Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/livepatching

Pull livepatching updates from Jiri Kosina:

 - RO/NX attribute fixes for patch module relocations from Josh
   Poimboeuf.  As part of this effort, module.c has been cleaned up as
   well and livepatching is piggy-backing on this cleanup.  Rusty is OK
   with this whole lot going through livepatching tree.

 - symbol disambiguation support from Chris J Arges.  That series is
   also

        Reviewed-by: Miroslav Benes <mbenes@suse.cz>

   but this came in only after I've alredy pushed out.  Didn't want to
   rebase because of that, hence I am mentioning it here.

 - symbol lookup fix from Miroslav Benes

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/livepatching:
  livepatch: Cleanup module page permission changes
  module: keep percpu symbols in module's symtab
  module: clean up RO/NX handling.
  module: use a structure to encapsulate layout.
  gcov: use within_module() helper.
  module: Use the same logic for setting and unsetting RO/NX
  livepatch: function,sympos scheme in livepatch sysfs directory
  livepatch: add sympos as disambiguator field to klp_reloc
  livepatch: add old_sympos as disambiguator field to klp_func

4 files changed, 234 insertions, 302 deletions

diff --git a/kernel/debug/kdb/kdb_main.c b/kernel/debug/kdb/kdb_main.c
index 4121345498e0..2a20c0dfdafc 100644
--- a/kernel/debug/kdb/kdb_main.c
+++ b/kernel/debug/kdb/kdb_main.c
@@ -2021,7 +2021,7 @@ static int kdb_lsmod(int argc, const char **argv)
 			continue;
 
 		kdb_printf("%-20s%8u  0x%p ", mod->name,
-			   mod->core_size, (void *)mod);
+			   mod->core_layout.size, (void *)mod);
 #ifdef CONFIG_MODULE_UNLOAD
 		kdb_printf("%4d ", module_refcount(mod));
 #endif
@@ -2031,7 +2031,7 @@ static int kdb_lsmod(int argc, const char **argv)
 			kdb_printf(" (Loading)");
 		else
 			kdb_printf(" (Live)");
-		kdb_printf(" 0x%p", mod->module_core);
+		kdb_printf(" 0x%p", mod->core_layout.base);
 
 #ifdef CONFIG_MODULE_UNLOAD
 		{
diff --git a/kernel/gcov/base.c b/kernel/gcov/base.c
index 7080ae1eb6c1..2f9df37940a0 100644
--- a/kernel/gcov/base.c
+++ b/kernel/gcov/base.c
@@ -123,11 +123,6 @@ void gcov_enable_events(void)
 }
 
 #ifdef CONFIG_MODULES
-static inline int within(void *addr, void *start, unsigned long size)
-{
-	return ((addr >= start) && (addr < start + size));
-}
-
 /* Update list and generate events when modules are unloaded. */
 static int gcov_module_notifier(struct notifier_block *nb, unsigned long event,
 				void *data)
@@ -142,7 +137,7 @@ static int gcov_module_notifier(struct notifier_block *nb, unsigned long event,
 
 	/* Remove entries located in module from linked list. */
 	while ((info = gcov_info_next(info))) {
-		if (within(info, mod->module_core, mod->core_size)) {
+		if (within_module((unsigned long)info, mod)) {
 			gcov_info_unlink(prev, info);
 			if (gcov_events_enabled)
 				gcov_event(GCOV_REMOVE, info);
diff --git a/kernel/livepatch/core.c b/kernel/livepatch/core.c
index db545cbcdb89..bc2c85c064c1 100644
--- a/kernel/livepatch/core.c
+++ b/kernel/livepatch/core.c
@@ -28,6 +28,7 @@
 #include <linux/list.h>
 #include <linux/kallsyms.h>
 #include <linux/livepatch.h>
+#include <asm/cacheflush.h>
 
 /**
  * struct klp_ops - structure for tracking registered ftrace ops structs
@@ -135,13 +136,8 @@ struct klp_find_arg {
 	const char *objname;
 	const char *name;
 	unsigned long addr;
-	/*
-	 * If count == 0, the symbol was not found. If count == 1, a unique
-	 * match was found and addr is set.  If count > 1, there is
-	 * unresolvable ambiguity among "count" number of symbols with the same
-	 * name in the same object.
-	 */
 	unsigned long count;
+	unsigned long pos;
 };
 
 static int klp_find_callback(void *data, const char *name,
@@ -158,37 +154,48 @@ static int klp_find_callback(void *data, const char *name,
 	if (args->objname && strcmp(args->objname, mod->name))
 		return 0;
 
-	/*
-	 * args->addr might be overwritten if another match is found
-	 * but klp_find_object_symbol() handles this and only returns the
-	 * addr if count == 1.
-	 */
 	args->addr = addr;
 	args->count++;
 
+	/*
+	 * Finish the search when the symbol is found for the desired position
+	 * or the position is not defined for a non-unique symbol.
+	 */
+	if ((args->pos && (args->count == args->pos)) ||
+	    (!args->pos && (args->count > 1)))
+		return 1;
+
 	return 0;
 }
 
 static int klp_find_object_symbol(const char *objname, const char *name,
-				  unsigned long *addr)
+				  unsigned long sympos, unsigned long *addr)
 {
 	struct klp_find_arg args = {
 		.objname = objname,
 		.name = name,
 		.addr = 0,
-		.count = 0
+		.count = 0,
+		.pos = sympos,
 	};
 
 	mutex_lock(&module_mutex);
 	kallsyms_on_each_symbol(klp_find_callback, &args);
 	mutex_unlock(&module_mutex);
 
