From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:56185) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Tbnhl-0006ml-Or for qemu-devel@nongnu.org; Fri, 23 Nov 2012 02:29:46 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Tbnhh-0004ML-BT for qemu-devel@nongnu.org; Fri, 23 Nov 2012 02:29:41 -0500 Received: from mail-ee0-f45.google.com ([74.125.83.45]:48640) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Tbnhh-0004MG-4p for qemu-devel@nongnu.org; Fri, 23 Nov 2012 02:29:37 -0500 Received: by mail-ee0-f45.google.com with SMTP id d49so5223929eek.4 for ; Thu, 22 Nov 2012 23:29:36 -0800 (PST) Sender: Paolo Bonzini Message-ID: <50AF25DC.4070604@redhat.com> Date: Fri, 23 Nov 2012 08:29:32 +0100 From: Paolo Bonzini MIME-Version: 1.0 References: <1353647324-19840-1-git-send-email-david@gibson.dropbear.id.au> In-Reply-To: <1353647324-19840-1-git-send-email-david@gibson.dropbear.id.au> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH] virtio-scsi Fix some endian bugs with virtio-scsi List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: David Gibson Cc: aliguori@us.ibm.com, Paul 'Rusty' Russell , qemu-devel@nongnu.org Il 23/11/2012 06:08, David Gibson ha scritto: > The virtio-scsi specification does not specify the correct endianness for > fields in the request structure. It's therefore best to assume that it is > "guest native" endian since that's the (stupid and poorly defined) norm in > virtio. Indeed. > However, the qemu device for virtio-scsi has no byteswaps at all, and so > will break if the guest has different endianness from the host. This patch > fixes it by adding tswap() calls for the sense_len and resid fields in > the request structure. In theory status_qualifier needs swaps as well, > but that field is never actually touched. The tag field is a uint64_t, but > since its value is completely arbitrary, it might as well be uint8_t[8] > and so it does not need swapping. Thanks, I adjusted the patch to use a separate variable for the argument of tswap32 and pushed to the scsi branch. Paolo > Cc: Paolo Bonzini > Cc: Paul 'Rusty' Russell > Signed-off-by: David Gibson > --- > hw/virtio-scsi.c | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) > > diff --git a/hw/virtio-scsi.c b/hw/virtio-scsi.c > index 7d546f6..9d27d1d 100644 > --- a/hw/virtio-scsi.c > +++ b/hw/virtio-scsi.c > @@ -428,11 +428,12 @@ static void virtio_scsi_command_complete(SCSIRequest *r, uint32_t status, > req->resp.cmd->response = VIRTIO_SCSI_S_OK; > req->resp.cmd->status = status; > if (req->resp.cmd->status == GOOD) { > - req->resp.cmd->resid = resid; > + req->resp.cmd->resid = tswap32(resid); > } else { > req->resp.cmd->resid = 0; > req->resp.cmd->sense_len = > - scsi_req_get_sense(r, req->resp.cmd->sense, VIRTIO_SCSI_SENSE_SIZE); > + tswap32(scsi_req_get_sense(r, req->resp.cmd->sense, > + VIRTIO_SCSI_SENSE_SIZE)); > } > virtio_scsi_complete_req(req); > } >