diff --git a/arch/x86/kernel/apic.c b/arch/x86/kernel/apic.c
index 0f0ee985..29033d0e 100644
--- a/arch/x86/kernel/apic.c
+++ b/arch/x86/kernel/apic.c
@@ -327,18 +327,23 @@ void smp_start(uint32_t id)
 }
 #endif
 
-static unsigned int* search_apic(unsigned int base, unsigned int limit) {
-	uint32_t* ptr;
+#if 1
+static apic_mp_t* search_apic(size_t base, size_t limit) {
+	size_t ptr;
+	apic_mp_t* tmp;
 
-	for (ptr = (uint32_t*) base; (uint32_t) ptr < limit; ptr++) {
-		if (*ptr == MP_FLT_SIGNATURE) {
-			if (!(((apic_mp_t*)ptr)->version > 4) && ((apic_mp_t*)ptr)->features[0])
-				return ptr;
-		}
+	for (ptr=base; ptr<=limit-sizeof(uint32_t); ptr++) {
+		tmp = (apic_mp_t*) ptr;
+
+		if (tmp->signature == MP_FLT_SIGNATURE) {
+			if (!((tmp->version > 4) || tmp->features[0]))
+				return tmp;
         }
+	}
 
 	return NULL;
 }
+#endif
 
 #if MAX_CORES > 1
 int smp_init(void)
@@ -362,7 +367,7 @@ int smp_init(void)
 		 */
 		bootaddr = (char*) SMP_SETUP_ADDR;
 		memcpy(bootaddr, boot_code, sizeof(boot_code));
-		for(j=0; j<sizeof(boot_code)-sizeof(uint32_t); j++)
+		for(j=0; j<=sizeof(boot_code)-sizeof(uint32_t); j++)
 		{
 			// replace 0xDEADC0DE with the address of the smp entry code
 			if (*((uint32_t*) (bootaddr+j)) == 0xDEADC0DE) {
@@ -559,15 +564,15 @@ static int apic_probe(void)
 	uint32_t i, count;
 	int isa_bus = -1;
 
-	apic_mp = (apic_mp_t*) search_apic(0xF0000, 0x100000);
+#if 1
+	apic_mp = search_apic(0xF0000, 0x100000);
 	if (apic_mp)
 		goto found_mp;
-	apic_mp = (apic_mp_t*) search_apic(0x9F000, 0xA0000);
+	apic_mp = search_apic(0x9F000, 0xA0000);
 	if (apic_mp)
 		goto found_mp;
-
+#else
 	// searching MP signature in the reserved memory areas
-#ifdef CONFIG_MULTIBOOT
 	if (mb_info && (mb_info->flags & MULTIBOOT_INFO_MEM_MAP)) {
  		multiboot_memory_map_t* mmap = (multiboot_memory_map_t*) mb_info->mmap_addr;
 		multiboot_memory_map_t* mmap_end = (void*) ((size_t) mb_info->mmap_addr + mb_info->mmap_length);
@@ -576,10 +581,19 @@ static int apic_probe(void)
 			if (mmap->type == MULTIBOOT_MEMORY_RESERVED) {
 				addr = mmap->addr;
 
-				for(i=0; i<mmap->len-sizeof(uint32_t); i++, addr++) {
+				/*
+				 * MultiProcessor Specification 1.4:
+				 * =================================
+				 * The following is a list of the suggested memory spaces for the MP configuration table:
+				 * a. In the first kilobyte of Extended BIOS Data Area (EBDA), or
+				 * b. Within the last kilobyte of system base memory if the EBDA segment is undefined, or
+				 * c. At the top of system physical memory, or
+				 * d. In the BIOS read-only memory space between 0E0000h and 0FFFFFh.
+				 */
+				for(i=0; (i<mmap->len-sizeof(uint32_t)) && (addr < 0x0FFFFF); i++, addr++) {
 					if (*((uint32_t*) addr) == MP_FLT_SIGNATURE) {
 						apic_mp = (apic_mp_t*) addr;
-						if (!(apic_mp->version > 4) && apic_mp->features[0])
+						if (!((apic_mp->version > 4) || apic_mp->features[0]))
 							goto found_mp;
 					}
 				}
@@ -593,6 +607,7 @@ found_mp:
 	if (!apic_mp) 
 		goto no_mp;
 
+	kprintf("Found MP config table at 0x%x\n", apic_mp);
 	kprintf("System uses Multiprocessing Specification 1.%u\n", apic_mp->version);	
 	kprintf("MP features 1: %u\n", apic_mp->features[0]);
 
diff --git a/arch/x86/kernel/entry.asm b/arch/x86/kernel/entry.asm
index e2e2d84a..8fd0e8c3 100644
--- a/arch/x86/kernel/entry.asm
+++ b/arch/x86/kernel/entry.asm
@@ -440,10 +440,10 @@ extern syscall_handler
 
 ; used to realize system calls
 isrsyscall:
-    ;push ds
-    ;push fs
-    ;push gs
-    ;push es
+    push ds
+    push fs
+    push gs
+    push es
     push ebp
     push edi
     push esi
@@ -460,10 +460,10 @@ isrsyscall:
     pop esi
     pop edi
     pop ebp
-    ;pop es
-    ;pop gs
-    ;pop fs
-    ;pop ds
+    pop es
+    pop gs
+    pop fs
+    pop ds
     iret
 
 global irq0