Merging KVM live migration upstream

[Jan Kiszka <jan.kiszka@xxxxxx>]

Avi or Uri,

could you explain the first and third hunk? Why are they needed in
qemu-kvm, and will we also need something comparable upstream? They do
not look very beautiful.

The second hunk, I guess, should become a kvm hook to
cpu_physical_memory_get_dirty - or is this too costly for other users of
this inline function?

And does anyone knows further migration-related hunks that are missing
upstream (except for the KVM hook in
cpu_physical_memory_set_dirty_tracking)?

Jan

--- qemu/vl.c
+++ qemu-kvm/vl.c
@@ -3097,6 +3204,8 @@ static int ram_load_v1(QEMUFile *f, void
     if (qemu_get_be32(f) != last_ram_offset)
         return -EINVAL;
     for(i = 0; i < last_ram_offset; i+= TARGET_PAGE_SIZE) {
+        if (kvm_enabled() && (i>=0xa0000) && (i<0xc0000)) /* do not access video-addresses */
+            continue;
         ret = ram_get_page(f, qemu_get_ram_ptr(i), TARGET_PAGE_SIZE);
         if (ret)
             return ret;
@@ -3183,6 +3292,15 @@ static int ram_save_block(QEMUFile *f)
     int found = 0;

     while (addr < last_ram_offset) {
+        if (kvm_enabled() && current_addr == 0) {
+            int r;
+            r = kvm_update_dirty_pages_log();
+            if (r) {
+                fprintf(stderr, "%s: update dirty pages log failed %d\n", __FUNCTION__, r);
+                qemu_file_set_error(f);
+                return 0;
+            }
+        }
         if (cpu_physical_memory_get_dirty(current_addr, MIGRATION_DIRTY_FLAG)) {
             uint8_t *p;

@@ -3273,6 +3391,8 @@ static int ram_load_dead(QEMUFile *f, vo
     if (ram_decompress_open(s, f) < 0)
         return -EINVAL;
     for(i = 0; i < last_ram_offset; i+= BDRV_HASH_BLOCK_SIZE) {
+        if (kvm_enabled() && (i>=0xa0000) && (i<0xc0000)) /* do not access video-addresses */
+            continue;
         if (ram_decompress_buf(s, buf, 1) < 0) {
             fprintf(stderr, "Error while reading ram block header\n");
             goto error;

Attachment: signature.asc
Description: OpenPGP digital signature