diff --git a/sortix/Makefile b/sortix/Makefile
index 0d857f91..d196e2d2 100644
--- a/sortix/Makefile
+++ b/sortix/Makefile
@@ -87,6 +87,7 @@ fs/devfs.o \
 fs/initfs.o \
 fs/ramfs.o \
 ../libmaxsi/libmaxsi-sortix.a \
+end.o # Must be last
 
 JSOBJS:=$(subst .o,-js.o,$(OBJS))
 
diff --git a/sortix/end.cpp b/sortix/end.cpp
new file mode 100644
index 00000000..2f620704
--- /dev/null
+++ b/sortix/end.cpp
@@ -0,0 +1,33 @@
+/******************************************************************************
+
+	COPYRIGHT(C) JONAS 'SORTIE' TERMANSEN 2011.
+
+	This file is part of Sortix.
+
+	Sortix 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, either version 3 of the License, or (at your option) any later
+	version.
+
+	Sortix is distributed in the hope that it will be useful, but WITHOUT ANY
+	WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+	FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
+	details.
+
+	You should have received a copy of the GNU General Public License along
+	with Sortix. If not, see <http://www.gnu.org/licenses/>.
+
+	end.cpp
+	Places a symbol at the end of the kernel binary. This allows us to easily
+	detect the size of the kernel. Be sure to put this one last in the linking
+	command.
+
+******************************************************************************/
+
+#include "platform.h"
+
+namespace Sortix
+{
+	size_t end; // Put in the bss, the last segment.
+}
+
diff --git a/sortix/x86-family/memorymanagement.cpp b/sortix/x86-family/memorymanagement.cpp
index a998678d..da684126 100644
--- a/sortix/x86-family/memorymanagement.cpp
+++ b/sortix/x86-family/memorymanagement.cpp
@@ -35,7 +35,7 @@ using namespace Maxsi;
 
 namespace Sortix
 {
-	const addr_t KERNELEND = 0x200000UL;
+	extern size_t end;
 
 	namespace Page
 	{
@@ -57,11 +57,21 @@ namespace Sortix
 
 		void Init(multiboot_info_t* bootinfo)
 		{
+			const size_t MAXKERNELEND = 0x400000UL; /* 4 MiB */
+			addr_t kernelend = Page::AlignUp((addr_t) &end);
+			if ( MAXKERNELEND < kernelend )
+			{
+				Log::PrintF("Warning: The kernel is too big! It ends at 0x%zx, "
+				            "but the highest ending address supported is 0x%zx. "
+				            "The system may not boot correctly.\n", kernelend,
+				            MAXKERNELEND);
+			}
+
 			Page::pagesnotonstack = 0;
 			Page::totalmem = 0;
 
 			// The first mebibytes are reserved for use by the kernel.
-			Page::pagesallocated = KERNELEND >> 12UL;
+			Page::pagesallocated = kernelend >> 12UL;
 
 			if ( !( bootinfo->flags & MULTIBOOT_INFO_MEM_MAP ) )
 			{
@@ -109,7 +119,7 @@ namespace Sortix
 					addr_t highest = regionend;
 
 					// Don't allocate the kernel.
-					if ( lowest < KERNELEND ) { processed = KERNELEND; continue; }
+					if ( lowest < kernelend ) { processed = kernelend; continue; }
 
 					// Don't give any of our modules to the physical page
 					// allocator, we'll need them.