From patchwork Mon Sep 9 23:09:08 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sean Anderson X-Patchwork-Id: 13797672 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id CFBB2ECE58C for ; Mon, 9 Sep 2024 23:10:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: MIME-Version:Message-Id:Date:Subject:Cc:To:From:Reply-To:Content-Type: Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender: Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References:List-Owner; bh=oYqzLmU8Wwh+yV2OBnKEU0j9ng/GD4hfiT1RPK+msTg=; b=AeyrodSa1LKa8ilXp99N1PWTNb xteDP52xzg7v3QpC5/n8kM0wAfRqvqqUIMjzCUtgj/EOsFf+hULH5sVnEVlLksfw2Wv+p1VQZPu8Y uTBYYk4chn6WLGZTRmrOiG8qiwyW+/CIWKQC3eWKnAx8xoUgNsRb7WFSnsT340soRChWOrYzAGYKS 3lO0scoiALdtTuzSIwmvLzZGM8654Y6cbF3ntzuj1M5xHa9yY2Fbzm0UnVxLBzP1hJco9062bdO9C yDHavz3Qutal8lcXmixJNd+KZjpUdA5PochgF+iejeo1JwtngQvWQ4RtEIx6lTqF7fseqvCogsYsc EgqmfbCw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1snnWd-00000003Xw3-0pVw; Mon, 09 Sep 2024 23:10:27 +0000 Received: from out-177.mta1.migadu.com ([95.215.58.177]) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1snnVa-00000003Xoy-3AWy for linux-arm-kernel@lists.infradead.org; Mon, 09 Sep 2024 23:09:25 +0000 X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1725923355; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=oYqzLmU8Wwh+yV2OBnKEU0j9ng/GD4hfiT1RPK+msTg=; b=fokhnc608jJF/K2dN/Aq8rKKEJ2UXmEzP/3e38gbFBr/MY6gB2YUsF7heYJMyGirCtau99 TYrQFQ/6YG4PPccrwhSQJ4CrvjxLGow9O3ieQNuuBsunpKWOH+/UvJ0C8/kMbQLU9Hy5lR Dn7XxZVg/T74ba+8ng8uRF3zbBcF7Uc= From: Sean Anderson To: Radhey Shyam Pandey , "David S . Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , netdev@vger.kernel.org Cc: Andy Chiu , linux-kernel@vger.kernel.org, Simon Horman , Ariane Keller , Daniel Borkmann , linux-arm-kernel@lists.infradead.org, Michal Simek , Sean Anderson Subject: [PATCH net v2] net: xilinx: axienet: Fix IRQ coalescing packet count overflow Date: Mon, 9 Sep 2024 19:09:08 -0400 Message-Id: <20240909230908.1319982-1-sean.anderson@linux.dev> MIME-Version: 1.0 X-Migadu-Flow: FLOW_OUT X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240909_160923_820617_8F8C9EDC X-CRM114-Status: GOOD ( 12.82 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org If coalece_count is greater than 255 it will not fit in the register and will overflow. This can be reproduced by running # ethtool -C ethX rx-frames 256 which will result in a timeout of 0us instead. Fix this by clamping the counts to the maximum value. Signed-off-by: Sean Anderson Fixes: 8a3b7a252dca ("drivers/net/ethernet/xilinx: added Xilinx AXI Ethernet driver") Reviewed-by: Shannon Nelson --- Changes in v2: - Use FIELD_MAX to extract the max value from the mask - Expand the commit message with an example on how to reproduce this issue drivers/net/ethernet/xilinx/xilinx_axienet.h | 5 ++--- drivers/net/ethernet/xilinx/xilinx_axienet_main.c | 8 ++++++-- 2 files changed, 8 insertions(+), 5 deletions(-) diff --git a/drivers/net/ethernet/xilinx/xilinx_axienet.h b/drivers/net/ethernet/xilinx/xilinx_axienet.h index 1223fcc1a8da..54db69893565 100644 --- a/drivers/net/ethernet/xilinx/xilinx_axienet.h +++ b/drivers/net/ethernet/xilinx/xilinx_axienet.h @@ -109,11 +109,10 @@ #define XAXIDMA_BD_CTRL_TXEOF_MASK 0x04000000 /* Last tx packet */ #define XAXIDMA_BD_CTRL_ALL_MASK 0x0C000000 /* All control bits */ -#define XAXIDMA_DELAY_MASK 0xFF000000 /* Delay timeout counter */ -#define XAXIDMA_COALESCE_MASK 0x00FF0000 /* Coalesce counter */ +#define XAXIDMA_DELAY_MASK ((u32)0xFF000000) /* Delay timeout counter */ +#define XAXIDMA_COALESCE_MASK ((u32)0x00FF0000) /* Coalesce counter */ #define XAXIDMA_DELAY_SHIFT 24 -#define XAXIDMA_COALESCE_SHIFT 16 #define XAXIDMA_IRQ_IOC_MASK 0x00001000 /* Completion intr */ #define XAXIDMA_IRQ_DELAY_MASK 0x00002000 /* Delay interrupt */ diff --git a/drivers/net/ethernet/xilinx/xilinx_axienet_main.c b/drivers/net/ethernet/xilinx/xilinx_axienet_main.c index 9eb300fc3590..89b63695293d 100644 --- a/drivers/net/ethernet/xilinx/xilinx_axienet_main.c +++ b/drivers/net/ethernet/xilinx/xilinx_axienet_main.c @@ -252,7 +252,9 @@ static u32 axienet_usec_to_timer(struct axienet_local *lp, u32 coalesce_usec) static void axienet_dma_start(struct axienet_local *lp) { /* Start updating the Rx channel control register */ - lp->rx_dma_cr = (lp->coalesce_count_rx << XAXIDMA_COALESCE_SHIFT) | + lp->rx_dma_cr = FIELD_PREP(XAXIDMA_COALESCE_MASK, + min(lp->coalesce_count_rx, + FIELD_MAX(XAXIDMA_COALESCE_MASK))) | XAXIDMA_IRQ_IOC_MASK | XAXIDMA_IRQ_ERROR_MASK; /* Only set interrupt delay timer if not generating an interrupt on * the first RX packet. Otherwise leave at 0 to disable delay interrupt. @@ -264,7 +266,9 @@ static void axienet_dma_start(struct axienet_local *lp) axienet_dma_out32(lp, XAXIDMA_RX_CR_OFFSET, lp->rx_dma_cr); /* Start updating the Tx channel control register */ - lp->tx_dma_cr = (lp->coalesce_count_tx << XAXIDMA_COALESCE_SHIFT) | + lp->tx_dma_cr = FIELD_PREP(XAXIDMA_COALESCE_MASK, + min(lp->coalesce_count_tx, + FIELD_MAX(XAXIDMA_COALESCE_MASK))) | XAXIDMA_IRQ_IOC_MASK | XAXIDMA_IRQ_ERROR_MASK; /* Only set interrupt delay timer if not generating an interrupt on * the first TX packet. Otherwise leave at 0 to disable delay interrupt.