Merge branch 'akpm' (patches from Andrew Morton)

Merge a bunch of fixes from Andrew Morton.

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  fs/proc/task_mmu.c: fix buffer overflow in add_page_map()
  arch: *: Kconfig: add "kernel/Kconfig.freezer" to "arch/*/Kconfig"
  ocfs2: fix null pointer dereference in ocfs2_dir_foreach_blk_id()
  x86 get_unmapped_area(): use proper mmap base for bottom-up direction
  ocfs2: fix NULL pointer dereference in ocfs2_duplicate_clusters_by_page
  ocfs2: Revert 40bd62e to avoid regression in extended allocation
  drivers/rtc/rtc-stmp3xxx.c: provide timeout for potentially endless loop polling a HW bit
  hugetlb: fix lockdep splat caused by pmd sharing
  aoe: adjust ref of head for compound page tails
  microblaze: fix clone syscall
  mm: save soft-dirty bits on file pages
  mm: save soft-dirty bits on swapped pages
  memcg: don't initialize kmem-cache destroying work for root caches

2 files changed, 32 insertions, 20 deletions

diff --git a/drivers/block/aoe/aoecmd.c b/drivers/block/aoe/aoecmd.c
index 99cb944a002d..4d45dba7fb8f 100644
--- a/drivers/block/aoe/aoecmd.c
+++ b/drivers/block/aoe/aoecmd.c
@@ -906,16 +906,10 @@ bio_pageinc(struct bio *bio)
 	int i;
 
 	bio_for_each_segment(bv, bio, i) {
-		page = bv->bv_page;
 		/* Non-zero page count for non-head members of
-		 * compound pages is no longer allowed by the kernel,
-		 * but this has never been seen here.
+		 * compound pages is no longer allowed by the kernel.
 		 */
-		if (unlikely(PageCompound(page)))
-			if (compound_trans_head(page) != page) {
-				pr_crit("page tail used for block I/O\n");
-				BUG();
-			}
+		page = compound_trans_head(bv->bv_page);
 		atomic_inc(&page->_count);
 	}
 }
@@ -924,10 +918,13 @@ static void
 bio_pagedec(struct bio *bio)
 {
 	struct bio_vec *bv;
+	struct page *page;
 	int i;
 
-	bio_for_each_segment(bv, bio, i)
-		atomic_dec(&bv->bv_page->_count);
+	bio_for_each_segment(bv, bio, i) {
+		page = compound_trans_head(bv->bv_page);
+		atomic_dec(&page->_count);
+	}
 }
 
 static void
diff --git a/drivers/rtc/rtc-stmp3xxx.c b/drivers/rtc/rtc-stmp3xxx.c
index 767fee2ab340..26019531db15 100644
--- a/drivers/rtc/rtc-stmp3xxx.c
+++ b/drivers/rtc/rtc-stmp3xxx.c
@@ -23,6 +23,7 @@
 #include <linux/init.h>
 #include <linux/platform_device.h>
 #include <linux/interrupt.h>
+#include <linux/delay.h>
 #include <linux/rtc.h>
 #include <linux/slab.h>
 #include <linux/of_device.h>
@@ -119,24 +120,39 @@ static void stmp3xxx_wdt_register(struct platform_device *rtc_pdev)
 }
 #endif /* CONFIG_STMP3XXX_RTC_WATCHDOG */
 
-static void stmp3xxx_wait_time(struct stmp3xxx_rtc_data *rtc_data)
+static int stmp3xxx_wait_time(struct stmp3xxx_rtc_data *rtc_data)
 {
+	int timeout = 5000; /* 3ms according to i.MX28 Ref Manual */
 	/*
-	 * The datasheet doesn't say which way round the
-	 * NEW_REGS/STALE_REGS bitfields go. In fact it's 0x1=P0,
-	 * 0x2=P1, .., 0x20=P5, 0x40=ALARM, 0x80=SECONDS
+	 * The i.MX28 Applications Processor Reference Manual, Rev. 1, 2010
+	 * states:
+	 * | The order in which registers are updated is
+	 * | Persistent 0, 1, 2, 3, 4, 5, Alarm, Seconds.
+	 * | (This list is in bitfield order, from LSB to MSB, as they would
+	 * | appear in the STALE_REGS and NEW_REGS bitfields of the HW_RTC_STAT
+	 * | register. For example, the Seconds register corresponds to
+	 * | STALE_REGS or NEW_REGS containing 0x80.)
 	 */
-	while (readl(rtc_data->io + STMP3XXX_RTC_STAT) &
-			(0x80 << STMP3XXX_RTC_STAT_STALE_SHIFT))
-		cpu_relax();
+	do {
+		if (!(readl(rtc_data->io + STMP3XXX_RTC_STAT) &
+				(0x80 << STMP3XXX_RTC_STAT_STALE_SHIFT)))
+			return 0;
+		udelay(1);
+	} while (--timeout > 0);
+	return (readl(rtc_data->io + STMP3XXX_RTC_STAT) &
+		(0x80 << STMP3XXX_RTC_STAT_STALE_SHIFT)) ? -ETIME : 0;
 }
 
 /* Time read/write */
 static int stmp3xxx_rtc_gettime(struct device *dev, struct rtc_time *rtc_tm)
 {
+	int ret;
 	struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev);
 
-	stmp3xxx_wait_time(rtc_data);
+	ret = stmp3xxx_wait_time(rtc_data);
+	if (ret)
+		return ret;
+
 	rtc_time_to_tm(readl(rtc_data->io + STMP3XXX_RTC_SECONDS), rtc_tm);
 	return 0;
 }
@@ -146,8 +162,7 @@ static int stmp3xxx_rtc_set_mmss(struct device *dev, unsigned long t)
 	struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev);
 
 	writel(t, rtc_data->io + STMP3XXX_RTC_SECONDS);
-	stmp3xxx_wait_time(rtc_data);
-	return 0;
+	return stmp3xxx_wait_time(rtc_data);
 }
 
 /* interrupt(s) handler */