Messages in this thread | | | Date | Tue, 30 Jun 2020 10:19:47 -0700 | From | Jacob Pan <> | Subject | Re: [PATCH 4/7] iommu/vt-d: Handle non-page aligned address |
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On Thu, 25 Jun 2020 18:05:52 +0800 Lu Baolu <baolu.lu@linux.intel.com> wrote:
> Hi, > > On 2020/6/23 23:43, Jacob Pan wrote: > > From: Liu Yi L <yi.l.liu@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. > > > > Signed-off-by: Liu Yi L <yi.l.liu@intel.com> > > Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com> > > --- > > drivers/iommu/intel/dmar.c | 19 +++++++++++++++++-- > > 1 file changed, 17 insertions(+), 2 deletions(-) > > > > diff --git a/drivers/iommu/intel/dmar.c b/drivers/iommu/intel/dmar.c > > index d9f973fa1190..53f4e5003620 100644 > > --- a/drivers/iommu/intel/dmar.c > > +++ b/drivers/iommu/intel/dmar.c > > @@ -1455,9 +1455,24 @@ 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); + > > + if (size_order) { > > + /* Take page address */ > > + desc.qw1 |= QI_DEV_EIOTLB_ADDR(addr); > > If size_order == 0 (that means only a single page is about to be > invalidated), do you still need to set ADDR field of the descriptor? > Good catch! we should always set addr. I will move addr assignment out of the if condition. . > Best regards, > baolu > > > + /* > > + * 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. > > + */ > > + desc.qw1 |= GENMASK_ULL(size_order + > > VTD_PAGE_SHIFT, > > + VTD_PAGE_SHIFT); > > + /* 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); > > } > >
[Jacob Pan]
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