From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Subject: Re: [PATCH 1/5] iov: Update virtfn_max_buses to validate offset and stride To: Bjorn Helgaas , Alexander Duyck References: <20151027204607.14626.59671.stgit@localhost.localdomain> <20151027205215.14626.93504.stgit@localhost.localdomain> <20151028163216.GA2927@localhost> Cc: bhelgaas@google.com, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org From: Alexander Duyck Message-ID: <56310C78.6030703@gmail.com> Date: Wed, 28 Oct 2015 10:57:12 -0700 MIME-Version: 1.0 In-Reply-To: <20151028163216.GA2927@localhost> Content-Type: text/plain; charset=windows-1252; format=flowed Sender: linux-kernel-owner@vger.kernel.org List-ID: On 10/28/2015 09:32 AM, Bjorn Helgaas wrote: > Hi Alex, > > Thanks a lot for cleaning this up. I think this is a great > improvement over what I did. > > On Tue, Oct 27, 2015 at 01:52:15PM -0700, Alexander Duyck wrote: >> This patch pulls the validation of offset and stride into virtfn_max_buses. >> The general idea is to validate offset and stride for each possible value >> of numvfs in addition to still determining the maximum bus value for the >> VFs. >> >> I also reversed the loop as the most likely maximum will be when numvfs is >> set to total_VFs. In addition this makes it so that we loop down to a >> value of 0 for numvfs which should be the resting state for the register. >> >> Fixes: 8e20e89658f2 ("PCI: Set SR-IOV NumVFs to zero after enumeration") >> Signed-off-by: Alexander Duyck > > I'd like to squash this together with my patch instead of having fixes > on top of fixes. What do you think of the following? (This applies > on top of 70675e0b6a1a ("PCI: Don't try to restore VF BARs")). > > > commit c20e11b572c5d4e4f01c86580a133122fbd13cfa > Author: Alexander Duyck > Date: Wed Oct 28 10:54:32 2015 -0500 > > PCI: Set SR-IOV NumVFs to zero after enumeration > > The enumeration path should leave NumVFs set to zero. But after > 4449f079722c ("PCI: Calculate maximum number of buses required for VFs"), > we call virtfn_max_buses() in the enumeration path, which changes NumVFs. > This NumVFs change is visible via lspci and sysfs until a driver enables > SR-IOV. > > Iterate from TotalVFs down to zero so NumVFs is zero when we're finished > computing the maximum number of buses. Validate offset and stride in > the loop, so we can test it at every possible NumVFs setting. Rename > virtfn_max_buses() to compute_max_vf_buses() to hint that it does have a > side effect of updating iov->max_VF_buses. > > [bhelgaas: changelog, rename, reverse sense of error path] > Fixes: 4449f079722c ("PCI: Calculate maximum number of buses required for VFs") > Based-on-patch-by: Ethan Zhao > Signed-off-by: Alexander Duyck > Signed-off-by: Bjorn Helgaas > This looks fine to me. Acked-by: Alexander Duyck