Merge branch 'akpm' (patches from Andrew)

Merge updates from Andrew Morton:
 "142 patches:

   - DAX updates

   - various misc bits

   - OCFS2 updates

   - most of MM"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (142 commits)
  mm/z3fold.c: limit first_num to the actual range of possible buddy indexes
  mm: fix <linux/pagemap.h> stray kernel-doc notation
  zram: remove obsolete sysfs attrs
  mm/memblock.c: remove unnecessary log and clean up
  oom-reaper: use madvise_dontneed() logic to decide if unmap the VMA
  mm: drop unused argument of zap_page_range()
  mm: drop zap_details::check_swap_entries
  mm: drop zap_details::ignore_dirty
  mm, page_alloc: warn_alloc nodemask is NULL when cpusets are disabled
  mm: help __GFP_NOFAIL allocations which do not trigger OOM killer
  mm, oom: do not enforce OOM killer for __GFP_NOFAIL automatically
  mm: consolidate GFP_NOFAIL checks in the allocator slowpath
  lib/show_mem.c: teach show_mem to work with the given nodemask
  arch, mm: remove arch specific show_mem
  mm, page_alloc: warn_alloc print nodemask
  mm, page_alloc: do not report all nodes in show_mem
  Revert "mm: bail out in shrink_inactive_list()"
  mm, vmscan: consider eligible zones in get_scan_count
  mm, vmscan: cleanup lru size claculations
  mm, vmscan: do not count freed pages as PGDEACTIVATE
  ...

3 files changed, 60 insertions, 13 deletions

diff --git a/kernel/fork.c b/kernel/fork.c
index ff82e24573b6..d12fcc4db8a3 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -55,6 +55,7 @@
 #include <linux/rmap.h>
 #include <linux/ksm.h>
 #include <linux/acct.h>
+#include <linux/userfaultfd_k.h>
 #include <linux/tsacct_kern.h>
 #include <linux/cn_proc.h>
 #include <linux/freezer.h>
@@ -561,6 +562,7 @@ static __latent_entropy int dup_mmap(struct mm_struct *mm,
 	struct rb_node **rb_link, *rb_parent;
 	int retval;
 	unsigned long charge;
+	LIST_HEAD(uf);
 
 	uprobe_start_dup_mmap();
 	if (down_write_killable(&oldmm->mmap_sem)) {
@@ -617,12 +619,13 @@ static __latent_entropy int dup_mmap(struct mm_struct *mm,
 		if (retval)
 			goto fail_nomem_policy;
 		tmp->vm_mm = mm;
+		retval = dup_userfaultfd(tmp, &uf);
+		if (retval)
+			goto fail_nomem_anon_vma_fork;
 		if (anon_vma_fork(tmp, mpnt))
 			goto fail_nomem_anon_vma_fork;
-		tmp->vm_flags &=
-			~(VM_LOCKED|VM_LOCKONFAULT|VM_UFFD_MISSING|VM_UFFD_WP);
+		tmp->vm_flags &= ~(VM_LOCKED | VM_LOCKONFAULT);
 		tmp->vm_next = tmp->vm_prev = NULL;
-		tmp->vm_userfaultfd_ctx = NULL_VM_UFFD_CTX;
 		file = tmp->vm_file;
 		if (file) {
 			struct inode *inode = file_inode(file);
@@ -678,6 +681,7 @@ out:
 	up_write(&mm->mmap_sem);
 	flush_tlb_mm(oldmm);
 	up_write(&oldmm->mmap_sem);
+	dup_userfaultfd_complete(&uf);
 fail_uprobe_end:
 	uprobe_end_dup_mmap();
 	return retval;
diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c
index aea6a1218c7d..070866c32eb9 100644
--- a/kernel/trace/trace_output.c
+++ b/kernel/trace/trace_output.c
@@ -124,6 +124,44 @@ EXPORT_SYMBOL(trace_print_symbols_seq);
 
