Messages in this thread Patch in this message | | | Subject | Re: [PATCH 1/1] iommu/vt-d: Fix dmar pte read access not set error | From | Lu Baolu <> | Date | Thu, 12 Dec 2019 09:00:18 +0800 |
| |
Hi,
On 12/12/19 12:35 AM, Jerry Snitselaar wrote: > On Wed Dec 11 19, Lu Baolu wrote: >> If the default DMA domain of a group doesn't fit a device, it >> will still sit in the group but use a private identity domain. >> When map/unmap/iova_to_phys come through iommu API, the driver >> should still serve them, otherwise, other devices in the same >> group will be impacted. Since identity domain has been mapped >> with the whole available memory space and RMRRs, we don't need >> to worry about the impact on it. >> > > Does this pose any potential issues with the reverse case where the > group has a default identity domain, and the first device fits that, > but a later device in the group needs dma and gets a private dma > domain?
No. iommu_map/unmap() should not be called for default identity domain.
if (unlikely(!(domain->type & __IOMMU_DOMAIN_PAGING))) return -EINVAL;
Best regards, baolu
> >> Link: https://www.spinics.net/lists/iommu/msg40416.html >> Cc: Jerry Snitselaar <jsnitsel@redhat.com> >> Reported-by: Jerry Snitselaar <jsnitsel@redhat.com> >> Fixes: 942067f1b6b97 ("iommu/vt-d: Identify default domains replaced >> with private") >> Cc: stable@vger.kernel.org # v5.3+ >> Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> >> --- >> drivers/iommu/intel-iommu.c | 8 -------- >> 1 file changed, 8 deletions(-) >> >> diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c >> index 0c8d81f56a30..b73bebea9148 100644 >> --- a/drivers/iommu/intel-iommu.c >> +++ b/drivers/iommu/intel-iommu.c >> @@ -5478,9 +5478,6 @@ static int intel_iommu_map(struct iommu_domain >> *domain, >> int prot = 0; >> int ret; >> >> - if (dmar_domain->flags & DOMAIN_FLAG_LOSE_CHILDREN) >> - return -EINVAL; >> - >> if (iommu_prot & IOMMU_READ) >> prot |= DMA_PTE_READ; >> if (iommu_prot & IOMMU_WRITE) >> @@ -5523,8 +5520,6 @@ static size_t intel_iommu_unmap(struct >> iommu_domain *domain, >> /* Cope with horrid API which requires us to unmap more than the >> size argument if it happens to be a large-page mapping. */ >> BUG_ON(!pfn_to_dma_pte(dmar_domain, iova >> VTD_PAGE_SHIFT, &level)); >> - if (dmar_domain->flags & DOMAIN_FLAG_LOSE_CHILDREN) >> - return 0; >> >> if (size < VTD_PAGE_SIZE << level_to_offset_bits(level)) >> size = VTD_PAGE_SIZE << level_to_offset_bits(level); >> @@ -5556,9 +5551,6 @@ static phys_addr_t >> intel_iommu_iova_to_phys(struct iommu_domain *domain, >> int level = 0; >> u64 phys = 0; >> >> - if (dmar_domain->flags & DOMAIN_FLAG_LOSE_CHILDREN) >> - return 0; >> - >> pte = pfn_to_dma_pte(dmar_domain, iova >> VTD_PAGE_SHIFT, &level); >> if (pte) >> phys = dma_pte_addr(pte); >> -- >> 2.17.1 >> >
| |