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=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS autolearn=unavailable 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 F1783C4151A for ; Thu, 31 Jan 2019 14:42:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id CF85120869 for ; Thu, 31 Jan 2019 14:42:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731608AbfAaOmn (ORCPT ); Thu, 31 Jan 2019 09:42:43 -0500 Received: from mx1.redhat.com ([209.132.183.28]:42926 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726820AbfAaOmn (ORCPT ); Thu, 31 Jan 2019 09:42:43 -0500 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 8ED49CAA8E; Thu, 31 Jan 2019 14:42:42 +0000 (UTC) Received: from redhat.com (ovpn-124-197.rdu2.redhat.com [10.10.124.197]) by smtp.corp.redhat.com (Postfix) with SMTP id AE07460BF7; Thu, 31 Jan 2019 14:42:40 +0000 (UTC) Date: Thu, 31 Jan 2019 09:42:40 -0500 From: "Michael S. Tsirkin" To: Bjorn Helgaas Cc: Stephen Rothwell , Linux Next Mailing List , Linux Kernel Mailing List , linux-pci@vger.kernel.org Subject: Re: linux-next: manual merge of the vhost tree with the pci tree Message-ID: <20190131094203-mutt-send-email-mst@kernel.org> References: <20190131134033.1ed0021d@canb.auug.org.au> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.38]); Thu, 31 Jan 2019 14:42:42 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Jan 31, 2019 at 08:15:50AM -0600, Bjorn Helgaas wrote: > On Wed, Jan 30, 2019 at 8:40 PM Stephen Rothwell wrote: > > > > Hi all, > > > > Today's linux-next merge of the vhost tree got a conflict in: > > > > drivers/pci/setup-bus.c > > > > between commit: > > > > 51c48b310183 ("PCI: Probe bridge window attributes once at enumeration-time") > > > > from the pci tree and commit: > > > > 955156f34e7d ("PCI: avoid bridge feature re-probing on hotplug") > > > > from the vhost tree. > > > > I fixed it up (hopefully - see below) and can carry the fix as > > necessary. This is now fixed as far as linux-next is concerned, but any > > non trivial conflicts should be mentioned to your upstream maintainer > > when your tree is submitted for merging. You may also want to consider > > cooperating with the maintainer of the conflicting tree to minimise any > > particularly complex conflicts. > > 51c48b310183 and 955156f34e7d are both to solve the same problem, so I > think the best resolution is to drop 955156f34e7d from the vhost tree > completely. Will do. > The remaining wrinkle to work out is that we need a stable backport. > 51c48b310183 is technically a little large for a stable backport, so I > want to have a solid justification for it. As soon as I get a > kernel.org bugzilla with those details (who's affected by the > breakage, what the failure looks like, how to reproduce it, etc), I'll > add that URL and the stable tag. > > Bjorn OK. > > diff --cc drivers/pci/setup-bus.c > > index 1941bb0a6c13,d5c25d465d97..000000000000 > > --- a/drivers/pci/setup-bus.c > > +++ b/drivers/pci/setup-bus.c > > @@@ -735,17 -735,50 +735,26 @@@ int pci_claim_bridge_resource(struct pc > > base/limit registers must be read-only and read as 0. */ > > static void pci_bridge_check_ranges(struct pci_bus *bus) > > { > > - u16 io; > > - u32 pmem; > > struct pci_dev *bridge = bus->self; > > - struct resource *b_res; > > - > > - b_res = &bridge->resource[PCI_BRIDGE_RESOURCES]; > > + struct resource *b_res = &bridge->resource[PCI_BRIDGE_RESOURCES]; > > > > + /* > > + * Don't re-check after this was called once already: > > + * important since bridge might be in use. > > + * Note: this is only reliable because as per spec all PCI to PCI > > + * bridges support memory unconditionally so IORESOURCE_MEM is set. > > + */ > > + if (b_res[1].flags & IORESOURCE_MEM) > > + return; > > + > > b_res[1].flags |= IORESOURCE_MEM; > > > > - pci_read_config_word(bridge, PCI_IO_BASE, &io); > > - if (!io) { > > - pci_write_config_word(bridge, PCI_IO_BASE, 0xe0f0); > > - pci_read_config_word(bridge, PCI_IO_BASE, &io); > > - pci_write_config_word(bridge, PCI_IO_BASE, 0x0); > > - } > > - if (io) > > + if (bridge->io_window) > > b_res[0].flags |= IORESOURCE_IO; > > > > - /* DECchip 21050 pass 2 errata: the bridge may miss an address > > - disconnect boundary by one PCI data phase. > > - Workaround: do not use prefetching on this device. */ > > - if (bridge->vendor == PCI_VENDOR_ID_DEC && bridge->device == 0x0001) > > - return; > > - > > - pci_read_config_dword(bridge, PCI_PREF_MEMORY_BASE, &pmem); > > - if (!pmem) { > > - pci_write_config_dword(bridge, PCI_PREF_MEMORY_BASE, > > - 0xffe0fff0); > > - pci_read_config_dword(bridge, PCI_PREF_MEMORY_BASE, &pmem); > > - pci_write_config_dword(bridge, PCI_PREF_MEMORY_BASE, 0x0); > > - } > > - if (pmem) { > > + if (bridge->pref_window) { > > b_res[2].flags |= IORESOURCE_MEM | IORESOURCE_PREFETCH; > > - if ((pmem & PCI_PREF_RANGE_TYPE_MASK) == > > - PCI_PREF_RANGE_TYPE_64) { > > + if (bridge->pref_64_window) { > > b_res[2].flags |= IORESOURCE_MEM_64; > > b_res[2].flags |= PCI_PREF_RANGE_TYPE_64; > > }