1 files changed, 38 insertions, 15 deletions

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index ef19f22b2b7d..df959b7d6085 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -18,7 +18,6 @@
 #include <linux/mm.h>
 #include <linux/swap.h>
 #include <linux/interrupt.h>
-#include <linux/rwsem.h>
 #include <linux/pagemap.h>
 #include <linux/jiffies.h>
 #include <linux/bootmem.h>
@@ -981,21 +980,21 @@ static void __init __free_pages_boot_core(struct page *page,
 
 #if defined(CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID) || \
         defined(CONFIG_HAVE_MEMBLOCK_NODE_MAP)
-/* Only safe to use early in boot when initialisation is single-threaded */
+
 static struct mminit_pfnnid_cache early_pfnnid_cache __meminitdata;
 
 int __meminit early_pfn_to_nid(unsigned long pfn)
 {
+        static DEFINE_SPINLOCK(early_pfn_lock);
         int nid;
 
-        /* The system will behave unpredictably otherwise */
-        BUG_ON(system_state != SYSTEM_BOOTING);
-
+        spin_lock(&early_pfn_lock);
         nid = __early_pfn_to_nid(pfn, &early_pfnnid_cache);
-        if (nid >= 0)
-                return nid;
-        /* just returns 0 */
-        return 0;
+        if (nid < 0)
+                nid = 0;
+        spin_unlock(&early_pfn_lock);
+
+        return nid;
 }
 #endif
 
@@ -1060,7 +1059,15 @@ static void __init deferred_free_range(struct page *page,
                 __free_pages_boot_core(page, pfn, 0);
 }
 
-static __initdata DECLARE_RWSEM(pgdat_init_rwsem);
+/* Completion tracking for deferred_init_memmap() threads */
+static atomic_t pgdat_init_n_undone __initdata;
+static __initdata DECLARE_COMPLETION(pgdat_init_all_done_comp);
+
+static inline void __init pgdat_init_report_one_done(void)
+{
+        if (atomic_dec_and_test(&pgdat_init_n_undone))
+                complete(&pgdat_init_all_done_comp);
+}
 
 /* Initialise remaining memory on a node */
 static int __init deferred_init_memmap(void *data)
@@ -1077,7 +1084,7 @@ static int __init deferred_init_memmap(void *data)
         const struct cpumask *cpumask = cpumask_of_node(pgdat->node_id);
 
         if (first_init_pfn == ULONG_MAX) {
-                up_read(&pgdat_init_rwsem);
+                pgdat_init_report_one_done();
                 return 0;
         }
 
@@ -1177,7 +1184,8 @@ free_range:
 
         pr_info("node %d initialised, %lu pages in %ums\n", nid, nr_pages,
                                         jiffies_to_msecs(jiffies - start));
-        up_read(&pgdat_init_rwsem);
+
+        pgdat_init_report_one_done();
         return 0;
 }
 
@@ -1185,14 +1193,17 @@ void __init page_alloc_init_late(void)
 {
         int nid;
 
+        /* There will be num_node_state(N_MEMORY) threads */
+        atomic_set(&pgdat_init_n_undone, num_node_state(N_MEMORY));
         for_each_node_state(nid, N_MEMORY) {
-                down_read(&pgdat_init_rwsem);
                 kthread_run(deferred_init_memmap, NODE_DATA(nid), "pgdatinit%d", nid);
         }
 
         /* Block until all are initialised */
-        down_write(&pgdat_init_rwsem);
-        up_write(&pgdat_init_rwsem);
+        wait_for_completion(&pgdat_init_all_done_comp);
+
+        /* Reinit limits that are based on free pages after the kernel is up */
+        files_maxfiles_init();
 }
 #endif /* CONFIG_DEFERRED_STRUCT_PAGE_INIT */
 
@@ -1285,6 +1296,10 @@ static inline int check_new_page(struct page *page)
                 bad_reason = "non-NULL mapping";
         if (unlikely(atomic_read(&page->_count) != 0))
                 bad_reason = "nonzero _count";
+        if (unlikely(page->flags & __PG_HWPOISON)) {
+                bad_reason = "HWPoisoned (hardware-corrupted)";
+                bad_flags = __PG_HWPOISON;
+        }
         if (unlikely(page->flags & PAGE_FLAGS_CHECK_AT_PREP)) {
                 bad_reason = "PAGE_FLAGS_CHECK_AT_PREP flag set";
                 bad_flags = PAGE_FLAGS_CHECK_AT_PREP;
@@ -5045,6 +5060,10 @@ static unsigned long __meminit zone_spanned_pages_in_node(int nid,
 {
         unsigned long zone_start_pfn, zone_end_pfn;
 
+        /* When hotadd a new node, the node should be empty */
+        if (!node_start_pfn && !node_end_pfn)
+                return 0;
+
         /* Get the start and end of the zone */
         zone_start_pfn = arch_zone_lowest_possible_pfn[zone_type];
         zone_end_pfn = arch_zone_highest_possible_pfn[zone_type];
@@ -5108,6 +5127,10 @@ static unsigned long __meminit zone_absent_pages_in_node(int nid,
         unsigned long zone_high = arch_zone_highest_possible_pfn[zone_type];
         unsigned long zone_start_pfn, zone_end_pfn;
 
+        /* When hotadd a new node, the node should be empty */
+        if (!node_start_pfn && !node_end_pfn)
+                return 0;
+
         zone_start_pfn = clamp(node_start_pfn, zone_low, zone_high);
         zone_end_pfn = clamp(node_end_pfn, zone_low, zone_high);