From 0827b9e97d443781a17a21c64695940675aa1f8a Mon Sep 17 00:00:00 2001 From: Ashijeet Acharya Date: Wed, 8 Feb 2017 19:58:45 +0530 Subject: [PATCH] migrate: Introduce zero RAM checks to skip RAM migration MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Migration of a "none" machine with no RAM crashes abruptly as bitmap_new() fails and thus aborts. Instead place zero RAM checks at appropriate places to skip migration of RAM in this case and complete migration successfully for devices only. Signed-off-by: Ashijeet Acharya Message-Id: <1486564125-31366-1-git-send-email-ashijeetacharya@gmail.com> Reviewed-by: Dr. David Alan Gilbert Reviewed-by: Philippe Mathieu-Daudé Signed-off-by: Dr. David Alan Gilbert --- migration/ram.c | 22 +++++++++++++++------- 1 file changed, 15 insertions(+), 7 deletions(-) diff --git a/migration/ram.c b/migration/ram.c index 67f2efbc59..f289fcddd5 100644 --- a/migration/ram.c +++ b/migration/ram.c @@ -1346,6 +1346,11 @@ static int ram_find_and_save_block(QEMUFile *f, bool last_stage, ram_addr_t dirty_ram_abs; /* Address of the start of the dirty page in ram_addr_t space */ + /* No dirty page as there is zero RAM */ + if (!ram_bytes_total()) { + return pages; + } + pss.block = last_seen_block; pss.offset = last_offset; pss.complete_round = false; @@ -1952,14 +1957,17 @@ static int ram_save_init_globals(void) bytes_transferred = 0; reset_ram_globals(); - ram_bitmap_pages = last_ram_offset() >> TARGET_PAGE_BITS; migration_bitmap_rcu = g_new0(struct BitmapRcu, 1); - migration_bitmap_rcu->bmap = bitmap_new(ram_bitmap_pages); - bitmap_set(migration_bitmap_rcu->bmap, 0, ram_bitmap_pages); - - if (migrate_postcopy_ram()) { - migration_bitmap_rcu->unsentmap = bitmap_new(ram_bitmap_pages); - bitmap_set(migration_bitmap_rcu->unsentmap, 0, ram_bitmap_pages); + /* Skip setting bitmap if there is no RAM */ + if (ram_bytes_total()) { + ram_bitmap_pages = last_ram_offset() >> TARGET_PAGE_BITS; + migration_bitmap_rcu->bmap = bitmap_new(ram_bitmap_pages); + bitmap_set(migration_bitmap_rcu->bmap, 0, ram_bitmap_pages); + + if (migrate_postcopy_ram()) { + migration_bitmap_rcu->unsentmap = bitmap_new(ram_bitmap_pages); + bitmap_set(migration_bitmap_rcu->unsentmap, 0, ram_bitmap_pages); + } } /* -- 2.11.4.GIT