Merge branch 'akpm' (Fixes from Andrew)

Merge misc fixes from Andrew Morton:
 "8 fixes"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (8 patches)
  futex: avoid wake_futex() for a PI futex_q
  watchdog: using u64 in get_sample_period()
  writeback: put unused inodes to LRU after writeback completion
  mm: vmscan: check for fatal signals iff the process was throttled
  Revert "mm: remove __GFP_NO_KSWAPD"
  proc: check vma->vm_file before dereferencing
  UAPI: strip the _UAPI prefix from header guards during header installation
  include/linux/bug.h: fix sparse warning related to BUILD_BUG_ON_INVALID

13 files changed, 83 insertions, 23 deletions

diff --git a/drivers/mtd/mtdcore.c b/drivers/mtd/mtdcore.c
index 374c46dff7dd..ec794a72975d 100644
--- a/drivers/mtd/mtdcore.c
+++ b/drivers/mtd/mtdcore.c
@@ -1077,7 +1077,8 @@ EXPORT_SYMBOL_GPL(mtd_writev);
  * until the request succeeds or until the allocation size falls below
  * the system page size. This attempts to make sure it does not adversely
  * impact system performance, so when allocating more than one page, we
- * ask the memory allocator to avoid re-trying.
+ * ask the memory allocator to avoid re-trying, swapping, writing back
+ * or performing I/O.
  *
  * Note, this function also makes sure that the allocated buffer is aligned to
  * the MTD device's min. I/O unit, i.e. the "mtd->writesize" value.
@@ -1091,7 +1092,8 @@ EXPORT_SYMBOL_GPL(mtd_writev);
  */
 void *mtd_kmalloc_up_to(const struct mtd_info *mtd, size_t *size)
 {
-        gfp_t flags = __GFP_NOWARN | __GFP_WAIT | __GFP_NORETRY;
+        gfp_t flags = __GFP_NOWARN | __GFP_WAIT |
+                       __GFP_NORETRY | __GFP_NO_KSWAPD;
         size_t min_alloc = max_t(size_t, mtd->writesize, PAGE_SIZE);
         void *kbuf;
 
diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
index 51ea267d444c..3e3422f7f0a4 100644
--- a/fs/fs-writeback.c
+++ b/fs/fs-writeback.c
@@ -228,6 +228,8 @@ static void requeue_io(struct inode *inode, struct bdi_writeback *wb)
 static void inode_sync_complete(struct inode *inode)
 {
         inode->i_state &= ~I_SYNC;
+        /* If inode is clean an unused, put it into LRU now... */
+        inode_add_lru(inode);
         /* Waiters must see I_SYNC cleared before being woken up */
         smp_mb();
         wake_up_bit(&inode->i_state, __I_SYNC);
diff --git a/fs/inode.c b/fs/inode.c
index b03c71957246..64999f144153 100644
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -408,6 +408,19 @@ static void inode_lru_list_add(struct inode *inode)
         spin_unlock(&inode->i_sb->s_inode_lru_lock);
 }
 
+/*
+ * Add inode to LRU if needed (inode is unused and clean).
+ *
+ * Needs inode->i_lock held.
+ */
+void inode_add_lru(struct inode *inode)
+{
+        if (!(inode->i_state & (I_DIRTY | I_SYNC | I_FREEING | I_WILL_FREE)) &&
+            !atomic_read(&inode->i_count) && inode->i_sb->s_flags & MS_ACTIVE)
+                inode_lru_list_add(inode);
+}
+
+
 static void inode_lru_list_del(struct inode *inode)
 {
         spin_lock(&inode->i_sb->s_inode_lru_lock);
@@ -1390,8 +1403,7 @@ static void iput_final(struct inode *inode)
 
         if (!drop && (sb->s_flags & MS_ACTIVE)) {
                 inode->i_state |= I_REFERENCED;
-                if (!(inode->i_state & (I_DIRTY|I_SYNC)))
-                        inode_lru_list_add(inode);
+                inode_add_lru(inode);
                 spin_unlock(&inode->i_lock);
                 return;
         }
diff --git a/fs/internal.h b/fs/internal.h
index 916b7cbf3e3e..2f6af7f645eb 100644
--- a/fs/internal.h
+++ b/fs/internal.h
@@ -110,6 +110,7 @@ extern int open_check_o_direct(struct file *f);
  * inode.c
  */
 extern spinlock_t inode_sb_list_lock;
+extern void inode_add_lru(struct inode *inode);
 
