From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:55773) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bn1JT-0000b4-M8 for qemu-devel@nongnu.org; Thu, 22 Sep 2016 06:33:13 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1bn1JP-0004ee-E0 for qemu-devel@nongnu.org; Thu, 22 Sep 2016 06:33:06 -0400 Received: from mx1.redhat.com ([209.132.183.28]:55432) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bn1JP-0004eO-7s for qemu-devel@nongnu.org; Thu, 22 Sep 2016 06:33:03 -0400 References: <1474540298-4152-1-git-send-email-ppandit@redhat.com> From: Paolo Bonzini Message-ID: <44697264-cc82-7c93-5b04-241bfe4035ab@redhat.com> Date: Thu, 22 Sep 2016 12:32:58 +0200 MIME-Version: 1.0 In-Reply-To: <1474540298-4152-1-git-send-email-ppandit@redhat.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH v2] net: imx: limit buffer descriptor count List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: P J P , Qemu Developers Cc: Jason Wang , Li Qiang , Prasad J Pandit On 22/09/2016 12:31, P J P wrote: > From: Prasad J Pandit > > i.MX Fast Ethernet Controller uses buffer descriptors to manage > data flow to/fro receive & transmit queues. While transmitting > packets, it could continue to read buffer descriptors if a buffer > descriptor has length of zero and has crafted values in bd.flags. > Set an upper limit to number of buffer descriptors. > > Reported-by: Li Qiang > Signed-off-by: Prasad J Pandit > --- > hw/net/imx_fec.c | 6 ++++-- > 1 file changed, 4 insertions(+), 2 deletions(-) > > Update per > -> https://lists.gnu.org/archive/html/qemu-devel/2016-09/msg05284.html > > diff --git a/hw/net/imx_fec.c b/hw/net/imx_fec.c > index e60e338..547fa99 100644 > --- a/hw/net/imx_fec.c > +++ b/hw/net/imx_fec.c > @@ -94,6 +94,8 @@ static const VMStateDescription vmstate_imx_fec = { > #define PHY_INT_PARFAULT (1 << 2) > #define PHY_INT_AUTONEG_PAGE (1 << 1) > > +#define IMX_MAX_DESC 1024 > + > static void imx_fec_update(IMXFECState *s); > > /* > @@ -264,12 +266,12 @@ static void imx_fec_update(IMXFECState *s) > > static void imx_fec_do_tx(IMXFECState *s) > { > - int frame_size = 0; > + int frame_size = 0, descnt = 0; > uint8_t frame[FEC_MAX_FRAME_SIZE]; > uint8_t *ptr = frame; > uint32_t addr = s->tx_descriptor; > > - while (1) { > + while (descnt++ < IMX_MAX_DESC) { > IMXFECBufDesc bd; > int len; > > Reviewed-by: Paolo Bonzini