From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 4F32F5625E5 for ; Thu, 10 Sep 2026 17:31:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789061520; cv=none; b=Ak+HF8vwO02+98y9qQUg4Yl0HyunSdqAa9c03Yl4ygWQuI5O23nE4CChhqVlloQALqBZyNq8UUicLMHjY8d816kQ4d/moAAaGJ8tEhpeRjBATW1pfayrKYfMSlxEL9cqmsEepXYRZHAp2WJpeyQJAO6KchgcJDUZhGvLq8kWFn4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789061520; c=relaxed/simple; bh=wzZC/dKazyZ1Tje9II7fUSdS2MC2evOutVZM6TU2K5g=; h=From:Subject:To:Cc:In-Reply-To:References:Content-Type:Date: Message-Id; b=W8rZYam+tyS2QNlFCi3QChQXEizk4T4xR6U65zHCJf7y/ilp4itg1zqTn07MBn4jKpTUfK3pqak35u2wMlpRo0YsELiiD7nFeFPTpi4OU4E9zrJJKajgSyWo/pENOwVd3lIQwwBHVuZYsQeI7HwPZ64Cik3Wt3Dx5tNd8xvuSkU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=HCQHwHOp; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="HCQHwHOp" Received: by smtp.kernel.org (Postfix) with ESMTPSA id ADF991F00899; Thu, 10 Sep 2026 17:31:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1789061504; bh=UZZnhFDcoitetkwTJCJMqFv1JiV9WcQb7vVYt0Kknt4=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=HCQHwHOpphR9xBetn7L7jIViNnssejzw3fBFLZZpvHPKlMl2YYBrsjAstDDPX50Nb tyNy2JgFz8TzcNFjV0ueN2EL1DsXG6MYE9AwE8rRxVeUSXY0hCSwVKtEe8lZNx5t4Q WUoAS/o/UaUgim5sJW+125v2MlOdiU/xQmQLn+uQQ6ybjZzvU/04Z44Z4dbbVW+KuA Y48sHm4QSB/jOoR3CEFd9iIBshbRpK181gIDFRmEW8lhIp0Em1LSydBCw+zGuY1K5k 4fV7u2qHpbpsce7ES+nGLGC5vtckrfPu4nZSLzT3G8ICnAFD53dCRrYgj6V8cOEu+J XB2YYL8XawMWg== From: sashiko-bot@kernel.org Subject: Re: [PATCH net-next v4 05/10] net: ethernet: ravb: Propagate error from ptp_clock_register() Reply-To: sashiko-reviews@lists.linux.dev To: =?utf-8?b?TmlrbGFzIFPDtmRlcmx1bmQ=?= Cc: wsa+renesas@sang-engineering.com, conor+dt@kernel.org, devicetree@vger.kernel.org, robh@kernel.org In-Reply-To: <20260909173027.2201560-6-niklas.soderlund+renesas@ragnatech.se> References: <20260909173027.2201560-1-niklas.soderlund+renesas@ragnatech.se> <20260909173027.2201560-6-niklas.soderlund+renesas@ragnatech.se> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Thu, 10 Sep 2026 17:31:43 +0000 Message-Id: <20260910173143.ADF991F00899@smtp.kernel.org> Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Thank you for your contribution! Sashiko AI review found 1 potential issue(= s) to consider: - [Medium] Missing WRITE_ONCE and temporary exposure of ERR_PTR in a lockle= ssly accessed variable. -- commit b7840c35cf3291bc3d465af40f2ae38cc9f5f972 Author: Niklas S=C3=B6derlund net: ethernet: ravb: Propagate error from ptp_clock_register() This commit reworks ravb_ptp_init() to check the return value of ptp_clock_register() and propagate any errors back to the caller. It also refactors the clock assignment by removing the intermediate local variable. Link: https://sashiko.dev/#/patchset/20260610102432.3538432-2-niklas.soderl= und+renesas@ragnatech.se?part=3D1 > diff --git a/drivers/net/ethernet/renesas/ravb_ptp.c b/drivers/net/ethern= et/renesas/ravb_ptp.c > index f70b616ac847c..37161c0579ce7 100644 > --- a/drivers/net/ethernet/renesas/ravb_ptp.c > +++ b/drivers/net/ethernet/renesas/ravb_ptp.c [ ... ] > -void ravb_ptp_init(struct net_device *ndev) > +int ravb_ptp_init(struct net_device *ndev) > { > struct ravb_private *priv =3D netdev_priv(ndev); > - struct ptp_clock *clock; > unsigned long flags; > + int ret =3D 0; > =20 > priv->ptp.info =3D ravb_ptp_info; > =20 [ ... ] > - clock =3D ptp_clock_register(&priv->ptp.info, &priv->pdev->dev); > - if (IS_ERR(clock)) { > - netdev_err(ndev, "failed to register PTP clock: %pe\n", clock); > - clock =3D NULL; > + priv->ptp.clock =3D ptp_clock_register(&priv->ptp.info, &priv->pdev->de= v); > + if (IS_ERR(priv->ptp.clock)) { > + ret =3D PTR_ERR(priv->ptp.clock); > + priv->ptp.clock =3D NULL; > + ravb_ptp_stop(ndev); > } > =20 > - WRITE_ONCE(priv->ptp.clock, clock); > - if (clock) > - WRITE_ONCE(priv->ptp.phc_index, ptp_clock_index(clock)); > + return ret; > } [Severity: Medium] Does this introduce a data race by directly publishing an invalid pointer? The ravb_ptp_interrupt() handler accesses priv->ptp.clock locklessly via READ_ONCE(). Because the interrupt handler is registered and enabled via ravb_setup_irq() before ravb_ptp_init() runs, the hardware interrupt might already be firing when we reach this point. If ptp_clock_register() fails, it returns an ERR_PTR. By assigning it directly to priv->ptp.clock without WRITE_ONCE(), we could have a scenario where an interrupt fires immediately after the assignment, but before the error check clears priv->ptp.clock to NULL. The interrupt handler in ravb_ptp_interrupt() would then read the ERR_PTR: struct ptp_clock *clock =3D READ_ONCE(priv->ptp.clock); ... if ((gis & GIS_PTCF) && clock) { ... ptp_clock_event(clock, &event); Could this crash by dereferencing the ERR_PTR? Would it be safer to restore the original local variable pattern and retain the WRITE_ONCE() so that priv->ptp.clock only ever sees a valid pointer or NULL? --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/20260909173027.2201= 560-1-niklas.soderlund+renesas@ragnatech.se?part=3D5