11 files changed, 205 insertions, 50 deletions

diff --git a/Documentation/kdump/gdbmacros.txt b/Documentation/kdump/gdbmacros.txt
index 35f6a982a0d5..220d0a80ca2c 100644
--- a/Documentation/kdump/gdbmacros.txt
+++ b/Documentation/kdump/gdbmacros.txt
@@ -170,21 +170,92 @@ document trapinfo
         address the kernel panicked.
 end
 
+define dump_log_idx
+        set $idx = $arg0
+        if ($argc > 1)
+                set $prev_flags = $arg1
+        else
+                set $prev_flags = 0
+        end
+        set $msg = ((struct printk_log *) (log_buf + $idx))
+        set $prefix = 1
+        set $newline = 1
+        set $log = log_buf + $idx + sizeof(*$msg)
 
-define dmesg
-        set $i = 0
-        set $end_idx = (log_end - 1) & (log_buf_len - 1)
+        # prev & LOG_CONT && !(msg->flags & LOG_PREIX)
+        if (($prev_flags & 8) && !($msg->flags & 4))
+                set $prefix = 0
+        end
+
+        # msg->flags & LOG_CONT
+        if ($msg->flags & 8)
+                # (prev & LOG_CONT && !(prev & LOG_NEWLINE))
+                if (($prev_flags & 8) && !($prev_flags & 2))
+                        set $prefix = 0
+                end
+                # (!(msg->flags & LOG_NEWLINE))
+                if (!($msg->flags & 2))
+                        set $newline = 0
+                end
+        end
+
+        if ($prefix)
+                printf "[%5lu.%06lu] ", $msg->ts_nsec / 1000000000, $msg->ts_nsec % 1000000000
+        end
+        if ($msg->text_len != 0)
+                eval "printf \"%%%d.%ds\", $log", $msg->text_len, $msg->text_len
+        end
+        if ($newline)
+                printf "\n"
+        end
+        if ($msg->dict_len > 0)
+                set $dict = $log + $msg->text_len
+                set $idx = 0
+                set $line = 1
+                while ($idx < $msg->dict_len)
+                        if ($line)
+                                printf " "
+                                set $line = 0
+                        end
+                        set $c = $dict[$idx]
+                        if ($c == '\0')
+                                printf "\n"
+                                set $line = 1
+                        else
+                                if ($c < ' ' || $c >= 127 || $c == '\\')
+                                        printf "\\x%02x", $c
+                                else
+                                        printf "%c", $c
+                                end
+                        end
+                        set $idx = $idx + 1
+                end
+                printf "\n"
+        end
+end
+document dump_log_idx
+        Dump a single log given its index in the log buffer.  The first
+        parameter is the index into log_buf, the second is optional and
+        specified the previous log buffer's flags, used for properly
+        formatting continued lines.
+end
 
-        while ($i < logged_chars)
-                set $idx = (log_end - 1 - logged_chars + $i) & (log_buf_len - 1)
+define dmesg
+        set $i = log_first_idx
+        set $end_idx = log_first_idx
+        set $prev_flags = 0
 
-                if ($idx + 100 <= $end_idx) || \
-                   ($end_idx <= $idx && $idx + 100 < log_buf_len)
-                        printf "%.100s", &log_buf[$idx]
-                        set $i = $i + 100
+        while (1)
+                set $msg = ((struct printk_log *) (log_buf + $i))
+                if ($msg->len == 0)
+                        set $i = 0
                 else
-                        printf "%c", log_buf[$idx]
-                        set $i = $i + 1
+                        dump_log_idx $i $prev_flags
+                        set $i = $i + $msg->len
+                        set $prev_flags = $msg->flags
+                end
+                if ($i == $end_idx)
+                        loop_break
                 end
         end
 end
diff --git a/include/linux/page_idle.h b/include/linux/page_idle.h
index bf268fa92c5b..fec40271339f 100644
--- a/include/linux/page_idle.h
+++ b/include/linux/page_idle.h
@@ -46,33 +46,62 @@ extern struct page_ext_operations page_idle_ops;
 
 static inline bool page_is_young(struct page *page)
 {
-        return test_bit(PAGE_EXT_YOUNG, &lookup_page_ext(page)->flags);
+        struct page_ext *page_ext = lookup_page_ext(page);
+
+        if (unlikely(!page_ext))
+                return false;
+
+        return test_bit(PAGE_EXT_YOUNG, &page_ext->flags);
 }
 
