> -----邮件原件----- > 发件人: Jerry Snitselaar [mailto:jsnit...@redhat.com] > 发送时间: 2019年12月20日 17:23 > 收件人: Jim,Yan <jim...@baidu.com> > 抄送: j...@8bytes.org; iommu@lists.linux-foundation.org; > linux-ker...@vger.kernel.org > 主题: Re: [PATCH] iommu/vt-d: Don't reject nvme host due to scope mismatch > > On Fri Dec 20 19, jimyan wrote: > >On a system with an Intel PCIe port configured as a nvme host device, > >iommu initialization fails with > > > > DMAR: Device scope type does not match for 0000:80:00.0 > > > >This is because the DMAR table reports this device as having scope 2 > >(ACPI_DMAR_SCOPE_TYPE_BRIDGE): > > > > Isn't that a problem to be fixed in the DMAR table then? > > >but the device has a type 0 PCI header: > >80:00.0 Class 0600: Device 8086:2020 (rev 06) > >00: 86 80 20 20 47 05 10 00 06 00 00 06 10 00 00 00 > >10: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 > >20: 00 00 00 00 00 00 00 00 00 00 00 00 86 80 00 00 > >30: 00 00 00 00 90 00 00 00 00 00 00 00 00 01 00 00 > > > >VT-d works perfectly on this system, so there's no reason to bail out > >on initialization due to this apparent scope mismatch. Add the class > >0x600 ("PCI_CLASS_BRIDGE_HOST") as a heuristic for allowing DMAR > >initialization for non-bridge PCI devices listed with scope bridge. > > > >Signed-off-by: jimyan <jim...@baidu.com> > >--- > > drivers/iommu/dmar.c | 1 + > > 1 file changed, 1 insertion(+) > > > >diff --git a/drivers/iommu/dmar.c b/drivers/iommu/dmar.c index > >eecd6a421667..9faf2f0e0237 100644 > >--- a/drivers/iommu/dmar.c > >+++ b/drivers/iommu/dmar.c > >@@ -244,6 +244,7 @@ int dmar_insert_dev_scope(struct > dmar_pci_notify_info *info, > > info->dev->hdr_type != PCI_HEADER_TYPE_NORMAL) || > > (scope->entry_type == ACPI_DMAR_SCOPE_TYPE_BRIDGE && > > (info->dev->hdr_type == PCI_HEADER_TYPE_NORMAL && > >+ info->dev->class >> 8 != PCI_CLASS_BRIDGE_HOST && > > info->dev->class >> 8 != PCI_CLASS_BRIDGE_OTHER))) { > > pr_warn("Device scope type does not match for %s\n", > > pci_name(info->dev)); > >-- > >2.11.0 > > > >_______________________________________________ > >iommu mailing list > >iommu@lists.linux-foundation.org > >https://lists.linuxfoundation.org/mailman/listinfo/iommu > > Actually this patch is similar to the commit: ffb2d1eb88c3("iommu/vt-d: Don't reject NTB devices due to scope mismatch"). Besides, modifying DMAR table need OEM update BIOS. It is hard to implement.
Jim _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu
