added paging support

18 files changed, 259 insertions, 48 deletions

diff --git a/Makefile b/Makefile
index a52fe12..653b9e9 100644
--- a/Makefile
+++ b/Makefile
@@ -45,7 +45,7 @@ kernel_entry.o: boot/kernel_entry.asm
 
 
 kernel.o: kernel/kernel.c kernel/console.h
-	gcc -ffreestanding -m32 -o $@ -c $< -fno-asynchronous-unwind-tables -O0
+	gcc -ffreestanding -std=gnu99 -m32 -o $@ -c $< -fno-asynchronous-unwind-tables -O0
 
 x86.o: kernel/x86.c 
 	gcc -ffreestanding -m32 -o $@ -c $< -fno-asynchronous-unwind-tables -O0
@@ -54,10 +54,10 @@ floppy.o: kernel/floppy.c
 	gcc -ffreestanding -m32 -o $@ -c $< -fno-asynchronous-unwind-tables -O0
 
 vmem.o: kernel/vmem.c 
-	gcc -ffreestanding -m32 -o $@ -c $< -fno-asynchronous-unwind-tables -O0
+	gcc -ffreestanding  -std=gnu99 -m32 -o $@ -c $< -fno-asynchronous-unwind-tables -O0
 
 mem.o: kernel/mem.c 
-	gcc -ffreestanding -m32 -o $@ -c $< -fno-asynchronous-unwind-tables -O0
+	gcc -ffreestanding --std=gnu99  -m32 -o $@ -c $< -fno-asynchronous-unwind-tables -O0
 
 e1000.o: kernel/e1000.c
 	gcc -ffreestanding -m32 -o $@ -c $< -fno-asynchronous-unwind-tables -O0
diff --git a/README.md b/README.md
index db8e7c4..fb9f34c 100644
--- a/README.md
+++ b/README.md
@@ -24,12 +24,15 @@ LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 SOFTWARE.
 
+Notes
+-----
+
 Features
 --------
 
 All features are only very rudiemntary and buggy.
 
-* Runs in bochs (with cirrus) and virtual box.
+* Runs in bochs (with cirrus), qemu and virtual box (disable nested paging etc)
 * PIT support / Timing
 * PIC support & Interrupt handling framework
 * PCI bus scanning
@@ -79,6 +82,7 @@ FLOPPY IMAGE
 
 RAM
 ---
+
 0x1000
     boot loader puts the kernel binary here.
 
@@ -105,6 +109,8 @@ RAM
 0xb000 
     memory above this is used for dma (by our floppy.c driver)
 
+0x9000
+    esp
 
 
 REFERENCES
diff --git a/bochsrc b/bochsrc
index 0f8a75b..94f0f4a 100644
--- a/bochsrc
+++ b/bochsrc
@@ -220,7 +220,7 @@ romimage: file=/home/miguel/opt/bochs-2.6.6/bios/BIOS-bochs-latest
 # used all allocated host memory and wants more.
 #
 #=======================================================================
-memory: guest=1024, host=1024
+memory: guest=16, host=1024
 
 #=======================================================================
 # OPTROMIMAGE[1-4]:
diff --git a/boot/mbr.asm b/boot/mbr.asm
index 4dd82d1..96fc788 100644
--- a/boot/mbr.asm
+++ b/boot/mbr.asm
@@ -49,6 +49,7 @@ MEMMAP_OFFSET equ 0x7c00+0x400
 VESA_MODES equ 0x8300
 VESA_MODE_INFO equ 0x8400
 VESA_MODE_SELECT equ 0x4114
+;VESA_MODE_SELECT equ 0x0
 
 jmp boot_16 ;start boot process
 
@@ -62,7 +63,7 @@ VESA_CHECK1:
 VESA_CHECK2:
     db " V2",0
 VESA_CHECK3:
-    db " V2",0
+    db " V3",0
 CHECK_A20:
     db " A20",0
 
@@ -117,7 +118,7 @@ boot_16:
     
 a20check:
 
-    mov bx, STR_VERSION
+    mov bx, CHECK_A20
     call print_string
 
     call check_a20
diff --git a/boot/vesa_setup_16.asm b/boot/vesa_setup_16.asm
index 4f276b5..7180252 100644
--- a/boot/vesa_setup_16.asm
+++ b/boot/vesa_setup_16.asm
@@ -17,6 +17,7 @@ VesaSetup:
     vesa_ok:
     ;
 
+
     ;VESA: get vesa info on mode of interest
     mov ax,0	; set target address in es:di (0:offset)
     mov es,ax
@@ -32,6 +33,7 @@ VesaSetup:
     jmp vesa_err2
     vesa_ok2:
 
+
     ;VESA: finally switch to the mode of choice!
     mov ax,0x4f02   ;vesa function: Set Mode
     mov bx,VESA_MODE_SELECT 
diff --git a/kernel/console.c b/kernel/console.c
index b1a9125..72ad066 100644
--- a/kernel/console.c
+++ b/kernel/console.c
@@ -1,6 +1,7 @@
 #include "console.h"
 
-#define FOOLOS_CONSOLE
+//#define FOOLOS_CONSOLE
+//#undef FOOLOS_CONSOLE
 
 static int posx=0;
 static int posy=0;
diff --git a/kernel/interrupts.c b/kernel/interrupts.c
index 167f0ad..348972e 100644
--- a/kernel/interrupts.c
+++ b/kernel/interrupts.c
@@ -51,8 +51,6 @@ void int_def_handler()
     int_unhandled++;
 
     X86_IRQ_END
-
-
 }
 
 //set a handler for a specific interrupt
@@ -79,7 +77,7 @@ void int_init(uint16_t sel)
 	int_install_ir(i, 0b10001110, sel,&int_def_handler);
     }
 
-    log(FOOLOS_MODULE_NAME,FOOLOS_LOG_INFO,"initializing...");
+    log(FOOLOS_MODULE_NAME,FOOLOS_LOG_INFO,"initializing. IDT: 0x%08x, IDTD: 0x%08X",&idt,&idtd);
 }
 
 void int_install()
diff --git a/kernel/kernel.c b/kernel/kernel.c
index 7d9b848..2dd57fd 100644
--- a/kernel/kernel.c
+++ b/kernel/kernel.c
@@ -25,13 +25,14 @@ void int_test_handler_worker()
 {
     // this can not be called directly from interrupt handler
     // due to optional parameters (...)  probably!
-   log(FOOLOS_MODULE_NAME,FOOLOS_LOG_INFO,"irq 88");
+   panic(FOOLOS_MODULE_NAME,"unhandled EXCEPTION!");
 }
 void int_test_handler()
 {
     X86_IRQ_BEGIN
     int_test_handler_worker();
     sleep(30);
+    while(1); // hang!
     X86_IRQ_END
 }
 
@@ -55,17 +56,23 @@ void kernel_main()
     //	while the last one is set in the Makefile. The font binary
     //	is integrated in the kernel image.
     //
-    vesa_init(0x8300,0x8400,0x7200);
+    //  this function returns the physical base address of 
+    //  our video memory 
+    //
+    uint32_t vesa_physbase=vesa_init(0x8300,0x8400,0x7200);
 
     //
     // PIT config (timer)
     timer_init();
+  
 
     // we know that here, the bootloader placed the mamory map!
     mem_init(0x7c00+0x400,*((uint16_t *)(0x7c00+0x600)));
     
-    // paging  (Todo)
-    vmem_init();
+    // paging  (pass the vesa physbase address for identity mapping)
+    vmem_init(vesa_physbase);
+
+    //
 
     // init and interrupt decriptor table 
     int_init(0x08);
@@ -90,10 +97,15 @@ void kernel_main()
 
