Merge branch 'akpm' (patches from Andrew Morton)

Merge fixes from Andrew Morton:
 "10 fixes"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  Josh has moved
  kexec: export free_huge_page to VMCOREINFO
  mm: fix filemap.c pagecache_get_page() kernel-doc warnings
  mm: debugfs: move rounddown_pow_of_two() out from do_fault path
  memcg: oom_notify use-after-free fix
  hwpoison: call action_result() in failure path of hwpoison_user_mappings()
  hwpoison: fix hugetlbfs/thp precheck in hwpoison_user_mappings()
  rapidio/tsi721_dma: fix failure to obtain transaction descriptor
  mm, thp: do not allow thp faults to avoid cpuset restrictions
  mm/page-writeback.c: fix divide by zero in bdi_dirty_limits()

14 files changed, 69 insertions, 36 deletions

diff --git a/.mailmap b/.mailmap
index df1baba43a64..1ad68731fb47 100644
--- a/.mailmap
+++ b/.mailmap
@@ -62,6 +62,11 @@ Jeff Garzik <jgarzik@pretzel.yyz.us>
 Jens Axboe <axboe@suse.de>
 Jens Osterkamp <Jens.Osterkamp@de.ibm.com>
 John Stultz <johnstul@us.ibm.com>
+<josh@joshtriplett.org> <josh@freedesktop.org>
+<josh@joshtriplett.org> <josh@kernel.org>
+<josh@joshtriplett.org> <josht@linux.vnet.ibm.com>
+<josh@joshtriplett.org> <josht@us.ibm.com>
+<josh@joshtriplett.org> <josht@vnet.ibm.com>
 Juha Yrjola <at solidboot.com>
 Juha Yrjola <juha.yrjola@nokia.com>
 Juha Yrjola <juha.yrjola@solidboot.com>
diff --git a/CREDITS b/CREDITS
index 28ee1514b9de..a80b66718f66 100644
--- a/CREDITS
+++ b/CREDITS
@@ -3511,10 +3511,11 @@ S: MacGregor A.C.T 2615
 S: Australia
 
 N: Josh Triplett
-E: josh@freedesktop.org
-P: 1024D/D0FE7AFB B24A 65C9 1D71 2AC2 DE87  CA26 189B 9946 D0FE 7AFB
-D: rcutorture maintainer
+E: josh@joshtriplett.org
+P: 4096R/8AFF873D 758E 5042 E397 4BA3 3A9C  1E67 0ED9 A3DF 8AFF 873D
+D: RCU and rcutorture
 D: lock annotations, finding and fixing lock bugs
+D: kernel tinification
 
 N: Winfried Trümper
 E: winni@xpilot.org
diff --git a/MAINTAINERS b/MAINTAINERS
index 86efa7e213c2..95990dd2678c 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -7424,7 +7424,7 @@ S:	Orphan
 F:	drivers/net/wireless/ray*
 
 RCUTORTURE MODULE
-M:	Josh Triplett <josh@freedesktop.org>
+M:	Josh Triplett <josh@joshtriplett.org>
 M:	"Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
 L:	linux-kernel@vger.kernel.org
 S:	Supported
diff --git a/drivers/rapidio/devices/tsi721_dma.c b/drivers/rapidio/devices/tsi721_dma.c
index 9b60b1f3261c..44341dc5b148 100644
--- a/drivers/rapidio/devices/tsi721_dma.c
+++ b/drivers/rapidio/devices/tsi721_dma.c
@@ -287,6 +287,12 @@ struct tsi721_tx_desc *tsi721_desc_get(struct tsi721_bdma_chan *bdma_chan)
 			"desc %p not ACKed\n", tx_desc);
 	}
 
