diff --git a/kaleid/kernel/ke/syscall.asm b/kaleid/kernel/ke/syscall.asm
index e761905..28686ea 100644
--- a/kaleid/kernel/ke/syscall.asm
+++ b/kaleid/kernel/ke/syscall.asm
@@ -34,15 +34,15 @@ KeJumpToUserspace:
     ; rsi = entry point in user space
     ; rdx = user space stack
 
-    mov rax, 0x1b ; Selector 0x18 (User Data) + RPL 3
+    mov rax, 0x10 ; Selector 0x10 (User Data) + RPL 3
     mov ds, ax
     mov es, ax
 
 ; Build a fake iret frame
-    push rax          ; Selector 0x18 (User Data) + RPL 3
+    push rax          ; Selector 0x10 (User Data) + RPL 3
     push rdx          ; User space stack
     push 0x202        ; rflags = interrupt enable + reserved bit
-    push 0x23         ; Selector 0x20 (User Code) + RPL 3
+    push 0x10         ; Selector 0x10 (User Code) + RPL 3
     push rsi          ; Entry point in user space
     
     xor rax, rax
diff --git a/kaleid/kernel/mm/gdt.c b/kaleid/kernel/mm/gdt.c
index 2b5d888..ff04d8c 100644
--- a/kaleid/kernel/mm/gdt.c
+++ b/kaleid/kernel/mm/gdt.c
@@ -41,7 +41,7 @@ void MmInitGdt(void)
     memzero((void *)&gdt[0], sizeof(gdt));
     memzero((void *)&tssDesc, sizeof(tssDesc));
     memzero((void *)&tss, sizeof(tss));
-
+    
     // Kernel codeseg
     gdt[1].lowLimit     = 0xFFFF;
     gdt[1].access       = 0x98;
@@ -74,14 +74,14 @@ void MmInitGdt(void)
     memmove(&gdt[3], &tssDesc, sizeof(TssDescriptor_t));
 
     DebugLog("GDT & TSS initialized\n");
-    DebugLog("gdt[0] : %#x\n", &gdt[0]);
-    DebugLog("gdt[1] : %#x\n", &gdt[1]);
-    DebugLog("gdt[2] : %#x\n", &gdt[2]);
-    DebugLog("tss    : %#x\n", &gdt[3]);
-    DebugLog("ist1    : %#x\n", tss.ist1);
-    DebugLog("ist2    : %#x\n", tss.ist2);
-    DebugLog("ist3    : %#x\n", tss.ist3);
-    DebugLog("rsp0    : %#x\n", tss.ist1);
+    DebugLog("gdt[0] : %#b\n", gdt[0]);
+    DebugLog("gdt[1] : %#b\n", gdt[1]);
+    DebugLog("gdt[2] : %#b\n", gdt[2]);
+    DebugLog("tss    : %#b\n", gdt[3]);
+    DebugLog("ist1   : %#p\n", tss.ist1);
+    DebugLog("ist2   : %#p\n", tss.ist2);
+    DebugLog("ist3   : %#p\n", tss.ist3);
+    DebugLog("rsp0   : %#p\n", tss.ist1);
 
     MmLoadGdt(&gdtPtr, tssOffset);
 }
diff --git a/kaleid/kernel/sh/testcmds.c b/kaleid/kernel/sh/testcmds.c
index 102212b..90470b0 100644
--- a/kaleid/kernel/sh/testcmds.c
+++ b/kaleid/kernel/sh/testcmds.c
@@ -30,6 +30,7 @@
 #include <io/vga.h>
 #include <io/spkr.h>
 #include <ke/time.h>
+#include <ke/syscall.h>
 #include <libbuf.h>
 #include <sh/shell.h>
 #include <po/shtdwn.h>
@@ -330,7 +331,41 @@ error_t CmdSyscallTest(int argc, char **argv, char *cmdline)
 
 error_t CmdRing3Test(int argc, char **argv, char *cmdline)
 {
-    // TODO 
+    size_t size = 50*MB;
+    void *entryPoint = (void*)USERSPACE + 51*KB;
+    ulong flags = PRESENT | READWRITE | USERMODE;
+
+    KernLog("Allocating %u o...\n", size);
+    ulong id = MmAllocPageFrame(size, false);
+    KernLog("Allocated with id : %lu\n", id);
+
+    KernLog("Mapping pages id %d at %p (flags %#x)...\n", id, entryPoint, flags);
+    error_t err = MmMapPageFrame(id, entryPoint, flags);
+    if (err == EOK)
+        KernLog("Successfully mapped.\n");
+    else {
+        KernLog("Failed to map !\n");
+        return ENOMEM;
+    }
+    
+    size = 50*KB;
+    void *stackAddr = (void*)USERSPACE;
+    flags = PRESENT | READWRITE | USERMODE;
+
+    KernLog("Allocating %u o...\n", size);
+    id = MmAllocPageFrame(size, false);
+    KernLog("Allocated with id : %lu\n", id);
+
+    KernLog("Mapping pages id %d at %p (flags %#x)...\n", id, stackAddr, flags);
+    err = MmMapPageFrame(id, stackAddr, flags);
+    if (err == EOK)
+        KernLog("Successfully mapped.\n");
+    else {
+        KernLog("Failed to map !\n");
+        return ENOMEM;
+    }
+    
+    KeJumpToUserspace(0, entryPoint, stackAddr);
 
     return EOK;
 }