Merge branch 'akpm' (patches from Andrew)

Merge misc fixes from Andrew Morton:
 "Various fixes and followups"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  mm, compaction: make sure we isolate a valid PFN
  include/linux/generic-radix-tree.h: fix kerneldoc comment
  kernel/signal.c: trace_signal_deliver when signal_group_exit
  drivers/iommu/intel-iommu.c: fix variable 'iommu' set but not used
  spdxcheck.py: fix directory structures
  kasan: initialize tag to 0xff in __kasan_kmalloc
  z3fold: fix sheduling while atomic
  scripts/gdb: fix invocation when CONFIG_COMMON_CLK is not set
  mm/gup: continue VM_FAULT_RETRY processing even for pre-faults
  ocfs2: fix error path kobject memory leak
  memcg: make it work on sparse non-0-node systems
  mm, memcg: consider subtrees in memory.events
  prctl_set_mm: downgrade mmap_sem to read lock
  prctl_set_mm: refactor checks from validate_prctl_map
  kernel/fork.c: make max_threads symbol static
  arch/arm/boot/compressed/decompress.c: fix build error due to lz4 changes
  arch/parisc/configs/c8000_defconfig: remove obsoleted CONFIG_DEBUG_SLAB_LEAK
  mm/vmalloc.c: fix typo in comment
  lib/sort.c: fix kernel-doc notation warnings
  mm: fix Documentation/vm/hmm.rst Sphinx warnings

7 files changed, 22 insertions, 22 deletions

diff --git a/mm/compaction.c b/mm/compaction.c
index 9febc8cc84e7..9e1b9acb116b 100644
--- a/mm/compaction.c
+++ b/mm/compaction.c
@@ -1399,7 +1399,7 @@ fast_isolate_freepages(struct compact_control *cc)
 				page = pfn_to_page(highest);
 				cc->free_pfn = highest;
 			} else {
-				if (cc->direct_compaction) {
+				if (cc->direct_compaction && pfn_valid(min_pfn)) {
 					page = pfn_to_page(min_pfn);
 					cc->free_pfn = min_pfn;
 				}
diff --git a/mm/gup.c b/mm/gup.c
index f173fcbaf1b2..ddde097cf9e4 100644
--- a/mm/gup.c
+++ b/mm/gup.c
@@ -1042,10 +1042,6 @@ static __always_inline long __get_user_pages_locked(struct task_struct *tsk,
 			BUG_ON(ret >= nr_pages);
 		}
 
-		if (!pages)
-			/* If it's a prefault don't insist harder */
-			return ret;
-
 		if (ret > 0) {
 			nr_pages -= ret;
 			pages_done += ret;
@@ -1061,8 +1057,12 @@ static __always_inline long __get_user_pages_locked(struct task_struct *tsk,
 				pages_done = ret;
 			break;
 		}
-		/* VM_FAULT_RETRY triggered, so seek to the faulting offset */
-		pages += ret;
+		/*
+		 * VM_FAULT_RETRY triggered, so seek to the faulting offset.
+		 * For the prefault case (!pages) we only update counts.
+		 */
+		if (likely(pages))
+			pages += ret;
 		start += ret << PAGE_SHIFT;
 
 		/*
@@ -1085,7 +1085,8 @@ static __always_inline long __get_user_pages_locked(struct task_struct *tsk,
 		pages_done++;
 		if (!nr_pages)
 			break;
-		pages++;
+		if (likely(pages))
+			pages++;
 		start += PAGE_SIZE;
 	}
 	if (lock_dropped && *locked) {
diff --git a/mm/kasan/common.c b/mm/kasan/common.c
index 36afcf64e016..242fdc01aaa9 100644
--- a/mm/kasan/common.c
+++ b/mm/kasan/common.c
@@ -464,7 +464,7 @@ static void *__kasan_kmalloc(struct kmem_cache *cache, const void *object,
 {
 	unsigned long redzone_start;
 	unsigned long redzone_end;
-	u8 tag;
+	u8 tag = 0xff;
 
 	if (gfpflags_allow_blocking(flags))
 		quarantine_reduce();
diff --git a/mm/list_lru.c b/mm/list_lru.c
index 0bdf3152735e..e4709fdaa8e6 100644
--- a/mm/list_lru.c
+++ b/mm/list_lru.c
@@ -38,11 +38,7 @@ static int lru_shrinker_id(struct list_lru *lru)
 
 static inline bool list_lru_memcg_aware(struct list_lru *lru)
 {
-	/*
-	 * This needs node 0 to be always present, even
-	 * in the systems supporting sparse numa ids.
-	 */
-	return !!lru->node[0].memcg_lrus;
+	return lru->memcg_aware;
 }
 
 static inline struct list_lru_one *
@@ -452,6 +448,8 @@ static int memcg_init_list_lru(struct list_lru *lru, bool memcg_aware)
 {
 	int i;
 
+	lru->memcg_aware = memcg_aware;
+
 	if (!memcg_aware)
 		return 0;
 
diff --git a/mm/util.c b/mm/util.c
index 91682a2090ee..9834c4ab7d8e 100644
--- a/mm/util.c
+++ b/mm/util.c
@@ -718,12 +718,12 @@ int get_cmdline(struct task_struct *task, char *buffer, int buflen)
 	if (!mm->arg_end)
 		goto out_mm;	/* Shh! No looking before we're done */
 
-	down_read(&mm->mmap_sem);
+	spin_lock(&mm->arg_lock);
 	arg_start = mm->arg_start;
 	arg_end = mm->arg_end;
 	env_start = mm->env_start;
 	env_end = mm->env_end;
-	up_read(&mm->mmap_sem);
+	spin_unlock(&mm->arg_lock);
 
 	len = arg_end - arg_start;
 
diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index 233af6936c93..7350a124524b 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -815,7 +815,7 @@ find_vmap_lowest_match(unsigned long size,
 			}
 
 			/*
-			 * OK. We roll back and find the fist right sub-tree,
+			 * OK. We roll back and find the first right sub-tree,
 			 * that will satisfy the search criteria. It can happen
 			 * only once due to "vstart" restriction.
 			 */
diff --git a/mm/z3fold.c b/mm/z3fold.c
index 99be52c5ca45..985732c8b025 100644
--- a/mm/z3fold.c
+++ b/mm/z3fold.c
@@ -190,10 +190,11 @@ static int size_to_chunks(size_t size)
 
 static void compact_page_work(struct work_struct *w);
 
-static inline struct z3fold_buddy_slots *alloc_slots(struct z3fold_pool *pool)
+static inline struct z3fold_buddy_slots *alloc_slots(struct z3fold_pool *pool,
+							gfp_t gfp)
 {
 	struct z3fold_buddy_slots *slots = kmem_cache_alloc(pool->c_handle,
-							GFP_KERNEL);
+							    gfp);
 
 	if (slots) {
 		memset(slots->slot, 0, sizeof(slots->slot));
@@ -295,10 +296,10 @@ static void z3fold_unregister_migration(struct z3fold_pool *pool)
 
 /* Initializes the z3fold header of a newly allocated z3fold page */
 static struct z3fold_header *init_z3fold_page(struct page *page,
-					struct z3fold_pool *pool)
+					struct z3fold_pool *pool, gfp_t gfp)
 {
 	struct z3fold_header *zhdr = page_address(page);
-	struct z3fold_buddy_slots *slots = alloc_slots(pool);
+	struct z3fold_buddy_slots *slots = alloc_slots(pool, gfp);
 
 	if (!slots)
 		return NULL;
@@ -912,7 +913,7 @@ retry:
 	if (!page)
 		return -ENOMEM;
 
-	zhdr = init_z3fold_page(page, pool);
+	zhdr = init_z3fold_page(page, pool, gfp);
 	if (!zhdr) {
 		__free_page(page);
 		return -ENOMEM;