From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.1 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id CB62BC46475 for ; Sat, 27 Oct 2018 07:34:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 90F4620868 for ; Sat, 27 Oct 2018 07:34:54 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="ikANX6k1" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 90F4620868 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-pci-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728257AbeJ0QO4 (ORCPT ); Sat, 27 Oct 2018 12:14:56 -0400 Received: from bombadil.infradead.org ([198.137.202.133]:48544 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727643AbeJ0QO4 (ORCPT ); Sat, 27 Oct 2018 12:14:56 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=In-Reply-To:Content-Type:MIME-Version :References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=kAR1ai/S1gEoexvLzEpemQBBndgOUaUOpPDik2CRLFw=; b=ikANX6k1GJaXTHUQ1U45DpvI1 WdOGM1JKTK6qtgypvXmqmJVqzcbVDMORTr3Upecmt05j0Gfp94PxW8IjzcqSd0EyPTgYBGDiI9MEa neWeD4v9UohwLJ1hwnC0bofTHDKlrvnnJvuXSCzKLAUpeqwuKfqHhK3KmC9cqrqAyLizmHeD8np1j pfMblUHpHENWu+cdAfinnBsp73nwjVlzBEJoZEQt9fndET08gKp9MQ4DrlRXTjqCUu+HX/tTwkw2k HUFWNbWF2RCuf2AOBqhsgfPvyduMt21Oyz5OrnF2E8E2WY97Myu0BMrjdeL1pFZ1wyoAcgGrjEWNI YTdOf/myg==; Received: from hch by bombadil.infradead.org with local (Exim 4.90_1 #2 (Red Hat Linux)) id 1gGJ7U-0007FK-FM; Sat, 27 Oct 2018 07:34:52 +0000 Date: Sat, 27 Oct 2018 00:34:52 -0700 From: Christoph Hellwig To: Jon Derrick Cc: linux-pci@vger.kernel.org, Bjorn Helgaas , Lorenzo Pieralisi , Keith Busch Subject: Re: [PATCH 3/3] PCI/VMD: Enable firmware-first combined model Message-ID: <20181027073452.GA15476@infradead.org> References: <1540585146-31876-1-git-send-email-jonathan.derrick@intel.com> <1540585146-31876-3-git-send-email-jonathan.derrick@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1540585146-31876-3-git-send-email-jonathan.derrick@intel.com> User-Agent: Mutt/1.9.2 (2017-12-15) X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org On Fri, Oct 26, 2018 at 02:19:06PM -0600, Jon Derrick wrote: > The VMD endpoint acts as a host bridge for a nested PCIe segment. This > segment and its ports and endpoints are not represented in ACPI tables > such as DSDT and HEST, so "firmware first" error handling is currently > unsupported in the driver in favor of OS native error handling. > > VMD does support firmware error handling where errors are signaled to > host firmware via SMI. VMD supports a "combined model" [1] where > OS-native error handling is used in addition to firmware. Because of > this combined model, this patch does not subscribe to the kernel > firmware-first architecture which would prevent OS native error > handling. This sounds really horrible. Why can't Intel just offer a tweak to disable this whole VMD nightmare and treat it like a normal PCIe bus, which would leave everyone much better off?