From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from relay.smtp-ext.broadcom.com (relay.smtp-ext.broadcom.com [192.19.166.228]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id AE5EE517BC5; Mon, 21 Sep 2026 22:00:35 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=192.19.166.228 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790028037; cv=none; b=gB33gTYQiF9/psKeQvRLIYTyn2pqo+1UxH+fOe3yRa+TyVftdPJ+2SI0exhLq/JdbWc8V8TYeQCjqw+A7uMee7R6juH/vJowN6G6qG4z0u2+oFv8sv3aiszcnpgEzgRixetnt8ydNe8R9l0dI3raPpaGKsq2w+0q4zOL1eZsTps= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790028037; c=relaxed/simple; bh=XweC/BmVghZObXd0oGdfwJcXunlAoagyj0XiejVWlmw=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=MyvqTev98UwlQ49kfOf5ycgMFntATLZWDHzPPvaGrEHIMHwJtiy6N0lTnoCyYUOsfnpKoxP+4i3Uaho/tck7symUkw4+ezlb9mZe9PtW4y0IzeGrRqbPrYzM/1UQ1I8EalBOQTrVX7FFTtkc8hMm0bLHM3ZlTKtx+8Af7auL3Lo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=broadcom.com; spf=fail smtp.mailfrom=broadcom.com; dkim=pass (1024-bit key) header.d=broadcom.com header.i=@broadcom.com header.b=uEPc1U+R; arc=none smtp.client-ip=192.19.166.228 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=broadcom.com Authentication-Results: smtp.subspace.kernel.org; spf=fail smtp.mailfrom=broadcom.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=broadcom.com header.i=@broadcom.com header.b="uEPc1U+R" Received: from mail-lvn-it-01.broadcom.com (mail-lvn-it-01.lvn.broadcom.net [10.36.132.253]) by relay.smtp-ext.broadcom.com (Postfix) with ESMTP id 979E5C0087BC; Mon, 21 Sep 2026 15:00:29 -0700 (PDT) DKIM-Filter: OpenDKIM Filter v2.11.0 relay.smtp-ext.broadcom.com 979E5C0087BC DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=broadcom.com; s=dkimrelay; t=1790028029; bh=XweC/BmVghZObXd0oGdfwJcXunlAoagyj0XiejVWlmw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=uEPc1U+RRTkYJJCSepamm3PPceilbzVQY/IiOLwFA6kF9o46Om5WCFNEVOXy3SF60 OQT4ogxDj8gw8M/y7Df1x+uOlnAAraN17TrWkZp8FVzdJEeZ/gYuD+dKcNYfY5dbCv wnwYwa2bGFctG+Eq8+/y4owh1MykkEGDht9+QjFs= Received: from stbirv-lnx-1.igp.broadcom.net (stbirv-lnx-1.igp.broadcom.net [10.67.48.32]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mail-lvn-it-01.broadcom.com (Postfix) with ESMTPSA id 734F9AE4; Mon, 21 Sep 2026 15:00:29 -0700 (PDT) From: Florian Fainelli To: netdev@vger.kernel.org Cc: Florian Fainelli , Nicolai Buchwitz , Doug Berger , Broadcom internal kernel review list , Andrew Lunn , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Zak Kemble , Simon Horman , Ryo Takakura , linux-kernel@vger.kernel.org (open list) Subject: [PATCH net v2 5/5] net: bcmgenet: mask DMA_TIMEOUT_MASK when reading DMA_RING0_TIMEOUT Date: Mon, 21 Sep 2026 15:00:21 -0700 Message-Id: <20260921220021.281418-6-florian.fainelli@broadcom.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20260921220021.281418-1-florian.fainelli@broadcom.com> References: <20260921220021.281418-1-florian.fainelli@broadcom.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit bcmgenet_get_coalesce() reads DMA_RING0_TIMEOUT to calculate rx_coalesce_usecs without masking out bits outside DMA_TIMEOUT_MASK (16 bits). If upper bits are non-zero or contain status/flags, the computed value of rx_coalesce_usecs returned to userspace via ethtool becomes corrupted. Mask the register read with DMA_TIMEOUT_MASK before computing the timeout in microseconds. Fixes: 4a29645bfe6c ("net: bcmgenet: Implement RX coalescing control knobs") Assisted-by: LLM Reviewed-by: Nicolai Buchwitz Signed-off-by: Florian Fainelli --- drivers/net/ethernet/broadcom/genet/bcmgenet.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/net/ethernet/broadcom/genet/bcmgenet.c b/drivers/net/ethernet/broadcom/genet/bcmgenet.c index e9d9d3d7b636..ef3b750630d3 100644 --- a/drivers/net/ethernet/broadcom/genet/bcmgenet.c +++ b/drivers/net/ethernet/broadcom/genet/bcmgenet.c @@ -852,7 +852,8 @@ static int bcmgenet_get_coalesce(struct net_device *dev, ec->rx_max_coalesced_frames = bcmgenet_rdma_ring_readl(priv, 0, DMA_MBUF_DONE_THRESH); ec->rx_coalesce_usecs = - bcmgenet_rdma_readl(priv, DMA_RING0_TIMEOUT) * 8192 / 1000; + (bcmgenet_rdma_readl(priv, DMA_RING0_TIMEOUT) & + DMA_TIMEOUT_MASK) * 8192 / 1000; for (i = 0; i <= priv->hw_params->rx_queues; i++) { ring = &priv->rx_rings[i]; -- 2.34.1