From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from [140.186.70.92] (port=55508 helo=eggs.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1OTVqQ-0002km-FI for qemu-devel@nongnu.org; Tue, 29 Jun 2010 04:07:04 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.69) (envelope-from ) id 1OTVqI-0006RW-Fr for qemu-devel@nongnu.org; Tue, 29 Jun 2010 04:06:58 -0400 Received: from mx1.redhat.com ([209.132.183.28]:60387) by eggs.gnu.org with esmtp (Exim 4.69) (envelope-from ) id 1OTVqI-0006RB-8x for qemu-devel@nongnu.org; Tue, 29 Jun 2010 04:06:54 -0400 Message-ID: <4C29A993.4030708@redhat.com> Date: Tue, 29 Jun 2010 10:06:43 +0200 From: Gerd Hoffmann MIME-Version: 1.0 Subject: Re: [Qemu-devel] Re: [PATCH 08/12] block: Catch attempt to attach multiple devices to a blockdev References: <1277484812-22012-1-git-send-email-armbru@redhat.com> <1277484812-22012-9-git-send-email-armbru@redhat.com> <20100626101146.GC27699@lst.de> <20100627093609.GA12016@lst.de> <4C285C51.9020003@redhat.com> In-Reply-To: <4C285C51.9020003@redhat.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Kevin Wolf Cc: qemu-devel@nongnu.org, Christoph Hellwig , Markus Armbruster Hi, >> Note that currently the usb storage emulation is extremly broken anyway, >> just writing to it produces I/O errors after a short while. This means >> it can't be used very much at all. > > When I tried last time, it did produce lots of kernel error messages in > the guest, but in the end the data was written correctly. So it doesn't > seem to be completely unusable. I think it is actually the linux kernel being at fault here. I've seen I/O errors on real hardware too, on my pretty old laptop which has usb 1.1 only. Probably something like timeouts being *way* too low for usb 1.1 xfer speeds. cheers, Gerd