 /*
  * fs-writeback.c
diff --git a/fs/proc/base.c b/fs/proc/base.c
index 3c231adf8450..9e28356a959a 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -1877,8 +1877,9 @@ static struct dentry *proc_map_files_lookup(struct inode *dir,
         if (!vma)
                 goto out_no_vma;
 
-        result = proc_map_files_instantiate(dir, dentry, task,
-                        (void *)(unsigned long)vma->vm_file->f_mode);
+        if (vma->vm_file)
+                result = proc_map_files_instantiate(dir, dentry, task,
+                                (void *)(unsigned long)vma->vm_file->f_mode);
 
 out_no_vma:
         up_read(&mm->mmap_sem);
diff --git a/include/linux/bug.h b/include/linux/bug.h
index aaac4bba6f5c..b1cf40de847e 100644
--- a/include/linux/bug.h
+++ b/include/linux/bug.h
@@ -15,6 +15,7 @@ struct pt_regs;
 #define BUILD_BUG_ON_NOT_POWER_OF_2(n)
 #define BUILD_BUG_ON_ZERO(e) (0)
 #define BUILD_BUG_ON_NULL(e) ((void*)0)
+#define BUILD_BUG_ON_INVALID(e) (0)
 #define BUILD_BUG_ON(condition)
 #define BUILD_BUG() (0)
 #else /* __CHECKER__ */
diff --git a/include/linux/gfp.h b/include/linux/gfp.h
index 02c1c9710be0..d0a79678f169 100644
--- a/include/linux/gfp.h
+++ b/include/linux/gfp.h
@@ -31,6 +31,7 @@ struct vm_area_struct;
 #define ___GFP_THISNODE         0x40000u
 #define ___GFP_RECLAIMABLE      0x80000u
 #define ___GFP_NOTRACK          0x200000u
+#define ___GFP_NO_KSWAPD        0x400000u
 #define ___GFP_OTHER_NODE       0x800000u
 #define ___GFP_WRITE            0x1000000u
 
@@ -85,6 +86,7 @@ struct vm_area_struct;
 #define __GFP_RECLAIMABLE ((__force gfp_t)___GFP_RECLAIMABLE) /* Page is reclaimable */
 #define __GFP_NOTRACK   ((__force gfp_t)___GFP_NOTRACK)  /* Don't track with kmemcheck */
 
+#define __GFP_NO_KSWAPD ((__force gfp_t)___GFP_NO_KSWAPD)
 #define __GFP_OTHER_NODE ((__force gfp_t)___GFP_OTHER_NODE) /* On behalf of other node */
 #define __GFP_WRITE     ((__force gfp_t)___GFP_WRITE)   /* Allocator intends to dirty page */
 
@@ -114,7 +116,8 @@ struct vm_area_struct;
                                  __GFP_MOVABLE)
 #define GFP_IOFS        (__GFP_IO | __GFP_FS)
 #define GFP_TRANSHUGE   (GFP_HIGHUSER_MOVABLE | __GFP_COMP | \
-                         __GFP_NOMEMALLOC | __GFP_NORETRY | __GFP_NOWARN)
+                         __GFP_NOMEMALLOC | __GFP_NORETRY | __GFP_NOWARN | \
+                         __GFP_NO_KSWAPD)
 
 #ifdef CONFIG_NUMA
 #define GFP_THISNODE    (__GFP_THISNODE | __GFP_NOWARN | __GFP_NORETRY)
diff --git a/include/trace/events/gfpflags.h b/include/trace/events/gfpflags.h
index 9391706e9254..d6fd8e5b14b7 100644
--- a/include/trace/events/gfpflags.h
+++ b/include/trace/events/gfpflags.h
@@ -36,6 +36,7 @@
         {(unsigned long)__GFP_RECLAIMABLE,      "GFP_RECLAIMABLE"},     \
         {(unsigned long)__GFP_MOVABLE,          "GFP_MOVABLE"},         \
         {(unsigned long)__GFP_NOTRACK,          "GFP_NOTRACK"},         \
+        {(unsigned long)__GFP_NO_KSWAPD,        "GFP_NO_KSWAPD"},       \
         {(unsigned long)__GFP_OTHER_NODE,       "GFP_OTHER_NODE"}       \
         ) : "GFP_NOWAIT"
 
diff --git a/kernel/futex.c b/kernel/futex.c
index 20ef219bbe9b..19eb089ca003 100644
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -843,6 +843,9 @@ static void wake_futex(struct futex_q *q)
 {
         struct task_struct *p = q->task;
 
