From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mslow1.mail.gandi.net (mslow1.mail.gandi.net [217.70.178.240]) (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 7A29D1CF280; Wed, 4 Sep 2024 10:53:31 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.70.178.240 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1725447214; cv=none; b=kRfmvcawTgIV2u0H/lzMhk5cSu+I+1EHSyPk93vPgngVeCqFbaDPqVzplA4hFe/WZZ6Jy6KnfJBv3dLfSrQaYjYPMaFWnG/0QCj6ZmvgBuIaJs5KaUJK8oDWTrszcUL07WRitfatoIsZX5GtIVYPtANj5TlIXvyMeJWdoBCG4zw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1725447214; c=relaxed/simple; bh=IAvCk1yjCPWRHhJhJZGE3McWze1Xp4mYQh62iJBq51I=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=bxLUr67GnHaY9s64bapNMdvk5HhaCQmYieh8bCHRoQtyImK+M8Omj7XFCjMb++dfmt/qH1FDS4x+K1LU0DvluTAS38NTjkcpYfATr6JMFFo4DegPn8zj2DDfGT3KwLCj5SLIAQGRphQmSDsNihoTjZLpjo23Zl3VUNBhMSH6OgI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=bootlin.com; spf=pass smtp.mailfrom=bootlin.com; dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com header.b=AjO+zJcz; arc=none smtp.client-ip=217.70.178.240 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=bootlin.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=bootlin.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com header.b="AjO+zJcz" Received: from relay8-d.mail.gandi.net (unknown [IPv6:2001:4b98:dc4:8::228]) by mslow1.mail.gandi.net (Postfix) with ESMTP id C278EC37F8; Wed, 4 Sep 2024 10:49:59 +0000 (UTC) Received: by mail.gandi.net (Postfix) with ESMTPSA id 805841BF206; Wed, 4 Sep 2024 10:49:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=gm1; t=1725446992; 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=OlQwp//l7+YMqCwEc62IbsKJVaVaIN0kbujxzcaSERM=; b=AjO+zJczyrIU9K82FhJ8IfAofM+yJtFx1/tB0Usq8CuxFJmN/lqMvG7f4uaUqRzzKIg32Y 072cQqb2AYT+TcGFLby8CWj4hKXnCXptPUgIIXJ1a8KYaP8UNSiIFSV52DXfCMuy7V8Jbd 67ZvV/uH0AlmbJ81czvB2WNIuDTpqwhNrOm2OUUojHecup2yvlEtUGdmNT6GUyJd3JihgY GjBlIAQUEwsCJoElvHxaqzCoGfd5HvX/ZgCtb3r5sM9HKrd/Y1q+k3RXuoL3bUPtv+xFt6 RCfqul/llDwO58QjXYaEAQJF0+rROiGIUJskuUOfy9c8UGZN1Z7qFCCkeJHrCA== Date: Wed, 4 Sep 2024 12:49:49 +0200 From: Maxime Chevallier To: Jakub Kicinski Cc: davem@davemloft.net, Pantelis Antoniou , Andrew Lunn , Eric Dumazet , Paolo Abeni , Russell King , Christophe Leroy , Florian Fainelli , Heiner Kallweit , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, thomas.petazzoni@bootlin.com, Herve Codina , Simon Horman , linuxppc-dev@lists.ozlabs.org Subject: Re: [PATCH net-next v2 7/7] net: ethernet: fs_enet: phylink conversion Message-ID: <20240904124949.563f1343@fedora.home> In-Reply-To: <20240902185543.48d91e87@kernel.org> References: <20240829161531.610874-1-maxime.chevallier@bootlin.com> <20240829161531.610874-8-maxime.chevallier@bootlin.com> <20240902185543.48d91e87@kernel.org> Organization: Bootlin X-Mailer: Claws Mail 4.3.0 (GTK 3.24.43; x86_64-redhat-linux-gnu) Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-GND-Sasl: maxime.chevallier@bootlin.com Hi Jakub, On Mon, 2 Sep 2024 18:55:43 -0700 Jakub Kicinski wrote: > On Thu, 29 Aug 2024 18:15:30 +0200 Maxime Chevallier wrote: > > @@ -582,15 +591,12 @@ static void fs_timeout_work(struct work_struct *work) > > > > dev->stats.tx_errors++; > > > > - spin_lock_irqsave(&fep->lock, flags); > > - > > - if (dev->flags & IFF_UP) { > > - phy_stop(dev->phydev); > > - (*fep->ops->stop)(dev); > > - (*fep->ops->restart)(dev); > > - } > > + rtnl_lock(); > > so we take rtnl_lock here.. > > > + phylink_stop(fep->phylink); > > + phylink_start(fep->phylink); > > + rtnl_unlock(); > > > > - phy_start(dev->phydev); > > + spin_lock_irqsave(&fep->lock, flags); > > wake = fep->tx_free >= MAX_SKB_FRAGS && > > !(CBDR_SC(fep->cur_tx) & BD_ENET_TX_READY); > > spin_unlock_irqrestore(&fep->lock, flags); > > > @@ -717,19 +686,18 @@ static int fs_enet_close(struct net_device *dev) > > unsigned long flags; > > > > netif_stop_queue(dev); > > - netif_carrier_off(dev); > > napi_disable(&fep->napi); > > cancel_work_sync(&fep->timeout_work); > > ..and cancel_work_sync() under rtnl_lock here? > > IDK if removing the the "dev->flags & IFF_UP" check counts as > meaningfully making it worse, but we're going in the wrong direction. > The _sync() has to go, and the timeout work needs to check if device > has been closed under rtnl_lock ? Arg that's true, I didn't consider that call path at all... Sorry about that, I'll indeed rework that to address this deadlock waiting to happen. Thanks, Maxime