On an AMD system, I/O page faults are usually logged like this:

        drvname 0000:05:00.0: Event logged [IO_PAGE_FAULT domain=0x0000 
address=0x0000000092050da0 flags=0x0020]

But sometimes they are logged like this instead, even for the exact
same PCI device:

        AMD-Vi: Event logged [IO_PAGE_FAULT device=05:00.0 domain=0x0000 
address=0x0000000092050de0 flags=0x0020]

This discrepancy appears to be caused by this code:

        if (dev_data && __ratelimit(&dev_data->rs)) {
                pci_err(pdev, "Event logged [IO_PAGE_FAULT domain=0x%04x 
address=0x%llx flags=0x%04x]\n",
                        domain_id, address, flags);
        } else if (printk_ratelimit()) {
                pr_err("Event logged [IO_PAGE_FAULT device=%02x:%02x.%x 
domain=0x%04x address=0x%llx flags=0x%04x]\n",
                        PCI_BUS_NUM(devid), PCI_SLOT(devid), PCI_FUNC(devid),
                        domain_id, address, flags);
        }

If an I/O page fault occurs for a PCI device with associated
iommu_dev_data, but for which the __ratelimit(&dev_data->rs) check fails,
we'll give it a second chance with printk_ratelimit(), and if that check
succeeds, we will log the fault anyway, but in a different format.

Change this to only check printk_ratelimit() if !dev_data, which seems to
be what had been originally intended.

Signed-off-by: Lennert Buytenhek <buyt...@wantstofly.org>
---
 drivers/iommu/amd/iommu.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/iommu/amd/iommu.c b/drivers/iommu/amd/iommu.c
index 811a49a95d04..7ae426b092f2 100644
--- a/drivers/iommu/amd/iommu.c
+++ b/drivers/iommu/amd/iommu.c
@@ -483,7 +483,7 @@ static void amd_iommu_report_page_fault(u16 devid, u16 
domain_id,
        if (dev_data && __ratelimit(&dev_data->rs)) {
                pci_err(pdev, "Event logged [IO_PAGE_FAULT domain=0x%04x 
address=0x%llx flags=0x%04x]\n",
                        domain_id, address, flags);
-       } else if (printk_ratelimit()) {
+       } else if (!dev_data && printk_ratelimit()) {
                pr_err("Event logged [IO_PAGE_FAULT device=%02x:%02x.%x 
domain=0x%04x address=0x%llx flags=0x%04x]\n",
                        PCI_BUS_NUM(devid), PCI_SLOT(devid), PCI_FUNC(devid),
                        domain_id, address, flags);
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