+        if (WARN(q->pi_state || q->rt_waiter, "refusing to wake PI futex\n"))
+                return;
+
         /*
          * We set q->lock_ptr = NULL _before_ we wake up the task. If
          * a non-futex wake up happens on another CPU then the task
@@ -1078,6 +1081,10 @@ retry_private:
 
         plist_for_each_entry_safe(this, next, head, list) {
                 if (match_futex (&this->key, &key1)) {
+                        if (this->pi_state || this->rt_waiter) {
+                                ret = -EINVAL;
+                                goto out_unlock;
+                        }
                         wake_futex(this);
                         if (++ret >= nr_wake)
                                 break;
@@ -1090,6 +1097,10 @@ retry_private:
                 op_ret = 0;
                 plist_for_each_entry_safe(this, next, head, list) {
                         if (match_futex (&this->key, &key2)) {
+                                if (this->pi_state || this->rt_waiter) {
+                                        ret = -EINVAL;
+                                        goto out_unlock;
+                                }
                                 wake_futex(this);
                                 if (++op_ret >= nr_wake2)
                                         break;
@@ -1098,6 +1109,7 @@ retry_private:
                 ret += op_ret;
         }
 
+out_unlock:
         double_unlock_hb(hb1, hb2);
 out_put_keys:
         put_futex_key(&key2);
@@ -1387,9 +1399,13 @@ retry_private:
                 /*
                  * FUTEX_WAIT_REQEUE_PI and FUTEX_CMP_REQUEUE_PI should always
                  * be paired with each other and no other futex ops.
+                 *
+                 * We should never be requeueing a futex_q with a pi_state,
+                 * which is awaiting a futex_unlock_pi().
                  */
                 if ((requeue_pi && !this->rt_waiter) ||
-                    (!requeue_pi && this->rt_waiter)) {
+                    (!requeue_pi && this->rt_waiter) ||
+                    this->pi_state) {
                         ret = -EINVAL;
                         break;
                 }
diff --git a/kernel/watchdog.c b/kernel/watchdog.c
index 9d4c8d5a1f53..dd4b80a9f1a9 100644
--- a/kernel/watchdog.c
+++ b/kernel/watchdog.c
@@ -116,7 +116,7 @@ static unsigned long get_timestamp(int this_cpu)
         return cpu_clock(this_cpu) >> 30LL;  /* 2^30 ~= 10^9 */
 }
 
-static unsigned long get_sample_period(void)
+static u64 get_sample_period(void)
 {
         /*
          * convert watchdog_thresh from seconds to ns
@@ -125,7 +125,7 @@ static unsigned long get_sample_period(void)
          * and hard thresholds) to increment before the
          * hardlockup detector generates a warning
          */
-        return get_softlockup_thresh() * (NSEC_PER_SEC / 5);
+        return get_softlockup_thresh() * ((u64)NSEC_PER_SEC / 5);
 }
 
 /* Commands for resetting the watchdog */
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index bcb72c6e2b2d..92871579cbee 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -2416,8 +2416,9 @@ __alloc_pages_slowpath(gfp_t gfp_mask, unsigned int order,
                 goto nopage;
 
 restart:
-        wake_all_kswapd(order, zonelist, high_zoneidx,
-                                        zone_idx(preferred_zone));
+        if (!(gfp_mask & __GFP_NO_KSWAPD))
+                wake_all_kswapd(order, zonelist, high_zoneidx,
+                                                zone_idx(preferred_zone));
 
         /*
          * OK, we're below the kswapd watermark and have kicked background
@@ -2494,7 +2495,7 @@ rebalance:
          * system then fail the allocation instead of entering direct reclaim.
          */
         if ((deferred_compaction || contended_compaction) &&
-            (gfp_mask & (__GFP_MOVABLE|__GFP_REPEAT)) == __GFP_MOVABLE)
+                                                (gfp_mask & __GFP_NO_KSWAPD))
                 goto nopage;
 
