diff --git a/arch/Kconfig b/arch/Kconfig
index 6c00e5b..9d16b51 100644
--- a/arch/Kconfig
+++ b/arch/Kconfig
@@ -228,6 +228,7 @@ config GENERIC_IDLE_POLL_SETUP
 
 # Select if arch has all set_memory_ro/rw/x/nx() functions in asm/cacheflush.h
 config ARCH_HAS_SET_MEMORY
+	select GENERIC_ALLOCATOR
 	bool
 
 # Select if arch init_task initializer is different to init/init_task.c
diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h
index 6b5818d..acc0723 100644
--- a/include/linux/page-flags.h
+++ b/include/linux/page-flags.h
@@ -81,6 +81,7 @@ enum pageflags {
 	PG_active,
 	PG_waiters,		/* Page has waiters, check its waitqueue. Must be bit #7 and in the same byte as "PG_locked" */
 	PG_slab,
+	PG_pmalloc,
 	PG_owner_priv_1,	/* Owner use. If pagecache, fs may use*/
 	PG_arch_1,
 	PG_reserved,
@@ -274,6 +275,7 @@ PAGEFLAG(Active, active, PF_HEAD) __CLEARPAGEFLAG(Active, active, PF_HEAD)
 	TESTCLEARFLAG(Active, active, PF_HEAD)
 __PAGEFLAG(Slab, slab, PF_NO_TAIL)
 __PAGEFLAG(SlobFree, slob_free, PF_NO_TAIL)
+__PAGEFLAG(Pmalloc, pmalloc, PF_NO_TAIL)
 PAGEFLAG(Checked, checked, PF_NO_COMPOUND)	   /* Used by some filesystems */
 
 /* Xen */
diff --git a/include/linux/pmalloc.h b/include/linux/pmalloc.h
new file mode 100644
index 0000000..0d65f83
--- /dev/null
+++ b/include/linux/pmalloc.h
@@ -0,0 +1,111 @@
+/*
+ * pmalloc.h: Header for Protectable Memory Allocator
+ *
+ * (C) Copyright 2017 Huawei Technologies Co. Ltd.
+ * Author: Igor Stoppa <igor.stoppa@huawei.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; version 2
+ * of the License.
+ */
+
+#ifndef _PMALLOC_H
+#define _PMALLOC_H
+#include <linux/genalloc.h>
+
+#define PMALLOC_DEFAULT_ALLOC_ORDER (-1)
+
+/**
+ * pmalloc_create_pool - create a new protectable memory pool -
+ * @name: the name of the pool, must be unique
+ * @min_alloc_order: log2 of the minimum allocation size obtainable
+ *                   from the pool
+ *
+ * Creates a new (empty) memory pool for allocation of protectable
+ * memory. Memory will be allocated upon request (through pmalloc).
+ *
+ * Returns a pointer to the new pool, upon succes, otherwise a NULL.
+ */
+struct gen_pool *pmalloc_create_pool(const char *name,
+					 int min_alloc_order);
+
+
+/**
+ * pmalloc_get_pool - get a pool handler, from its name
+ * @name: the name of the pool sought after.
+ *
+ * Returns a pointer to the pool, upon succes, otherwise a NULL.
+ */
+struct gen_pool *pmalloc_get_pool(const char *name);
+
+
+
+/**
+ * pmalloc - allocate protectable memory from a pool
+ * @pool: handler to the pool to be used for memory allocation
+ * @size: amount of memory (in bytes) requested
+ *
+ * Allocates memory from an unprotected pool. If the pool doesn't have
+ * enough memory, an attempt is made to add to the pool a new chunk of
+ * memory (multiple of PAGE_SIZE) that can fit the new request.
+ *
+ * Returns the pointer to the memory requested, upon success,
+ * NULL otherwise (either no memory availabel or pool RO).
+ */
+void *pmalloc(struct gen_pool *pool, size_t size);
+
+
+
+/**
+ * pmalloc_free - release memory previously obtained through pmalloc
+ * @pool: the pool providing the memory
+ * @addr: the memory address obtained from pmalloc
+ * @size: the same amount of memory that was requested from pmalloc
+ *
+ * Releases the memory that was previously accounted for as in use.
+ * It works also on pocked pools, but the memory released is simply
+ * removed from the refcount of memory in use. It cannot be re-used.
+ */
+static __always_inline
+void pmalloc_free(struct gen_pool *pool, void *addr, size_t size)
+{
+	gen_pool_free(pool, (unsigned long)addr, size);
+}
+
+
+
+/**
+ * pmalloc_protect_pool - turn a RW pool into RO
+ * @pool: the pool to protect
+ *
+ * Write protects all the memory chunks assigned to the pool.
+ * This prevents further allocation.
+ *
+ * Returns 0 upon success, -EINVAL in abnormal cases.
+ */
+int pmalloc_protect_pool(struct gen_pool *pool);
+
+
+
+/**
+ * pmalloc_pool_protected - check if the pool is protected
+ * @pool: the pool to test
+ *
+ * Returns true if the pool is either protected or missing. False otherwise.
+ */
+bool pmalloc_pool_protected(struct gen_pool *pool);
+
+
+
+/**
+ * pmalloc_destroy_pool - destroys a pool and all the associated memory
+ * @pool: the pool to destroy
+ *
+ * All the memory that was allocated through pmalloc must first be freed
+ * with pmalloc_free. Falire to do so will BUG().
+ *
+ * Returns 0 upon success, -EINVAL in abnormal cases.
+ */
+int pmalloc_destroy_pool(struct gen_pool *pool);
+#endif
diff --git a/include/trace/events/mmflags.h b/include/trace/events/mmflags.h
index 304ff94..41d1587 100644
--- a/include/trace/events/mmflags.h
+++ b/include/trace/events/mmflags.h
@@ -91,6 +91,7 @@
 	{1UL << PG_lru,			"lru"		},		\
 	{1UL << PG_active,		"active"	},		\
 	{1UL << PG_slab,		"slab"		},		\
+	{1UL << PG_pmalloc,		"pmalloc"	},		\
 	{1UL << PG_owner_priv_1,	"owner_priv_1"	},		\
 	{1UL << PG_arch_1,		"arch_1"	},		\
 	{1UL << PG_reserved,		"reserved"	},		\
diff --git a/init/main.c b/init/main.c
index f866510..a703c9c 100644
--- a/init/main.c
+++ b/init/main.c
@@ -100,6 +100,7 @@ static int kernel_init(void *);
 extern void init_IRQ(void);
 extern void fork_init(void);
 extern void radix_tree_init(void);
+int __init pmalloc_init(void);
 
