Merge tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux

Pull module updates from Rusty Russell:
 "Main excitement here is Peter Zijlstra's lockless rbtree optimization
  to speed module address lookup.  He found some abusers of the module
  lock doing that too.

  A little bit of parameter work here too; including Dan Streetman's
  breaking up the big param mutex so writing a parameter can load
  another module (yeah, really).  Unfortunately that broke the usual
  suspects, !CONFIG_MODULES and !CONFIG_SYSFS, so those fixes were
  appended too"

* tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: (26 commits)
  modules: only use mod->param_lock if CONFIG_MODULES
  param: fix module param locks when !CONFIG_SYSFS.
  rcu: merge fix for Convert ACCESS_ONCE() to READ_ONCE() and WRITE_ONCE()
  module: add per-module param_lock
  module: make perm const
  params: suppress unused variable error, warn once just in case code changes.
  modules: clarify CONFIG_MODULE_COMPRESS help, suggest 'N'.
  kernel/module.c: avoid ifdefs for sig_enforce declaration
  kernel/workqueue.c: remove ifdefs over wq_power_efficient
  kernel/params.c: export param_ops_bool_enable_only
  kernel/params.c: generalize bool_enable_only
  kernel/module.c: use generic module param operaters for sig_enforce
  kernel/params: constify struct kernel_param_ops uses
  sysfs: tightened sysfs permission checks
  module: Rework module_addr_{min,max}
  module: Use __module_address() for module_address_lookup()
  module: Make the mod_tree stuff conditional on PERF_EVENTS || TRACING
  module: Optimize __module_address() using a latched RB-tree
  rbtree: Implement generic latch_tree
  seqlock: Introduce raw_read_seqcount_latch()
  ...

init/Kconfig

@@ -1941,26 +1941,21 @@ config MODULE_COMPRESS
 	bool "Compress modules on installation"
 	depends on MODULES
 	help
-	  This option compresses the kernel modules when 'make
-	  modules_install' is run.
 
-	  The modules will be compressed either using gzip or xz depend on the
-	  choice made in "Compression algorithm".
+	  Compresses kernel modules when 'make modules_install' is run; gzip or
+	  xz depending on "Compression algorithm" below.
 
-	  module-init-tools has support for gzip format while kmod handle gzip
-	  and xz compressed modules.
+	  module-init-tools MAY support gzip, and kmod MAY support gzip and xz.
 
-	  When a kernel module is installed from outside of the main kernel
-	  source and uses the Kbuild system for installing modules then that
-	  kernel module will also be compressed when it is installed.
+	  Out-of-tree kernel modules installed using Kbuild will also be
+	  compressed upon installation.
 
-	  This option provides little benefit when the modules are to be used inside
-	  an initrd or initramfs, it generally is more efficient to compress the whole
-	  initrd or initramfs instead.
+	  Note: for modules inside an initrd or initramfs, it's more efficient
+	  to compress the whole initrd or initramfs instead.
 
-	  This is fully compatible with signed modules while the signed module is
-	  compressed. module-init-tools or kmod handles decompression and provide to
-	  other layer the uncompressed but signed payload.
+	  Note: This is fully compatible with signed modules.
+
+	  If in doubt, say N.
 
 choice
 	prompt "Compression algorithm"
@@ -1982,6 +1977,10 @@ endchoice
 
 endif # MODULES
 
+config MODULES_TREE_LOOKUP
+	def_bool y
+	depends on PERF_EVENTS || TRACING
+
 config INIT_ALL_POSSIBLE
 	bool
 	help