1 files changed, 14 insertions, 25 deletions

diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c
index 90c88b517d..f290f487a5 100644
--- a/accel/kvm/kvm-all.c
+++ b/accel/kvm/kvm-all.c
@@ -197,26 +197,20 @@ static hwaddr kvm_align_section(MemoryRegionSection *section,
                                 hwaddr *start)
 {
     hwaddr size = int128_get64(section->size);
-    hwaddr delta;
-
-    *start = section->offset_within_address_space;
+    hwaddr delta, aligned;
 
     /* kvm works in page size chunks, but the function may be called
        with sub-page size and unaligned start address. Pad the start
        address to next and truncate size to previous page boundary. */
-    delta = qemu_real_host_page_size - (*start & ~qemu_real_host_page_mask);
-    delta &= ~qemu_real_host_page_mask;
-    *start += delta;
+    aligned = ROUND_UP(section->offset_within_address_space,
+                       qemu_real_host_page_size);
+    delta = aligned - section->offset_within_address_space;
+    *start = aligned;
     if (delta > size) {
         return 0;
     }
-    size -= delta;
-    size &= qemu_real_host_page_mask;
-    if (*start & ~qemu_real_host_page_mask) {
-        return 0;
-    }
 
-    return size;
+    return (size - delta) & qemu_real_host_page_mask;
 }
 
 int kvm_physical_memory_addr_from_host(KVMState *s, void *ram,
@@ -394,8 +388,8 @@ static int kvm_section_update_flags(KVMMemoryListener *kml,
 
     mem = kvm_lookup_matching_slot(kml, start_addr, size);
     if (!mem) {
-        fprintf(stderr, "%s: error finding slot\n", __func__);
-        abort();
+        /* We don't have a slot if we want to trap every access. */
+        return 0;
     }
 
     return kvm_slot_update_flags(kml, mem, section->mr);
@@ -470,8 +464,8 @@ static int kvm_physical_sync_dirty_bitmap(KVMMemoryListener *kml,
     if (size) {
         mem = kvm_lookup_matching_slot(kml, start_addr, size);
         if (!mem) {
-            fprintf(stderr, "%s: error finding slot\n", __func__);
-            abort();
+            /* We don't have a slot if we want to trap every access. */
+            return 0;
         }
 
         /* XXX bad kernel interface alert
@@ -717,11 +711,12 @@ static void kvm_set_phys_mem(KVMMemoryListener *kml,
         return;
     }
 
+    /* use aligned delta to align the ram address */
     ram = memory_region_get_ram_ptr(mr) + section->offset_within_region +
-          (section->offset_within_address_space - start_addr);
+          (start_addr - section->offset_within_address_space);
 
-    mem = kvm_lookup_matching_slot(kml, start_addr, size);
     if (!add) {
+        mem = kvm_lookup_matching_slot(kml, start_addr, size);
         if (!mem) {
             return;
         }
@@ -733,19 +728,13 @@ static void kvm_set_phys_mem(KVMMemoryListener *kml,
         mem->memory_size = 0;
         err = kvm_set_user_memory_region(kml, mem);
         if (err) {
-            fprintf(stderr, "%s: error unregistering overlapping slot: %s\n",
+            fprintf(stderr, "%s: error unregistering slot: %s\n",
                     __func__, strerror(-err));
             abort();
         }
         return;
     }
 
-    if (mem) {
-        /* update the slot */
-        kvm_slot_update_flags(kml, mem, mr);
-        return;
-    }
-
     /* register the new slot */
     mem = kvm_alloc_slot(kml);
     mem->memory_size = size;