Re: [PATCH] iommu/vt-d: Allocate reserved region for ISA with correct permission

[Lu Baolu <baolu.lu@linux.intel.com>]

Hi Jerry,

On 12/13/19 1:36 PM, Jerry Snitselaar wrote:
> Currently the reserved region for ISA is allocated with no
> permissions. If a dma domain is being used, mapping this region will
> fail. Set the permissions to DMA_PTE_READ|DMA_PTE_WRITE.
> 
> Cc: Joerg Roedel <jroedel@suse.de>
> Cc: Lu Baolu <baolu.lu@linux.intel.com>
> Cc: iommu@lists.linux-foundation.org
> Cc: stable@vger.kernel.org # v5.3+
> Fixes: d850c2ee5fe2 ("iommu/vt-d: Expose ISA direct mapping region via iommu_get_resv_regions")
> Signed-off-by: Jerry Snitselaar <jsnitsel@redhat.com>
> ---
>   drivers/iommu/intel-iommu.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c
> index 0c8d81f56a30..998529cebcf2 100644
> --- a/drivers/iommu/intel-iommu.c
> +++ b/drivers/iommu/intel-iommu.c
> @@ -5736,7 +5736,7 @@ static void intel_iommu_get_resv_regions(struct device *device,
>   		struct pci_dev *pdev = to_pci_dev(device);
>   
>   		if ((pdev->class >> 8) == PCI_CLASS_BRIDGE_ISA) {
> -			reg = iommu_alloc_resv_region(0, 1UL << 24, 0,
> +			reg = iommu_alloc_resv_region(0, 1UL << 24, prot,
>   						      IOMMU_RESV_DIRECT);


This also applies to the IOAPIC range. Can you please change them
together?

diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c
index 0c8d81f56a30..256e48434f68 100644
--- a/drivers/iommu/intel-iommu.c
+++ b/drivers/iommu/intel-iommu.c
@@ -5736,7 +5736,7 @@ static void intel_iommu_get_resv_regions(struct 
device *device,
                 struct pci_dev *pdev = to_pci_dev(device);

                 if ((pdev->class >> 8) == PCI_CLASS_BRIDGE_ISA) {
-                       reg = iommu_alloc_resv_region(0, 1UL << 24, 0,
+                       reg = iommu_alloc_resv_region(0, 1UL << 24, prot,
                                                       IOMMU_RESV_DIRECT);
                         if (reg)
                                 list_add_tail(&reg->list, head);
@@ -5746,7 +5746,7 @@ static void intel_iommu_get_resv_regions(struct 
device *device,

         reg = iommu_alloc_resv_region(IOAPIC_RANGE_START,
                                       IOAPIC_RANGE_END - 
IOAPIC_RANGE_START + 1,
-                                     0, IOMMU_RESV_MSI);
+                                     prot, IOMMU_RESV_MSI);
         if (!reg)
                 return;
         list_add_tail(&reg->list, head);

Best regards,
baolu

>   			if (reg)
>   				list_add_tail(&reg->list, head);
>