Merge branch 'akpm' (patches from Andrew)

Merge more updates from Andrew Morton:

 - almost all of the rest of MM

 - kasan updates

 - lots of procfs work

 - misc things

 - lib/ updates

 - checkpatch

 - rapidio

 - ipc/shm updates

 - the start of willy's XArray conversion

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (140 commits)
  page cache: use xa_lock
  xarray: add the xa_lock to the radix_tree_root
  fscache: use appropriate radix tree accessors
  export __set_page_dirty
  unicore32: turn flush_dcache_mmap_lock into a no-op
  arm64: turn flush_dcache_mmap_lock into a no-op
  mac80211_hwsim: use DEFINE_IDA
  radix tree: use GFP_ZONEMASK bits of gfp_t for flags
  linux/const.h: refactor _BITUL and _BITULL a bit
  linux/const.h: move UL() macro to include/linux/const.h
  linux/const.h: prefix include guard of uapi/linux/const.h with _UAPI
  xen, mm: allow deferred page initialization for xen pv domains
  elf: enforce MAP_FIXED on overlaying elf segments
  fs, elf: drop MAP_FIXED usage from elf_map
  mm: introduce MAP_FIXED_NOREPLACE
  MAINTAINERS: update bouncing aacraid@adaptec.com addresses
  fs/dcache.c: add cond_resched() in shrink_dentry_list()
  include/linux/kfifo.h: fix comment
  ipc/shm.c: shm_split(): remove unneeded test for NULL shm_file_data.vm_ops
  kernel/sysctl.c: add kdoc comments to do_proc_do{u}intvec_minmax_conv_param
  ...

1 files changed, 16 insertions, 4 deletions

diff --git a/kernel/utsname.c b/kernel/utsname.c
index 913fe4336d2b..dcd6be1996fe 100644
--- a/kernel/utsname.c
+++ b/kernel/utsname.c
@@ -19,6 +19,8 @@
 #include <linux/proc_ns.h>
 #include <linux/sched/task.h>
 
+static struct kmem_cache *uts_ns_cache __ro_after_init;
+
 static struct ucounts *inc_uts_namespaces(struct user_namespace *ns)
 {
 	return inc_ucount(ns, current_euid(), UCOUNT_UTS_NAMESPACES);
@@ -33,7 +35,7 @@ static struct uts_namespace *create_uts_ns(void)
 {
 	struct uts_namespace *uts_ns;
 
-	uts_ns = kmalloc(sizeof(struct uts_namespace), GFP_KERNEL);
+	uts_ns = kmem_cache_alloc(uts_ns_cache, GFP_KERNEL);
 	if (uts_ns)
 		kref_init(&uts_ns->kref);
 	return uts_ns;
@@ -42,7 +44,7 @@ static struct uts_namespace *create_uts_ns(void)
 /*
  * Clone a new ns copying an original utsname, setting refcount to 1
  * @old_ns: namespace to clone
- * Return ERR_PTR(-ENOMEM) on error (failure to kmalloc), new ns otherwise
+ * Return ERR_PTR(-ENOMEM) on error (failure to allocate), new ns otherwise
  */
 static struct uts_namespace *clone_uts_ns(struct user_namespace *user_ns,
 					  struct uts_namespace *old_ns)
@@ -75,7 +77,7 @@ static struct uts_namespace *clone_uts_ns(struct user_namespace *user_ns,
 	return ns;
 
 fail_free:
-	kfree(ns);
+	kmem_cache_free(uts_ns_cache, ns);
 fail_dec:
 	dec_uts_namespaces(ucounts);
 fail:
@@ -113,7 +115,7 @@ void free_uts_ns(struct kref *kref)
 	dec_uts_namespaces(ns->ucounts);
 	put_user_ns(ns->user_ns);
 	ns_free_inum(&ns->ns);
-	kfree(ns);
+	kmem_cache_free(uts_ns_cache, ns);
 }
 
 static inline struct uts_namespace *to_uts_ns(struct ns_common *ns)
@@ -169,3 +171,13 @@ const struct proc_ns_operations utsns_operations = {
 	.install	= utsns_install,
 	.owner		= utsns_owner,
 };
+
+void __init uts_ns_init(void)
+{
+	uts_ns_cache = kmem_cache_create_usercopy(
+			"uts_namespace", sizeof(struct uts_namespace), 0,
+			SLAB_PANIC|SLAB_ACCOUNT,
+			offsetof(struct uts_namespace, name),
+			sizeof_field(struct uts_namespace, name),
+			NULL);
+}