On Mon, Feb 17, 2020 at 02:46:27PM +0900, kkabe@xxxxxxxxxxx wrote:
> ===========================================
> struct page * __meminit populate_section_memmap(unsigned long pfn,
> unsigned long nr_pages, int nid, struct vmem_altmap *altmap)
> {
> struct page *page, *ret;
> unsigned long memmap_size = sizeof(struct page) * PAGES_PER_SECTION;
>
> page = alloc_pages(GFP_KERNEL|__GFP_NOWARN, get_order(memmap_size));
> if (page) {
> goto got_map_page;
> }
> pr_info("%s: alloc_pages() returned 0x%p (should be 0), reverting to vmalloc(memmap_size=%lu)\n", __func__, page, memmap_size);
> BUG_ON(page != 0);
>
> ret = vmalloc(memmap_size);
> pr_info("%s: vmalloc(%lu) returned 0x%p\n", __func__, memmap_size, ret);
> if (ret) {
> goto got_map_ptr;
> }
>
> return NULL;
> got_map_page:
> ret = (struct page *)pfn_to_kaddr(page_to_pfn(page));
> pr_info("%s: allocated struct page *page=0x%p\n", __func__, page);
> got_map_ptr:
>
> pr_info("%s: returning struct page * =0x%p\n", __func__, ret);
> return ret;
> }
Could you please replace %p with %px. Wih the first, pointers are hashed so it is trickier
to get an overview of the meaning.
David could be right about ZONE_NORMAL vs ZONE_HIGHMEM.
IIUC, default_kernel_zone_for_pfn and default_zone_for_pfn seem to only deal with
(ZONE_DMA,ZONE_NORMAL] or ZONE_MOVABLE.
Although I really fail to see how this could cause the crash.
Could you also please capture /proc/zoneinfo before and after hotplugging memory?
And add this delta on top of your debugging patch?
diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index 0a54ffac8c68..2b9c821d7cf0 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -574,6 +574,7 @@ EXPORT_SYMBOL_GPL(restore_online_page_callback);
void generic_online_page(struct page *page, unsigned int order)
{
+ pr_info("generic_online_page: page: %px order: %u\n", page, order);
kernel_map_pages(page, 1 << order, 1);
__free_pages_core(page, order);
totalram_pages_add(1UL << order);
@@ -774,6 +775,8 @@ int __ref online_pages(unsigned long pfn, unsigned long nr_pages,
zone = zone_for_pfn_range(online_type, nid, pfn, nr_pages);
move_pfn_range_to_zone(zone, pfn, nr_pages, NULL);
+ pr_info("%s: pfn: %lx - %lx (zone: %s)\n", __func__, pfn, pfn + nr_pages, zone->name);
+
arg.start_pfn = pfn;
arg.nr_pages = nr_pages;
node_states_check_changes_online(nr_pages, zone, &arg);
--
Oscar Salvador
SUSE L3
