diff options
| author | Jean-Philippe Brucker <jean-philippe@linaro.org> | 2020-05-20 17:22:01 +0200 |
|---|---|---|
| committer | Joerg Roedel <jroedel@suse.de> | 2020-05-27 14:35:41 +0200 |
| commit | 7a441b2110527851f630144ec76ab8409e1d6c61 (patch) | |
| tree | 31988a75f053d89f24a343d2ca8925786e459ec4 /drivers | |
| parent | 521376741b2c26fe53a1ec24d02da24d477eb739 (diff) | |
| download | linux-7a441b2110527851f630144ec76ab8409e1d6c61.tar.bz2 | |
iommu/amd: Use pci_ats_supported()
The pci_ats_supported() function checks if a device supports ATS and is
allowed to use it. In addition to checking that the device has an ATS
capability and that the global pci=noats is not set
(pci_ats_disabled()), it also checks if a device is untrusted.
A device is untrusted if it is plugged into an external-facing port such
as Thunderbolt and could be spoofing an existing device to exploit
weaknesses in the IOMMU configuration. By calling pci_ats_supported() we
keep DTE[I]=0 for untrusted devices and abort transactions with
Pretranslated Addresses.
Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Reviewed-by: Joerg Roedel <jroedel@suse.de>
Link: https://lore.kernel.org/r/20200520152201.3309416-3-jean-philippe@linaro.org
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/iommu/amd_iommu.c | 12 |
1 files changed, 4 insertions, 8 deletions
diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c index 1880811cec33..254f028cd18e 100644 --- a/drivers/iommu/amd_iommu.c +++ b/drivers/iommu/amd_iommu.c @@ -291,16 +291,15 @@ static struct iommu_group *acpihid_device_group(struct device *dev) static bool pci_iommuv2_capable(struct pci_dev *pdev) { static const int caps[] = { - PCI_EXT_CAP_ID_ATS, PCI_EXT_CAP_ID_PRI, PCI_EXT_CAP_ID_PASID, }; int i, pos; - if (pci_ats_disabled()) + if (!pci_ats_supported(pdev)) return false; - for (i = 0; i < 3; ++i) { + for (i = 0; i < 2; ++i) { pos = pci_find_ext_capability(pdev, caps[i]); if (pos == 0) return false; @@ -3028,11 +3027,8 @@ int amd_iommu_device_info(struct pci_dev *pdev, memset(info, 0, sizeof(*info)); - if (!pci_ats_disabled()) { - pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_ATS); - if (pos) - info->flags |= AMD_IOMMU_DEVICE_FLAG_ATS_SUP; - } + if (pci_ats_supported(pdev)) + info->flags |= AMD_IOMMU_DEVICE_FLAG_ATS_SUP; pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_PRI); if (pos) |