From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx0a-001b2d01.pphosted.com (mx0b-001b2d01.pphosted.com [148.163.158.5]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 3tSWDS4D8xzDwQ5 for ; Tue, 29 Nov 2016 15:44:40 +1100 (AEDT) Received: from pps.filterd (m0098417.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.17/8.16.0.17) with SMTP id uAT4i46i020759 for ; Mon, 28 Nov 2016 23:44:38 -0500 Received: from e23smtp01.au.ibm.com (e23smtp01.au.ibm.com [202.81.31.143]) by mx0a-001b2d01.pphosted.com with ESMTP id 270w68mp2k-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Mon, 28 Nov 2016 23:44:37 -0500 Received: from localhost by e23smtp01.au.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Tue, 29 Nov 2016 14:44:34 +1000 Received: from d23relay10.au.ibm.com (d23relay10.au.ibm.com [9.190.26.77]) by d23dlp03.au.ibm.com (Postfix) with ESMTP id 420683578058 for ; Tue, 29 Nov 2016 15:44:32 +1100 (EST) Received: from d23av05.au.ibm.com (d23av05.au.ibm.com [9.190.234.119]) by d23relay10.au.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id uAT4iWYr6029644 for ; Tue, 29 Nov 2016 15:44:32 +1100 Received: from d23av05.au.ibm.com (localhost [127.0.0.1]) by d23av05.au.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id uAT4iVgs003836 for ; Tue, 29 Nov 2016 15:44:32 +1100 Date: Tue, 29 Nov 2016 15:45:52 +1100 From: Gavin Shan To: Bjorn Helgaas Cc: Gavin Shan , clsoto@us.ibm.com, benh@kernel.crashing.org, linux-pci@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, mpe@ellerman.id.au Subject: Re: [PATCH v4 2/7] PCI: Ignore BAR updates on virtual functions Reply-To: Gavin Shan References: <20161129035218.21453.93986.stgit@bhelgaas-glaptop.roam.corp.google.com> <20161129041429.21453.83322.stgit@bhelgaas-glaptop.roam.corp.google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <20161129041429.21453.83322.stgit@bhelgaas-glaptop.roam.corp.google.com> Message-Id: <20161129044552.GA20642@gwshan> List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Mon, Nov 28, 2016 at 10:14:29PM -0600, Bjorn Helgaas wrote: >VF BARs are read-only zero, so updating VF BARs will not have any effect. >See the SR-IOV spec r1.1, sec 3.4.1.11. > >We already ignore these updates because of 70675e0b6a1a ("PCI: Don't try to >restore VF BARs"); this merely restructures it slightly to make it easier >to split updates for standard and SR-IOV BARs. > >Signed-off-by: Bjorn Helgaas >CC: Wei Yang Reviewed-by: Gavin Shan >--- > drivers/pci/pci.c | 4 ---- > drivers/pci/setup-res.c | 5 ++--- > 2 files changed, 2 insertions(+), 7 deletions(-) > >diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c >index ba34907..631eac2 100644 >--- a/drivers/pci/pci.c >+++ b/drivers/pci/pci.c >@@ -564,10 +564,6 @@ static void pci_restore_bars(struct pci_dev *dev) > { > int i; > >- /* Per SR-IOV spec 3.4.1.11, VF BARs are RO zero */ >- if (dev->is_virtfn) >- return; >- > for (i = 0; i < PCI_BRIDGE_RESOURCES; i++) > pci_update_resource(dev, i); > } >diff --git a/drivers/pci/setup-res.c b/drivers/pci/setup-res.c >index 66c4d8f..d2a32d8 100644 >--- a/drivers/pci/setup-res.c >+++ b/drivers/pci/setup-res.c >@@ -36,10 +36,9 @@ void pci_update_resource(struct pci_dev *dev, int resno) > enum pci_bar_type type; > struct resource *res = dev->resource + resno; > >- if (dev->is_virtfn) { >- dev_warn(&dev->dev, "can't update VF BAR%d\n", resno); >+ /* Per SR-IOV spec 3.4.1.11, VF BARs are RO zero */ >+ if (dev->is_virtfn) > return; >- } > > /* > * Ignore resources for unimplemented BARs and unused resource slots >