On Thu, 2 Jul 2020 09:50:19 +0200 Auger Eric <eric.au...@redhat.com> wrote:
> Hi Jacob, > > On 7/1/20 5:33 PM, Jacob Pan wrote: > > From: Liu Yi L <yi.l....@intel.com> > > > > Address information for device TLB invalidation comes from userspace > > when device is directly assigned to a guest with vIOMMU support. > > VT-d requires page aligned address. This patch checks and enforce > > address to be page aligned, otherwise reserved bits can be set in > > the invalidation descriptor. Unrecoverable fault will be reported > > due to non-zero value in the reserved bits. > on the other hand if user space sends unaligned invalidations, > shouldn't it be reported in some way? > > > > Fixes: 61a06a16e36d8 ("iommu/vt-d: Support flushing more translation > > cache types") > > Acked-by: Lu Baolu <baolu...@linux.intel.com> > > Signed-off-by: Liu Yi L <yi.l....@intel.com> > > Signed-off-by: Jacob Pan <jacob.jun....@linux.intel.com> > > > > Signed-off-by: Jacob Pan <jacob.jun....@linux.intel.com> > > --- > > drivers/iommu/intel/dmar.c | 20 ++++++++++++++++++-- > > 1 file changed, 18 insertions(+), 2 deletions(-) > > > > diff --git a/drivers/iommu/intel/dmar.c b/drivers/iommu/intel/dmar.c > > index d9f973fa1190..3899f3161071 100644 > > --- a/drivers/iommu/intel/dmar.c > > +++ b/drivers/iommu/intel/dmar.c > > @@ -1455,9 +1455,25 @@ void qi_flush_dev_iotlb_pasid(struct > > intel_iommu *iommu, u16 sid, u16 pfsid, > > * Max Invs Pending (MIP) is set to 0 for now until we > > have DIT in > > * ECAP. > > */ > > - desc.qw1 |= addr & ~mask; > > - if (size_order) > > + if (addr & ~VTD_PAGE_MASK) > > + pr_warn_ratelimited("Invalidate non-page aligned > > address %llx\n", addr); + > > + /* Take page address */ > > + desc.qw1 |= QI_DEV_EIOTLB_ADDR(addr); > > + > > + if (size_order) { > > + /* > > + * Existing 0s in address below size_order may be > > the least > > + * significant bit, we must set them to 1s to > > avoid having > > + * smaller size than desired. > Shouldn't you test the input addr against the size_order. Aren't they > supposed to be consistent? Otherwise one should emit a warning at > least? Will check size_order and addr match to emit warning. Combine with VTD_PAGE_MASK check above. > > + */ > > + desc.qw1 |= GENMASK_ULL(size_order + > > VTD_PAGE_SHIFT, > > + VTD_PAGE_SHIFT); > nit: instead of working directly on .qw1, couldn't you perform all > those manipulations directly on addr? and eventually override qw1 at > the end? That is good too, I just felt it is more readable, which fields are being manipulated in qw1. > > + /* Clear size_order bit to indicate size */ > > + desc.qw1 &= ~mask; > > + /* Set the S bit to indicate flushing more than 1 > > page */ desc.qw1 |= QI_DEV_EIOTLB_SIZE; > > + } > > > > qi_submit_sync(iommu, &desc, 1, 0); > > } > > > Thanks > > Eric > [Jacob Pan] _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu