DEFERRED_STRUCT_PAGE_INIT depends on MEMORY_HOTPLUG which > > > depends on SPARSEMEM. So, this config is not valid for FLATMEM at all. > > > > Well > > config MEMORY_HOTPLUG > > bool "Allow for memory hot-add" > > depends on SPARSEMEM || X86_64_ACPI_NUMA > > depends on ARCH_ENABLE_MEMORY_HOTPLUG > > > > I wasn't really sure about X86_64_ACPI_NUMA dependency branch which > > depends on X86_64 && NUMA && ACPI && PCI and that didn't sound like > > SPARSEMEM only. If the FLATMEM shouldn't exist with > > Actually, FLATMEMT depends on !NUMA. Ahh, OK, you are right! Thanks for the clarification. -- Michal Hocko SUSE Labs -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>