From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.18]) (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 00652390236; Mon, 23 Mar 2026 11:03:04 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.175.65.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774263786; cv=none; b=rWlOEWVMw4VFUD16y1dD1xw86Xsq3eY639tr5fz9EV325NRmENzPROyslWbAyRjzaRu2bS7+sSMsCp4Lju+Aw3vgtVNGw1egFNeUdSI+Ics7qsVUcZbHMDNcU/zhR1oZAZQ96ExXhfZZoOre7adYmoTMVs3uIo6hB3fzzXMz450= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774263786; c=relaxed/simple; bh=lwzszmN0gUEL/hG6F2iaX0s8NeEJgFur5NjFkR20Uys=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=pgOClanDl+IdpwoqzM2kk0lNoFarYzoMmVcDP3KOclcE4iUGW3Lo9VZbN9F3O9RHea4aurF43OeyNC/EmLgx+i7cPtnHnP6NrSaE2KhSOE0Lobte+JsnkIYPggDZFvLxUIgEIPLYPMHCsIncK2a0PBvOnMaIQEP4gZ4O4t9LaGE= 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=JSTw/RLw; arc=none smtp.client-ip=198.175.65.18 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="JSTw/RLw" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1774263785; x=1805799785; h=date:from:to:cc:subject:message-id:references: mime-version:in-reply-to; bh=lwzszmN0gUEL/hG6F2iaX0s8NeEJgFur5NjFkR20Uys=; b=JSTw/RLwOAlKBB7e/25YzpmI2KMN8Kjr7Gh2YqR/gknmQ3550f1bFPZQ A4dy7OFGV2y1vb4Pp+V5OJvRANlN//tA3KAQRzTvrMCtgM7dcxN9gImYf w+hFYjZD6culaZaKztStW1zuOqaEdkJYXFKNFRtYji3qsJRYt2MWsgBkr kNGXuRPBjT4NehR0m9+Epnp6VgjuG9NCjLR9Ysg54rGly2+OspyM28soS uCyNiTdMigTLoi5BiPMgK6eInw4qlRpYs7AYzffvagQQZjRlk8TFhNPlM 8VK3cKtXviAUIeG7UqJXorG8eYoAE5Jo9jlmPCEi6yJSU8fNSzaL4ex9x g==; X-CSE-ConnectionGUID: mBOSxtqWTWuaUUdEkVV8yA== X-CSE-MsgGUID: 2xqiAxhFRqqhYsFcg/YEOA== X-IronPort-AV: E=McAfee;i="6800,10657,11737"; a="75282125" X-IronPort-AV: E=Sophos;i="6.23,137,1770624000"; d="scan'208";a="75282125" Received: from fmviesa004.fm.intel.com ([10.60.135.144]) by orvoesa110.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 23 Mar 2026 04:03:05 -0700 X-CSE-ConnectionGUID: 873TmT3jQ4y335vwFWd4BQ== X-CSE-MsgGUID: yWr1G0QiR3WIzW2GQd0Elg== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.23,137,1770624000"; d="scan'208";a="225713352" Received: from black.igk.intel.com ([10.91.253.5]) by fmviesa004.fm.intel.com with ESMTP; 23 Mar 2026 04:03:02 -0700 Received: by black.igk.intel.com (Postfix, from userid 1001) id 75D2995; Mon, 23 Mar 2026 12:03:01 +0100 (CET) Date: Mon, 23 Mar 2026 12:03:01 +0100 From: Mika Westerberg To: Lukas Wunner Cc: Bjorn Helgaas , Jonathan Corbet , linux-pci@vger.kernel.org, linux-doc@vger.kernel.org, Ilpo Jarvinen , Maciej Grochowski , Kai-Heng Feng Subject: Re: [PATCH] Documentation: PCI: Document decoding of TLP Header in AER messages Message-ID: <20260323110301.GX2275908@black.igk.intel.com> References: Precedence: bulk X-Mailing-List: linux-doc@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: On Mon, Mar 23, 2026 at 07:52:39AM +0100, Lukas Wunner wrote: > The prefix/header of the TLP that caused an error is recorded by the Root > Complex and emitted to the kernel log in raw hex format. Document the > existence and usage of tlp-tool, which allows decoding the TLP Header > into human-readable form. > > The TLP Header hints at the root cause of an error, yet is often ignored > because of its seeming opaqueness. Instead, PCIe errors are frequently > worked around by a change in the kernel without fully understanding the > actual source of the problem. With more documentation on available tools > we'll hopefully come up with better solutions. > > There are also wireshark dissectors for TLPs, but it seems they expect a > complete TLP, not just the header, and they cannot grok the hex format > emitted by the kernel directly. tlp-tool appears to be the most cut and > dried solution out there. > > Signed-off-by: Lukas Wunner > Cc: Maciej Grochowski Good idea, this is useful. Reviewed-by: Mika Westerberg