+	if (ret == NULL) {
+		dev_dbg(bdma_chan->dchan.device->dev,
+			"%s: unable to obtain tx descriptor\n", __func__);
+		goto err_out;
+	}
+
 	i = bdma_chan->wr_count_next % bdma_chan->bd_num;
 	if (i == bdma_chan->bd_num - 1) {
 		i = 0;
@@ -297,7 +303,7 @@ struct tsi721_tx_desc *tsi721_desc_get(struct tsi721_bdma_chan *bdma_chan)
 	tx_desc->txd.phys = bdma_chan->bd_phys +
 				i * sizeof(struct tsi721_dma_desc);
 	tx_desc->hw_desc = &((struct tsi721_dma_desc *)bdma_chan->bd_base)[i];
-
+err_out:
 	spin_unlock_bh(&bdma_chan->lock);
 
 	return ret;
diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h
index 255cd5cc0754..a23c096b3080 100644
--- a/include/linux/hugetlb.h
+++ b/include/linux/hugetlb.h
@@ -80,6 +80,7 @@ int dequeue_hwpoisoned_huge_page(struct page *page);
 bool isolate_huge_page(struct page *page, struct list_head *list);
 void putback_active_hugepage(struct page *page);
 bool is_hugepage_active(struct page *page);
+void free_huge_page(struct page *page);
 
 #ifdef CONFIG_ARCH_WANT_HUGE_PMD_SHARE
 pte_t *huge_pmd_share(struct mm_struct *mm, unsigned long addr, pud_t *pud);
diff --git a/kernel/kexec.c b/kernel/kexec.c
index 369f41a94124..23a088fec3c0 100644
--- a/kernel/kexec.c
+++ b/kernel/kexec.c
@@ -33,6 +33,7 @@
 #include <linux/swap.h>
 #include <linux/syscore_ops.h>
 #include <linux/compiler.h>
+#include <linux/hugetlb.h>
 
 #include <asm/page.h>
 #include <asm/uaccess.h>
@@ -1619,6 +1620,7 @@ static int __init crash_save_vmcoreinfo_init(void)
 #endif
 	VMCOREINFO_NUMBER(PG_head_mask);
 	VMCOREINFO_NUMBER(PAGE_BUDDY_MAPCOUNT_VALUE);
+	VMCOREINFO_SYMBOL(free_huge_page);
 
 	arch_crash_save_vmcoreinfo();
 	update_vmcoreinfo_note();
diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c
index 7fa34f86e5ba..948a7693748e 100644
--- a/kernel/rcu/rcutorture.c
+++ b/kernel/rcu/rcutorture.c
@@ -18,7 +18,7 @@
  * Copyright (C) IBM Corporation, 2005, 2006
  *
  * Authors: Paul E. McKenney <paulmck@us.ibm.com>
- *	  Josh Triplett <josh@freedesktop.org>
+ *	  Josh Triplett <josh@joshtriplett.org>
  *
  * See also:  Documentation/RCU/torture.txt
  */
@@ -51,7 +51,7 @@
 #include <linux/torture.h>
 
 MODULE_LICENSE("GPL");
-MODULE_AUTHOR("Paul E. McKenney <paulmck@us.ibm.com> and Josh Triplett <josh@freedesktop.org>");
+MODULE_AUTHOR("Paul E. McKenney <paulmck@us.ibm.com> and Josh Triplett <josh@joshtriplett.org>");
 
 
 torture_param(int, fqs_duration, 0,
diff --git a/mm/filemap.c b/mm/filemap.c
index dafb06f70a09..900edfaf6df5 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -1031,18 +1031,21 @@ EXPORT_SYMBOL(find_lock_entry);
  * @mapping: the address_space to search
  * @offset: the page index
  * @fgp_flags: PCG flags
- * @gfp_mask: gfp mask to use if a page is to be allocated
+ * @cache_gfp_mask: gfp mask to use for the page cache data page allocation
+ * @radix_gfp_mask: gfp mask to use for radix tree node allocation
  *
  * Looks up the page cache slot at @mapping & @offset.
  *
- * PCG flags modify how the page is returned
+ * PCG flags modify how the page is returned.
  *
  * FGP_ACCESSED: the page will be marked accessed
  * FGP_LOCK: Page is return locked
  * FGP_CREAT: If page is not present then a new page is allocated using
- *		@gfp_mask and added to the page cache and the VM's LRU
- *		list. The page is returned locked and with an increased
- *		refcount. Otherwise, %NULL is returned.
+ *		@cache_gfp_mask and added to the page cache and the VM's LRU
+ *		list. If radix tree nodes are allocated during page cache
+ *		insertion then @radix_gfp_mask is used. The page is returned
+ *		locked and with an increased refcount. Otherwise, %NULL is
+ *		returned.
  *
  * If FGP_LOCK or FGP_CREAT are specified then the function may sleep even
  * if the GFP flags specified for FGP_CREAT are atomic.
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 9221c02ed9e2..7a0a73d2fcff 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -856,7 +856,7 @@ struct hstate *size_to_hstate(unsigned long size)
 	return NULL;
 }
 
