kmalloc returns aligned memory

src/arch/x86/kmem.cpp

@@ -84,6 +84,15 @@ struct HeapEntry *split_entry(struct HeapEntry *what, size_t n) {
 
 void *kmalloc(size_t n) {
     assert(initialized);
+
+    if ((n & 0xFULL) != 0) {
+        size_t origN = n;
+        n += 15;
+        n &= ~0xFULL;
+        assert(n > origN);
+    }
+    assert((n & 0xFULL) == 0);
+
     struct HeapEntry *res = NULL;
     {
         LockGuard l(kmem_lock);
@@ -182,6 +191,8 @@ void *kmalloc(size_t n) {
         res->prev = NULL;
         res->magic = KERN_HeapMagicTaken;
     }
+    assert((((uintptr_t) res->data) & 0xFULL) == 0);
+
     for (size_t i = 0; i < n; i++) res->data[i] = 0xFEU;
     used.fetch_add(n);
     return res->data;

src/arch/x86/kmem.hpp

@@ -15,8 +15,8 @@ struct HeapEntry {
     struct HeapEntry *next;
     struct HeapEntry *prev;
     uint64_t len;
-    char data[];
-};
+    char data[] __attribute__((aligned(16)));
+} __attribute__((packed, aligned(32)));
 
 extern struct HeapEntry *KERN_HeapBegin;
 extern uintptr_t KERN_HeapEnd;// Past the end

src/arch/x86/task.cpp

@@ -182,6 +182,8 @@ struct Task *new_ktask(void (*fn)(), const char *name) {
     strcpy(name, newt->name);
 
     newt->frame.sp = ((((uintptr_t) newt->stack) + TASK_SS - 1) & (~0xFULL));// Ensure 16byte alignment
+    assert((newt->frame.sp & 0xFULL) == 0);
+
     newt->frame.ip = (uint64_t) fn;
     newt->frame.cs = GDTSEL(gdt_code);
     newt->frame.ss = GDTSEL(gdt_data);