From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:43704) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZF5IK-0001u0-N8 for qemu-devel@nongnu.org; Tue, 14 Jul 2015 14:51:09 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ZF5IG-0005rw-O6 for qemu-devel@nongnu.org; Tue, 14 Jul 2015 14:51:08 -0400 Received: from mx1.redhat.com ([209.132.183.28]:57452) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZF5IG-0005rq-J9 for qemu-devel@nongnu.org; Tue, 14 Jul 2015 14:51:04 -0400 Date: Tue, 14 Jul 2015 19:51:02 +0100 From: "Richard W.M. Jones" Message-ID: <20150714185102.GA4148@redhat.com> References: <20150713200936.GK1606@HEDWIG.INI.CMU.EDU> <20150714094346.GR29283@redhat.com> <20150714182314.GO1606@HEDWIG.INI.CMU.EDU> <20150714184829.GU29283@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20150714184829.GU29283@redhat.com> Subject: Re: [Qemu-devel] RFC: guest-side retrieval of fw_cfg file List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: "Gabriel L. Somlo" Cc: matt.fleming@intel.com, mdroth@linux.vnet.ibm.com, jordan.l.justen@intel.com, "Gabriel L. Somlo" , qemu-devel@nongnu.org, gleb@cloudius-systems.com, kraxel@redhat.com, pbonzini@redhat.com, Laszlo Ersek On Tue, Jul 14, 2015 at 07:48:29PM +0100, Richard W.M. Jones wrote: > On aarch64 kernel loading is really slow because it can only transfer > (IIRC) 8 bytes at a time, and there are no string instructions we can > use to speed it up. I should note here I'm talking about AAVMF (ie. guest UEFI) which has to load the kernel via fw_cfg. Using the -kernel option qemu-system-aarch64 is really fast because it prepopulates the guest RAM. Rich. -- Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones Read my programming and virtualization blog: http://rwmj.wordpress.com virt-df lists disk usage of guests without needing to install any software inside the virtual machine. Supports Linux and Windows. http://people.redhat.com/~rjones/virt-df/