From mboxrd@z Thu Jan 1 00:00:00 1970 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 384D4ECAAA1 for ; Mon, 12 Sep 2022 10:38:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229585AbiILKiz (ORCPT ); Mon, 12 Sep 2022 06:38:55 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37504 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229496AbiILKiy (ORCPT ); Mon, 12 Sep 2022 06:38:54 -0400 Received: from metis.ext.pengutronix.de (metis.ext.pengutronix.de [IPv6:2001:67c:670:201:290:27ff:fe1d:cc33]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EC8372124B for ; Mon, 12 Sep 2022 03:38:53 -0700 (PDT) Received: from gallifrey.ext.pengutronix.de ([2001:67c:670:201:5054:ff:fe8d:eefb] helo=bjornoya.blackshift.org) by metis.ext.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1oXgpi-0007Ch-Fz; Mon, 12 Sep 2022 12:38:30 +0200 Received: from pengutronix.de (unknown [IPv6:2a03:f580:87bc:d400:75e7:62d4:691e:2f47]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (P-256) server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) (Authenticated sender: mkl-all@blackshift.org) by smtp.blackshift.org (Postfix) with ESMTPSA id 2F4DAE120B; Mon, 12 Sep 2022 10:38:27 +0000 (UTC) Date: Mon, 12 Sep 2022 12:38:18 +0200 From: Marc Kleine-Budde To: Bence =?utf-8?B?Q3PDs2vDoXM=?= Cc: netdev@vger.kernel.org, Richard Cochran , "David S . Miller" , Jakub Kicinski , Francesco Dolcini , Andrew Lunn , Guenter Roeck , kernel@pengutronix.de, =?utf-8?B?Q3PDs2vDoXM=?= Bence Subject: Re: [PATCH 1/2] Revert "net: fec: Use a spinlock to guard `fep->ptp_clk_on`" Message-ID: <20220912103818.j2u6afz66tcxvnr6@pengutronix.de> References: <20220912073106.2544207-1-bence98@sch.bme.hu> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="bkeskyh3bgpjqw4a" Content-Disposition: inline In-Reply-To: <20220912073106.2544207-1-bence98@sch.bme.hu> X-SA-Exim-Connect-IP: 2001:67c:670:201:5054:ff:fe8d:eefb X-SA-Exim-Mail-From: mkl@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: netdev@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org --bkeskyh3bgpjqw4a Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On 12.09.2022 07:31:04, Bence Cs=C3=B3k=C3=A1s wrote: > From: Cs=C3=B3k=C3=A1s Bence >=20 > `clk_prepare_enable()` gets called in atomic context (holding a spinlock), > which may sleep, causing a BUG on certain platforms. >=20 > This reverts commit b353b241f1eb9b6265358ffbe2632fdcb563354f. >=20 > Reported-by: Marc Kleine-Budde > Link: https://lore.kernel.org/all/20220907143915.5w65kainpykfobte@pengutr= onix.de/ > Signed-off-by: Cs=C3=B3k=C3=A1s Bence This is not a 100% revert. In b353b241f1eb ("net: fec: Use a spinlock to guard `fep->ptp_clk_on`") the "struct fec_enet_private *fep" was renamed to "struct fec_enet_private *adapter" for no apparent reason. The driver uses "fep" everywhere else. This revert doesn't restore the original state. This leads to the following diff against a 100% revert. diff --git a/drivers/net/ethernet/freescale/fec_ptp.c b/drivers/net/etherne= t/freescale/fec_ptp.c index c99dff3c3422..c74d04f4b2fd 100644 --- a/drivers/net/ethernet/freescale/fec_ptp.c +++ b/drivers/net/ethernet/freescale/fec_ptp.c @@ -365,21 +365,21 @@ static int fec_ptp_adjtime(struct ptp_clock_info *ptp= , s64 delta) */ static int fec_ptp_gettime(struct ptp_clock_info *ptp, struct timespec64 *= ts) { - struct fec_enet_private *fep =3D + struct fec_enet_private *adapter =3D container_of(ptp, struct fec_enet_private, ptp_caps); u64 ns; unsigned long flags; =20 - mutex_lock(&fep->ptp_clk_mutex); + mutex_lock(&adapter->ptp_clk_mutex); /* Check the ptp clock */ - if (!fep->ptp_clk_on) { - mutex_unlock(&fep->ptp_clk_mutex); + if (!adapter->ptp_clk_on) { + mutex_unlock(&adapter->ptp_clk_mutex); return -EINVAL; } - spin_lock_irqsave(&fep->tmreg_lock, flags); - ns =3D timecounter_read(&fep->tc); - spin_unlock_irqrestore(&fep->tmreg_lock, flags); - mutex_unlock(&fep->ptp_clk_mutex); + spin_lock_irqsave(&adapter->tmreg_lock, flags); + ns =3D timecounter_read(&adapter->tc); + spin_unlock_irqrestore(&adapter->tmreg_lock, flags); + mutex_unlock(&adapter->ptp_clk_mutex); =20 *ts =3D ns_to_timespec64(ns); regards, Marc --=20 Pengutronix e.K. | Marc Kleine-Budde | Embedded Linux | https://www.pengutronix.de | Vertretung West/Dortmund | Phone: +49-231-2826-924 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 | --bkeskyh3bgpjqw4a Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAABCgAdFiEEBsvAIBsPu6mG7thcrX5LkNig010FAmMfDBcACgkQrX5LkNig 010Ywgf/f6P/2XH6p6BGMFzve/yJDWkBFEruig1JimoGDkRok897UmyDOewsveA4 nlFBwio6+u6S322ZJklup+pV0ea/iALtHYP1G/EEnpPFCjr1Y8MULNsm6r/OdLrN DOlH/BPQmzPJrGk9uiSrnNCfXP7t7S280fuPn4UqMG53q0oIJus/mFWvNgwGx5qZ 1PUDPNQS+Ux4Xb60LyLZ3QpGSmejYIAsOKLyHAqUYLB7Z+CRIVW3p4OEb+tq/3kG Gdd2EXUKuh7wE39sU8bymMO+Z7Np8l2XvXl5IHhbXBf6YvIcOYS3/RdGiTDW4Jat 2AOFiQjVJqVMNmsiIVNwl1WlJtCEGw== =kR2t -----END PGP SIGNATURE----- --bkeskyh3bgpjqw4a--