From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Niklas Cassel , Giuseppe Cavallaro , Alexandre TORGUE , "David S. Miller" Subject: [PATCH 4.11 019/150] net: stmmac: fix completely hung TX when using TSO Date: Mon, 12 Jun 2017 17:23:46 +0200 Message-Id: <20170612152520.280861768@linuxfoundation.org> In-Reply-To: <20170612152519.404936272@linuxfoundation.org> References: <20170612152519.404936272@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: 4.11-stable review patch. If anyone has any objections, please let me know. ------------------ From: Niklas Cassel [ Upstream commit 426849e6611f2092553f8d53372ae310818a6292 ] stmmac_tso_allocator can fail to set the Last Descriptor bit on a descriptor that actually was the last descriptor. This happens when the buffer of the last descriptor ends up having a size of exactly TSO_MAX_BUFF_SIZE. When the IP eventually reaches the next last descriptor, which actually has the bit set, the DMA will hang. When the DMA hangs, we get a tx timeout, however, since stmmac does not do a complete reset of the IP in stmmac_tx_timeout, we end up in a state with completely hung TX. Signed-off-by: Niklas Cassel Acked-by: Giuseppe Cavallaro Acked-by: Alexandre TORGUE Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c @@ -1950,7 +1950,7 @@ static void stmmac_tso_allocator(struct priv->hw->desc->prepare_tso_tx_desc(desc, 0, buff_size, 0, 1, - (last_segment) && (buff_size < TSO_MAX_BUFF_SIZE), + (last_segment) && (tmp_len <= TSO_MAX_BUFF_SIZE), 0, 0); tmp_len -= TSO_MAX_BUFF_SIZE;