Implement interrupts

kernel/hal/x86_64/cpu.c

@@ -0,0 +1,14 @@
+#include <stdint.h>
+#include <stddef.h>
+
+uint64_t cpu_rdmsr(uint32_t id) {
+  uint32_t lo, hi;
+  asm volatile("rdmsr" : "=m"(lo), "=d"(hi) : "c"(id));
+  return ((uint64_t)lo) | ((uint64_t)hi << 32);
+}
+
+uint64_t cpu_wrmsr(uint32_t id, uint64_t val) {
+  uint32_t lo = val & 0xffffffff, hi = (val >> 32) & 0xffffffff;
+  asm volatile("wrmsr" :: "a"(lo), "d"(hi), "c"(id) : "memory");
+  return val;
+}