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, 4 insertions, 4 deletions

diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index 15d47d5e7951..27716e4932bc 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -1734,7 +1734,7 @@ int tcp_mmap(struct file *file, struct socket *sock,
 		return -EPERM;
 	vma->vm_flags &= ~(VM_MAYWRITE | VM_MAYEXEC);
 
-	/* Instruct vm_insert_page() to not down_read(mmap_sem) */
+	/* Instruct vm_insert_page() to not mmap_read_lock(mm) */
 	vma->vm_flags |= VM_MIXEDMAP;
 
 	vma->vm_ops = &tcp_vm_ops;
@@ -1762,11 +1762,11 @@ static int tcp_zerocopy_receive(struct sock *sk,
 
 	sock_rps_record_flow(sk);
 
-	down_read(&current->mm->mmap_sem);
+	mmap_read_lock(current->mm);
 
 	vma = find_vma(current->mm, address);
 	if (!vma || vma->vm_start > address || vma->vm_ops != &tcp_vm_ops) {
-		up_read(&current->mm->mmap_sem);
+		mmap_read_unlock(current->mm);
 		return -EINVAL;
 	}
 	zc->length = min_t(unsigned long, zc->length, vma->vm_end - address);
@@ -1827,7 +1827,7 @@ static int tcp_zerocopy_receive(struct sock *sk,
 		frags++;
 	}
 out:
-	up_read(&current->mm->mmap_sem);
+	mmap_read_unlock(current->mm);
 	if (length) {
 		WRITE_ONCE(tp->copied_seq, seq);
 		tcp_rcv_space_adjust(sk);