     // install test software interrupt handler
     int_install_ir(88, 0b10001110, 0x08,&int_test_handler);
+    
+    for(int i=0;i<19;i++)
+	int_install_ir(i, 0b10001110, 0x08,&int_test_handler);
 
     // now we can enable interrupts back again
     int_enable();
 
+//    int x=10/0;
+
     // pci
     pci_init();
 
@@ -116,6 +128,15 @@ void kernel_main()
    log(FOOLOS_MODULE_NAME,FOOLOS_LOG_INFO,"test mem %x",*(memtest2+1));
    */
 
+    /* stack pointer test?
+   uint32_t *esp=0x90000;
+   for(int i=0;i<10;i++)
+   {
+    log(FOOLOS_MODULE_NAME,FOOLOS_LOG_INFO,"esp: %x",*esp);
+    esp--;
+   }
+   */
+
 
 
     while(1); // never ending loop
diff --git a/kernel/keyboard.c b/kernel/keyboard.c
index ede71a2..7b08098 100644
--- a/kernel/keyboard.c
+++ b/kernel/keyboard.c
@@ -1,18 +1,15 @@
 #include "kernel.h"
 #include "x86.h"
 #include "console.h"
+
 #include "../lib/logger/log.h"	// logger facilities
 #define FOOLOS_MODULE_NAME "keyboard"
 
 /// keyboard driver ////
 
-
-//static int cursor=0;
-//static char last_code=0;
-
 void keyboard_handle(uint8_t in)
 {
-   log(FOOLOS_MODULE_NAME,FOOLOS_LOG_INFO,"scancode 0x%x",in);
+   log(FOOLOS_MODULE_NAME,FOOLOS_LOG_FINE,"scancode 0x%x",in);
 
     int i=0;
     //
diff --git a/kernel/mem.c b/kernel/mem.c
index b761c8c..4896272 100644
--- a/kernel/mem.c
+++ b/kernel/mem.c
@@ -38,6 +38,39 @@ int  mmap_test(int bit)
      return _mmngr_memory_map[bit / 32] &  (1 << (bit % 32));
 }
 
+void mmap_show_free ()
+{
+
+    int last_pos=0; 
+    uint32_t last=_mmngr_memory_map[0];
+
+    for (int i=1; i< MEM_BITMAP_SIZE ; i++)
+    {
+	if (_mmngr_memory_map[i] != last||i==MEM_BITMAP_SIZE-1)
+	{
+
+	    if(last==0)
+	    {
+		log(FOOLOS_MODULE_NAME,FOOLOS_LOG_INFO,"%d -%d free",last_pos*32,i*32);
+	    }
+	    else if(last==0xffffffff)
+	    {
+		log(FOOLOS_MODULE_NAME,FOOLOS_LOG_INFO,"%d -%d full",last_pos*32,i*32);
+	    }
+	    else
+	    {
+		log(FOOLOS_MODULE_NAME,FOOLOS_LOG_INFO,"%d -%d some free",last_pos*32,i*32);
+	    }
+
+	   last_pos=i;
+	   last=_mmngr_memory_map[i];
+
+
+	}
+    }
+
+}
+
 //
 int mmap_first_free () 
 {
@@ -61,6 +94,7 @@ int mmap_first_free ()
 
 }
 
+
 void pmmngr_init () 
 {
     //! By default, all of memory is in use
@@ -107,7 +141,7 @@ void* pmmngr_alloc_block ()
  
     if (frame == -1)
     {
-	scr_put_string_nl("OUT OF MEM!");
+	log(FOOLOS_MODULE_NAME,FOOLOS_LOG_INFO,"OUT OF MEMORY");
 	return 0;	//out of memory
     }
 
@@ -231,7 +265,7 @@ void mem_init(uint16_t *memmap,uint16_t entries)
 
