diff --git a/hermit/arch/x86/kernel/gdt.c b/hermit/arch/x86/kernel/gdt.c
index 40ead0a3b..6d73aaeba 100644
--- a/hermit/arch/x86/kernel/gdt.c
+++ b/hermit/arch/x86/kernel/gdt.c
@@ -142,7 +142,7 @@ void gdt_install(void)
 	 * Create TSS for each task at ring0 (we use these segments for task switching)
 	 */
 	for(i=0; i<MAX_CORES; i++) {
-		task_state_segments[i].rsp0 = (size_t) &boot_stack + (i + 1) * KERNEL_STACK_SIZE - 16;
+		task_state_segments[i].rsp0 = (size_t) &boot_stack + i * KERNEL_STACK_SIZE - 0x10;
 		gdt_set_gate(num+i*2, (unsigned long) (task_state_segments+i), sizeof(tss_t)-1,
 			GDT_FLAG_PRESENT | GDT_FLAG_TSS | GDT_FLAG_RING0, gran_ds);
 	}