From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:51384) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1UGWmh-0003mS-Ij for qemu-devel@nongnu.org; Fri, 15 Mar 2013 11:43:09 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1UGWmc-0005MT-Qk for qemu-devel@nongnu.org; Fri, 15 Mar 2013 11:43:07 -0400 Received: from hall.aurel32.net ([2001:470:1f15:c4f::1]:43971) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1UGWmc-0005JB-KN for qemu-devel@nongnu.org; Fri, 15 Mar 2013 11:43:02 -0400 Date: Fri, 15 Mar 2013 16:42:52 +0100 From: Aurelien Jarno Message-ID: <20130315154252.GC27432@hall.aurel32.net> References: <1362442784-22324-1-git-send-email-aurelien@aurel32.net> <20130305004438.GF23040@ohm.aurel32.net> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-15 Content-Disposition: inline In-Reply-To: Sender: Aurelien Jarno Subject: Re: [Qemu-devel] [PATCH] hw/vexpress: set default block type to SD List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Peter Maydell Cc: qemu-devel@nongnu.org On Fri, Mar 15, 2013 at 03:35:48PM +0000, Peter Maydell wrote: > On 5 March 2013 00:44, Aurelien Jarno wrote: > > On Tue, Mar 05, 2013 at 08:22:57AM +0800, Peter Maydell wrote: > >> What effect does this actually have on the user experience? > > > > The effect is that the user don't has to specify the interface type. > > Basically: > > > > -drive file=/path/to/file,if=sd > > can be replaced by > > -drive file=/path/to/file > > > > It means the user doesn't have to know the details of the machine to > > know how to attach a disk. Note that the user here can also be a script, > > which then becomes a bit simpler. > > I'm not convinced this is a good thing -- I think you should have > to know that you're attaching an SD card and not a hard disk, > because the performance is much worse. In particular if you > don't specify 'cache=writeback' your performance will be > dreadful, so you need to do something different from hard > disks anyhow. > Being a good thing or not, the current code is wrong: the default interface type is set to SCSI (I guess it has been copied from versatilepb.c), while the vexpress machine has no SCSI interface. -- Aurelien Jarno GPG: 1024D/F1BCDB73 aurelien@aurel32.net http://www.aurel32.net