 /*
  * Debug helper: via this flag we know that we are in 'early bootup code'
@@ -653,6 +654,7 @@ asmlinkage __visible void __init start_kernel(void)
 	proc_caches_init();
 	buffer_init();
 	key_init();
+	pmalloc_init();
 	security_init();
 	dbg_late_init();
 	vfs_caches_init();
diff --git a/lib/Kconfig b/lib/Kconfig
index 0c8b78a..3e3b8f6 100644
--- a/lib/Kconfig
+++ b/lib/Kconfig
@@ -270,6 +270,7 @@ config DECOMPRESS_LZ4
 # Generic allocator support is selected if needed
 #
 config GENERIC_ALLOCATOR
+	depends on ARCH_HAS_SET_MEMORY
 	bool
 
 #
diff --git a/lib/genalloc.c b/lib/genalloc.c
index 144fe6b..52165bb 100644
--- a/lib/genalloc.c
+++ b/lib/genalloc.c
@@ -648,12 +648,12 @@ unsigned long gen_pool_best_fit(unsigned long *map, unsigned long size,
 }
 EXPORT_SYMBOL(gen_pool_best_fit);
 
-static void devm_gen_pool_release(struct device *dev, void *res)
+void devm_gen_pool_release(struct device *dev, void *res)
 {
 	gen_pool_destroy(*(struct gen_pool **)res);
 }
 
-static int devm_gen_pool_match(struct device *dev, void *res, void *data)
+int devm_gen_pool_match(struct device *dev, void *res, void *data)
 {
 	struct gen_pool **p = res;
 