         /* Try direct reclaim and then allocating */
diff --git a/mm/vmscan.c b/mm/vmscan.c
index 48550c66f1f2..cbf84e152f04 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -2207,9 +2207,12 @@ static bool pfmemalloc_watermark_ok(pg_data_t *pgdat)
  * Throttle direct reclaimers if backing storage is backed by the network
  * and the PFMEMALLOC reserve for the preferred node is getting dangerously
  * depleted. kswapd will continue to make progress and wake the processes
- * when the low watermark is reached
+ * when the low watermark is reached.
+ *
+ * Returns true if a fatal signal was delivered during throttling. If this
+ * happens, the page allocator should not consider triggering the OOM killer.
  */
-static void throttle_direct_reclaim(gfp_t gfp_mask, struct zonelist *zonelist,
+static bool throttle_direct_reclaim(gfp_t gfp_mask, struct zonelist *zonelist,
                                         nodemask_t *nodemask)
 {
         struct zone *zone;
@@ -2224,13 +2227,20 @@ static void throttle_direct_reclaim(gfp_t gfp_mask, struct zonelist *zonelist,
          * processes to block on log_wait_commit().
          */
         if (current->flags & PF_KTHREAD)
-                return;
+                goto out;
+
+        /*
+         * If a fatal signal is pending, this process should not throttle.
+         * It should return quickly so it can exit and free its memory
+         */
+        if (fatal_signal_pending(current))
+                goto out;
 
         /* Check if the pfmemalloc reserves are ok */
         first_zones_zonelist(zonelist, high_zoneidx, NULL, &zone);
         pgdat = zone->zone_pgdat;
         if (pfmemalloc_watermark_ok(pgdat))
-                return;
+                goto out;
 
         /* Account for the throttling */
         count_vm_event(PGSCAN_DIRECT_THROTTLE);
@@ -2246,12 +2256,20 @@ static void throttle_direct_reclaim(gfp_t gfp_mask, struct zonelist *zonelist,
         if (!(gfp_mask & __GFP_FS)) {
                 wait_event_interruptible_timeout(pgdat->pfmemalloc_wait,
                         pfmemalloc_watermark_ok(pgdat), HZ);
-                return;
+
+                goto check_pending;
         }
 
         /* Throttle until kswapd wakes the process */
         wait_event_killable(zone->zone_pgdat->pfmemalloc_wait,
                 pfmemalloc_watermark_ok(pgdat));
+
+check_pending:
+        if (fatal_signal_pending(current))
+                return true;
+
+out:
+        return false;
 }
 
 unsigned long try_to_free_pages(struct zonelist *zonelist, int order,
@@ -2273,13 +2291,12 @@ unsigned long try_to_free_pages(struct zonelist *zonelist, int order,
                 .gfp_mask = sc.gfp_mask,
         };
 
-        throttle_direct_reclaim(gfp_mask, zonelist, nodemask);
-
         /*
-         * Do not enter reclaim if fatal signal is pending. 1 is returned so
-         * that the page allocator does not consider triggering OOM
+         * Do not enter reclaim if fatal signal was delivered while throttled.
+         * 1 is returned so that the page allocator does not OOM kill at this
+         * point.
          */
-        if (fatal_signal_pending(current))
+        if (throttle_direct_reclaim(gfp_mask, zonelist, nodemask))
                 return 1;
 
         trace_mm_vmscan_direct_reclaim_begin(order,
diff --git a/scripts/headers_install.pl b/scripts/headers_install.pl
index 239d22d4207b..6c353ae8a451 100644
--- a/scripts/headers_install.pl
+++ b/scripts/headers_install.pl
@@ -42,6 +42,9 @@ foreach my $filename (@files) {
                 $line =~ s/(^|\s)(inline)\b/$1__$2__/g;
                 $line =~ s/(^|\s)(asm)\b(\s|[(]|$)/$1__$2__$3/g;
                 $line =~ s/(^|\s|[(])(volatile)\b(\s|[(]|$)/$1__$2__$3/g;
+                $line =~ s/#ifndef _UAPI/#ifndef /;
+                $line =~ s/#define _UAPI/#define /;
+                $line =~ s!#endif /[*] _UAPI!#endif /* !;
                 printf {$out} "%s", $line;
         }
         close $out;