 static inline void set_page_young(struct page *page)
 {
-        set_bit(PAGE_EXT_YOUNG, &lookup_page_ext(page)->flags);
+        struct page_ext *page_ext = lookup_page_ext(page);
+
+        if (unlikely(!page_ext))
+                return;
+
+        set_bit(PAGE_EXT_YOUNG, &page_ext->flags);
 }
 
 static inline bool test_and_clear_page_young(struct page *page)
 {
-        return test_and_clear_bit(PAGE_EXT_YOUNG,
-                                  &lookup_page_ext(page)->flags);
+        struct page_ext *page_ext = lookup_page_ext(page);
+
+        if (unlikely(!page_ext))
+                return false;
+
+        return test_and_clear_bit(PAGE_EXT_YOUNG, &page_ext->flags);
 }
 
 static inline bool page_is_idle(struct page *page)
 {
-        return test_bit(PAGE_EXT_IDLE, &lookup_page_ext(page)->flags);
+        struct page_ext *page_ext = lookup_page_ext(page);
+
+        if (unlikely(!page_ext))
+                return false;
+
+        return test_bit(PAGE_EXT_IDLE, &page_ext->flags);
 }
 
 static inline void set_page_idle(struct page *page)
 {
-        set_bit(PAGE_EXT_IDLE, &lookup_page_ext(page)->flags);
+        struct page_ext *page_ext = lookup_page_ext(page);
+
+        if (unlikely(!page_ext))
+                return;
+
+        set_bit(PAGE_EXT_IDLE, &page_ext->flags);
 }
 
 static inline void clear_page_idle(struct page *page)
 {
-        clear_bit(PAGE_EXT_IDLE, &lookup_page_ext(page)->flags);
+        struct page_ext *page_ext = lookup_page_ext(page);
+
+        if (unlikely(!page_ext))
+                return;
+
+        clear_bit(PAGE_EXT_IDLE, &page_ext->flags);
 }
 #endif /* CONFIG_64BIT */
 
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 925b431f3f03..58c69c94402a 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -2896,6 +2896,7 @@ static void memcg_offline_kmem(struct mem_cgroup *memcg)
          * ordering is imposed by list_lru_node->lock taken by
          * memcg_drain_all_list_lrus().
          */
+        rcu_read_lock(); /* can be called from css_free w/o cgroup_mutex */
         css_for_each_descendant_pre(css, &memcg->css) {
                 child = mem_cgroup_from_css(css);
                 BUG_ON(child->kmemcg_id != kmemcg_id);
@@ -2903,6 +2904,8 @@ static void memcg_offline_kmem(struct mem_cgroup *memcg)
                 if (!memcg->use_hierarchy)
                         break;
         }
+        rcu_read_unlock();
+
         memcg_drain_all_list_lrus(kmemcg_id, parent->kmemcg_id);
 
         memcg_free_cache_id(kmemcg_id);
diff --git a/mm/oom_kill.c b/mm/oom_kill.c
index dfb1ab61fb23..acbc432d1a52 100644
--- a/mm/oom_kill.c
+++ b/mm/oom_kill.c
@@ -625,8 +625,6 @@ void try_oom_reaper(struct task_struct *tsk)
         if (atomic_read(&mm->mm_users) > 1) {
                 rcu_read_lock();
                 for_each_process(p) {
-                        bool exiting;
-
                         if (!process_shares_mm(p, mm))
                                 continue;
                         if (fatal_signal_pending(p))
@@ -636,10 +634,7 @@ void try_oom_reaper(struct task_struct *tsk)
                          * If the task is exiting make sure the whole thread group
                          * is exiting and cannot acces mm anymore.
                          */
-                        spin_lock_irq(&p->sighand->siglock);
-                        exiting = signal_group_exit(p->signal);
-                        spin_unlock_irq(&p->sighand->siglock);
-                        if (exiting)
+                        if (signal_group_exit(p->signal))
                                 continue;
 
                         /* Give up */
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index f8f3bfc435ee..6903b695ebae 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -656,6 +656,9 @@ static inline void set_page_guard(struct zone *zone, struct page *page,
                 return;
 
         page_ext = lookup_page_ext(page);
+        if (unlikely(!page_ext))
+                return;
+
         __set_bit(PAGE_EXT_DEBUG_GUARD, &page_ext->flags);
 
