On Tue, Jan 02, 2024 at 11:22:53AM -0800, Kuppuswamy Sathyanarayanan wrote:

On 12/6/2023 2:42 PM, Bjorn Helgaas wrote:

quoted

From: Bjorn Helgaas <bhelgaas@google.com>

When a device with AER detects an error, it logs error information in its
own AER Error Status registers.  It may send an Error Message to the Root
Port (RCEC in the case of an RCiEP), which logs the fact that an Error
Message was received (Root Error Status) and the Requester ID of the
message source (Error Source Identification).

aer_print_port_info() prints the Requester ID from the Root Port Error
Source in the usual Linux "bb:dd.f" format, but when find_source_device()
finds no error details in the hierarchy below the Root Port, it printed the
raw Requester ID without decoding it.

Decode the Requester ID in the usual Linux format so it matches other
messages.

Sample message changes:

  - pcieport 0000:00:1c.5: AER: Correctable error received: 0000:00:1c.5
  - pcieport 0000:00:1c.5: AER: can't find device of ID00e5
  + pcieport 0000:00:1c.5: AER: Correctable error message received from 0000:00:1c.5
  + pcieport 0000:00:1c.5: AER: found no error details for 0000:00:1c.5

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

Except for the suggestion given below, it looks good to me.

Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>

Thanks for taking a look!

quoted

@@ -740,7 +740,7 @@ static void aer_print_port_info(struct pci_dev *dev, struct aer_err_info *info)
 	u8 bus = info->id >> 8;
 	u8 devfn = info->id & 0xff;
 
-	pci_info(dev, "%s%s error received: %04x:%02x:%02x.%d\n",
+	pci_info(dev, "%s%s error message received from %04x:%02x:%02x.%d\n",
 		 info->multi_error_valid ? "Multiple " : "",
 		 aer_error_severity_string[info->severity],
 		 pci_domain_nr(dev->bus), bus, PCI_SLOT(devfn),

@@ -929,7 +929,12 @@ static bool find_source_device(struct pci_dev *parent,
 		pci_walk_bus(parent->subordinate, find_device_iter, e_info);
 
 	if (!e_info->error_dev_num) {
-		pci_info(parent, "can't find device of ID%04x\n", e_info->id);
+		u8 bus = e_info->id >> 8;
+		u8 devfn = e_info->id & 0xff;

You can use PCI_BUS_NUM(e_info->id) for getting bus number.  Since
you are extracting this info in more than one place, maybe you can
also define a macro PCI_DEVFN(id) (following PCI_BUS_NUM()).

Thanks, both good ideas.

We already have a PCI_DEVFN() that *combines* slot + func into devfn,
so we'd have to come up with a different name.

I'll add a patch to use PCI_BUS_NUM() in the two places here and in
pme.c.

I think I'll wait with these until after the v6.7 release.

quoted

+		pci_info(parent, "found no error details for %04x:%02x:%02x.%d\n",
+			 pci_domain_nr(parent->bus), bus, PCI_SLOT(devfn),
+			 PCI_FUNC(devfn));
 		return false;
 	}
 	return true;

-- 
Sathyanarayanan Kuppuswamy
Linux Kernel Developer