完善代码

13186379707 · Dec 18, 2023 · 5bcbab6 · 5bcbab6
1 parent e76f052
commit 5bcbab6
Showing 1 changed file with 3 additions and 1 deletion.
diff --git a/eBPF_Supermarket/kvm_watcher/include/kvm_vcpu.h b/eBPF_Supermarket/kvm_watcher/include/kvm_vcpu.h
@@ -89,8 +89,10 @@ static int trace_mark_page_dirty_in_slot(struct kvm *kvm,
                                          gfn_t gfn, void *rb, pid_t vm_pid) {
     CHECK_PID(vm_pid) {
         u32 flags;
+        struct kvm_memory_slot *slot;
+        bpf_probe_read_kernel(&slot, sizeof(memslot), &memslot);
         bpf_probe_read_kernel(&flags, sizeof(memslot->flags), &memslot->flags);
-        if (flags & KVM_MEM_LOG_DIRTY_PAGES) {  // 检查memslot是否启用了脏页追踪
+        if (slot && (flags & KVM_MEM_LOG_DIRTY_PAGES)) {  // 检查memslot是否启用了脏页追踪
             gfn_t gfnum = gfn;
             u32 *count = bpf_map_lookup_elem(&count_dirty_map, &gfnum);
             if (count) {