From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from metis.whiteo.stw.pengutronix.de (metis.whiteo.stw.pengutronix.de [185.203.201.7]) (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 C424824E4C6 for ; Wed, 10 Sep 2025 04:17:01 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=185.203.201.7 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1757477824; cv=none; b=hJQf7k7DduR3WfP1375O5Z8jCxtUqpnCdpxgdqPjYj3E1SwTwkd3boOjLbX6sMHR7MTLDd2J7R+WgnippxXwbijjfIUjHmwPp99UgYM3rCXLOSDyKpmrZmjxBzdUuAYshKj7Utp+4cqN/HotLU5Aqy4A18+vnvIW9giYm2LQWRk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1757477824; c=relaxed/simple; bh=w0W3KNjsi/GHJVWcfix9W6ySCaUXQgtzSg/5Pkb/yZY=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=M60O48/1g2OHO9Grahnj+uQQ/uXy4uA+hvZtYhORTCJC4+7HZs7MlPALainyAjhh08UnrZEaprF5Vh2yhc19e5J/fNZ64frINAoDOQ+b2JMrXFXWe3ZseRvEYnKkbTSnhy+2jB0nDE4b4sIgkjxkDgszY31tSDuXqF6dWYCODTU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=pengutronix.de; spf=pass smtp.mailfrom=pengutronix.de; arc=none smtp.client-ip=185.203.201.7 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=pengutronix.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=pengutronix.de Received: from drehscheibe.grey.stw.pengutronix.de ([2a0a:edc0:0:c01:1d::a2]) by metis.whiteo.stw.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1uwCGH-0003hM-82; Wed, 10 Sep 2025 06:16:49 +0200 Received: from pty.whiteo.stw.pengutronix.de ([2a0a:edc0:2:b01:1d::c5]) by drehscheibe.grey.stw.pengutronix.de with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.96) (envelope-from ) id 1uwCGG-000X4t-2J; Wed, 10 Sep 2025 06:16:48 +0200 Received: from ore by pty.whiteo.stw.pengutronix.de with local (Exim 4.96) (envelope-from ) id 1uwCGG-00G74b-1q; Wed, 10 Sep 2025 06:16:48 +0200 Date: Wed, 10 Sep 2025 06:16:48 +0200 From: Oleksij Rempel To: Jakub Kicinski Cc: Hubert =?utf-8?Q?Wi=C5=9Bniewski?= , Andrew Lunn , "David S. Miller" , Eric Dumazet , Paolo Abeni , stable@vger.kernel.org, kernel@pengutronix.de, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, Lukas Wunner , Russell King , Xu Yang , linux-usb@vger.kernel.org Subject: Re: [PATCH net v1 1/1] net: usb: asix: ax88772: drop phylink use in PM to avoid MDIO runtime PM wakeups Message-ID: References: <20250908112619.2900723-1-o.rempel@pengutronix.de> <20250909165645.755e52f6@kernel.org> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20250909165645.755e52f6@kernel.org> X-Sent-From: Pengutronix Hildesheim X-URL: http://www.pengutronix.de/ X-Accept-Language: de,en X-Accept-Content-Type: text/plain X-SA-Exim-Connect-IP: 2a0a:edc0:0:c01:1d::a2 X-SA-Exim-Mail-From: ore@pengutronix.de X-SA-Exim-Scanned: No (on metis.whiteo.stw.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: netdev@vger.kernel.org On Tue, Sep 09, 2025 at 04:56:45PM -0700, Jakub Kicinski wrote: > On Tue, 9 Sep 2025 09:17:17 +0200 Oleksij Rempel wrote: > > > > Fixes: e0bffe3e6894 ("net: asix: ax88772: migrate to phylink") > > > > > > It does, but v5.15 (including v5.15.191 LTS) is affected as well, from > > > 4a2c7217cd5a ("net: usb: asix: ax88772: manage PHY PM from MAC"). I think > > > it could also use a patch, but I won't insist. > > > > Ack, I'll try do address it later. > > Any idea what the problem is there? Deadlocking on a different lock? Yes, it is PM lock taken in MDIO access inside of PM routine. We can't reliably detect a PM context from MDIO bus read/write calls. Taking local counters or setting flags would partially work, but they all are not safe against race conditions. -- Pengutronix e.K. | | Steuerwalder Str. 21 | http://www.pengutronix.de/ | 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |