2 files changed, 27 insertions, 0 deletions

diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c
index 9fab30af0e75..084587d7cd13 100644
--- a/drivers/pci/msi.c
+++ b/drivers/pci/msi.c
@@ -590,6 +590,20 @@ static struct msi_desc *msi_setup_entry(struct pci_dev *dev)
         return entry;
 }
 
+static int msi_verify_entries(struct pci_dev *dev)
+{
+        struct msi_desc *entry;
+
+        list_for_each_entry(entry, &dev->msi_list, list) {
+                if (!dev->no_64bit_msi || !entry->msg.address_hi)
+                        continue;
+                dev_err(&dev->dev, "Device has broken 64-bit MSI but arch"
+                        " tried to assign one above 4G\n");
+                return -EIO;
+        }
+        return 0;
+}
+
 /**
  * msi_capability_init - configure device's MSI capability structure
  * @dev: pointer to the pci_dev data structure of MSI device function
@@ -627,6 +641,13 @@ static int msi_capability_init(struct pci_dev *dev, int nvec)
                 return ret;
         }
 
+        ret = msi_verify_entries(dev);
+        if (ret) {
+                msi_mask_irq(entry, mask, ~mask);
+                free_msi_irqs(dev);
+                return ret;
+        }
+
         ret = populate_msi_sysfs(dev);
         if (ret) {
                 msi_mask_irq(entry, mask, ~mask);
@@ -739,6 +760,11 @@ static int msix_capability_init(struct pci_dev *dev,
         if (ret)
                 goto out_avail;
 
+        /* Check if all MSI entries honor device restrictions */
+        ret = msi_verify_entries(dev);
+        if (ret)
+                goto out_free;
+
         /*
          * Some devices require MSI-X to be enabled before we can touch the
          * MSI-X registers.  We need to mask all the vectors to prevent
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 5be8db45e368..4c8ac5fcc224 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -331,6 +331,7 @@ struct pci_dev {
         unsigned int    is_added:1;
         unsigned int    is_busmaster:1; /* device is busmaster */
         unsigned int    no_msi:1;       /* device may not use msi */
+        unsigned int    no_64bit_msi:1; /* device may only use 32-bit MSIs */
         unsigned int    block_cfg_access:1;     /* config space access is blocked */
         unsigned int    broken_parity_status:1; /* Device generates false positive parity */
         unsigned int    irq_reroute_variant:2;  /* device needs IRQ rerouting variant */