diff --git a/kernel/resource.c b/kernel/resource.c
index e3f5680a564cf656ac0d5847f36b78291c31ade3..4126827db0bf8b8e843815bac4c6b1179a6a2963 100644
--- a/kernel/resource.c
+++ b/kernel/resource.c
@@ -2015,3 +2015,77 @@ static int __init iomem_init_inode(void)
 fs_initcall(iomem_init_inode);
 
 __setup("iomem=", strict_iomem);
+#ifdef CONFIG_FREE_RESERVED_MM
+int release_reserved_resource(resource_size_t start, resource_size_t end,
+		unsigned long flags, bool first_lvl)
+{
+	bool siblings_only = false;
+	struct resource *p;
+	struct resource *new_res = NULL;
+
+	if (start >= end)
+		return -EINVAL;
+
+	read_lock(&resource_lock);
+
+	for (p = iomem_resource.child; p; p = next_resource(p)) {
+		if (p->start > end) {
+			p = NULL;
+			break;
+		}
+
+		if (p->end < start)
+			continue;
+
+		if (p->end > end && p->child)
+			continue;
+
+		siblings_only = first_lvl;
+
+		if ((p->flags & flags) != flags)
+			continue;
+
+		break;
+	}
+
+	read_unlock(&resource_lock);
+
+	if (p) {
+		pr_info("p->start=%llx,p->end=%llx\n", p->start, p->end);
+		if (p->start == start && p->end == end) {
+			release_resource(p);
+		} else if (p->start == start && p->end != end) {
+			/* adjust the start */
+			adjust_resource(p, end + 1, p->end - end);
+		} else if (p->start != start && p->end == end) {
+			/* adjust the end */
+			adjust_resource(p, p->start, start - p->start);
+		} else {
+			/* split into entries - we need a new resource */
+			read_lock(&resource_lock);
+			new_res = alloc_resource(GFP_KERNEL);
+			if (!new_res)
+				alloc_resource(GFP_ATOMIC);
+			if (!new_res)
+				alloc_resource(GFP_KERNEL | __GFP_NOFAIL);
+			new_res->name = p->name;
+			new_res->start = end + 1;
+			new_res->end = p->end;
+			new_res->flags = p->flags;
+			new_res->parent = p->parent;
+			new_res->sibling = p->sibling;
+			new_res->child = NULL;
+			read_unlock(&resource_lock);
+
+			if (adjust_resource(p, p->start, start - p->start))
+				goto out;
+			p->sibling = new_res;
+			new_res = NULL;
+		}
+	}
+
+out:
+	free_resource(new_res);
+	return p ? 0 : -ENODEV;
+}
+#endif
diff --git a/nos/extend_features/free_reserved_mm/Kconfig b/nos/extend_features/free_reserved_mm/Kconfig
new file mode 100644
index 0000000000000000000000000000000000000000..1dfa7f48c169ad3c7fca383a953b0c486901f189
--- /dev/null
+++ b/nos/extend_features/free_reserved_mm/Kconfig
@@ -0,0 +1,5 @@
+config FREE_RESERVED_MM
+	bool "Free reserved memory after system start"
+	default n
+	help
+		Free reserved memory, while reserved memory must be mapped.
\ No newline at end of file
diff --git a/nos/extend_features/free_reserved_mm/Makefile b/nos/extend_features/free_reserved_mm/Makefile
new file mode 100644
index 0000000000000000000000000000000000000000..73e4e6a466fff532fd5722a24a18adea410434b0
--- /dev/null
+++ b/nos/extend_features/free_reserved_mm/Makefile
@@ -0,0 +1 @@
+obj-$(CONFIG_FREE_RESERVED_MM) += free_reserved_mm.o
\ No newline at end of file
diff --git a/nos/extend_features/free_reserved_mm/free_reserved_mm.c b/nos/extend_features/free_reserved_mm/free_reserved_mm.c
new file mode 100644
index 0000000000000000000000000000000000000000..982a3ecd224f07456dd005bda9292c68756906cf
--- /dev/null
+++ b/nos/extend_features/free_reserved_mm/free_reserved_mm.c
@@ -0,0 +1,74 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+#include <linux/pfn.h>
+#include <linux/kernel.h>
+#include <linux/memblock.h>
+#include <asm-generic/memory_model.h>
+#ifdef CONFIG_X86
+#include <asm/page_types.h>
+#endif
+#include <asm/page.h>
+
+extern int release_reserved_resource(resource_size_t start, resource_size_t end,
+		unsigned long flags, bool first_lvl);
+
+static unsigned long memblock_addrs_inlap(phys_addr_t base1, phys_addr_t size1,
+		phys_addr_t base2, phys_addr_t size2)
+{
+	return (base1 + size1) <= (base2 + size2) && base1 >= base2;
+}
+
+static bool memblock_inlaps_region(struct memblock_type *type,
+		phys_addr_t base, phys_addr_t size)
+{
+	unsigned long i;
+
+	for (i = 0; i < type->cnt; i++)
+		if (memblock_addrs_inlap(base, size, type->regions[i].base,
+					type->regions[i].size))
+			break;
+	return i < type->cnt;
+}
+
+static bool memblock_in_region_reserved(phys_addr_t base, phys_addr_t size)
+{
+	size = min(size, (phys_addr_t)ULLONG_MAX - base);
+	return memblock_inlaps_region(&memblock.reserved, base, size);
+}
+
+int free_reserved_mm(unsigned long resv_start, unsigned long resv_size)
+{
+	unsigned long pfn_start_align, pfn_end_align;
+	void *start, *end;
+
+	pfn_start_align = PFN_UP(resv_start);
+	pfn_end_align = PFN_DOWN(resv_start + resv_size);
+
+#ifdef CONFIG_X86
+	if (!pfn_range_is_mapped(pfn_start_align, pfn_end_align)) {
+		pr_warn("[0x%lx, 0x%lx] is not mapped\n",
+			pfn_start_align << PAGE_SHIFT,
+			pfn_end_align << PAGE_SHIFT);
+		return -EINVAL;
+	}
+#endif
+
+	start = __va(pfn_start_align << PAGE_SHIFT);
+	end = __va(pfn_end_align << PAGE_SHIFT);
+
+	if (!memblock_in_region_reserved(pfn_start_align << PAGE_SHIFT,
+				PAGE_ALIGN(resv_size))) {
+		pr_warn("[0x%lx, 0x%lx] is not all reserved\n",
+				pfn_start_align << PAGE_SHIFT,
+				pfn_end_align << PAGE_SHIFT);
+		return -EINVAL;
+	}
+
+	free_reserved_area(start, end, 0, "reserve free");
+	memblock_free(pfn_start_align << PAGE_SHIFT,
+		(pfn_end_align << PAGE_SHIFT) - (pfn_start_align << PAGE_SHIFT));
+
+	return release_reserved_resource(pfn_start_align << PAGE_SHIFT,
+			(pfn_end_align << PAGE_SHIFT) - 1,
+			IORESOURCE_MEM, false);
+}
+EXPORT_SYMBOL(free_reserved_mm);
\ No newline at end of file