         INIT_LIST_HEAD(&page->lru);
@@ -673,6 +676,9 @@ static inline void clear_page_guard(struct zone *zone, struct page *page,
                 return;
 
         page_ext = lookup_page_ext(page);
+        if (unlikely(!page_ext))
+                return;
+
         __clear_bit(PAGE_EXT_DEBUG_GUARD, &page_ext->flags);
 
         set_page_private(page, 0);
@@ -2609,11 +2615,12 @@ struct page *buffered_rmqueue(struct zone *preferred_zone,
                                 page = list_last_entry(list, struct page, lru);
                         else
                                 page = list_first_entry(list, struct page, lru);
-                } while (page && check_new_pcp(page));
 
-                __dec_zone_state(zone, NR_ALLOC_BATCH);
-                list_del(&page->lru);
-                pcp->count--;
+                        __dec_zone_state(zone, NR_ALLOC_BATCH);
+                        list_del(&page->lru);
+                        pcp->count--;
+
+                } while (check_new_pcp(page));
         } else {
                 /*
                  * We most definitely don't want callers attempting to
@@ -3023,6 +3030,7 @@ reset_fair:
                 apply_fair = false;
                 fair_skipped = false;
                 reset_alloc_batches(ac->preferred_zoneref->zone);
+                z = ac->preferred_zoneref;
                 goto zonelist_scan;
         }
 
@@ -3596,6 +3604,17 @@ retry:
          */
         alloc_flags = gfp_to_alloc_flags(gfp_mask);
 
+        /*
+         * Reset the zonelist iterators if memory policies can be ignored.
+         * These allocations are high priority and system rather than user
+         * orientated.
+         */
+        if ((alloc_flags & ALLOC_NO_WATERMARKS) || !(alloc_flags & ALLOC_CPUSET)) {
+                ac->zonelist = node_zonelist(numa_node_id(), gfp_mask);
+                ac->preferred_zoneref = first_zones_zonelist(ac->zonelist,
+                                        ac->high_zoneidx, ac->nodemask);
+        }
+
         /* This is the last chance, in general, before the goto nopage. */
         page = get_page_from_freelist(gfp_mask, order,
                                 alloc_flags & ~ALLOC_NO_WATERMARKS, ac);
@@ -3604,12 +3623,6 @@ retry:
 
         /* Allocate without watermarks if the context allows */
         if (alloc_flags & ALLOC_NO_WATERMARKS) {
-                /*
-                 * Ignore mempolicies if ALLOC_NO_WATERMARKS on the grounds
-                 * the allocation is high priority and these type of
-                 * allocations are system rather than user orientated
-                 */
-                ac->zonelist = node_zonelist(numa_node_id(), gfp_mask);
                 page = get_page_from_freelist(gfp_mask, order,
                                                 ALLOC_NO_WATERMARKS, ac);
                 if (page)
@@ -3808,7 +3821,11 @@ retry_cpuset:
         /* Dirty zone balancing only done in the fast path */
         ac.spread_dirty_pages = (gfp_mask & __GFP_WRITE);
 
-        /* The preferred zone is used for statistics later */
+        /*
+         * The preferred zone is used for statistics but crucially it is
+         * also used as the starting point for the zonelist iterator. It
+         * may get reset for allocations that ignore memory policies.
+         */
         ac.preferred_zoneref = first_zones_zonelist(ac.zonelist,
                                         ac.high_zoneidx, ac.nodemask);
         if (!ac.preferred_zoneref) {
diff --git a/mm/page_owner.c b/mm/page_owner.c
index 792b56da13d8..c6cda3e36212 100644
--- a/mm/page_owner.c
+++ b/mm/page_owner.c
@@ -55,6 +55,8 @@ void __reset_page_owner(struct page *page, unsigned int order)
 
         for (i = 0; i < (1 << order); i++) {
                 page_ext = lookup_page_ext(page + i);
+                if (unlikely(!page_ext))
+                        continue;
                 __clear_bit(PAGE_EXT_OWNER, &page_ext->flags);
         }
 }
@@ -62,6 +64,7 @@ void __reset_page_owner(struct page *page, unsigned int order)
 void __set_page_owner(struct page *page, unsigned int order, gfp_t gfp_mask)
 {
         struct page_ext *page_ext = lookup_page_ext(page);
+
         struct stack_trace trace = {
                 .nr_entries = 0,
                 .max_entries = ARRAY_SIZE(page_ext->trace_entries),
@@ -69,6 +72,9 @@ void __set_page_owner(struct page *page, unsigned int order, gfp_t gfp_mask)
                 .skip = 3,
         };
 
