Hi Thomas, On 2020/11/13 3:15, Thomas Gleixner wrote:
The recent changes to store the MSI irqdomain pointer in struct device missed that Intel DMAR does not register virtual function devices. Due to that a VF device gets the plain PCI-MSI domain assigned and then issues compat MSI messages which get caught by the interrupt remapping unit. Cure that by inheriting the irq domain from the physical function device. That's a temporary workaround. The correct fix is to inherit the irq domain from the bus, but that's a larger effort which needs quite some other changes to the way how x86 manages PCI and MSI domains. Fixes: 85a8dfc57a0b ("iommm/vt-d: Store irq domain in struct device") Reported-by: Jason Gunthorpe <jgg@xxxxxxxxxx> Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx> --- drivers/iommu/intel/dmar.c | 19 ++++++++++++++++++- 1 file changed, 18 insertions(+), 1 deletion(-) --- a/drivers/iommu/intel/dmar.c +++ b/drivers/iommu/intel/dmar.c @@ -333,6 +333,11 @@ static void dmar_pci_bus_del_dev(struct dmar_iommu_notify_scope_dev(info); }+static inline void vf_inherit_msi_domain(struct pci_dev *pdev)+{ + dev_set_msi_domain(&pdev->dev, dev_get_msi_domain(&pdev->physfn->dev)); +} + static int dmar_pci_bus_notifier(struct notifier_block *nb, unsigned long action, void *data) { @@ -342,8 +347,20 @@ static int dmar_pci_bus_notifier(struct /* Only care about add/remove events for physical functions. * For VFs we actually do the lookup based on the corresponding * PF in device_to_iommu() anyway. */ - if (pdev->is_virtfn) + if (pdev->is_virtfn) { + /* + * Note: This is a horrible hack and needs to be cleaned + * up by assigning the domain to the bus, but that's too + * big of a change for post rc3. + * + * Ensure that the VF device inherits the irq domain of the + * PF device: + */ + if (action == BUS_NOTIFY_ADD_DEVICE) + vf_inherit_msi_domain(pdev); return NOTIFY_DONE; + } + if (action != BUS_NOTIFY_ADD_DEVICE && action != BUS_NOTIFY_REMOVED_DEVICE) return NOTIFY_DONE;
We also encountered this problem in internal testing. This patch can solve the problem. Acked-by: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx> Best regards, baolu
