Free to our CPU's slab, not to CPU 0's slab

Previously, ksfree passed the whole CPU array for a slab to kfree_pool, which expected a pointer to the specific kmem to free to. Since the array decayed to a pointer, this compiled and worked, but would always free to CPU 0's slab.

Free to our CPU's slab, not to CPU 0's slab
bc0ff894 · Austin Clements · 8ff159ab · bc0ff894
--- a/kernel/kalloc.cc
+++ b/kernel/kalloc.cc
@@ -321,5 +321,5 @@ kfree(void *v)
 void
 ksfree(int slab, void *v)
 {
-  kfree_pool(slabmem[slab], (char*) v);
+  kfree_pool(&slabmem[slab][mycpuid()], (char*) v);
 }