 
 #ifdef MEM_PRINT_MEMORYMAP
-	log(FOOLOS_MODULE_NAME,FOOLOS_LOG_INFO,"%x : 0x%08x - 0x%08x",
+	log(FOOLOS_MODULE_NAME,FOOLOS_LOG_INFO,"type: %02d / range:  0x%08x - 0x%08x",
 		memmap[8], 
 		(((uint32_t)memmap[1])<<16)+memmap[0],
 		(((uint32_t)memmap[1])<<16)+memmap[0]
@@ -249,7 +283,7 @@ void mem_init(uint16_t *memmap,uint16_t entries)
 	
     }
 
-    log(FOOLOS_MODULE_NAME,FOOLOS_LOG_INFO,"Available Mem: %d bytes.",avail_mem);
+    log(FOOLOS_MODULE_NAME,FOOLOS_LOG_INFO,"Available Mem: %d bytes. (~%d MB)",avail_mem,avail_mem/1024/1024);
     log(FOOLOS_MODULE_NAME,FOOLOS_LOG_INFO,"Available 4K blocks: %d blocks.",mem_free_blocks);
 
 }
diff --git a/kernel/pci.c b/kernel/pci.c
index c8bd95d..c1e6753 100644
--- a/kernel/pci.c
+++ b/kernel/pci.c
@@ -85,11 +85,11 @@ uint16_t pciCheck(uint8_t bus, uint8_t slot)
 	    {
 	//	uint16_t irq=pciConfigReadWord(bus,slot,0,0x3C);
 	//	uint16_t irq2=pciConfigReadWord(bus,slot,0,0x3E);
-		init_e1000();
+//		init_e1000();
 
-		test_bar(bus,slot,0x10);
-		test_bar(bus,slot,0x14);
-		test_bar(bus,slot,0x18);
+//		test_bar(bus,slot,0x10);
+//		test_bar(bus,slot,0x14);
+//		test_bar(bus,slot,0x18);
 
 	//	scr_put_hex(irq);
 	//	scr_put_hex(irq2);
diff --git a/kernel/shell.c b/kernel/shell.c
index 45e8620..aff2dc4 100644
--- a/kernel/shell.c
+++ b/kernel/shell.c
@@ -20,7 +20,7 @@ void shell_init()
 
 void shell_put(char x)
 {
-    log(FOOLOS_MODULE_NAME,FOOLOS_LOG_INFO,"char:%c",x);
+    log(FOOLOS_MODULE_NAME,FOOLOS_LOG_DEBUG,"char:%c",x);
 
     if(pos<COMMAND_LENGTH-2);
 
@@ -65,6 +65,15 @@ void shell_execute()
     {
 	int_generate88();
     }
+    else if(1==strcmp(command,"MEM"))
+    {
+	mmap_show_free();	
+    }
+    else if(1==strcmp(command,"ALLOC"))
+    {
+	uint32_t *malloc= pmmngr_alloc_block();
+	log(FOOLOS_MODULE_NAME,FOOLOS_LOG_INFO,"allocated 4KB block at: %08x.",malloc);
+    }
     else if(1==strcmp(command,"READ"))
     {
 	uint8_t *read= flpydsk_read_sector (10);
diff --git a/kernel/vesa.c b/kernel/vesa.c
index 048dbf1..b7b4615 100644
--- a/kernel/vesa.c
+++ b/kernel/vesa.c
@@ -57,7 +57,7 @@ static console_y;
 static console_lines;
 static console_cols;
 
-void vesa_init(vbeinfo *info,vbemodeinfo *mode,foolfont *rawfont)
+uint32_t vesa_init(vbeinfo *info,vbemodeinfo *mode,foolfont *rawfont)
 {
     //the only functionallu important init lines! (rest is log)
     VbeModeInfoBlock=mode;
@@ -90,10 +90,13 @@ void vesa_init(vbeinfo *info,vbemodeinfo *mode,foolfont *rawfont)
     while(*modeptr!=0xffff&&*modeptr!=0)
     {
 	log(FOOLOS_MODULE_NAME,FOOLOS_LOG_DEBUG,"mode supported : 0x%x", (*modeptr));
+	scr_put_hex(*modeptr);
 	modeptr++;
     }
 #endif
 