-	if (args.count == 0)
+	/*
+	 * Ensure an address was found. If sympos is 0, ensure symbol is unique;
+	 * otherwise ensure the symbol position count matches sympos.
+	 */
+	if (args.addr == 0)
 		pr_err("symbol '%s' not found in symbol table\n", name);
-	else if (args.count > 1)
+	else if (args.count > 1 && sympos == 0) {
 		pr_err("unresolvable ambiguity (%lu matches) on symbol '%s' in object '%s'\n",
 		       args.count, name, objname);
-	else {
+	} else if (sympos != args.count && sympos > 0) {
+		pr_err("symbol position %lu for symbol '%s' in object '%s' not found\n",
+		       sympos, name, objname ? objname : "vmlinux");
+	} else {
 		*addr = args.addr;
 		return 0;
 	}
@@ -197,66 +204,6 @@ static int klp_find_object_symbol(const char *objname, const char *name,
 	return -EINVAL;
 }
 
-struct klp_verify_args {
-	const char *name;
-	const unsigned long addr;
-};
-
-static int klp_verify_callback(void *data, const char *name,
-			       struct module *mod, unsigned long addr)
-{
-	struct klp_verify_args *args = data;
-
-	if (!mod &&
-	    !strcmp(args->name, name) &&
-	    args->addr == addr)
-		return 1;
-
-	return 0;
-}
-
-static int klp_verify_vmlinux_symbol(const char *name, unsigned long addr)
-{
-	struct klp_verify_args args = {
-		.name = name,
-		.addr = addr,
-	};
-	int ret;
-
-	mutex_lock(&module_mutex);
-	ret = kallsyms_on_each_symbol(klp_verify_callback, &args);
-	mutex_unlock(&module_mutex);
-
-	if (!ret) {
-		pr_err("symbol '%s' not found at specified address 0x%016lx, kernel mismatch?\n",
-			name, addr);
-		return -EINVAL;
-	}
-
-	return 0;
-}
-
-static int klp_find_verify_func_addr(struct klp_object *obj,
-				     struct klp_func *func)
-{
-	int ret;
-
-#if defined(CONFIG_RANDOMIZE_BASE)
-	/* If KASLR has been enabled, adjust old_addr accordingly */
-	if (kaslr_enabled() && func->old_addr)
-		func->old_addr += kaslr_offset();
-#endif
-
-	if (!func->old_addr || klp_is_module(obj))
-		ret = klp_find_object_symbol(obj->name, func->old_name,
-					     &func->old_addr);
-	else
-		ret = klp_verify_vmlinux_symbol(func->old_name,
-						func->old_addr);
-
-	return ret;
-}
-
 /*
  * external symbols are located outside the parent object (where the parent
  * object is either vmlinux or the kmod being patched).
@@ -276,14 +223,18 @@ static int klp_find_external_symbol(struct module *pmod, const char *name,
 	}
 	preempt_enable();
 
-	/* otherwise check if it's in another .o within the patch module */
-	return klp_find_object_symbol(pmod->name, name, addr);
+	/*
+	 * Check if it's in another .o within the patch module. This also
+	 * checks that the external symbol is unique.
+	 */
+	return klp_find_object_symbol(pmod->name, name, 0, addr);
 }
 
 static int klp_write_object_relocations(struct module *pmod,
 					struct klp_object *obj)
 {
-	int ret;
+	int ret = 0;
+	unsigned long val;
 	struct klp_reloc *reloc;
 
 	if (WARN_ON(!klp_is_object_loaded(obj)))
@@ -292,41 +243,38 @@ static int klp_write_object_relocations(struct module *pmod,
 	if (WARN_ON(!obj->relocs))
 		return -EINVAL;
 
+	module_disable_ro(pmod);
+
 	for (reloc = obj->relocs; reloc->name; reloc++) {
-		if (!klp_is_module(obj)) {
-
-#if defined(CONFIG_RANDOMIZE_BASE)
-			/* If KASLR has been enabled, adjust old value accordingly */
-			if (kaslr_enabled())
-				reloc->val += kaslr_offset();
-#endif
-			ret = klp_verify_vmlinux_symbol(reloc->name,
-							reloc->val);
-			if (ret)
-				return ret;
-		} else {
-			/* module, reloc->val needs to be discovered */
-			if (reloc->external)
-				ret = klp_find_external_symbol(pmod,
-							       reloc->name,
-							       &reloc->val);
-			else
-				ret = klp_find_object_symbol(obj->mod->name,
-							     reloc->name,
-							     &reloc->val);
-			if (ret)
-				return ret;
-		}
+		/* discover the address of the referenced symbol */
+		if (reloc->external) {
+			if (reloc->sympos > 0) {
+				pr_err("non-zero sympos for external reloc symbol '%s' is not supported\n",
+				       reloc->name);
+				ret = -EINVAL;
+				goto out;
+			}
+			ret = klp_find_external_symbol(pmod, reloc->name, &val);
+		} else
+			ret = klp_find_object_symbol(obj->name,
+						     reloc->name,
+						     reloc->sympos,
+						     &val);
+		if (ret)
+			goto out;
+
 		ret = klp_write_module_reloc(pmod, reloc->type, reloc->loc,
-					     reloc->val + reloc->addend);
+					     val + reloc->addend);
 		if (ret) {
 			pr_err("relocation failed for symbol '%s' at 0x%016lx (%d)\n",
-			       reloc->name, reloc->val, ret);
-			return ret;
+			       reloc->name, val, ret);
+			goto out;
 		}
 	}
 