 #if BITS_PER_LONG == 32
 const char *
+trace_print_flags_seq_u64(struct trace_seq *p, const char *delim,
+		      unsigned long long flags,
+		      const struct trace_print_flags_u64 *flag_array)
+{
+	unsigned long long mask;
+	const char *str;
+	const char *ret = trace_seq_buffer_ptr(p);
+	int i, first = 1;
+
+	for (i = 0;  flag_array[i].name && flags; i++) {
+
+		mask = flag_array[i].mask;
+		if ((flags & mask) != mask)
+			continue;
+
+		str = flag_array[i].name;
+		flags &= ~mask;
+		if (!first && delim)
+			trace_seq_puts(p, delim);
+		else
+			first = 0;
+		trace_seq_puts(p, str);
+	}
+
+	/* check for left over flags */
+	if (flags) {
+		if (!first && delim)
+			trace_seq_puts(p, delim);
+		trace_seq_printf(p, "0x%llx", flags);
+	}
+
+	trace_seq_putc(p, 0);
+
+	return ret;
+}
+EXPORT_SYMBOL(trace_print_flags_seq_u64);
+
+const char *
 trace_print_symbols_seq_u64(struct trace_seq *p, unsigned long long val,
 			 const struct trace_print_flags_u64 *symbol_array)
 {
diff --git a/kernel/watchdog_hld.c b/kernel/watchdog_hld.c
index 12b8dd640786..b5de262a9eb9 100644
--- a/kernel/watchdog_hld.c
+++ b/kernel/watchdog_hld.c
@@ -137,12 +137,14 @@ static void watchdog_overflow_callback(struct perf_event *event,
  * Reduce the watchdog noise by only printing messages
  * that are different from what cpu0 displayed.
  */
-static unsigned long cpu0_err;
+static unsigned long firstcpu_err;
+static atomic_t watchdog_cpus;
 
 int watchdog_nmi_enable(unsigned int cpu)
 {
 	struct perf_event_attr *wd_attr;
 	struct perf_event *event = per_cpu(watchdog_ev, cpu);
+	int firstcpu = 0;
 
 	/* nothing to do if the hard lockup detector is disabled */
 	if (!(watchdog_enabled & NMI_WATCHDOG_ENABLED))
@@ -156,19 +158,22 @@ int watchdog_nmi_enable(unsigned int cpu)
 	if (event != NULL)
 		goto out_enable;
 
+	if (atomic_inc_return(&watchdog_cpus) == 1)
+		firstcpu = 1;
+
 	wd_attr = &wd_hw_attr;
 	wd_attr->sample_period = hw_nmi_get_sample_period(watchdog_thresh);
 
 	/* Try to register using hardware perf events */
 	event = perf_event_create_kernel_counter(wd_attr, cpu, NULL, watchdog_overflow_callback, NULL);
 
-	/* save cpu0 error for future comparision */
-	if (cpu == 0 && IS_ERR(event))
-		cpu0_err = PTR_ERR(event);
+	/* save the first cpu's error for future comparision */
+	if (firstcpu && IS_ERR(event))
+		firstcpu_err = PTR_ERR(event);
 
 	if (!IS_ERR(event)) {
-		/* only print for cpu0 or different than cpu0 */
-		if (cpu == 0 || cpu0_err)
+		/* only print for the first cpu initialized */
+		if (firstcpu || firstcpu_err)
 			pr_info("enabled on all CPUs, permanently consumes one hw-PMU counter.\n");
 		goto out_save;
 	}
@@ -186,7 +191,7 @@ int watchdog_nmi_enable(unsigned int cpu)
 	smp_mb__after_atomic();
 
 	/* skip displaying the same error again */
-	if (cpu > 0 && (PTR_ERR(event) == cpu0_err))
+	if (!firstcpu && (PTR_ERR(event) == firstcpu_err))
 		return PTR_ERR(event);
 
 	/* vary the KERN level based on the returned errno */
@@ -222,9 +227,9 @@ void watchdog_nmi_disable(unsigned int cpu)
 
 		/* should be in cleanup, but blocks oprofile */
 		perf_event_release_kernel(event);
-	}
-	if (cpu == 0) {
+
 		/* watchdog_nmi_enable() expects this to be zero initially. */
-		cpu0_err = 0;
+		if (atomic_dec_and_test(&watchdog_cpus))
+			firstcpu_err = 0;
 	}
 }