From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:60676) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ShtbX-0006K4-JG for qemu-devel@nongnu.org; Thu, 21 Jun 2012 22:28:12 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ShtbV-0001Wl-PB for qemu-devel@nongnu.org; Thu, 21 Jun 2012 22:28:11 -0400 Received: from gate.crashing.org ([63.228.1.57]:54379) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ShtbV-0001Wd-Gp for qemu-devel@nongnu.org; Thu, 21 Jun 2012 22:28:09 -0400 Message-ID: <1340332080.16104.16.camel@pasglop> From: Benjamin Herrenschmidt Date: Fri, 22 Jun 2012 12:28:00 +1000 In-Reply-To: <4FE319DE.7070809@codemonkey.ws> References: <1340087992-2399-1-git-send-email-benh@kernel.crashing.org> <1340087992-2399-5-git-send-email-benh@kernel.crashing.org> <4FE23E30.50302@codemonkey.ws> <1340228168.28143.178.camel@pasglop> <4FE2434D.2010901@codemonkey.ws> <1340229726.28143.200.camel@pasglop> <20120621073338.GA31732@redhat.com> <4FE319DE.7070809@codemonkey.ws> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Mime-Version: 1.0 Subject: Re: [Qemu-devel] [PATCH 04/13] usb-ohci: Use universal DMA helper functions List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Anthony Liguori Cc: David Gibson , Gerd Hoffmann , qemu-devel@nongnu.org, "Michael S. Tsirkin" On Thu, 2012-06-21 at 07:55 -0500, Anthony Liguori wrote: > As long as we scrub the buffers, returning an unhandled error seems okay to me. > > I've long thought we should have some sort of generic way to throw an error and > effectively pause a single device. I'm not sure how it would work in practice > though. I'll scrub the buffer in dma_memory_rw when reading from the guest in all failure cases to ensure that we don't use a buffer of stale qemu data. In addition I'm doing a separate patch that I'll post later (needs a bit more time) that improves OHCI's error handling. Cheers, Ben.