+    return VbeModeInfoBlock->physbase;   
+
 }
 
 void PutPixel(int x,int y, int color){
diff --git a/kernel/vmem.c b/kernel/vmem.c
index 9d34810..b1ecfa1 100644
--- a/kernel/vmem.c
+++ b/kernel/vmem.c
@@ -1,5 +1,12 @@
+// http://www.brokenthorn.com/Resources/OSDev18.html
+
 #include "kernel.h"
+#include "x86.h"
+#include "../lib/logger/log.h"	// logger facilities
+#define FOOLOS_MODULE_NAME "vmem"
+
 
+// TODO : why is the frame not 0xfffff??
 enum PAGE_PTE_FLAGS {
  
     I86_PTE_PRESENT		=	1,		//0000000000000000000000000000001
@@ -12,7 +19,7 @@ enum PAGE_PTE_FLAGS {
     I86_PTE_PAT			=	0x80,		//0000000000000000000000010000000
     I86_PTE_CPU_GLOBAL		=	0x100,		//0000000000000000000000100000000
     I86_PTE_LV4_GLOBAL		=	0x200,		//0000000000000000000001000000000
-    I86_PTE_FRAME		=	0x7FFFF000 	//1111111111111111111000000000000
+    I86_PTE_FRAME		=	0xFFFFF000 	//1111111111111111111000000000000
 };
 
 enum PAGE_PDE_FLAGS {
@@ -27,7 +34,7 @@ enum PAGE_PDE_FLAGS {
     I86_PDE_4MB			=	0x80,		//0000000000000000000000010000000
     I86_PDE_CPU_GLOBAL		=	0x100,		//0000000000000000000000100000000
     I86_PDE_LV4_GLOBAL		=	0x200,		//0000000000000000000001000000000
-    I86_PDE_FRAME		=	0x7FFFF000 	//1111111111111111111000000000000
+    I86_PDE_FRAME		=	0xFFFFF000 	//1111111111111111111000000000000
 };
 
 //! page table entry
@@ -62,53 +69,65 @@ typedef uint8_t bool;
 #define PAGE_SIZE 4096
  
 //! page table
-struct ptable {
+typedef struct ptable_struct {
  
     pt_entry m_entries[PAGES_PER_TABLE];
-};
+}ptable ;
  
 //! page directory
-struct pdirectory {
+typedef struct pdirectory_struct {
  
     pd_entry m_entries[PAGES_PER_DIR];
-};
+}pdirectory;
 
-void 		pt_entry_add_attrib (pt_entry* e, uint32_t attrib)
+void pt_entry_add_attrib (pt_entry* e, uint32_t attrib)
 {
+    *e|=attrib;
 }
-void 		pt_entry_del_attrib (pt_entry* e, uint32_t attrib)
+void pt_entry_del_attrib (pt_entry* e, uint32_t attrib)
 {
+    *e&=~attrib;
 }
-void 		pt_entry_set_frame (pt_entry* e , physical_addr addr)
+void pt_entry_set_frame (pt_entry* e , physical_addr addr)
 {
+     //          *e = (*e & ~I86_PTE_FRAME) | addr;                               
+
+    *e|=I86_PTE_FRAME&addr;
+
 }
-bool 		pt_entry_is_present (pt_entry e)
+bool pt_entry_is_present (pt_entry e)
 {
-    return 1;
+    return e&I86_PTE_PRESENT;
 }
-bool 		pt_entry_is_writable (pt_entry e)
+
+bool pt_entry_is_writable (pt_entry e)
 {
-    return 1;
+    return e&I86_PTE_WRITABLE;
 }
-physical_addr	pt_entry_pfn (pt_entry e)
+
+physical_addr pt_entry_pfn (pt_entry e)
 {
-    return 1;
+    return e&I86_PTE_FRAME;
 }
 
