Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/mm/vmstat.c b/mm/vmstat.c
index 7878da7..a822204 100644
--- a/mm/vmstat.c
+++ b/mm/vmstat.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  *  linux/mm/vmstat.c
  *
@@ -227,7 +228,7 @@
 	 * 125		1024		10	16-32 GB	9
 	 */
 
-	mem = zone->managed_pages >> (27 - PAGE_SHIFT);
+	mem = zone_managed_pages(zone) >> (27 - PAGE_SHIFT);
 
 	threshold = 2 * fls(num_online_cpus()) * (1 + fls(mem));
 
@@ -1143,8 +1144,10 @@
 	"nr_slab_unreclaimable",
 	"nr_isolated_anon",
 	"nr_isolated_file",
+	"workingset_nodes",
 	"workingset_refault",
 	"workingset_activate",
+	"workingset_restore",
 	"workingset_nodereclaim",
 	"nr_anon_pages",
 	"nr_mapped",
@@ -1155,13 +1158,15 @@
 	"nr_shmem",
 	"nr_shmem_hugepages",
 	"nr_shmem_pmdmapped",
+	"nr_file_hugepages",
+	"nr_file_pmdmapped",
 	"nr_anon_transparent_hugepages",
 	"nr_unstable",
 	"nr_vmscan_write",
 	"nr_vmscan_immediate_reclaim",
 	"nr_dirtied",
 	"nr_written",
-	"", /* nr_indirectly_reclaimable */
+	"nr_kernel_misc_reclaimable",
 
 	/* enum writeback_stat_item counters */
 	"nr_dirty_threshold",
@@ -1272,13 +1277,8 @@
 #endif
 #endif /* CONFIG_MEMORY_BALLOON */
 #ifdef CONFIG_DEBUG_TLBFLUSH
-#ifdef CONFIG_SMP
 	"nr_tlb_remote_flush",
 	"nr_tlb_remote_flush_received",
-#else
-	"", /* nr_tlb_remote_flush */
-	"", /* nr_tlb_remote_flush_received */
-#endif /* CONFIG_SMP */
 	"nr_tlb_local_flush_all",
 	"nr_tlb_local_flush_one",
 #endif /* CONFIG_DEBUG_TLBFLUSH */
@@ -1383,12 +1383,29 @@
 			unsigned long freecount = 0;
 			struct free_area *area;
 			struct list_head *curr;
+			bool overflow = false;
 
 			area = &(zone->free_area[order]);
 
-			list_for_each(curr, &area->free_list[mtype])
-				freecount++;
-			seq_printf(m, "%6lu ", freecount);
+			list_for_each(curr, &area->free_list[mtype]) {
+				/*
+				 * Cap the free_list iteration because it might
+				 * be really large and we are under a spinlock
+				 * so a long time spent here could trigger a
+				 * hard lockup detector. Anyway this is a
+				 * debugging tool so knowing there is a handful
+				 * of pages of this order should be more than
+				 * sufficient.
+				 */
+				if (++freecount >= 100000) {
+					overflow = true;
+					break;
+				}
+			}
+			seq_printf(m, "%s%6lu ", overflow ? ">" : "", freecount);
+			spin_unlock_irq(&zone->lock);
+			cond_resched();
+			spin_lock_irq(&zone->lock);
 		}
 		seq_putc(m, '\n');
 	}
@@ -1567,7 +1584,7 @@
 		   high_wmark_pages(zone),
 		   zone->spanned_pages,
 		   zone->present_pages,
-		   zone->managed_pages);
+		   zone_managed_pages(zone));
 
 	seq_printf(m,
 		   "\n        protection: (%ld",
@@ -1663,6 +1680,8 @@
 	stat_items_size += sizeof(struct vm_event_state);
 #endif
 
+	BUILD_BUG_ON(stat_items_size !=
+		     ARRAY_SIZE(vmstat_text) * sizeof(unsigned long));
 	v = kmalloc(stat_items_size, GFP_KERNEL);
 	m->private = v;
 	if (!v)
@@ -1706,10 +1725,6 @@
 	unsigned long *l = arg;
 	unsigned long off = l - (unsigned long *)m->private;
 
-	/* Skip hidden vmstat items. */
-	if (*vmstat_text[off] == '\0')
-		return 0;
-
 	seq_puts(m, vmstat_text[off]);
 	seq_put_decimal_ull(m, " ", *l);
 	seq_putc(m, '\n');
@@ -1827,12 +1842,13 @@
 
 		/*
 		 * The fast way of checking if there are any vmstat diffs.
-		 * This works because the diffs are byte sized items.
 		 */
-		if (memchr_inv(p->vm_stat_diff, 0, NR_VM_ZONE_STAT_ITEMS))
+		if (memchr_inv(p->vm_stat_diff, 0, NR_VM_ZONE_STAT_ITEMS *
+			       sizeof(p->vm_stat_diff[0])))
 			return true;
 #ifdef CONFIG_NUMA
-		if (memchr_inv(p->vm_numa_stat_diff, 0, NR_VM_NUMA_STAT_ITEMS))
+		if (memchr_inv(p->vm_numa_stat_diff, 0, NR_VM_NUMA_STAT_ITEMS *
+			       sizeof(p->vm_numa_stat_diff[0])))
 			return true;
 #endif
 	}
@@ -1973,7 +1989,7 @@
 #endif
 #ifdef CONFIG_PROC_FS
 	proc_create_seq("buddyinfo", 0444, NULL, &fragmentation_op);
-	proc_create_seq("pagetypeinfo", 0444, NULL, &pagetypeinfo_op);
+	proc_create_seq("pagetypeinfo", 0400, NULL, &pagetypeinfo_op);
 	proc_create_seq("vmstat", 0444, NULL, &vmstat_op);
 	proc_create_seq("zoneinfo", 0444, NULL, &zoneinfo_op);
 #endif
@@ -2120,21 +2136,14 @@
 	struct dentry *extfrag_debug_root;
 
 	extfrag_debug_root = debugfs_create_dir("extfrag", NULL);
-	if (!extfrag_debug_root)
-		return -ENOMEM;
 
-	if (!debugfs_create_file("unusable_index", 0444,
-			extfrag_debug_root, NULL, &unusable_file_ops))
-		goto fail;
+	debugfs_create_file("unusable_index", 0444, extfrag_debug_root, NULL,
+			    &unusable_file_ops);
 
-	if (!debugfs_create_file("extfrag_index", 0444,
-			extfrag_debug_root, NULL, &extfrag_file_ops))
-		goto fail;
+	debugfs_create_file("extfrag_index", 0444, extfrag_debug_root, NULL,
+			    &extfrag_file_ops);
 
 	return 0;
-fail:
-	debugfs_remove_recursive(extfrag_debug_root);
-	return -ENOMEM;
 }
 
 module_init(extfrag_debug_init);