From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from e23smtp08.au.ibm.com ([202.81.31.141]:49831 "EHLO e23smtp08.au.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751211AbcA2KnU (ORCPT ); Fri, 29 Jan 2016 05:43:20 -0500 Received: from localhost by e23smtp08.au.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Fri, 29 Jan 2016 20:43:18 +1000 Subject: Re: [RFC PATCH v3 5/5] vfio-pci: Allow to mmap MSI-X table if host bridge supports filtering of MSIs To: Alex Williamson , kvm@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-doc@vger.kernel.org References: <1452841574-2781-1-git-send-email-xyjxie@linux.vnet.ibm.com> <1452841574-2781-6-git-send-email-xyjxie@linux.vnet.ibm.com> <1454021188.23148.7.camel@redhat.com> Cc: bhelgaas@google.com, corbet@lwn.net, aik@ozlabs.ru, 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 From: Yongji Xie Message-ID: <56AB421B.3070004@linux.vnet.ibm.com> Date: Fri, 29 Jan 2016 18:42:35 +0800 MIME-Version: 1.0 In-Reply-To: <1454021188.23148.7.camel@redhat.com> Content-Type: text/plain; charset=utf-8; format=flowed Sender: linux-pci-owner@vger.kernel.org List-ID: On 2016/1/29 6:46, Alex Williamson wrote: > On Fri, 2016-01-15 at 15:06 +0800, Yongji Xie wrote: >> Current vfio-pci implementation disallows to mmap MSI-X >> table in case that user get to touch this directly. >> >> But we should allow to mmap these MSI-X tables if the PCI >> host bridge supports filtering of MSIs. >> >> Signed-off-by: Yongji Xie >> --- >> drivers/vfio/pci/vfio_pci.c | 6 ++++-- >> 1 file changed, 4 insertions(+), 2 deletions(-) >> >> diff --git a/drivers/vfio/pci/vfio_pci.c b/drivers/vfio/pci/vfio_pci.c >> index 11fd0f0..4d68f6a 100644 >> --- a/drivers/vfio/pci/vfio_pci.c >> +++ b/drivers/vfio/pci/vfio_pci.c >> @@ -555,7 +555,8 @@ static long vfio_pci_ioctl(void *device_data, >> IORESOURCE_MEM && !pci_resources_share_page(pdev, >> info.index)) { >> info.flags |= VFIO_REGION_INFO_FLAG_MMAP; >> - if (info.index == vdev->msix_bar) { >> + if (!pci_host_bridge_msi_filtered_enabled(pdev) && >> + info.index == vdev->msix_bar) { >> ret = msix_sparse_mmap_cap(vdev, &caps); >> if (ret) >> return ret; >> @@ -967,7 +968,8 @@ static int vfio_pci_mmap(void *device_data, struct vm_area_struct *vma) >> if (phys_len < PAGE_SIZE || req_start + req_len > phys_len) >> return -EINVAL; >> >> - if (index == vdev->msix_bar) { >> + if (!pci_host_bridge_msi_filtered_enabled(pdev) && >> + index == vdev->msix_bar) { >> /* >> * Disallow mmaps overlapping the MSI-X table; users don't >> * get to touch this directly. We could find somewhere > What about read()/write() access, why would we allow mmap() but not > those? > Yes, you are right! I miss the MSI-X table check in vfio_pci_bar_rw(). I will fix it in next version. Thanks. Regards, Yongji Xie