From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.18]) (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 1FD5617B418; Wed, 31 Dec 2025 06:03:37 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=192.198.163.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1767161020; cv=none; b=BOqpJrqye2NpI1ipUaef5tiQ1nxaGDTJViKa0rKmC5UXtgGNF16B4HcQZs9FjC0T5bWJ1SGHAycedFOwJsjZcDoRaZwDr4jEJ8fh6fYR0S/hG5fd80319ucOKu4wVLRqKc/awEITEkjviz+dnGKqGG/WMpWJ1blkoxwCp30lxC4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1767161020; c=relaxed/simple; bh=JxKBMVA0V5En0PF99ldHeVfhN5tl7ryf6LylUk3YPH0=; h=Date:From:To:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=PbjiOTlUoxq/FXJ6gGY8hx631zX2xJoMD8hT0CZtX+LweuUiKb22jyd5w+9v/gNoCKNXDrAXh31AW0xim+mdsBEE+d8Tkx9WP7DictErDKwVsl5VwrdhvKy7n/avnbQg8fRSyHyoXmuMJJrPizjd9FOOKE3CGjidRejAEgetwec= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com; spf=pass smtp.mailfrom=linux.intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=DfcsVcG7; arc=none smtp.client-ip=192.198.163.18 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="DfcsVcG7" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1767161018; x=1798697018; h=date:from:to:subject:message-id:references:mime-version: in-reply-to; bh=JxKBMVA0V5En0PF99ldHeVfhN5tl7ryf6LylUk3YPH0=; b=DfcsVcG7K19ZSQzMXtxfXDzan+TFShSWz6DqFnxi/CbSTVNb7CGDCLwM 8qXcTEn+yro0ZLaddmGxuHzSZP7ZG39sKDMbTGaiNT0clQzRsEz24uyU9 QK8/w7P0tYDloCKMK2FZww2K9O0AUV7B215QuRjUcrr8YCvkMfH8dp7bx x2Pc85XdXSfqu3uXv12AyZqtnNDbmhqSy68e0TRdfg/Q7uhTrViHxjg5f e1BO/ybHp6R+VOPFgTNK4fSeopVRqQoP6fmdJ8j+cNX7k2Zvsx14r5IPJ NlWtBQ0wEl8lbHyYnuw+iqcx7v9p2yM5I9F1CibDTIlZIp41xnn1TfMBW w==; X-CSE-ConnectionGUID: Pk17Q9ItT9y+mEYAqe+/QQ== X-CSE-MsgGUID: pVX1gueQQiK0W3HmhCVXJg== X-IronPort-AV: E=McAfee;i="6800,10657,11657"; a="67931763" X-IronPort-AV: E=Sophos;i="6.21,191,1763452800"; d="scan'208";a="67931763" Received: from fmviesa004.fm.intel.com ([10.60.135.144]) by fmvoesa112.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 30 Dec 2025 22:03:37 -0800 X-CSE-ConnectionGUID: aEnB+OVxTeqg19rv12ubhQ== X-CSE-MsgGUID: qd1vSFf4RvWNYKmn2rAxyw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.21,191,1763452800"; d="scan'208";a="206254320" Received: from black.igk.intel.com ([10.91.253.5]) by fmviesa004.fm.intel.com with ESMTP; 30 Dec 2025 22:03:35 -0800 Received: by black.igk.intel.com (Postfix, from userid 1001) id AB9DC8E; Wed, 31 Dec 2025 07:03:33 +0100 (CET) Date: Wed, 31 Dec 2025 07:03:33 +0100 From: Mika Westerberg To: "Chia-Lin Kao (AceLan)" , Mario Limonciello , Andreas Noever , Mika Westerberg , Yehezkel Bernat , linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, Sanath.S@amd.com, "Lin, Wayne" Subject: Re: [PATCH] [RFC] thunderbolt: Add delay for Dell U2725QE link width Message-ID: <20251231060333.GK2275908@black.igk.intel.com> References: <20251217125507.GR2275908@black.igk.intel.com> <5d7f2661-f02b-4985-b438-196b48c10237@amd.com> <20251218072125.GU2275908@black.igk.intel.com> <6inne3luvw4ot3wqnsaw3gzhlxtd4756i465oto6so5ox3syxp@kibuv4vhvexx> <20251218102021.GV2275908@black.igk.intel.com> <20251230073011.GD2275908@black.igk.intel.com> <7u6z5gp5ma2jg5zzxniupu4zuipjgxgnjydltx5cntikjtf3ww@qb62nuy7jsfk> 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=utf-8 Content-Disposition: inline In-Reply-To: <7u6z5gp5ma2jg5zzxniupu4zuipjgxgnjydltx5cntikjtf3ww@qb62nuy7jsfk> On Wed, Dec 31, 2025 at 09:33:15AM +0800, Chia-Lin Kao (AceLan) wrote: > On Tue, Dec 30, 2025 at 08:30:11AM +0100, Mika Westerberg wrote: > > On Mon, Dec 22, 2025 at 09:33:48AM +0800, Chia-Lin Kao (AceLan) wrote: > > > On Thu, Dec 18, 2025 at 11:20:21AM +0100, Mika Westerberg wrote: > > > > On Thu, Dec 18, 2025 at 03:35:05PM +0800, Chia-Lin Kao (AceLan) wrote: > > > > > > Now since USB 2.x has its own wires in Type-C cable this tells me that > > > > > > there is some real problem with the connection. Have you tried different > > > > > > cables already? > > > > > Here is the log I got with another tbt4 cable. > > > > > I'm using the kernel with Mario suggests modification. > > > > > > > > > > https://people.canonical.com/~acelan/bugs/tbt_call_trace/intel/merged_6.18.0-d358e5254674+.patched2.2_new_cable.out > > > > > > > > Here I see (assuming I read it right) that the USB 2.x enumerates only > > > > after the first unplug: > > > > > > > > [ 28.589861] usb 3-2: New USB device found, idVendor=1d5c, idProduct=5801, bcdDevice= 1.01 > > > > [ 28.589864] usb 3-2: New USB device strings: Mfr=1, Product=2, SerialNumber=0 > > > > [ 28.589865] usb 3-2: Product: USB2.0 Hub > > > > [ 28.589866] usb 3-2: Manufacturer: Fresco Logic, Inc. > > > >From the logs, sometimes this hub is enumerated before the call trace > > > and then enumerated again after the call trace. > > > > > > And I also found there are some suspicious USB disconnections while > > > plugging in the tbt monitor. > > > > > > I tried to avoid the USB disconnection by the following modification, > > > but still no luck. > > > > Okay but I think this is not a SW issue, rather an issue with that > > particular monitor/cable/connection/PD. It is not just the USB4 link that > > goes down it's the whole type-C connection therefore something is wrong on > > the electrical side of things (well at least it seems so). > If that's the case, would you agree to suppress the scary call trace > like this? > > diff --git a/drivers/thunderbolt/path.c b/drivers/thunderbolt/path.c > index f9b11dadfbdd..ae7127eca542 100644 > --- a/drivers/thunderbolt/path.c > +++ b/drivers/thunderbolt/path.c > @@ -586,7 +586,18 @@ int tb_path_activate(struct tb_path *path) > tb_dbg(path->tb, "%s path activation complete\n", path->name); > return 0; > err: > - tb_WARN(path->tb, "%s path activation failed\n", path->name); > + /* > + * -ENOTCONN can occur during transient hardware states like lane > + * bonding or when the Type-C connection has electrical issues. The > + * hardware may automatically retry by reconnecting. Use a regular > + * warning instead of tb_WARN to avoid generating call traces for > + * these expected transient conditions. > + */ > + if (res == -ENOTCONN) > + tb_warn(path->tb, "%s path activation failed (port not connected)\n", > + path->name); > + else > + tb_WARN(path->tb, "%s path activation failed\n", path->name); > return res; > } Yes please but make it unconditionally do tb_warn() instead of that tb_WARN(). > > Dell also typically validate that their stuff works in Linux so I would > > expect to got some report from them if that's not the case (unless you are > > doing just that ;-)) > Currently, the issue could be reproduced on the AMD platform every > time when plugging in the tbt monitor. We don't report the issue on > Intel platform yet, because of it's low failrate. > And the issue is not critical, as it can be recovered after > re-enumerating the monitor. > So maybe they won't bother you about this issue. You only have one of those monitors? It would be good to check with another if it has the same issue. I have GR reference device here which is what this monitor is based on but I don't see any unplugs or link issues. I will ask around if we have somewhere this monitor.