-static void free_huge_page(struct page *page)
+void free_huge_page(struct page *page)
 {
 	/*
 	 * Can't pass hstate in here because it is called from the
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index a2c7bcb0e6eb..1f14a430c656 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -5415,8 +5415,12 @@ static int mem_cgroup_oom_notify_cb(struct mem_cgroup *memcg)
 {
 	struct mem_cgroup_eventfd_list *ev;
 
+	spin_lock(&memcg_oom_lock);
+
 	list_for_each_entry(ev, &memcg->oom_notify, list)
 		eventfd_signal(ev->eventfd, 1);
+
+	spin_unlock(&memcg_oom_lock);
 	return 0;
 }
 
diff --git a/mm/memory-failure.c b/mm/memory-failure.c
index 7211a73ba14d..a013bc94ebbe 100644
--- a/mm/memory-failure.c
+++ b/mm/memory-failure.c
@@ -895,7 +895,13 @@ static int hwpoison_user_mappings(struct page *p, unsigned long pfn,
 	struct page *hpage = *hpagep;
 	struct page *ppage;
 
-	if (PageReserved(p) || PageSlab(p) || !PageLRU(p))
+	/*
+	 * Here we are interested only in user-mapped pages, so skip any
+	 * other types of pages.
+	 */
+	if (PageReserved(p) || PageSlab(p))
+		return SWAP_SUCCESS;
+	if (!(PageLRU(hpage) || PageHuge(p)))
 		return SWAP_SUCCESS;
 
 	/*
@@ -905,8 +911,10 @@ static int hwpoison_user_mappings(struct page *p, unsigned long pfn,
 	if (!page_mapped(hpage))
 		return SWAP_SUCCESS;
 
-	if (PageKsm(p))
+	if (PageKsm(p)) {
+		pr_err("MCE %#lx: can't handle KSM pages.\n", pfn);
 		return SWAP_FAIL;
+	}
 
 	if (PageSwapCache(p)) {
 		printk(KERN_ERR
@@ -1229,7 +1237,7 @@ int memory_failure(unsigned long pfn, int trapno, int flags)
 	 */
 	if (hwpoison_user_mappings(p, pfn, trapno, flags, &hpage)
 	    != SWAP_SUCCESS) {
-		printk(KERN_ERR "MCE %#lx: cannot unmap page, give up\n", pfn);
+		action_result(pfn, "unmapping failed", IGNORED);
 		res = -EBUSY;
 		goto out;
 	}
diff --git a/mm/memory.c b/mm/memory.c
index 7e8d8205b610..8b44f765b645 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -2758,23 +2758,18 @@ void do_set_pte(struct vm_area_struct *vma, unsigned long address,
 	update_mmu_cache(vma, address, pte);
 }
 
-static unsigned long fault_around_bytes = 65536;
+static unsigned long fault_around_bytes = rounddown_pow_of_two(65536);
 
-/*
- * fault_around_pages() and fault_around_mask() round down fault_around_bytes
- * to nearest page order. It's what do_fault_around() expects to see.
- */
 static inline unsigned long fault_around_pages(void)
 {
-	return rounddown_pow_of_two(fault_around_bytes) / PAGE_SIZE;
+	return fault_around_bytes >> PAGE_SHIFT;
 }
 
 static inline unsigned long fault_around_mask(void)
 {
-	return ~(rounddown_pow_of_two(fault_around_bytes) - 1) & PAGE_MASK;
+	return ~(fault_around_bytes - 1) & PAGE_MASK;
 }
 
