1 files changed, 85 insertions, 87 deletions

diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index 2b2b3ccbbfb5..b9a667d36c55 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -34,6 +34,7 @@
 #include <linux/hugetlb.h>
 #include <linux/memblock.h>
 #include <linux/compaction.h>
+#include <linux/rmap.h>
 
 #include <asm/tlbflush.h>
 
@@ -253,7 +254,7 @@ static int __meminit __add_section(int nid, unsigned long phys_start_pfn,
 	if (pfn_valid(phys_start_pfn))
 		return -EEXIST;
 
-	ret = sparse_add_one_section(NODE_DATA(nid), phys_start_pfn, altmap);
+	ret = sparse_add_one_section(nid, phys_start_pfn, altmap);
 	if (ret < 0)
 		return ret;
 
@@ -743,14 +744,13 @@ void __ref move_pfn_range_to_zone(struct zone *zone, unsigned long start_pfn,
 	int nid = pgdat->node_id;
 	unsigned long flags;
 
-	if (zone_is_empty(zone))
-		init_currently_empty_zone(zone, start_pfn, nr_pages);
-
 	clear_zone_contiguous(zone);
 
 	/* TODO Huh pgdat is irqsave while zone is not. It used to be like that before */
 	pgdat_resize_lock(pgdat, &flags);
 	zone_span_writelock(zone);
+	if (zone_is_empty(zone))
+		init_currently_empty_zone(zone, start_pfn, nr_pages);
 	resize_zone_range(zone, start_pfn, nr_pages);
 	zone_span_writeunlock(zone);
 	resize_pgdat_range(pgdat, start_pfn, nr_pages);
@@ -1078,7 +1078,7 @@ static int online_memory_block(struct memory_block *mem, void *arg)
  *
  * we are OK calling __meminit stuff here - we have CONFIG_MEMORY_HOTPLUG
  */
-int __ref add_memory_resource(int nid, struct resource *res, bool online)
+int __ref add_memory_resource(int nid, struct resource *res)
 {
 	u64 start, size;
 	bool new_node = false;
@@ -1133,7 +1133,7 @@ int __ref add_memory_resource(int nid, struct resource *res, bool online)
 	mem_hotplug_done();
 
 	/* online pages if requested */
-	if (online)
+	if (memhp_auto_online)
 		walk_memory_range(PFN_DOWN(start), PFN_UP(start + size - 1),
 				  NULL, online_memory_block);
 
@@ -1157,7 +1157,7 @@ int __ref __add_memory(int nid, u64 start, u64 size)
 	if (IS_ERR(res))
 		return PTR_ERR(res);
 
-	ret = add_memory_resource(nid, res, memhp_auto_online);
+	ret = add_memory_resource(nid, res);
 	if (ret < 0)
 		release_memory_resource(res);
 	return ret;
@@ -1226,7 +1226,7 @@ static bool is_pageblock_removable_nolock(struct page *page)
 	if (!zone_spans_pfn(zone, pfn))
 		return false;
 
-	return !has_unmovable_pages(zone, page, 0, MIGRATE_MOVABLE, true);
+	return !has_unmovable_pages(zone, page, 0, MIGRATE_MOVABLE, SKIP_HWPOISON);
 }
 
 /* Checks if this range of memory is likely to be hot-removable. */
@@ -1339,18 +1339,16 @@ static struct page *new_node_page(struct page *page, unsigned long private)
 	return new_page_nodemask(page, nid, &nmask);
 }
 
-#define NR_OFFLINE_AT_ONCE_PAGES	(256)
 static int
 do_migrate_range(unsigned long start_pfn, unsigned long end_pfn)
 {
 	unsigned long pfn;
 	struct page *page;
-	int move_pages = NR_OFFLINE_AT_ONCE_PAGES;
 	int not_managed = 0;
 	int ret = 0;
 	LIST_HEAD(source);
 
-	for (pfn = start_pfn; pfn < end_pfn && move_pages > 0; pfn++) {
+	for (pfn = start_pfn; pfn < end_pfn; pfn++) {
 		if (!pfn_valid(pfn))
 			continue;
 		page = pfn_to_page(pfn);
@@ -1362,13 +1360,27 @@ do_migrate_range(unsigned long start_pfn, unsigned long end_pfn)
 				ret = -EBUSY;
 				break;
 			}
-			if (isolate_huge_page(page, &source))
-				move_pages -= 1 << compound_order(head);
+			isolate_huge_page(page, &source);
 			continue;
 		} else if (PageTransHuge(page))
 			pfn = page_to_pfn(compound_head(page))
 				+ hpage_nr_pages(page) - 1;
 
