Merge remote-tracking branch 'remotes/juanquintela/tags/migration/20161014' into staging

migration/next for 20161014

# gpg: Signature made Fri 14 Oct 2016 16:24:13 BST
# gpg:                using RSA key 0xF487EF185872D723
# gpg: Good signature from "Juan Quintela <quintela@redhat.com>"
# gpg:                 aka "Juan Quintela <quintela@trasno.org>"
# Primary key fingerprint: 1899 FF8E DEBF 58CC EE03  4B82 F487 EF18 5872 D723

* remotes/juanquintela/tags/migration/20161014:
  docs/xbzrle: correction
  migrate: move max-bandwidth and downtime-limit to migrate_set_parameter
  migration: Fix seg with missing port
  migration/postcopy: Explicitly disallow huge pages
  RAMBlocks: Store page size
  Postcopy vs xbzrle: Don't send xbzrle pages once in postcopy [for 2.8]
  migrate: Fix bounds check for migration parameters in migration.c
  migrate: Use boxed qapi for migrate-set-parameters
  migrate: Share common MigrationParameters struct
  migrate: Fix cpu-throttle-increment regression in HMP
  migration/rdma: Don't flag an error when we've been told about one
  migration: Make failed migration load set file error
  migration/rdma: Pass qemu_file errors across link
  migration: Report values for comparisons
  migration: report an error giving the failed field

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

1 files changed, 24 insertions, 0 deletions

diff --git a/migration/postcopy-ram.c b/migration/postcopy-ram.c
index 9b0477835f..a40dddbaf6 100644
--- a/migration/postcopy-ram.c
+++ b/migration/postcopy-ram.c
@@ -85,6 +85,24 @@ static bool ufd_version_check(int ufd)
 }
 
 /*
+ * Check for things that postcopy won't support; returns 0 if the block
+ * is fine.
+ */
+static int check_range(const char *block_name, void *host_addr,
+                      ram_addr_t offset, ram_addr_t length, void *opaque)
+{
+    RAMBlock *rb = qemu_ram_block_by_name(block_name);
+
+    if (qemu_ram_pagesize(rb) > getpagesize()) {
+        error_report("Postcopy doesn't support large page sizes yet (%s)",
+                     block_name);
+        return -E2BIG;
+    }
+
+    return 0;
+}
+
+/*
  * Note: This has the side effect of munlock'ing all of RAM, that's
  * normally fine since if the postcopy succeeds it gets turned back on at the
  * end.
@@ -104,6 +122,12 @@ bool postcopy_ram_supported_by_host(void)
         goto out;
     }
 
+    /* Check for anything about the RAMBlocks we don't support */
+    if (qemu_ram_foreach_block(check_range, NULL)) {
+        /* check_range will have printed its own error */
+        goto out;
+    }
+
     ufd = syscall(__NR_userfaultfd, O_CLOEXEC);
     if (ufd == -1) {
         error_report("%s: userfaultfd not available: %s", __func__,