 void		pd_entry_add_attrib (pd_entry* e, uint32_t attrib)
 {
+    *e|=attrib;
 }
 
 void		pd_entry_del_attrib (pd_entry* e, uint32_t attrib)
 {
+    *e&=~attrib;
 }
 void		pd_entry_set_frame (pd_entry* e, physical_addr add)
 {
+    *e|=I86_PDE_FRAME&add;
 }
 bool		pd_entry_is_present (pd_entry e)
 {
-    return 1;
+    return e&I86_PDE_PRESENT;
 }
+/*
 bool		pd_entry_is_user (pd_entry e)
 {
     return 1;
@@ -118,20 +137,23 @@ bool		pd_entry_is_4mb (pd_entry e)
 {
     return 1;
 }
+*/
 
 bool		pd_entry_is_writable (pd_entry e)
 {
-    return 1;
+    return e&I86_PDE_WRITABLE;
 }
 
 physical_addr	pd_entry_pfn (pd_entry e)
 {
-    return 1;
+    return e&I86_PDE_FRAME;
 }
 
+/*
 void		pd_entry_enable_global (pd_entry e)
 {
 }
+*/
 
 uint8_t vmmngr_alloc_page (pt_entry* e) 
 {
@@ -148,8 +170,94 @@ uint8_t vmmngr_alloc_page (pt_entry* e)
 	return 1;
 }
 
-void vmem_init()
+void vmmngr_free_page (pt_entry* e) 
+{
+    void* p = (void*)pt_entry_pfn (*e);
+    if (p)
+	pmmngr_free_block (p);
+ 
+    pt_entry_del_attrib (e, I86_PTE_PRESENT);
+}
+
+pt_entry* vmmngr_ptable_lookup_entry (ptable* p, virtual_addr addr) 
+{
+ 
+    if (p)
+	return &p->m_entries[ PAGE_TABLE_INDEX (addr) ];
+
+    return 0;
+}
+
+// TODO !?  http://www.brokenthorn.com/Resources/OSDev18.html
+void vmmngr_map_page (void* phys, void* virt) 
+{
+
+}
+
+void vmem_init(uint32_t vesa_physbase)
 {
+    log(FOOLOS_MODULE_NAME,FOOLOS_LOG_INFO,"init paging (vesa base: 0x%08x)",vesa_physbase);
+
+    ptable* table1 = (ptable*) pmmngr_alloc_block ();
+
+    if (!table1)panic(FOOLOS_MODULE_NAME,"unable to alloc table1");
+    log(FOOLOS_MODULE_NAME,FOOLOS_LOG_INFO,"table1: 0x%X",table1);
+ 
+    ptable* table2 = (ptable*) pmmngr_alloc_block ();
+
+    if (!table1)panic(FOOLOS_MODULE_NAME,"unable to alloc table2");
+    log(FOOLOS_MODULE_NAME,FOOLOS_LOG_INFO,"table2: 0x%X",table2);
+
+    // TODO: 3blocks? 
+    pdirectory*	dir = (pdirectory*) pmmngr_alloc_block ();
+    if (!dir)panic(FOOLOS_MODULE_NAME,"unable to alloc pdirectory");
+    log(FOOLOS_MODULE_NAME,FOOLOS_LOG_INFO,"pdirectory: 0x%X",dir);
+
+    //! map 1mb to 3gb (where we are at)
+    for (int i=0, frame=vesa_physbase, virt=vesa_physbase; i<1024; i++, frame+=4096, virt+=4096) {
+
+	//! create a new page
+	pt_entry page=0;
+	pt_entry_add_attrib (&page, I86_PTE_PRESENT);
+	pt_entry_set_frame (&page, frame);
+
+	//! ...and add it to the page table
+	table1->m_entries [PAGE_TABLE_INDEX (virt) ] = page;
+    }
+
+    //! 1st 4mb are idenitity mapped
+    for (int i=0, frame=0x0, virt=0x00000000; i<1024; i++, frame+=4096, virt+=4096) 
+    {
+
+	//! create a new page
+	pt_entry page=0;
+	pt_entry_add_attrib (&page, I86_PTE_PRESENT);
+	pt_entry_set_frame (&page, frame);
+
+	//! ...and add it to the page table
+	table2->m_entries [PAGE_TABLE_INDEX (virt) ] = page;
+    }
+
+   
+    pd_entry* entry = &dir->m_entries [PAGE_DIRECTORY_INDEX (vesa_physbase) ];
+    *entry=0;
+    pd_entry_add_attrib (entry, I86_PDE_PRESENT);
+    pd_entry_add_attrib (entry, I86_PDE_WRITABLE);
+    pd_entry_set_frame (entry, (physical_addr)table1);
+    
+
+    pd_entry* entry2 = &dir->m_entries [PAGE_DIRECTORY_INDEX (0x00000000) ];
+    *entry2=0;
+    pd_entry_add_attrib (entry2, I86_PDE_PRESENT);
+    pd_entry_add_attrib (entry2, I86_PDE_WRITABLE);
+    pd_entry_set_frame (entry2, (physical_addr)table2);
+
+
+    x86_set_pdbr(dir);
+
+    log(FOOLOS_MODULE_NAME,FOOLOS_LOG_INFO,"enabling paging...");
+    x86_paging_enable();
+
 