-	return 0;
+out:
+	module_enable_ro(pmod);
+	return ret;
 }
 
 static void notrace klp_ftrace_handler(unsigned long ip,
@@ -593,7 +541,7 @@ EXPORT_SYMBOL_GPL(klp_enable_patch);
  * /sys/kernel/livepatch/<patch>
  * /sys/kernel/livepatch/<patch>/enabled
  * /sys/kernel/livepatch/<patch>/<object>
- * /sys/kernel/livepatch/<patch>/<object>/<func>
+ * /sys/kernel/livepatch/<patch>/<object>/<function,sympos>
  */
 
 static ssize_t enabled_store(struct kobject *kobj, struct kobj_attribute *attr,
@@ -738,8 +686,14 @@ static int klp_init_func(struct klp_object *obj, struct klp_func *func)
 	INIT_LIST_HEAD(&func->stack_node);
 	func->state = KLP_DISABLED;
 
+	/* The format for the sysfs directory is <function,sympos> where sympos
+	 * is the nth occurrence of this symbol in kallsyms for the patched
+	 * object. If the user selects 0 for old_sympos, then 1 will be used
+	 * since a unique symbol will be the first occurrence.
+	 */
 	return kobject_init_and_add(&func->kobj, &klp_ktype_func,
-				    &obj->kobj, "%s", func->old_name);
+				    &obj->kobj, "%s,%lu", func->old_name,
+				    func->old_sympos ? func->old_sympos : 1);
 }
 
 /* parts of the initialization that is done only when the object is loaded */
@@ -756,7 +710,9 @@ static int klp_init_object_loaded(struct klp_patch *patch,
 	}
 
 	klp_for_each_func(obj, func) {
-		ret = klp_find_verify_func_addr(obj, func);
+		ret = klp_find_object_symbol(obj->name, func->old_name,
+					     func->old_sympos,
+					     &func->old_addr);
 		if (ret)
 			return ret;
 	}
diff --git a/kernel/module.c b/kernel/module.c
index 38c7bd5583ff..8358f4697c0c 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -80,15 +80,6 @@
 # define debug_align(X) (X)
 #endif
 
-/*
- * Given BASE and SIZE this macro calculates the number of pages the
- * memory regions occupies
- */
-#define MOD_NUMBER_OF_PAGES(BASE, SIZE) (((SIZE) > 0) ?		\
-		(PFN_DOWN((unsigned long)(BASE) + (SIZE) - 1) -	\
-			 PFN_DOWN((unsigned long)BASE) + 1)	\
-		: (0UL))
-
 /* If this is set, the section belongs in the init part of the module */
 #define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG-1))
 
@@ -108,13 +99,6 @@ static LIST_HEAD(modules);
  * Use a latched RB-tree for __module_address(); this allows us to use
  * RCU-sched lookups of the address from any context.
  *
- * Because modules have two address ranges: init and core, we need two
- * latch_tree_nodes entries. Therefore we need the back-pointer from
- * mod_tree_node.
- *
- * Because init ranges are short lived we mark them unlikely and have placed
- * them outside the critical cacheline in struct module.
- *
  * This is conditional on PERF_EVENTS || TRACING because those can really hit
  * __module_address() hard by doing a lot of stack unwinding; potentially from
  * NMI context.
@@ -122,24 +106,16 @@ static LIST_HEAD(modules);
 
 static __always_inline unsigned long __mod_tree_val(struct latch_tree_node *n)
 {
-	struct mod_tree_node *mtn = container_of(n, struct mod_tree_node, node);
-	struct module *mod = mtn->mod;
+	struct module_layout *layout = container_of(n, struct module_layout, mtn.node);
 
-	if (unlikely(mtn == &mod->mtn_init))
-		return (unsigned long)mod->module_init;
-
-	return (unsigned long)mod->module_core;
+	return (unsigned long)layout->base;
 }
 
 static __always_inline unsigned long __mod_tree_size(struct latch_tree_node *n)
 {
-	struct mod_tree_node *mtn = container_of(n, struct mod_tree_node, node);
-	struct module *mod = mtn->mod;
-
-	if (unlikely(mtn == &mod->mtn_init))
-		return (unsigned long)mod->init_size;
+	struct module_layout *layout = container_of(n, struct module_layout, mtn.node);
 
-	return (unsigned long)mod->core_size;
+	return (unsigned long)layout->size;
 }
 
 static __always_inline bool
@@ -197,23 +173,23 @@ static void __mod_tree_remove(struct mod_tree_node *node)
  */
 static void mod_tree_insert(struct module *mod)
 {
-	mod->mtn_core.mod = mod;
-	mod->mtn_init.mod = mod;
+	mod->core_layout.mtn.mod = mod;
+	mod->init_layout.mtn.mod = mod;
 
-	__mod_tree_insert(&mod->mtn_core);
-	if (mod->init_size)
-		__mod_tree_insert(&mod->mtn_init);
+	__mod_tree_insert(&mod->core_layout.mtn);
+	if (mod->init_layout.size)
+		__mod_tree_insert(&mod->init_layout.mtn);
 }
 
 static void mod_tree_remove_init(struct module *mod)
 {
-	if (mod->init_size)
-		__mod_tree_remove(&mod->mtn_init);
+	if (mod->init_layout.size)
+		__mod_tree_remove(&mod->init_layout.mtn);
 }
 
 static void mod_tree_remove(struct module *mod)
 {
-	__mod_tree_remove(&mod->mtn_core);
+	__mod_tree_remove(&mod->core_layout.mtn);
 	mod_tree_remove_init(mod);
 }
 
@@ -267,9 +243,9 @@ static void __mod_update_bounds(void *base, unsigned int size)
 
 static void mod_update_bounds(struct module *mod)
 {
-	__mod_update_bounds(mod->module_core, mod->core_size);
-	if (mod->init_size)
-		__mod_update_bounds(mod->module_init, mod->init_size);
+	__mod_update_bounds(mod->core_layout.base, mod->core_layout.size);
+	if (mod->init_layout.size)
+		__mod_update_bounds(mod->init_layout.base, mod->init_layout.size);
 }
 
 #ifdef CONFIG_KGDB_KDB
@@ -1214,7 +1190,7 @@ struct module_attribute module_uevent =
 static ssize_t show_coresize(struct module_attribute *mattr,
 			     struct module_kobject *mk, char *buffer)
 {
-	return sprintf(buffer, "%u\n", mk->mod->core_size);
+	return sprintf(buffer, "%u\n", mk->mod->core_layout.size);
 }
 
 static struct module_attribute modinfo_coresize =
@@ -1223,7 +1199,7 @@ static struct module_attribute modinfo_coresize =
 static ssize_t show_initsize(struct module_attribute *mattr,
 			     struct module_kobject *mk, char *buffer)
 {
-	return sprintf(buffer, "%u\n", mk->mod->init_size);
+	return sprintf(buffer, "%u\n", mk->mod->init_layout.size);
 }
 
 static struct module_attribute modinfo_initsize =
@@ -1873,64 +1849,75 @@ static void mod_sysfs_teardown(struct module *mod)
 /*
  * LKM RO/NX protection: protect module's text/ro-data
  * from modification and any data from execution.
+ *
+ * General layout of module is:
+ *          [text] [read-only-data] [writable data]
+ * text_size -----^                ^               ^
+ * ro_size ------------------------|               |
+ * size -------------------------------------------|
+ *
+ * These values are always page-aligned (as is base)
  */
-void set_page_attributes(void *start, void *end, int (*set)(unsigned long start, int num_pages))
+static void frob_text(const struct module_layout *layout,
+		      int (*set_memory)(unsigned long start, int num_pages))
 {
-	unsigned long begin_pfn = PFN_DOWN((unsigned long)start);
-	unsigned long end_pfn = PFN_DOWN((unsigned long)end);
+	BUG_ON((unsigned long)layout->base & (PAGE_SIZE-1));
+	BUG_ON((unsigned long)layout->text_size & (PAGE_SIZE-1));
+	set_memory((unsigned long)layout->base,
+		   layout->text_size >> PAGE_SHIFT);
+}
 
-	if (end_pfn > begin_pfn)
-		set(begin_pfn << PAGE_SHIFT, end_pfn - begin_pfn);
+static void frob_rodata(const struct module_layout *layout,
+			int (*set_memory)(unsigned long start, int num_pages))
+{
+	BUG_ON((unsigned long)layout->base & (PAGE_SIZE-1));
+	BUG_ON((unsigned long)layout->text_size & (PAGE_SIZE-1));
+	BUG_ON((unsigned long)layout->ro_size & (PAGE_SIZE-1));
+	set_memory((unsigned long)layout->base + layout->text_size,
+		   (layout->ro_size - layout->text_size) >> PAGE_SHIFT);
 }
 
-static void set_section_ro_nx(void *base,
-			unsigned long text_size,
-			unsigned long ro_size,
-			unsigned long total_size)
+static void frob_writable_data(const struct module_layout *layout,
+			       int (*set_memory)(unsigned long start, int num_pages))
 {
-	/* begin and end PFNs of the current subsection */
-	unsigned long begin_pfn;
-	unsigned long end_pfn;
+	BUG_ON((unsigned long)layout->base & (PAGE_SIZE-1));
+	BUG_ON((unsigned long)layout->ro_size & (PAGE_SIZE-1));
+	BUG_ON((unsigned long)layout->size & (PAGE_SIZE-1));
+	set_memory((unsigned long)layout->base + layout->ro_size,
+		   (layout->size - layout->ro_size) >> PAGE_SHIFT);
+}
 
-	/*
-	 * Set RO for module text and RO-data:
-	 * - Always protect first page.
-	 * - Do not protect last partial page.
-	 */
-	if (ro_size > 0)
-		set_page_attributes(base, base + ro_size, set_memory_ro);
+/* livepatching wants to disable read-only so it can frob module. */
+void module_disable_ro(const struct module *mod)
+{
+	frob_text(&mod->core_layout, set_memory_rw);
+	frob_rodata(&mod->core_layout, set_memory_rw);
+	frob_text(&mod->init_layout, set_memory_rw);
+	frob_rodata(&mod->init_layout, set_memory_rw);
+}
 
-	/*
-	 * Set NX permissions for module data:
-	 * - Do not protect first partial page.
-	 * - Always protect last page.
-	 */
-	if (total_size > text_size) {
-		begin_pfn = PFN_UP((unsigned long)base + text_size);
-		end_pfn = PFN_UP((unsigned long)base + total_size);
-		if (end_pfn > begin_pfn)
-			set_memory_nx(begin_pfn << PAGE_SHIFT, end_pfn - begin_pfn);
-	}
+void module_enable_ro(const struct module *mod)
+{
+	frob_text(&mod->core_layout, set_memory_ro);
+	frob_rodata(&mod->core_layout, set_memory_ro);
+	frob_text(&mod->init_layout, set_memory_ro);
+	frob_rodata(&mod->init_layout, set_memory_ro);
 }
 
-static void unset_module_core_ro_nx(struct module *mod)
+static void module_enable_nx(const struct module *mod)
 {
-	set_page_attributes(mod->module_core + mod->core_text_size,
-		mod->module_core + mod->core_size,
-		set_memory_x);
-	set_page_attributes(mod->module_core,
-		mod->module_core + mod->core_ro_size,
-		set_memory_rw);
+	frob_rodata(&mod->core_layout, set_memory_nx);
+	frob_writable_data(&mod->core_layout, set_memory_nx);
+	frob_rodata(&mod->init_layout, set_memory_nx);
+	frob_writable_data(&mod->init_layout, set_memory_nx);
 }
 
-static void unset_module_init_ro_nx(struct module *mod)
+static void module_disable_nx(const struct module *mod)
 {
-	set_page_attributes(mod->module_init + mod->init_text_size,
-		mod->module_init + mod->init_size,
-		set_memory_x);
-	set_page_attributes(mod->module_init,
-		mod->module_init + mod->init_ro_size,
-		set_memory_rw);
+	frob_rodata(&mod->core_layout, set_memory_x);
+	frob_writable_data(&mod->core_layout, set_memory_x);
+	frob_rodata(&mod->init_layout, set_memory_x);
+	frob_writable_data(&mod->init_layout, set_memory_x);
 }
 
 /* Iterate through all modules and set each module's text as RW */
@@ -1942,16 +1929,9 @@ void set_all_modules_text_rw(void)
 	list_for_each_entry_rcu(mod, &modules, list) {
 		if (mod->state == MODULE_STATE_UNFORMED)
 			continue;
-		if ((mod->module_core) && (mod->core_text_size)) {
-			set_page_attributes(mod->module_core,
-						mod->module_core + mod->core_text_size,
-						set_memory_rw);
-		}
-		if ((mod->module_init) && (mod->init_text_size)) {
-			set_page_attributes(mod->module_init,
-						mod->module_init + mod->init_text_size,
-						set_memory_rw);
-		}
+
+		frob_text(&mod->core_layout, set_memory_rw);
+		frob_text(&mod->init_layout, set_memory_rw);
 	}
 	mutex_unlock(&module_mutex);
 }
@@ -1965,23 +1945,25 @@ void set_all_modules_text_ro(void)
 	list_for_each_entry_rcu(mod, &modules, list) {
 		if (mod->state == MODULE_STATE_UNFORMED)
 			continue;
-		if ((mod->module_core) && (mod->core_text_size)) {
-			set_page_attributes(mod->module_core,
-						mod->module_core + mod->core_text_size,
-						set_memory_ro);
-		}
-		if ((mod->module_init) && (mod->init_text_size)) {
-			set_page_attributes(mod->module_init,
-						mod->module_init + mod->init_text_size,
-						set_memory_ro);
-		}
+
+		frob_text(&mod->core_layout, set_memory_ro);
+		frob_text(&mod->init_layout, set_memory_ro);
 	}
 	mutex_unlock(&module_mutex);
 }
+
+static void disable_ro_nx(const struct module_layout *layout)
+{
+	frob_text(layout, set_memory_rw);
+	frob_rodata(layout, set_memory_rw);
+	frob_rodata(layout, set_memory_x);
+	frob_writable_data(layout, set_memory_x);
+}
+
 #else
-static inline void set_section_ro_nx(void *base, unsigned long text_size, unsigned long ro_size, unsigned long total_size) { }
-static void unset_module_core_ro_nx(struct module *mod) { }
-static void unset_module_init_ro_nx(struct module *mod) { }
+static void disable_ro_nx(const struct module_layout *layout) { }
+static void module_enable_nx(const struct module *mod) { }
+static void module_disable_nx(const struct module *mod) { }
 #endif
 
 void __weak module_memfree(void *module_region)
@@ -2033,19 +2015,19 @@ static void free_module(struct module *mod)
 	synchronize_sched();
 	mutex_unlock(&module_mutex);
 
-	/* This may be NULL, but that's OK */
-	unset_module_init_ro_nx(mod);
+	/* This may be empty, but that's OK */
+	disable_ro_nx(&mod->init_layout);
 	module_arch_freeing_init(mod);
-	module_memfree(mod->module_init);
+	module_memfree(mod->init_layout.base);
 	kfree(mod->args);
 	percpu_modfree(mod);
 
 	/* Free lock-classes; relies on the preceding sync_rcu(). */
-	lockdep_free_key_range(mod->module_core, mod->core_size);
+	lockdep_free_key_range(mod->core_layout.base, mod->core_layout.size);
 
 	/* Finally, free the core (containing the module structure) */
-	unset_module_core_ro_nx(mod);
-	module_memfree(mod->module_core);
+	disable_ro_nx(&mod->core_layout);
+	module_memfree(mod->core_layout.base);
 
 #ifdef CONFIG_MPU
 	update_protections(current->mm);
@@ -2248,20 +2230,20 @@ static void layout_sections(struct module *mod, struct load_info *info)
 			    || s->sh_entsize != ~0UL
 			    || strstarts(sname, ".init"))
 				continue;
-			s->sh_entsize = get_offset(mod, &mod->core_size, s, i);
+			s->sh_entsize = get_offset(mod, &mod->core_layout.size, s, i);
 			pr_debug("\t%s\n", sname);
 		}
 		switch (m) {
 		case 0: /* executable */
-			mod->core_size = debug_align(mod->core_size);
-			mod->core_text_size = mod->core_size;
+			mod->core_layout.size = debug_align(mod->core_layout.size);
+			mod->core_layout.text_size = mod->core_layout.size;
 			break;
 		case 1: /* RO: text and ro-data */
-			mod->core_size = debug_align(mod->core_size);
-			mod->core_ro_size = mod->core_size;
+			mod->core_layout.size = debug_align(mod->core_layout.size);
+			mod->core_layout.ro_size = mod->core_layout.size;
 			break;
 		case 3: /* whole core */
-			mod->core_size = debug_align(mod->core_size);
+			mod->core_layout.size = debug_align(mod->core_layout.size);
 			break;
 		}
 	}
@@ -2277,21 +2259,21 @@ static void layout_sections(struct module *mod, struct load_info *info)
 			    || s->sh_entsize != ~0UL
 			    || !strstarts(sname, ".init"))
 				continue;
-			s->sh_entsize = (get_offset(mod, &mod->init_size, s, i)
+			s->sh_entsize = (get_offset(mod, &mod->init_layout.size, s, i)
 					 | INIT_OFFSET_MASK);
 			pr_debug("\t%s\n", sname);
 		}
 		switch (m) {
 		case 0: /* executable */
-			mod->init_size = debug_align(mod->init_size);
-			mod->init_text_size = mod->init_size;
+			mod->init_layout.size = debug_align(mod->init_layout.size);
+			mod->init_layout.text_size = mod->init_layout.size;
 			break;
 		case 1: /* RO: text and ro-data */
-			mod->init_size = debug_align(mod->init_size);
-			mod->init_ro_size = mod->init_size;
+			mod->init_layout.size = debug_align(mod->init_layout.size);
+			mod->init_layout.ro_size = mod->init_layout.size;
 			break;
 		case 3: /* whole init */
-			mod->init_size = debug_align(mod->init_size);
+			mod->init_layout.size = debug_align(mod->init_layout.size);
 			break;
 		}
 	}
@@ -2401,7 +2383,7 @@ static char elf_type(const Elf_Sym *sym, const struct load_info *info)
 	}
 	if (sym->st_shndx == SHN_UNDEF)
 		return 'U';
-	if (sym->st_shndx == SHN_ABS)
+	if (sym->st_shndx == SHN_ABS || sym->st_shndx == info->index.pcpu)
 		return 'a';
 	if (sym->st_shndx >= SHN_LORESERVE)
 		return '?';
@@ -2430,7 +2412,7 @@ static char elf_type(const Elf_Sym *sym, const struct load_info *info)
 }
 
 static bool is_core_symbol(const Elf_Sym *src, const Elf_Shdr *sechdrs,
-			unsigned int shnum)
+			unsigned int shnum, unsigned int pcpundx)
 {
 	const Elf_Shdr *sec;
 
@@ -2439,6 +2421,11 @@ static bool is_core_symbol(const Elf_Sym *src, const Elf_Shdr *sechdrs,
 	    || !src->st_name)
 		return false;
 
+#ifdef CONFIG_KALLSYMS_ALL
+	if (src->st_shndx == pcpundx)
+		return true;
+#endif
+
 	sec = sechdrs + src->st_shndx;
 	if (!(sec->sh_flags & SHF_ALLOC)
 #ifndef CONFIG_KALLSYMS_ALL
@@ -2466,7 +2453,7 @@ static void layout_symtab(struct module *mod, struct load_info *info)
 
 	/* Put symbol section at end of init part of module. */
 	symsect->sh_flags |= SHF_ALLOC;
-	symsect->sh_entsize = get_offset(mod, &mod->init_size, symsect,
+	symsect->sh_entsize = get_offset(mod, &mod->init_layout.size, symsect,
 					 info->index.sym) | INIT_OFFSET_MASK;
 	pr_debug("\t%s\n", info->secstrings + symsect->sh_name);
 
@@ -2476,23 +2463,24 @@ static void layout_symtab(struct module *mod, struct load_info *info)
 	/* Compute total space required for the core symbols' strtab. */
 	for (ndst = i = 0; i < nsrc; i++) {
 		if (i == 0 ||
-		    is_core_symbol(src+i, info->sechdrs, info->hdr->e_shnum)) {
+		    is_core_symbol(src+i, info->sechdrs, info->hdr->e_shnum,
+				   info->index.pcpu)) {
 			strtab_size += strlen(&info->strtab[src[i].st_name])+1;
 			ndst++;
 		}
 	}
 
 	/* Append room for core symbols at end of core part. */
-	info->symoffs = ALIGN(mod->core_size, symsect->sh_addralign ?: 1);
-	info->stroffs = mod->core_size = info->symoffs + ndst * sizeof(Elf_Sym);
-	mod->core_size += strtab_size;
-	mod->core_size = debug_align(mod->core_size);
+	info->symoffs = ALIGN(mod->core_layout.size, symsect->sh_addralign ?: 1);
+	info->stroffs = mod->core_layout.size = info->symoffs + ndst * sizeof(Elf_Sym);
+	mod->core_layout.size += strtab_size;
+	mod->core_layout.size = debug_align(mod->core_layout.size);
 
 	/* Put string table section at end of init part of module. */
 	strsect->sh_flags |= SHF_ALLOC;
-	strsect->sh_entsize = get_offset(mod, &mod->init_size, strsect,
+	strsect->sh_entsize = get_offset(mod, &mod->init_layout.size, strsect,
 					 info->index.str) | INIT_OFFSET_MASK;
-	mod->init_size = debug_align(mod->init_size);
+	mod->init_layout.size = debug_align(mod->init_layout.size);
 	pr_debug("\t%s\n", info->secstrings + strsect->sh_name);
 }
 
@@ -2513,12 +2501,13 @@ static void add_kallsyms(struct module *mod, const struct load_info *info)
 	for (i = 0; i < mod->num_symtab; i++)
 		mod->symtab[i].st_info = elf_type(&mod->symtab[i], info);
 
-	mod->core_symtab = dst = mod->module_core + info->symoffs;
-	mod->core_strtab = s = mod->module_core + info->stroffs;
+	mod->core_symtab = dst = mod->core_layout.base + info->symoffs;
+	mod->core_strtab = s = mod->core_layout.base + info->stroffs;
 	src = mod->symtab;
 	for (ndst = i = 0; i < mod->num_symtab; i++) {
 		if (i == 0 ||
-		    is_core_symbol(src+i, info->sechdrs, info->hdr->e_shnum)) {
+		    is_core_symbol(src+i, info->sechdrs, info->hdr->e_shnum,
+				   info->index.pcpu)) {
 			dst[ndst] = src[i];
 			dst[ndst++].st_name = s - mod->core_strtab;
 			s += strlcpy(s, &mod->strtab[src[i].st_name],
@@ -2964,7 +2953,7 @@ static int move_module(struct module *mod, struct load_info *info)
 	void *ptr;
 
 	/* Do the allocs. */
-	ptr = module_alloc(mod->core_size);
+	ptr = module_alloc(mod->core_layout.size);
 	/*
 	 * The pointer to this block is stored in the module structure
 	 * which is inside the block. Just mark it as not being a
@@ -2974,11 +2963,11 @@ static int move_module(struct module *mod, struct load_info *info)
 	if (!ptr)
 		return -ENOMEM;
 
-	memset(ptr, 0, mod->core_size);
-	mod->module_core = ptr;
+	memset(ptr, 0, mod->core_layout.size);
+	mod->core_layout.base = ptr;
 
-	if (mod->init_size) {
-		ptr = module_alloc(mod->init_size);
+	if (mod->init_layout.size) {
+		ptr = module_alloc(mod->init_layout.size);
 		/*
 		 * The pointer to this block is stored in the module structure
 		 * which is inside the block. This block doesn't need to be
@@ -2987,13 +2976,13 @@ static int move_module(struct module *mod, struct load_info *info)
 		 */
 		kmemleak_ignore(ptr);
 		if (!ptr) {
-			module_memfree(mod->module_core);
+			module_memfree(mod->core_layout.base);
 			return -ENOMEM;
 		}
-		memset(ptr, 0, mod->init_size);
-		mod->module_init = ptr;
+		memset(ptr, 0, mod->init_layout.size);
+		mod->init_layout.base = ptr;
 	} else
-		mod->module_init = NULL;
+		mod->init_layout.base = NULL;
 
 	/* Transfer each section which specifies SHF_ALLOC */
 	pr_debug("final section addresses:\n");
@@ -3005,10 +2994,10 @@ static int move_module(struct module *mod, struct load_info *info)
 			continue;
 
 		if (shdr->sh_entsize & INIT_OFFSET_MASK)
-			dest = mod->module_init
+			dest = mod->init_layout.base
 				+ (shdr->sh_entsize & ~INIT_OFFSET_MASK);
 		else
-			dest = mod->module_core + shdr->sh_entsize;
+			dest = mod->core_layout.base + shdr->sh_entsize;
 
 		if (shdr->sh_type != SHT_NOBITS)
 			memcpy(dest, (void *)shdr->sh_addr, shdr->sh_size);
@@ -3070,12 +3059,12 @@ static void flush_module_icache(const struct module *mod)
 	 * Do it before processing of module parameters, so the module
 	 * can provide parameter accessor functions of its own.
 	 */
-	if (mod->module_init)
-		flush_icache_range((unsigned long)mod->module_init,
-				   (unsigned long)mod->module_init
-				   + mod->init_size);
-	flush_icache_range((unsigned long)mod->module_core,
-			   (unsigned long)mod->module_core + mod->core_size);
+	if (mod->init_layout.base)
+		flush_icache_range((unsigned long)mod->init_layout.base,
+				   (unsigned long)mod->init_layout.base
+				   + mod->init_layout.size);
+	flush_icache_range((unsigned long)mod->core_layout.base,
+			   (unsigned long)mod->core_layout.base + mod->core_layout.size);
 
 	set_fs(old_fs);
 }
@@ -3133,8 +3122,8 @@ static void module_deallocate(struct module *mod, struct load_info *info)
 {
 	percpu_modfree(mod);
 	module_arch_freeing_init(mod);
-	module_memfree(mod->module_init);
-	module_memfree(mod->module_core);
+	module_memfree(mod->init_layout.base);
+	module_memfree(mod->core_layout.base);
 }
 
 int __weak module_finalize(const Elf_Ehdr *hdr,
@@ -3221,7 +3210,7 @@ static noinline int do_init_module(struct module *mod)
 		ret = -ENOMEM;
 		goto fail;
 	}
-	freeinit->module_init = mod->module_init;
+	freeinit->module_init = mod->init_layout.base;
 
