From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out-172.mta1.migadu.com (out-172.mta1.migadu.com [95.215.58.172]) (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 C4EEA1465B4 for ; Thu, 6 Aug 2026 13:37:59 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=95.215.58.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786023481; cv=none; b=X0XSa0j/1yDo+nUXxm58B3Oyfd6wUYlaZ9g5JSrHHnForjuj9g+IIdI4TXLrhYdTE95NsvSKBxizmzOyXT5gWg3Bfxbj5DAf3rMxG520mcoxs6JK+eKmLrDKNHT+4crgfTmwXA9ULZZCdQU7OyEG+am5+lDPVE404wnRtd5hh2s= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786023481; c=relaxed/simple; bh=Iuj8eEALz44CQqthTbjR76qCcfOgWSdYKv4kWbeBxAM=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=mQrOLQtAu7PEZqHi1LV6uDVS41NXUp0P3l1ySIfYqhhbLYeH5IQbC7EBFqDKE8bgIItTuQzdm7jvLzsGNp0dxhPQvdCJcnJgg7m+v9RyPHgLgInYVvnYQKp4Lg4p42K3K0XzDMQLa/gT4e3JapNqJridzxwUIG+dlvxc4BKWkfw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=rq4yHfjK; arc=none smtp.client-ip=95.215.58.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="rq4yHfjK" Message-ID: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1786023477; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=VqUxzqGOpPJdwXbsyUGY1DU6gotHKjUskbv5j+h3a64=; b=rq4yHfjKRCJcj47tsl1w/fqvuc4Kiv9cg2v5m5FC+1+JigamKewQaFzq10TOPCiKi03ihE rTdfmuRqbS0U3sL4oWua2eYFKz0wM9XpA3zFhlMZuoseavh51o8VmgCHEkO97A1pyLYmEd iOcuUrBDrFwkqbWVWQ/TrP7ErM1XCzA= Date: Thu, 6 Aug 2026 14:37:32 +0100 Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Subject: Re: [PATCH net v3 1/2] net: ravb: handle unavailable PTP clock To: xuanqiang.luo@linux.dev, linux-renesas-soc@vger.kernel.org, netdev@vger.kernel.org, niklas.soderlund@ragnatech.se, kuba@kernel.org Cc: paul@pbarker.dev, andrew+netdev@lunn.ch, davem@davemloft.net, edumazet@google.com, pabeni@redhat.com, richardcochran@gmail.com, masaru.nagai.vx@renesas.com, sergei.shtylyov@cogentembedded.com, luoxuanqiang@kylinos.cn, stable@vger.kernel.org References: <20260806095126.57803-1-xuanqiang.luo@linux.dev> <20260806095126.57803-2-xuanqiang.luo@linux.dev> Content-Language: en-US X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Vadim Fedorenko In-Reply-To: <20260806095126.57803-2-xuanqiang.luo@linux.dev> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Migadu-Flow: FLOW_OUT On 06/08/2026 10:51, xuanqiang.luo@linux.dev wrote: > From: Xuanqiang Luo > > The PTP clock is registered by ravb_open(), not ravb_probe(). Therefore, > priv->ptp.clock is NULL between register_netdev() and the first open, and > ethtool -T triggers a NULL dereference in ptp_clock_index(). > > ptp_clock_register() may also return an error pointer, which can reach > ptp_clock_index() or ptp_clock_unregister(). > > Normalize registration errors to NULL and only query or unregister the > clock when it is present. Leave phc_index at -1 when no PHC is registered, > while preserving the static hardware timestamping capabilities. > > Fixes: a0d2f20650e8 ("Renesas Ethernet AVB PTP clock driver") > Cc: stable@vger.kernel.org > Signed-off-by: Xuanqiang Luo > --- > drivers/net/ethernet/renesas/ravb_main.c | 3 ++- > drivers/net/ethernet/renesas/ravb_ptp.c | 12 ++++++++++-- > 2 files changed, 12 insertions(+), 3 deletions(-) > > diff --git a/drivers/net/ethernet/renesas/ravb_main.c b/drivers/net/ethernet/renesas/ravb_main.c > index 5f88733094d0f..3a9d9f8718216 100644 > --- a/drivers/net/ethernet/renesas/ravb_main.c > +++ b/drivers/net/ethernet/renesas/ravb_main.c > @@ -1779,7 +1779,8 @@ static int ravb_get_ts_info(struct net_device *ndev, > (1 << HWTSTAMP_FILTER_NONE) | > (1 << HWTSTAMP_FILTER_PTP_V2_L2_EVENT) | > (1 << HWTSTAMP_FILTER_ALL); > - info->phc_index = ptp_clock_index(priv->ptp.clock); > + if (priv->ptp.clock) > + info->phc_index = ptp_clock_index(priv->ptp.clock); > } > > return 0; > diff --git a/drivers/net/ethernet/renesas/ravb_ptp.c b/drivers/net/ethernet/renesas/ravb_ptp.c > index 226c6c0ab945b..eaf07cb8eadfa 100644 > --- a/drivers/net/ethernet/renesas/ravb_ptp.c > +++ b/drivers/net/ethernet/renesas/ravb_ptp.c > @@ -315,6 +315,7 @@ void ravb_ptp_interrupt(struct net_device *ndev) > void ravb_ptp_init(struct net_device *ndev, struct platform_device *pdev) > { > struct ravb_private *priv = netdev_priv(ndev); > + struct ptp_clock *clock; > unsigned long flags; > > priv->ptp.info = ravb_ptp_info; > @@ -327,7 +328,13 @@ void ravb_ptp_init(struct net_device *ndev, struct platform_device *pdev) > ravb_modify(ndev, GCCR, GCCR_TCSS, GCCR_TCSS_ADJGPTP); > spin_unlock_irqrestore(&priv->lock, flags); > > - priv->ptp.clock = ptp_clock_register(&priv->ptp.info, &pdev->dev); > + clock = ptp_clock_register(&priv->ptp.info, &pdev->dev); > + if (IS_ERR(clock)) { > + netdev_err(ndev, "failed to register PTP clock: %pe\n", clock); > + clock = NULL; > + } > + > + priv->ptp.clock = clock; > } > > void ravb_ptp_stop(struct net_device *ndev) > @@ -337,5 +344,6 @@ void ravb_ptp_stop(struct net_device *ndev) > ravb_write(ndev, 0, GIC); > ravb_write(ndev, 0, GIS); > > - ptp_clock_unregister(priv->ptp.clock); > + if (priv->ptp.clock) > + ptp_clock_unregister(priv->ptp.clock); > } Reviewed-by: Vadim Fedorenko