 }
 
diff --git a/kernel/x86.c b/kernel/x86.c
index ee38599..cc7c303 100644
--- a/kernel/x86.c
+++ b/kernel/x86.c
@@ -36,3 +36,17 @@ uint32_t x86_inl(int port)
     return data;
 }
 
+
+void x86_set_pdbr(uint32_t addr) 
+{
+    asm volatile("mov %0, %%cr3":: "b"(addr));
+
+}
+
+void x86_paging_enable()
+{
+    unsigned int cr0;
+    asm volatile("mov %%cr0, %0": "=b"(cr0));
+    cr0 |= 0x80000000;
+    asm volatile("mov %0, %%cr0":: "b"(cr0));
+}
diff --git a/kernel/x86.h b/kernel/x86.h
index 2b7572c..3233124 100644
--- a/kernel/x86.h
+++ b/kernel/x86.h
@@ -16,5 +16,7 @@ void x86_outw(int port, uint16_t data);
 uint16_t x86_inw(int port);
 void x86_outl(int port, uint32_t data);
 uint32_t x86_inl(int port);
+void x86_set_pdbr(uint32_t addr);
+void x86_paging_enable();
 
 #endif
diff --git a/lib/logger/log.c b/lib/logger/log.c
index 3a6606e..fd226e5 100644
--- a/lib/logger/log.c
+++ b/lib/logger/log.c
@@ -19,3 +19,17 @@ void log(char *module_name, int log_level, char *format_string, ...)
 
     
 }
+void panic(char *module_name,  char *format_string)
+{
+
+    PutConsole("!! KERNEL PANIC !! ",0b1111100000000000,0);
+    PutConsole(module_name,0b1111100000000000,0);
+    PutConsole(" : ",0b0000011111100000,0);
+    PutConsole(format_string,0b1111100000000000,0);
+
+
+    while(1); // halt
+
+
+    
+}
diff --git a/lib/logger/log.h b/lib/logger/log.h
index 9c32a39..251c66f 100644
--- a/lib/logger/log.h
+++ b/lib/logger/log.h
@@ -6,6 +6,7 @@
 #define FOOLOS_LOG_FINE 1
 
 void log(char *module_name, int prio, char *format_string, ...);
+void panic(char *module_name, char *format_string);
 
 #endif