Re: [PATCH v6 03/16] PCI/AER: Consolidate Error Source ID logging in aer_print_port_info()

On Mon, May 19, 2025 at 04:39:19PM -0700, Sathyanarayanan Kuppuswamy wrote:

On 5/19/25 2:35 PM, Bjorn Helgaas wrote:

quoted

From: Bjorn Helgaas <bhelgaas@google.com>

Previously we decoded the AER Error Source ID in two places.  Consolidate
them so both places use aer_print_port_info().  Add a "details" parameter
so we can add a note when we didn't find any downstream devices with errors
logged in their AER Capability.

When we didn't read any error details from the source device, we logged two
messages: one in aer_isr_one_error() and another in find_source_device().
Since they both contain the same information, only log the first one when
when find_source_device() has found error details.

/s/when//

Fixed, thanks!

quoted

-	pci_info(dev, "%s%s error message received from %04x:%02x:%02x.%d\n",
+	pci_info(dev, "%s%s error message received from %04x:%02x:%02x.%d%s\n",

Instead of relying on the callers, why not add a space before details here?

Could, but I don't like adding an extra space at the end of the line
when the caller passes "".  The extra space could make the line wrap
unnecessarily.

quoted

  		 info->multi_error_valid ? "Multiple " : "",
  		 aer_error_severity_string[info->severity],
  		 pci_domain_nr(dev->bus), bus, PCI_SLOT(devfn),
-		 PCI_FUNC(devfn));
+		 PCI_FUNC(devfn), details);
  }
  #ifdef CONFIG_ACPI_APEI_PCIEAER

@@ -926,13 +927,13 @@ static bool find_source_device(struct pci_dev *parent,
  	else
  		pci_walk_bus(parent->subordinate, find_device_iter, e_info);
+	/*
+	 * If we didn't find any devices with errors logged in the AER
+	 * Capability, just print the Error Source ID from the Root Port or
+	 * RCEC that received an ERR_* Message.
+	 */
  	if (!e_info->error_dev_num) {
-		u8 bus = e_info->id >> 8;
-		u8 devfn = e_info->id & 0xff;
-
-		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));
+		aer_print_port_info(parent, e_info, " (no details found)");
  		return false;
  	}
  	return true;

@@ -1297,10 +1298,11 @@ static void aer_isr_one_error(struct aer_rpc *rpc,
  			e_info.multi_error_valid = 1;
  		else
  			e_info.multi_error_valid = 0;
-		aer_print_port_info(pdev, &e_info);

Instead of printing the error information in find_source_device() (a helper function), I think it be better to print it here (the error handler). source_found = find_source_device(pdev, &e_info); aer_print_port_info(pdev, &e_info, source_found? "" : "(no details found) " );

if (source_found) aer_process_err_devices(&e_info)

Great idea, thanks!  That looks much nicer.

quoted

-		if (find_source_device(pdev, &e_info))
+		if (find_source_device(pdev, &e_info)) {
+			aer_print_port_info(pdev, &e_info, "");
  			aer_process_err_devices(&e_info);
+		}
  	}
  	if (e_src->status & PCI_ERR_ROOT_UNCOR_RCV) {

@@ -1316,10 +1318,10 @@ static void aer_isr_one_error(struct aer_rpc *rpc,
  		else
  			e_info.multi_error_valid = 0;
-		aer_print_port_info(pdev, &e_info);
-
-		if (find_source_device(pdev, &e_info))
+		if (find_source_device(pdev, &e_info)) {
+			aer_print_port_info(pdev, &e_info, "");
  			aer_process_err_devices(&e_info);
+		}
  	}
  }

-- 
Sathyanarayanan Kuppuswamy
Linux Kernel Developer