On 04/23/2018 04:30 PM, Logan Gunthorpe wrote:> > Signed-off-by: Logan Gunthorpe <logang@xxxxxxxxxxxx>> --- > drivers/pci/Kconfig | 9 +++++++++> drivers/pci/p2pdma.c | 45 ++++++++++++++++++++++++++++++---------------> drivers/pci/pci.c | 6 ++++++> include/linux/pci-p2pdma.h | 5 +++++> 4 files changed, 50 insertions(+), 15 deletions(-) > > diff --git a/drivers/pci/Kconfig b/drivers/pci/Kconfig > index b2396c22b53e..b6db41d4b708 100644 > --- a/drivers/pci/Kconfig > +++ b/drivers/pci/Kconfig > @@ -139,6 +139,15 @@ config PCI_P2PDMA > transations must be between devices behind the same root port. > (Typically behind a network of PCIe switches). > > + Enabling this option will also disable ACS on all ports behind > + any PCIe switch. This effectively puts all devices behind any > + switch heirarchy into the same IOMMU group. Which implies that hierarchy group, which and sames fixes in the commit description... > + individual devices behind any switch will not be able to be > + assigned to separate VMs because there is no isolation between > + them. Additionally, any malicious PCIe devices will be able to > + DMA to memory exposed by other EPs in the same domain as TLPs > + will not be checked by the IOMMU. > + > If unsure, say N. > > config PCI_LABEL -- ~Randy