diff --git a/mm/Makefile b/mm/Makefile
index 026f6a8..b47dcf8 100644
--- a/mm/Makefile
+++ b/mm/Makefile
@@ -65,6 +65,7 @@ obj-$(CONFIG_SPARSEMEM)	+= sparse.o
 obj-$(CONFIG_SPARSEMEM_VMEMMAP) += sparse-vmemmap.o
 obj-$(CONFIG_SLOB) += slob.o
 obj-$(CONFIG_MMU_NOTIFIER) += mmu_notifier.o
+obj-$(CONFIG_ARCH_HAS_SET_MEMORY) += pmalloc.o
 obj-$(CONFIG_KSM) += ksm.o
 obj-$(CONFIG_PAGE_POISONING) += page_poison.o
 obj-$(CONFIG_SLAB) += slab.o
diff --git a/mm/pmalloc.c b/mm/pmalloc.c
new file mode 100644
index 0000000..cb56ae3
--- /dev/null
+++ b/mm/pmalloc.c
@@ -0,0 +1,341 @@
+/*
+ * pmalloc.c: Protectable Memory Allocator
+ *
+ * (C) Copyright 2017 Huawei Technologies Co. Ltd.
+ * Author: Igor Stoppa <igor.stoppa@huawei.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; version 2
+ * of the License.
+ */
+
+#include <linux/printk.h>
+#include <linux/init.h>
+#include <linux/mm.h>
+#include <linux/vmalloc.h>
+#include <linux/genalloc.h>
+#include <linux/kernel.h>
+#include <linux/log2.h>
+#include <linux/slab.h>
+#include <linux/device.h>
+#include <linux/atomic.h>
+#include <linux/rculist.h>
+#include <asm/set_memory.h>
+#include <asm/page.h>
+
+#include <linux/debugfs.h>
+#include <linux/kallsyms.h>
+
+
+/**
+ * pmalloc_data contains the data specific to a pmalloc pool,
+ * in a format compatible with the design of gen_alloc.
+ * Some of the fields are used for exposing the corresponding parameter
+ * to userspace, through sysfs.
+ */
+struct pmalloc_data {
+	struct gen_pool *pool;  /* Link back to the associated pool. */
+	atomic_t protected;     /* Status of the pool: RO or RW. */
+	atomic_t processed;     /* Is the pool already in sysfs? */
+	struct kobj_attribute attr_protected; /* Sysfs attribute. */
+	struct kobj_attribute attr_avail;     /* Sysfs attribute. */
+	struct kobj_attribute attr_size;      /* Sysfs attribute. */
+	struct kobject *pool_kobject;
+};
+
+/**
+ * Keeps track of the safe point, where operatioms according to the normal
+ * device model are supported. Before this point, such operation are not
+ * available.
+ */
+static atomic_t into_post_init;
+
+static struct device pmalloc_dev;
+static struct kobject *pmalloc_kobject;
+
+static ssize_t __pmalloc_pool_show_protected(struct kobject *dev,
+					     struct kobj_attribute *attr,
+					     char *buf)
+{
+	struct pmalloc_data *data;
+
+	data = container_of(attr, struct pmalloc_data, attr_protected);
+	if (atomic_read(&data->protected))
+		return sprintf(buf, "protected\n");
+	else
+		return sprintf(buf, "unprotected\n");
+}
+
+static ssize_t __pmalloc_pool_show_avail(struct kobject *dev,
+					 struct kobj_attribute *attr,
+					 char *buf)
+{
+	struct pmalloc_data *data;
+
+	data = container_of(attr, struct pmalloc_data, attr_avail);
+	return sprintf(buf, "%lu\n", gen_pool_avail(data->pool));
+}
+
+static ssize_t __pmalloc_pool_show_size(struct kobject *dev,
+					struct kobj_attribute *attr,
+					char *buf)
+{
+	struct pmalloc_data *data;
+
+	data = container_of(attr, struct pmalloc_data, attr_size);
+	return sprintf(buf, "%lu\n", gen_pool_size(data->pool));
+}
+
+/**
+ * Exposes the pool and its attributes through sysfs.
+ */
+static void __pmalloc_connect(struct pmalloc_data *data)
+{
+	kobject_add(data->pool_kobject, pmalloc_kobject, "%s",
+		    kobject_name(data->pool_kobject));
+	sysfs_create_file(data->pool_kobject, &data->attr_protected.attr);
+	sysfs_create_file(data->pool_kobject, &data->attr_avail.attr);
+	sysfs_create_file(data->pool_kobject, &data->attr_size.attr);
+}
+
+/**
+ * Removes the pool and its attributes from sysfs.
+ */
+static void __pmalloc_disconnect(struct pmalloc_data *data)
+{
+	sysfs_remove_file(data->pool_kobject, &data->attr_protected.attr);