+		/*
+		 * HWPoison pages have elevated reference counts so the migration would
+		 * fail on them. It also doesn't make any sense to migrate them in the
+		 * first place. Still try to unmap such a page in case it is still mapped
+		 * (e.g. current hwpoison implementation doesn't unmap KSM pages but keep
+		 * the unmap as the catch all safety net).
+		 */
+		if (PageHWPoison(page)) {
+			if (WARN_ON(PageLRU(page)))
+				isolate_lru_page(page);
+			if (page_mapped(page))
+				try_to_unmap(page, TTU_IGNORE_MLOCK | TTU_IGNORE_ACCESS);
+			continue;
+		}
+
 		if (!get_page_unless_zero(page))
 			continue;
 		/*
@@ -1382,16 +1394,13 @@ do_migrate_range(unsigned long start_pfn, unsigned long end_pfn)
 		if (!ret) { /* Success */
 			put_page(page);
 			list_add_tail(&page->lru, &source);
-			move_pages--;
 			if (!__PageMovable(page))
 				inc_node_page_state(page, NR_ISOLATED_ANON +
 						    page_is_file_cache(page));
 
 		} else {
-#ifdef CONFIG_DEBUG_VM
-			pr_alert("failed to isolate pfn %lx\n", pfn);
+			pr_warn("failed to isolate pfn %lx\n", pfn);
 			dump_page(page, "isolation failed");
-#endif
 			put_page(page);
 			/* Because we don't have big zone->lock. we should
 			   check this again here. */
@@ -1411,8 +1420,14 @@ do_migrate_range(unsigned long start_pfn, unsigned long end_pfn)
 		/* Allocate a new page from the nearest neighbor node */
 		ret = migrate_pages(&source, new_node_page, NULL, 0,
 					MIGRATE_SYNC, MR_MEMORY_HOTPLUG);
-		if (ret)
+		if (ret) {
+			list_for_each_entry(page, &source, lru) {
+				pr_warn("migrating pfn %lx failed ret:%d ",
+				       page_to_pfn(page), ret);
+				dump_page(page, "migration failure");
+			}
 			putback_movable_pages(&source);
+		}
 	}
 out:
 	return ret;
@@ -1553,12 +1568,7 @@ static int __ref __offline_pages(unsigned long start_pfn,
 	unsigned long valid_start, valid_end;
 	struct zone *zone;
 	struct memory_notify arg;
-
-	/* at least, alignment against pageblock is necessary */
-	if (!IS_ALIGNED(start_pfn, pageblock_nr_pages))
-		return -EINVAL;
-	if (!IS_ALIGNED(end_pfn, pageblock_nr_pages))
-		return -EINVAL;
+	char *reason;
 
 	mem_hotplug_begin();
 
@@ -1567,7 +1577,9 @@ static int __ref __offline_pages(unsigned long start_pfn,
 	if (!test_pages_in_a_zone(start_pfn, end_pfn, &valid_start,
 				  &valid_end)) {
 		mem_hotplug_done();
-		return -EINVAL;
+		ret = -EINVAL;
+		reason = "multizone range";
+		goto failed_removal;
 	}
 
 	zone = page_zone(pfn_to_page(valid_start));
@@ -1576,10 +1588,12 @@ static int __ref __offline_pages(unsigned long start_pfn,
 
 	/* set above range as isolated */
 	ret = start_isolate_page_range(start_pfn, end_pfn,
-				       MIGRATE_MOVABLE, true);
+				       MIGRATE_MOVABLE,
+				       SKIP_HWPOISON | REPORT_FAILURE);
 	if (ret) {
 		mem_hotplug_done();
-		return ret;
+		reason = "failure to isolate range";
+		goto failed_removal;
 	}
 
 	arg.start_pfn = start_pfn;
@@ -1588,37 +1602,47 @@ static int __ref __offline_pages(unsigned long start_pfn,
 
 	ret = memory_notify(MEM_GOING_OFFLINE, &arg);
 	ret = notifier_to_errno(ret);
-	if (ret)
-		goto failed_removal;
+	if (ret) {
+		reason = "notifier failure";
+		goto failed_removal_isolated;
+	}
 
