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 CONFIG_DEFERRED_STRUCT_PAGE_INIT can we make that explicit please?