 	/*
 	 * We want to find out whether @mod uses async during init.  Clear
@@ -3279,12 +3268,12 @@ static noinline int do_init_module(struct module *mod)
 	mod->strtab = mod->core_strtab;
 #endif
 	mod_tree_remove_init(mod);
-	unset_module_init_ro_nx(mod);
+	disable_ro_nx(&mod->init_layout);
 	module_arch_freeing_init(mod);
-	mod->module_init = NULL;
-	mod->init_size = 0;
-	mod->init_ro_size = 0;
-	mod->init_text_size = 0;
+	mod->init_layout.base = NULL;
+	mod->init_layout.size = 0;
+	mod->init_layout.ro_size = 0;
+	mod->init_layout.text_size = 0;
 	/*
 	 * We want to free module_init, but be aware that kallsyms may be
 	 * walking this with preempt disabled.  In all the failure paths, we
@@ -3373,17 +3362,9 @@ static int complete_formation(struct module *mod, struct load_info *info)
 	/* This relies on module_mutex for list integrity. */
 	module_bug_finalize(info->hdr, info->sechdrs, mod);
 
-	/* Set RO and NX regions for core */
-	set_section_ro_nx(mod->module_core,
-				mod->core_text_size,
-				mod->core_ro_size,
-				mod->core_size);
-
-	/* Set RO and NX regions for init */
-	set_section_ro_nx(mod->module_init,
-				mod->init_text_size,
-				mod->init_ro_size,
-				mod->init_size);
+	/* Set RO and NX regions */
+	module_enable_ro(mod);
+	module_enable_nx(mod);
 
 	/* Mark state as coming so strong_try_module_get() ignores us,
 	 * but kallsyms etc. can see us. */
@@ -3548,8 +3529,8 @@ static int load_module(struct load_info *info, const char __user *uargs,
 				     MODULE_STATE_GOING, mod);
 
 	/* we can't deallocate the module until we clear memory protection */
-	unset_module_init_ro_nx(mod);
-	unset_module_core_ro_nx(mod);
+	module_disable_ro(mod);
+	module_disable_nx(mod);
 
  ddebug_cleanup:
 	dynamic_debug_remove(info->debug);
@@ -3578,7 +3559,7 @@ static int load_module(struct load_info *info, const char __user *uargs,
 	 */
 	ftrace_release_mod(mod);
 	/* Free lock-classes; relies on the preceding sync_rcu() */
-	lockdep_free_key_range(mod->module_core, mod->core_size);
+	lockdep_free_key_range(mod->core_layout.base, mod->core_layout.size);
 
 	module_deallocate(mod, info);
  free_copy:
@@ -3656,9 +3637,9 @@ static const char *get_ksymbol(struct module *mod,
 
 	/* At worse, next value is at end of module */
 	if (within_module_init(addr, mod))
-		nextval = (unsigned long)mod->module_init+mod->init_text_size;
+		nextval = (unsigned long)mod->init_layout.base+mod->init_layout.text_size;
 	else
-		nextval = (unsigned long)mod->module_core+mod->core_text_size;
+		nextval = (unsigned long)mod->core_layout.base+mod->core_layout.text_size;
 
 	/* Scan for closest preceding symbol, and next symbol. (ELF
 	   starts real symbols at 1). */
@@ -3905,7 +3886,7 @@ static int m_show(struct seq_file *m, void *p)
 		return 0;
 
 	seq_printf(m, "%s %u",
-		   mod->name, mod->init_size + mod->core_size);
+		   mod->name, mod->init_layout.size + mod->core_layout.size);
 	print_unload_info(m, mod);
 
 	/* Informative for users. */
@@ -3914,7 +3895,7 @@ static int m_show(struct seq_file *m, void *p)
 		   mod->state == MODULE_STATE_COMING ? "Loading" :
 		   "Live");
 	/* Used by oprofile and other similar tools. */
-	seq_printf(m, " 0x%pK", mod->module_core);
+	seq_printf(m, " 0x%pK", mod->core_layout.base);
 
 	/* Taints info */
 	if (mod->taints)
@@ -4057,8 +4038,8 @@ struct module *__module_text_address(unsigned long addr)
 	struct module *mod = __module_address(addr);
 	if (mod) {
 		/* Make sure it's within the text section. */
-		if (!within(addr, mod->module_init, mod->init_text_size)
-		    && !within(addr, mod->module_core, mod->core_text_size))
+		if (!within(addr, mod->init_layout.base, mod->init_layout.text_size)
+		    && !within(addr, mod->core_layout.base, mod->core_layout.text_size))
 			mod = NULL;
 	}
 	return mod;