From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from vps0.lunn.ch (vps0.lunn.ch [156.67.10.101]) (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 6086F246762; Fri, 28 Aug 2026 15:15:35 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=156.67.10.101 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787930137; cv=none; b=W7f8yBoPerTpbTTweL+flvqTgDuBKCKARbTpFyBDE9spkfa/SipzxEdhn9rJ3N6l68aixuLl1FHtTYxuiu3s0tqmmlwtbJT0LOJ9U7Z0FK8F5a8W5rdkl6wh1nLJeyUsmHP/oTJts6pWpcoT0McFZtku5l4NEvSg3M83gTBxbJg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787930137; c=relaxed/simple; bh=vHM7IuyBYqU+aanM6T9n5z+27YmsvMatP4sTu9IDIVQ=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=VLBUR8QBGUQLs+tSZOShJU90ckX2xk39Zcz3f1C4HflSrKhFnjoEFdOPW77k7Jkip1MLPsLvddNzQrPmDfP3DxFH7+sYqb7y7juyW0+Y+xvP0PnIdB+lCtaN0pT6HlIH7lwF7zFB/uiwwgnaJIo7cIw4lM5loRA1rtvQFTODoA4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=lunn.ch; spf=pass smtp.mailfrom=lunn.ch; dkim=pass (1024-bit key) header.d=lunn.ch header.i=@lunn.ch header.b=eh0ELsyP; arc=none smtp.client-ip=156.67.10.101 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=lunn.ch Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=lunn.ch Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=lunn.ch header.i=@lunn.ch header.b="eh0ELsyP" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lunn.ch; s=20171124; h=In-Reply-To:Content-Disposition:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:From:Sender:Reply-To:Subject: Date:Message-ID:To:Cc:MIME-Version:Content-Type:Content-Transfer-Encoding: Content-ID:Content-Description:Content-Disposition:In-Reply-To:References; bh=6SkOmdvoiBqKfQ+sV84Hc+Uue6acCGOEhTyi6KmwzcE=; b=eh0ELsyPIb23kpIE0hDOnUu2oX FyHQv6MYEIL52keZa60gVvbLPfPJo9Dt9YZOTRgjnEkbgh6Ob6idFvhoL8p1jDVC8LWbExWCpGd/u lIwNOsE8KHELjRcozypECl+SJe3l0MmVNjiM2IBX+IfssjTFn51I6FBtctClAr13laKk=; Received: from andrew by vps0.lunn.ch with local (Exim 4.94.2) (envelope-from ) id 1wzyId-001pR5-5c; Fri, 28 Aug 2026 17:15:23 +0200 Date: Fri, 28 Aug 2026 17:15:23 +0200 From: Andrew Lunn To: Farhad Alemi Cc: Heiner Kallweit , Andrew Lunn , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , falemi@asu.edu, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [BUG] _phy_state_machine / phy_stop -- a USB PHY that reports an MDIO error to phylib panics a panic_on_warn kernel Message-ID: <63bfddae-b456-4645-b992-e730bdd4b1ac@lunn.ch> References: Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Thu, Aug 27, 2026 at 10:29:36PM -0700, Farhad Alemi wrote: > Hello, > > As part of the kernel research at ASU's SEFCOM > lab, we hit the crash below. Crash reports can be found here: > > https://github.com/farhad-alemi/public_bug_reports/tree/main/146-phylib-phy_error-warn_on-mdio-error/ > > smsc95xx 6-1:1.0 eth0: Error reading MII_ACCESS > smsc95xx 6-1:1.0 eth0: smsc95xx_mdio_read: MII is busy > _phy_start_aneg+0x0/0x480: returned: -32 > WARNING: drivers/net/phy/phy.c:1352 at phy_error_precise > drivers/net/phy/phy.c:1352 [inline], CPU#0: kworker/0:3/5063 > WARNING: drivers/net/phy/phy.c:1352 at > _phy_state_machine+0x667/0xf20 drivers/net/phy/phy.c:1613, CPU#0: > kworker/0:3/5063 > Modules linked in: > CPU: 0 UID: 0 PID: 5063 Comm: kworker/0:3 Not tainted 7.1.0-rc5 #1 > PREEMPT(full) > Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS > 1.16.3-debian-1.16.3-2 04/01/2014 > Workqueue: events_power_efficient phy_state_machine > RIP: 0010:phy_error_precise drivers/net/phy/phy.c:1352 [inline] > RIP: 0010:_phy_state_machine+0x66d/0xf20 drivers/net/phy/phy.c:1613 > Call Trace: > > phy_state_machine+0x2b/0x70 drivers/net/phy/phy.c:1652 > process_one_work kernel/workqueue.c:3314 [inline] > process_scheduled_works+0x881/0x1170 kernel/workqueue.c:3397 > worker_thread+0x988/0xde0 kernel/workqueue.c:3478 > kthread+0x333/0x420 kernel/kthread.c:436 > ret_from_fork+0x351/0x940 arch/x86/kernel/process.c:158 > ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 > Could you point out the crash here? I don't see a crash. Andrew