From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:53232) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cWKBQ-0006Wp-7m for qemu-devel@nongnu.org; Wed, 25 Jan 2017 04:48:05 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1cWKBL-0003ci-BB for qemu-devel@nongnu.org; Wed, 25 Jan 2017 04:48:04 -0500 Received: from mx1.redhat.com ([209.132.183.28]:42456) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1cWKBL-0003bE-5c for qemu-devel@nongnu.org; Wed, 25 Jan 2017 04:47:59 -0500 Received: from int-mx13.intmail.prod.int.phx2.redhat.com (int-mx13.intmail.prod.int.phx2.redhat.com [10.5.11.26]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 690AF80460 for ; Wed, 25 Jan 2017 09:47:58 +0000 (UTC) From: Juan Quintela In-Reply-To: <20170106182823.1960-2-dgilbert@redhat.com> (David Alan Gilbert's message of "Fri, 6 Jan 2017 18:28:09 +0000") References: <20170106182823.1960-1-dgilbert@redhat.com> <20170106182823.1960-2-dgilbert@redhat.com> Reply-To: quintela@redhat.com Date: Wed, 25 Jan 2017 10:47:51 +0100 Message-ID: <871svr8o8o.fsf@emacs.mitica> MIME-Version: 1.0 Content-Type: text/plain Subject: Re: [Qemu-devel] [PATCH 01/15] postcopy: Transmit and compare individual page sizes List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: "Dr. David Alan Gilbert (git)" Cc: qemu-devel@nongnu.org, amit.shah@redhat.com, aarcange@redhat.com "Dr. David Alan Gilbert (git)" wrote: > From: "Dr. David Alan Gilbert" > > When using postcopy with hugepages, we require the source > and destination page sizes for any RAMBlock to match. > > Transmit them as part of the RAM information header and > fail if there's a difference. > > Signed-off-by: Dr. David Alan Gilbert > --- > migration/ram.c | 15 +++++++++++++++ > 1 file changed, 15 insertions(+) > > diff --git a/migration/ram.c b/migration/ram.c > index a1c8089..39998f5 100644 > --- a/migration/ram.c > +++ b/migration/ram.c > @@ -1970,6 +1970,9 @@ static int ram_save_setup(QEMUFile *f, void *opaque) > qemu_put_byte(f, strlen(block->idstr)); > qemu_put_buffer(f, (uint8_t *)block->idstr, strlen(block->idstr)); > qemu_put_be64(f, block->used_length); > + if (migrate_postcopy_ram() && block->page_size != qemu_host_page_size) { > + qemu_put_be64(f, block->page_size); > + } Hi 1- can different block have different page_size? 2- can we remove the migrate_postocpy_ram() check and just send it for newer versions and not for older ones? > } > > rcu_read_unlock(); > @@ -2536,6 +2539,18 @@ static int ram_load(QEMUFile *f, void *opaque, int version_id) > error_report_err(local_err); > } > } > + /* For postcopy we need to check hugepage sizes match */ > + if (migrate_postcopy_ram() && > + block->page_size != qemu_host_page_size) { > + uint64_t remote_page_size = qemu_get_be64(f); > + if (remote_page_size != block->page_size) { > + error_report("Mismatched RAM page size %s " > + "(local) %" PRId64 "!= %" PRId64, > + id, block->page_size, > + remote_page_size); > + ret = -EINVAL; > + } > + } > ram_control_load_hook(f, RAM_CONTROL_BLOCK_REG, > block->idstr); > } else {