From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from e23smtp07.au.ibm.com (e23smtp07.au.ibm.com [202.81.31.140]) (using TLSv1.2 with cipher CAMELLIA256-SHA (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 3qfnPH4sJ4zDq6B for ; Wed, 6 Apr 2016 10:57:07 +1000 (AEST) Received: from localhost by e23smtp07.au.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Wed, 6 Apr 2016 10:57:05 +1000 Received: from d23relay10.au.ibm.com (d23relay10.au.ibm.com [9.190.26.77]) by d23dlp02.au.ibm.com (Postfix) with ESMTP id 4DC192BB0054 for ; Wed, 6 Apr 2016 10:57:02 +1000 (EST) Received: from d23av04.au.ibm.com (d23av04.au.ibm.com [9.190.235.139]) by d23relay10.au.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id u360usI36750712 for ; Wed, 6 Apr 2016 10:57:02 +1000 Received: from d23av04.au.ibm.com (localhost [127.0.0.1]) by d23av04.au.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id u360uT7T031310 for ; Wed, 6 Apr 2016 10:56:29 +1000 Date: Wed, 6 Apr 2016 10:55:34 +1000 From: Gavin Shan To: Yongji Xie Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-doc@vger.kernel.org, bhelgaas@google.com, corbet@lwn.net, aik@ozlabs.ru, alex.williamson@redhat.com, benh@kernel.crashing.org, paulus@samba.org, mpe@ellerman.id.au, warrier@linux.vnet.ibm.com, zhong@linux.vnet.ibm.com, nikunj@linux.vnet.ibm.com, gwshan@linux.vnet.ibm.com Subject: Re: [RFC v5 2/7] PCI: Do not Use IORESOURCE_STARTALIGN to identify bridge resources Message-ID: <20160406005534.GB6187@gwshan> Reply-To: Gavin Shan References: <1459863813-2830-1-git-send-email-xyjxie@linux.vnet.ibm.com> <1459863813-2830-3-git-send-email-xyjxie@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <1459863813-2830-3-git-send-email-xyjxie@linux.vnet.ibm.com> List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Tue, Apr 05, 2016 at 09:43:30PM +0800, Yongji Xie wrote: >Now we use the IORESOURCE_STARTALIGN to identify >bridge resources in __assign_resources_sorted(). >That's quite fragile. We can't make sure that >the PCI devices' resources will not use >IORESOURCE_STARTALIGN any more. > >In this patch, we try to use a more robust way >to identify bridge resources. > >Signed-off-by: Yongji Xie >--- > drivers/pci/setup-bus.c | 10 +++++++--- > 1 file changed, 7 insertions(+), 3 deletions(-) > >diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c >index 7796d0a..bffcf1e 100644 >--- a/drivers/pci/setup-bus.c >+++ b/drivers/pci/setup-bus.c >@@ -391,6 +391,7 @@ static void __assign_resources_sorted(struct list_head *head, > struct pci_dev_resource *dev_res, *tmp_res, *dev_res2; > unsigned long fail_type; > resource_size_t add_align, align; >+ int index; > > /* Check if optional add_size is there */ > if (!realloc_head || list_empty(realloc_head)) >@@ -411,11 +412,14 @@ static void __assign_resources_sorted(struct list_head *head, > > /* > * There are two kinds of additional resources in the list: >- * 1. bridge resource -- IORESOURCE_STARTALIGN >- * 2. SR-IOV resource -- IORESOURCE_SIZEALIGN >+ * 1. bridge resource >+ * 2. SR-IOV resource > * Here just fix the additional alignment for bridge > */ >- if (!(dev_res->res->flags & IORESOURCE_STARTALIGN)) >+ index = dev_res->res - dev_res->dev->resource; >+ if (pci_is_bridge(dev_res->dev) && >+ index >= PCI_BRIDGE_RESOURCES && >+ index <= PCI_BRIDGE_RESOURCE_END) > continue; Yongji, the condition seems incorrect. According to the comments in the code, it's resizing bridge's windows. So I think the code would be something like below? if (!pci_is_bridge(dev_res->dev) || index < PCI_BRIDGE_RESOURCES || index > PCI_BRIDGE_RESOURCE_END) continue; > > add_align = get_res_add_align(realloc_head, dev_res->res); Thanks, Gavin