-	pfn = start_pfn;
-repeat:
-	/* start memory hot removal */
-	ret = -EINTR;
-	if (signal_pending(current))
-		goto failed_removal;
+	do {
+		for (pfn = start_pfn; pfn;) {
+			if (signal_pending(current)) {
+				ret = -EINTR;
+				reason = "signal backoff";
+				goto failed_removal_isolated;
+			}
 
-	cond_resched();
-	lru_add_drain_all();
-	drain_all_pages(zone);
+			cond_resched();
+			lru_add_drain_all();
+			drain_all_pages(zone);
+
+			pfn = scan_movable_pages(pfn, end_pfn);
+			if (pfn) {
+				/*
+				 * TODO: fatal migration failures should bail
+				 * out
+				 */
+				do_migrate_range(pfn, end_pfn);
+			}
+		}
 
-	pfn = scan_movable_pages(start_pfn, end_pfn);
-	if (pfn) { /* We have movable pages */
-		ret = do_migrate_range(pfn, end_pfn);
-		goto repeat;
-	}
+		/*
+		 * Dissolve free hugepages in the memory block before doing
+		 * offlining actually in order to make hugetlbfs's object
+		 * counting consistent.
+		 */
+		ret = dissolve_free_huge_pages(start_pfn, end_pfn);
+		if (ret) {
+			reason = "failure to dissolve huge pages";
+			goto failed_removal_isolated;
+		}
+		/* check again */
+		offlined_pages = check_pages_isolated(start_pfn, end_pfn);
+	} while (offlined_pages < 0);
 
-	/*
-	 * dissolve free hugepages in the memory block before doing offlining
-	 * actually in order to make hugetlbfs's object counting consistent.
-	 */
-	ret = dissolve_free_huge_pages(start_pfn, end_pfn);
-	if (ret)
-		goto failed_removal;
-	/* check again */
-	offlined_pages = check_pages_isolated(start_pfn, end_pfn);
-	if (offlined_pages < 0)
-		goto repeat;
 	pr_info("Offlined Pages %ld\n", offlined_pages);
 	/* Ok, all of our target is isolated.
 	   We cannot do rollback at this point. */
@@ -1654,13 +1678,15 @@ repeat:
 	mem_hotplug_done();
 	return 0;
 
+failed_removal_isolated:
+	undo_isolate_page_range(start_pfn, end_pfn, MIGRATE_MOVABLE);
 failed_removal:
-	pr_debug("memory offlining [mem %#010llx-%#010llx] failed\n",
+	pr_debug("memory offlining [mem %#010llx-%#010llx] failed due to %s\n",
 		 (unsigned long long) start_pfn << PAGE_SHIFT,
-		 ((unsigned long long) end_pfn << PAGE_SHIFT) - 1);
+		 ((unsigned long long) end_pfn << PAGE_SHIFT) - 1,
+		 reason);
 	memory_notify(MEM_CANCEL_OFFLINE, &arg);
 	/* pushback to free area */
-	undo_isolate_page_range(start_pfn, end_pfn, MIGRATE_MOVABLE);
 	mem_hotplug_done();
 	return ret;
 }
@@ -1753,34 +1779,6 @@ static int check_cpu_on_node(pg_data_t *pgdat)
 	return 0;
 }
 
-static void unmap_cpu_on_node(pg_data_t *pgdat)
-{
-#ifdef CONFIG_ACPI_NUMA
-	int cpu;
-
-	for_each_possible_cpu(cpu)
-		if (cpu_to_node(cpu) == pgdat->node_id)
-			numa_clear_node(cpu);
-#endif
-}
-
-static int check_and_unmap_cpu_on_node(pg_data_t *pgdat)
-{
-	int ret;
-
-	ret = check_cpu_on_node(pgdat);
-	if (ret)
-		return ret;
-
-	/*
-	 * the node will be offlined when we come here, so we can clear
-	 * the cpu_to_node() now.
-	 */
-
-	unmap_cpu_on_node(pgdat);
-	return 0;
-}
-
 /**
  * try_offline_node
  * @nid: the node ID
@@ -1813,7 +1811,7 @@ void try_offline_node(int nid)
 		return;
 	}
 
-	if (check_and_unmap_cpu_on_node(pgdat))
+	if (check_cpu_on_node(pgdat))
 		return;
 
 	/*
@@ -1858,7 +1856,7 @@ void __ref __remove_memory(int nid, u64 start, u64 size)
 	memblock_free(start, size);
 	memblock_remove(start, size);
 
-	arch_remove_memory(start, size, NULL);
+	arch_remove_memory(nid, start, size, NULL);
 
 	try_offline_node(nid);