-
 #ifdef CONFIG_DEBUG_FS
 static int fault_around_bytes_get(void *data, u64 *val)
 {
@@ -2782,11 +2777,19 @@ static int fault_around_bytes_get(void *data, u64 *val)
 	return 0;
 }
 
+/*
+ * fault_around_pages() and fault_around_mask() expects fault_around_bytes
+ * rounded down to nearest page order. It's what do_fault_around() expects to
+ * see.
+ */
 static int fault_around_bytes_set(void *data, u64 val)
 {
 	if (val / PAGE_SIZE > PTRS_PER_PTE)
 		return -EINVAL;
-	fault_around_bytes = val;
+	if (val > PAGE_SIZE)
+		fault_around_bytes = rounddown_pow_of_two(val);
+	else
+		fault_around_bytes = PAGE_SIZE; /* rounddown_pow_of_two(0) is undefined */
 	return 0;
 }
 DEFINE_SIMPLE_ATTRIBUTE(fault_around_bytes_fops,
diff --git a/mm/page-writeback.c b/mm/page-writeback.c
index 518e2c3f4c75..e0c943014eb7 100644
--- a/mm/page-writeback.c
+++ b/mm/page-writeback.c
@@ -1306,9 +1306,9 @@ static inline void bdi_dirty_limits(struct backing_dev_info *bdi,
 	*bdi_thresh = bdi_dirty_limit(bdi, dirty_thresh);
 
 	if (bdi_bg_thresh)
-		*bdi_bg_thresh = div_u64((u64)*bdi_thresh *
-					 background_thresh,
-					 dirty_thresh);
+		*bdi_bg_thresh = dirty_thresh ? div_u64((u64)*bdi_thresh *
+							background_thresh,
+							dirty_thresh) : 0;
 
 	/*
 	 * In order to avoid the stacked BDI deadlock we need
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 8bcfe3ae20cb..ef44ad736ca1 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -2447,7 +2447,7 @@ static inline int
 gfp_to_alloc_flags(gfp_t gfp_mask)
 {
 	int alloc_flags = ALLOC_WMARK_MIN | ALLOC_CPUSET;
-	const gfp_t wait = gfp_mask & __GFP_WAIT;
+	const bool atomic = !(gfp_mask & (__GFP_WAIT | __GFP_NO_KSWAPD));
 
 	/* __GFP_HIGH is assumed to be the same as ALLOC_HIGH to save a branch. */
 	BUILD_BUG_ON(__GFP_HIGH != (__force gfp_t) ALLOC_HIGH);
@@ -2456,20 +2456,20 @@ gfp_to_alloc_flags(gfp_t gfp_mask)
 	 * The caller may dip into page reserves a bit more if the caller
 	 * cannot run direct reclaim, or if the caller has realtime scheduling
 	 * policy or is asking for __GFP_HIGH memory.  GFP_ATOMIC requests will
-	 * set both ALLOC_HARDER (!wait) and ALLOC_HIGH (__GFP_HIGH).
+	 * set both ALLOC_HARDER (atomic == true) and ALLOC_HIGH (__GFP_HIGH).
 	 */
 	alloc_flags |= (__force int) (gfp_mask & __GFP_HIGH);
 
-	if (!wait) {
+	if (atomic) {
 		/*
-		 * Not worth trying to allocate harder for
-		 * __GFP_NOMEMALLOC even if it can't schedule.
+		 * Not worth trying to allocate harder for __GFP_NOMEMALLOC even
+		 * if it can't schedule.
 		 */
-		if  (!(gfp_mask & __GFP_NOMEMALLOC))
+		if (!(gfp_mask & __GFP_NOMEMALLOC))
 			alloc_flags |= ALLOC_HARDER;
 		/*
-		 * Ignore cpuset if GFP_ATOMIC (!wait) rather than fail alloc.
-		 * See also cpuset_zone_allowed() comment in kernel/cpuset.c.
+		 * Ignore cpuset mems for GFP_ATOMIC rather than fail, see the
+		 * comment for __cpuset_node_allowed_softwall().
 		 */
 		alloc_flags &= ~ALLOC_CPUSET;
 	} else if (unlikely(rt_task(current)) && !in_interrupt())