Merge branch 'akpm' (patches from Andrew)

Merge even more updates from Andrew Morton:

 - a kernel-wide sweep of show_stack()

 - pagetable cleanups

 - abstract out accesses to mmap_sem - prep for mmap_sem scalability work

 - hch's user acess work

Subsystems affected by this patch series: debug, mm/pagemap, mm/maccess,
mm/documentation.

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (93 commits)
  include/linux/cache.h: expand documentation over __read_mostly
  maccess: return -ERANGE when probe_kernel_read() fails
  x86: use non-set_fs based maccess routines
  maccess: allow architectures to provide kernel probing directly
  maccess: move user access routines together
  maccess: always use strict semantics for probe_kernel_read
  maccess: remove strncpy_from_unsafe
  tracing/kprobes: handle mixed kernel/userspace probes better
  bpf: rework the compat kernel probe handling
  bpf:bpf_seq_printf(): handle potentially unsafe format string better
  bpf: handle the compat string in bpf_trace_copy_string better
  bpf: factor out a bpf_trace_copy_string helper
  maccess: unify the probe kernel arch hooks
  maccess: remove probe_read_common and probe_write_common
  maccess: rename strnlen_unsafe_user to strnlen_user_nofault
  maccess: rename strncpy_from_unsafe_strict to strncpy_from_kernel_nofault
  maccess: rename strncpy_from_unsafe_user to strncpy_from_user_nofault
  maccess: update the top of file comment
  maccess: clarify kerneldoc comments
  maccess: remove duplicate kerneldoc comments
  ...

1 files changed, 5 insertions, 6 deletions

diff --git a/kernel/exit.c b/kernel/exit.c
index c300253a7b8e..727150f28103 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -66,7 +66,6 @@
 
 #include <linux/uaccess.h>
 #include <asm/unistd.h>
-#include <asm/pgtable.h>
 #include <asm/mmu_context.h>
 
 static void __unhash_process(struct task_struct *p, bool group_dead)
@@ -441,17 +440,17 @@ static void exit_mm(void)
 	sync_mm_rss(mm);
 	/*
 	 * Serialize with any possible pending coredump.
-	 * We must hold mmap_sem around checking core_state
+	 * We must hold mmap_lock around checking core_state
 	 * and clearing tsk->mm.  The core-inducing thread
 	 * will increment ->nr_threads for each thread in the
 	 * group with ->mm != NULL.
 	 */
-	down_read(&mm->mmap_sem);
+	mmap_read_lock(mm);
 	core_state = mm->core_state;
 	if (core_state) {
 		struct core_thread self;
 
-		up_read(&mm->mmap_sem);
+		mmap_read_unlock(mm);
 
 		self.task = current;
 		self.next = xchg(&core_state->dumper.next, &self);
@@ -469,14 +468,14 @@ static void exit_mm(void)
 			freezable_schedule();
 		}
 		__set_current_state(TASK_RUNNING);
-		down_read(&mm->mmap_sem);
+		mmap_read_lock(mm);
 	}
 	mmgrab(mm);
 	BUG_ON(mm != current->active_mm);
 	/* more a memory barrier than a real lock */
 	task_lock(current);
 	current->mm = NULL;
-	up_read(&mm->mmap_sem);
+	mmap_read_unlock(mm);
 	enter_lazy_tlb(mm, current);
 	task_unlock(current);
 	mm_update_next_owner(mm);