+        if (unlikely(!page_ext))
+                return;
+
         save_stack_trace(&trace);
 
         page_ext->order = order;
@@ -82,6 +88,8 @@ void __set_page_owner(struct page *page, unsigned int order, gfp_t gfp_mask)
 void __set_page_owner_migrate_reason(struct page *page, int reason)
 {
         struct page_ext *page_ext = lookup_page_ext(page);
+        if (unlikely(!page_ext))
+                return;
 
         page_ext->last_migrate_reason = reason;
 }
@@ -89,6 +97,12 @@ void __set_page_owner_migrate_reason(struct page *page, int reason)
 gfp_t __get_page_owner_gfp(struct page *page)
 {
         struct page_ext *page_ext = lookup_page_ext(page);
+        if (unlikely(!page_ext))
+                /*
+                 * The caller just returns 0 if no valid gfp
+                 * So return 0 here too.
+                 */
+                return 0;
 
         return page_ext->gfp_mask;
 }
@@ -99,6 +113,9 @@ void __copy_page_owner(struct page *oldpage, struct page *newpage)
         struct page_ext *new_ext = lookup_page_ext(newpage);
         int i;
 
+        if (unlikely(!old_ext || !new_ext))
+                return;
+
         new_ext->order = old_ext->order;
         new_ext->gfp_mask = old_ext->gfp_mask;
         new_ext->nr_entries = old_ext->nr_entries;
@@ -193,6 +210,11 @@ void __dump_page_owner(struct page *page)
         gfp_t gfp_mask = page_ext->gfp_mask;
         int mt = gfpflags_to_migratetype(gfp_mask);
 
+        if (unlikely(!page_ext)) {
+                pr_alert("There is not page extension available.\n");
+                return;
+        }
+
         if (!test_bit(PAGE_EXT_OWNER, &page_ext->flags)) {
                 pr_alert("page_owner info is not active (free page?)\n");
                 return;
@@ -251,6 +273,8 @@ read_page_owner(struct file *file, char __user *buf, size_t count, loff_t *ppos)
                 }
 
                 page_ext = lookup_page_ext(page);
+                if (unlikely(!page_ext))
+                        continue;
 
                 /*
                  * Some pages could be missed by concurrent allocation or free,
@@ -317,6 +341,8 @@ static void init_pages_in_zone(pg_data_t *pgdat, struct zone *zone)
                                 continue;
 
                         page_ext = lookup_page_ext(page);
+                        if (unlikely(!page_ext))
+                                continue;
 
                         /* Maybe overraping zone */
                         if (test_bit(PAGE_EXT_OWNER, &page_ext->flags))
diff --git a/mm/page_poison.c b/mm/page_poison.c
index 1eae5fad2446..2e647c65916b 100644
--- a/mm/page_poison.c
+++ b/mm/page_poison.c
@@ -54,6 +54,9 @@ static inline void set_page_poison(struct page *page)
         struct page_ext *page_ext;
 
         page_ext = lookup_page_ext(page);
+        if (unlikely(!page_ext))
+                return;
+
         __set_bit(PAGE_EXT_DEBUG_POISON, &page_ext->flags);
 }
 
@@ -62,6 +65,9 @@ static inline void clear_page_poison(struct page *page)
         struct page_ext *page_ext;
 
         page_ext = lookup_page_ext(page);
+        if (unlikely(!page_ext))
+                return;
+
         __clear_bit(PAGE_EXT_DEBUG_POISON, &page_ext->flags);
 }
 
@@ -70,7 +76,7 @@ bool page_is_poisoned(struct page *page)
         struct page_ext *page_ext;
 
         page_ext = lookup_page_ext(page);
-        if (!page_ext)
+        if (unlikely(!page_ext))
                 return false;
 
         return test_bit(PAGE_EXT_DEBUG_POISON, &page_ext->flags);
diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index cf7ad1a53be0..e11475cdeb7a 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -1105,7 +1105,7 @@ EXPORT_SYMBOL_GPL(vm_unmap_aliases);
  */
 void vm_unmap_ram(const void *mem, unsigned int count)
 {
-        unsigned long size = count << PAGE_SHIFT;
+        unsigned long size = (unsigned long)count << PAGE_SHIFT;
         unsigned long addr = (unsigned long)mem;
 
         BUG_ON(!addr);
@@ -1140,7 +1140,7 @@ EXPORT_SYMBOL(vm_unmap_ram);
  */
 void *vm_map_ram(struct page **pages, unsigned int count, int node, pgprot_t prot)
 {
-        unsigned long size = count << PAGE_SHIFT;
+        unsigned long size = (unsigned long)count << PAGE_SHIFT;
         unsigned long addr;
         void *mem;
 
@@ -1574,14 +1574,15 @@ void *vmap(struct page **pages, unsigned int count,
                 unsigned long flags, pgprot_t prot)
 {
         struct vm_struct *area;
+        unsigned long size;             /* In bytes */
 
         might_sleep();
 
         if (count > totalram_pages)
                 return NULL;
 
-        area = get_vm_area_caller((count << PAGE_SHIFT), flags,
-                                        __builtin_return_address(0));
+        size = (unsigned long)count << PAGE_SHIFT;
+        area = get_vm_area_caller(size, flags, __builtin_return_address(0));
         if (!area)
                 return NULL;
 
diff --git a/mm/vmstat.c b/mm/vmstat.c
index 77e42ef388c2..cb2a67bb4158 100644
--- a/mm/vmstat.c
+++ b/mm/vmstat.c
@@ -1061,6 +1061,8 @@ static void pagetypeinfo_showmixedcount_print(struct seq_file *m,
                                 continue;
 
                         page_ext = lookup_page_ext(page);
+                        if (unlikely(!page_ext))
+                                continue;
 
                         if (!test_bit(PAGE_EXT_OWNER, &page_ext->flags))
                                 continue;
diff --git a/mm/z3fold.c b/mm/z3fold.c
index 34917d55d311..8f9e89ca1d31 100644
--- a/mm/z3fold.c
+++ b/mm/z3fold.c
@@ -412,7 +412,7 @@ static void z3fold_free(struct z3fold_pool *pool, unsigned long handle)
                 /* HEADLESS page stored */
                 bud = HEADLESS;
         } else {
-                bud = (handle - zhdr->first_num) & BUDDY_MASK;
+                bud = handle_to_buddy(handle);
 
                 switch (bud) {
                 case FIRST:
@@ -572,15 +572,19 @@ next:
                         pool->pages_nr--;
                         spin_unlock(&pool->lock);
                         return 0;
-                } else if (zhdr->first_chunks != 0 &&
-                           zhdr->last_chunks != 0 && zhdr->middle_chunks != 0) {
-                        /* Full, add to buddied list */
-                        list_add(&zhdr->buddy, &pool->buddied);
-                } else if (!test_bit(PAGE_HEADLESS, &page->private)) {
-                        z3fold_compact_page(zhdr);
-                        /* add to unbuddied list */
-                        freechunks = num_free_chunks(zhdr);
-                        list_add(&zhdr->buddy, &pool->unbuddied[freechunks]);
+                }  else if (!test_bit(PAGE_HEADLESS, &page->private)) {
+                        if (zhdr->first_chunks != 0 &&
+                            zhdr->last_chunks != 0 &&
+                            zhdr->middle_chunks != 0) {
+                                /* Full, add to buddied list */
+                                list_add(&zhdr->buddy, &pool->buddied);
+                        } else {
+                                z3fold_compact_page(zhdr);
+                                /* add to unbuddied list */
+                                freechunks = num_free_chunks(zhdr);
+                                list_add(&zhdr->buddy,
+                                         &pool->unbuddied[freechunks]);
+                        }
                 }
 
                 /* add to beginning of LRU */
diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index 6750595bd7b8..4904ced676d4 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -2454,6 +2454,7 @@ sub process {
 
 # Check for git id commit length and improperly formed commit descriptions
                 if ($in_commit_log && !$commit_log_possible_stack_dump &&
+                    $line !~ /^\s*(?:Link|Patchwork|http|BugLink):/i &&
                     ($line =~ /\bcommit\s+[0-9a-f]{5,}\b/i ||
                      ($line =~ /\b[0-9a-f]{12,40}\b/i &&
                       $line !~ /[\<\[][0-9a-f]{12,40}[\>\]]/i &&