summary refs log tree commit diff stats
path: root/accel/kvm
diff options
context:
space:
mode:
Diffstat (limited to 'accel/kvm')
-rw-r--r--accel/kvm/kvm-all.c13
1 files changed, 12 insertions, 1 deletions
diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c
index 84c943fcdb..f88a52393f 100644
--- a/accel/kvm/kvm-all.c
+++ b/accel/kvm/kvm-all.c
@@ -598,8 +598,12 @@ static void kvm_memslot_init_dirty_bitmap(KVMSlot *mem)
      * too, in most cases).
      * So for now, let's align to 64 instead of HOST_LONG_BITS here, in
      * a hope that sizeof(long) won't become >8 any time soon.
+     *
+     * Note: the granule of kvm dirty log is qemu_real_host_page_size.
+     * And mem->memory_size is aligned to it (otherwise this mem can't
+     * be registered to KVM).
      */
-    hwaddr bitmap_size = ALIGN(((mem->memory_size) >> TARGET_PAGE_BITS),
+    hwaddr bitmap_size = ALIGN(mem->memory_size / qemu_real_host_page_size,
                                         /*HOST_LONG_BITS*/ 64) / 8;
     mem->dirty_bmap = g_malloc0(bitmap_size);
 }
@@ -669,6 +673,10 @@ out:
 #define KVM_CLEAR_LOG_ALIGN  (qemu_real_host_page_size << KVM_CLEAR_LOG_SHIFT)
 #define KVM_CLEAR_LOG_MASK   (-KVM_CLEAR_LOG_ALIGN)
 
+/*
+ * As the granule of kvm dirty log is qemu_real_host_page_size,
+ * @start and @size are expected and restricted to align to it.
+ */
 static int kvm_log_clear_one_slot(KVMSlot *mem, int as_id, uint64_t start,
                                   uint64_t size)
 {
@@ -678,6 +686,9 @@ static int kvm_log_clear_one_slot(KVMSlot *mem, int as_id, uint64_t start,
     unsigned long *bmap_clear = NULL, psize = qemu_real_host_page_size;
     int ret;
 
+    /* Make sure start and size are qemu_real_host_page_size aligned */
+    assert(QEMU_IS_ALIGNED(start | size, psize));
+
     /*
      * We need to extend either the start or the size or both to
      * satisfy the KVM interface requirement.  Firstly, do the start