@@ -51,6 +51,7 @@
#define CONTEXT_SIZE VTD_PAGE_SIZE
#define IS_GFX_DEVICE(pdev) ((pdev->class >> 16) == PCI_BASE_CLASS_DISPLAY)
+#define IS_USB_DEVICE(pdev) ((pdev->class >> 8) == PCI_CLASS_SERIAL_USB)
#define IS_ISA_DEVICE(pdev) ((pdev->class >> 8) == PCI_CLASS_BRIDGE_ISA)
#define IS_AZALIA(pdev) ((pdev)->vendor == 0x8086 && (pdev)->device == 0x3a3e)
@@ -2538,6 +2539,10 @@ static bool device_has_rmrr(struct device *dev)
* In both cases we assume that PCI USB devices with RMRRs have them largely
* for historical reasons and that the RMRR space is not actively used post
* boot. This exclusion may change if vendors begin to abuse it.
+ *
+ * The same exception is made for graphics devices, with the requirement that
+ * any use of the RMRR regions will be torn down before assigning the device
+ * to a guest.
*/
static bool device_is_rmrr_locked(struct device *dev)
{
@@ -2547,7 +2552,7 @@ static bool device_is_rmrr_locked(struct device *dev)
if (dev_is_pci(dev)) {
struct pci_dev *pdev = to_pci_dev(dev);
- if ((pdev->class >> 8) == PCI_CLASS_SERIAL_USB)
+ if (IS_USB_DEVICE(pdev) || IS_GFX_DEVICE(pdev))
return false;
}
This is a note to let you know that I have just added a patch titled iommu/vt-d: Allow RMRR on graphics devices too to the linux-3.16.y-queue branch of the 3.16.y-ckt extended stable tree which can be found at: http://kernel.ubuntu.com/git/ubuntu/linux.git/log/?h=linux-3.16.y-queue This patch is scheduled to be released in version 3.16.7-ckt14. If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.16.y-ckt tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Luis ------ From d99c5bd41caa3c23391f956a5b7b7d47d1fd4f6a Mon Sep 17 00:00:00 2001 From: David Woodhouse <David.Woodhouse@intel.com> Date: Wed, 25 Mar 2015 15:05:47 +0000 Subject: iommu/vt-d: Allow RMRR on graphics devices too commit 18436afdc11a00ac881990b454cfb2eae81d6003 upstream. Commit c875d2c1 ("iommu/vt-d: Exclude devices using RMRRs from IOMMU API domains") prevents certain options for devices with RMRRs. This even prevents those devices from getting a 1:1 mapping with 'iommu=pt', because we don't have the code to handle *preserving* the RMRR regions when moving the device between domains. There's already an exclusion for USB devices, because we know the only reason for RMRRs there is a misguided desire to keep legacy keyboard/mouse emulation running in some theoretical OS which doesn't have support for USB in its own right... but which *does* enable the IOMMU. Add an exclusion for graphics devices too, so that 'iommu=pt' works there. We should be able to successfully assign graphics devices to guests too, as long as the initial handling of stolen memory is reconfigured appropriately. This has certainly worked in the past. Signed-off-by: David Woodhouse <David.Woodhouse@intel.com> Signed-off-by: Luis Henriques <luis.henriques@canonical.com> --- drivers/iommu/intel-iommu.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-)