+	sysfs_remove_file(data->pool_kobject, &data->attr_avail.attr);
+	sysfs_remove_file(data->pool_kobject, &data->attr_size.attr);
+	kobject_put(data->pool_kobject);
+}
+
+/**
+ * Declares an attribute of the pool.
+ */
+#define __pmalloc_attr_init(data, attr_name) \
+{ \
+	data->attr_##attr_name.attr.name = #attr_name; \
+	data->attr_##attr_name.attr.mode = VERIFY_OCTAL_PERMISSIONS(0444); \
+	data->attr_##attr_name.show = __pmalloc_pool_show_##attr_name; \
+}
+
+struct gen_pool *pmalloc_create_pool(const char *name,
+					 int min_alloc_order)
+{
+	struct gen_pool *pool;
+	struct pmalloc_data *data;
+
+	data = kzalloc(sizeof(struct pmalloc_data), GFP_KERNEL);
+	if (!data)
+		return NULL;
+	if (min_alloc_order < 0)
+		min_alloc_order = ilog2(sizeof(unsigned long));
+	pool = devm_gen_pool_create(&pmalloc_dev, min_alloc_order,
+				    -1, name);
+	if (!pool) {
+		kfree(data);
+		return NULL;
+	}
+	atomic_set(&data->protected, false);
+	atomic_set(&data->processed, atomic_read(&into_post_init));
+	data->pool = pool;
+	__pmalloc_attr_init(data, protected);
+	__pmalloc_attr_init(data, avail);
+	__pmalloc_attr_init(data, size);
+	data->pool_kobject = kobject_create();
+	BUG_ON(!data->pool_kobject);
+	kobject_set_name(data->pool_kobject, "%s", name);
+	if (atomic_read(&data->processed)) /* Check sysfs availability. */
+		__pmalloc_connect(data);   /* After late init. */
+	pool->data = data;
+	return pool;
+}
+
+
+struct gen_pool *pmalloc_get_pool(const char *name)
+{
+	return gen_pool_get(&pmalloc_dev, name);
+}
+
+
+/**
+ * To support hardened usercopy, tag/untag pages supplied by pmalloc.
+ * Pages are tagged when added to a pool and untagged when removed
+ * from said pool.
+ */
+#define PMALLOC_TAG_PAGE true
+#define PMALLOC_UNTAG_PAGE false
+static inline
+int __pmalloc_tag_pages(void *base, const size_t size, const bool set_tag)
+{
+	void *end = base + size - 1;
+
+	do {
+		struct page *page;
+
+		if (!is_vmalloc_addr(base))
+			return -EINVAL;
+		page = vmalloc_to_page(base);
+		if (set_tag)
+			__SetPagePmalloc(page);
+		else
+			__ClearPagePmalloc(page);
+		base += PAGE_SIZE;
+	} while ((PAGE_MASK & (unsigned long)base) <=
+		 (PAGE_MASK & (unsigned long)end));
+	return 0;
+}
+
+
+static void __page_untag(struct gen_pool *pool,
+			 struct gen_pool_chunk *chunk, void *data)
+{
+	__pmalloc_tag_pages((void *)chunk->start_addr,
+			    chunk->end_addr - chunk->start_addr + 1,
+			    PMALLOC_UNTAG_PAGE);
+}
+
+void *pmalloc(struct gen_pool *pool, size_t size)
+{
+	void *retval, *chunk;
+	size_t chunk_size;
+
+	if (!size || !pool ||
+	    atomic_read(&((struct pmalloc_data *)pool->data)->protected))
+		return NULL;
+	retval = (void *)gen_pool_alloc(pool, size);
+	if (retval)
+		return retval;
+	chunk_size = roundup(size, PAGE_SIZE);
+	chunk = vmalloc(chunk_size);
+	if (!chunk)
+		return NULL;
+	__pmalloc_tag_pages(chunk, size, PMALLOC_TAG_PAGE);
+	BUG_ON(gen_pool_add_virt(pool, (unsigned long)chunk,
+				(phys_addr_t)NULL, chunk_size, -1));
+	return (void *)gen_pool_alloc(pool, size);
+}
+
+static void __page_protection(struct gen_pool *pool,
+			      struct gen_pool_chunk *chunk, void *data)
+{
+	unsigned long pages;
+
+	if (!data)
+		return;
+	pages = roundup(chunk->end_addr - chunk->start_addr + 1,
+			PAGE_SIZE) / PAGE_SIZE;
+	if (*(bool *)data)
+		set_memory_ro(chunk->start_addr, pages);
+	else
+		set_memory_rw(chunk->start_addr, pages);
+}
+
+static int __pmalloc_pool_protection(struct gen_pool *pool, bool protection)
+{
+	if (!pool)
+		return -EINVAL;
+	BUG_ON(atomic_read(&((struct pmalloc_data *)pool->data)->protected)
+	       == protection);
+	atomic_set(&((struct pmalloc_data *)pool->data)->protected, protection);
+	gen_pool_for_each_chunk(pool, __page_protection, &protection);
+	return 0;
+}
+
+int pmalloc_protect_pool(struct gen_pool *pool)
+{
+	return __pmalloc_pool_protection(pool, true);
+}
+
+
+bool pmalloc_pool_protected(struct gen_pool *pool)
+{
+	if (!pool)
+		return true;
+	return atomic_read(&(((struct pmalloc_data *)pool->data)->protected));
+}
+
+
+void devm_gen_pool_release(struct device *dev, void *res);
+int devm_gen_pool_match(struct device *dev, void *res, void *data);
+
+int pmalloc_destroy_pool(struct gen_pool *pool)
+{
+	struct gen_pool **p;
+	struct pmalloc_data *data;
+
+	data = (struct pmalloc_data *)pool->data;
+	p = devres_find(&pmalloc_dev, devm_gen_pool_release,
+			devm_gen_pool_match, (void *)pool->name);
+	if (!p)
+		return -EINVAL;
+	__pmalloc_pool_protection(pool, false);
+	gen_pool_for_each_chunk(pool, __page_untag, NULL);
+	devm_gen_pool_release(&pmalloc_dev, p);
+	__pmalloc_disconnect(data);
+	kfree(data);
+	return 0;
+}
+
+static const char msg[] = "Not a valid Pmalloc object.";
+const char *__pmalloc_check_object(const void *ptr, unsigned long n)
+{
+	unsigned long p;
+
+	p = (unsigned long)ptr;
+	n = p + n - 1;
+	for (; (PAGE_MASK & p) <= (PAGE_MASK & n); p += PAGE_SIZE) {
+		struct page *page;
+
+		if (!is_vmalloc_addr((void *)p))
+			return msg;
+		page = vmalloc_to_page((void *)p);
+		if (!(page && PagePmalloc(page)))
+			return msg;
+	}
+	return NULL;
+}
+EXPORT_SYMBOL(__pmalloc_check_object);
+
+
+/**
+ * Early init function, the main purpose is to create the device used
+ * in conjunction with genalloc, to track the pools as resources.
+ * It cannot register the device because it is called very early in the
+ * boot sequence and the sysfs is not yet fully initialized.
+ */
+int __init pmalloc_init(void)
+{
+	device_initialize(&pmalloc_dev);
+	dev_set_name(&pmalloc_dev, "%s", "pmalloc");
+	atomic_set(&into_post_init, false);
+	return 0;
+}
+
+static void __pmalloc_late_add(struct device *dev, void *pool_ptr, void *d)
+{
+	struct pmalloc_data *data;
+
+	data = (*(struct gen_pool **)pool_ptr)->data;
+	if (!atomic_read(&data->processed)) {
+		atomic_set(&data->processed, true);
+		__pmalloc_connect(data);
+	}
+}
+
+
+/**
+ * When the sysfs is ready for recieving registrations, connect all the
+ * pools previously created. Also enable further pools to be connected
+ * right away.
+ */
+static int __init pmalloc_late_init(void)
+{
+	pmalloc_kobject = kobject_create_and_add("pmalloc", kernel_kobj);
+	atomic_set(&into_post_init, true);
+	devres_for_each_res(&pmalloc_dev, devm_gen_pool_release,
+			    NULL, NULL, __pmalloc_late_add, NULL);
+	return 0;
+}
+late_initcall(pmalloc_late_init);
diff --git a/mm/usercopy.c b/mm/usercopy.c
index a9852b2..29bb691 100644
--- a/mm/usercopy.c
+++ b/mm/usercopy.c
@@ -195,22 +195,28 @@ static inline const char *check_page_span(const void *ptr, unsigned long n,
 	return NULL;
 }
 
+extern const char *__pmalloc_check_object(const void *ptr, unsigned long n);
+
 static inline const char *check_heap_object(const void *ptr, unsigned long n,
 					    bool to_user)
 {
 	struct page *page;
 
-	if (!virt_addr_valid(ptr))
-		return NULL;
-
-	page = virt_to_head_page(ptr);
-
-	/* Check slab allocator for flags and size. */
-	if (PageSlab(page))
-		return __check_heap_object(ptr, n, page);
+	if (virt_addr_valid(ptr)) {
+		page = virt_to_head_page(ptr);
 
+		/* Check slab allocator for flags and size. */
+		if (PageSlab(page))
+			return __check_heap_object(ptr, n, page);
 	/* Verify object does not incorrectly span multiple pages. */
-	return check_page_span(ptr, n, page, to_user);
+		return check_page_span(ptr, n, page, to_user);
+	}
+	if (likely(is_vmalloc_addr(ptr))) {
+		page = vmalloc_to_page(ptr);
+		if (unlikely(page && PagePmalloc(page)))
+			return __pmalloc_check_object(ptr, n);
+	}
+	return NULL;
 }
 
 /*
