[PATCH 2/2] PCI/EDR: Defer AER status clearing until after recovery

[Danielle Costantino <dcostantino@meta.com>]

edr_handle_event() calls pci_aer_raw_clear_status() immediately after
dpc_process_error() but before pcie_do_recovery().  While
dpc_process_error() has already read and logged the AER uncorrectable
status by this point, clearing the registers before recovery means
that driver error_detected/slot_reset/resume callbacks invoked by
pcie_do_recovery() can no longer inspect the AER status to make their
own decisions.

Additionally, in the firmware-first EDR path, the normal AER clearing
inside pcie_do_recovery() is a no-op because pcie_aer_is_native()
returns false, so pci_aer_raw_clear_status() in edr_handle_event() is
the only place these registers get cleared.  Moving it after recovery
completes keeps the diagnostic data available throughout the entire
recovery sequence.

Move pci_aer_raw_clear_status() to after pcie_do_recovery() returns so
AER registers remain readable during the full recovery sequence.

Fixes: ac1c8e35a326 ("PCI/DPC: Add Error Disconnect Recover (EDR) support")
Signed-off-by: Danielle Costantino <dcostantino@meta.com>
---
 drivers/pci/pcie/edr.c | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/drivers/pci/pcie/edr.c b/drivers/pci/pcie/edr.c
index e86298dbbcff..94a0e5e58fea 100644
--- a/drivers/pci/pcie/edr.c
+++ b/drivers/pci/pcie/edr.c
@@ -191,7 +191,6 @@ static void edr_handle_event(acpi_handle handle, u32 event, void *data)
 	}
 
 	dpc_process_error(edev);
-	pci_aer_raw_clear_status(edev);
 
 	/*
 	 * Irrespective of whether the DPC event is triggered by ERR_FATAL
@@ -200,6 +199,16 @@ static void edr_handle_event(acpi_handle handle, u32 event, void *data)
 	 */
 	estate = pcie_do_recovery(edev, pci_channel_io_frozen, dpc_reset_link);
 
+	/*
+	 * Clear AER status only after pcie_do_recovery() completes.
+	 * dpc_process_error() has already read and logged the AER
+	 * status above.  Deferring the clear keeps diagnostic data
+	 * available to driver callbacks invoked during recovery and
+	 * avoids interfering with any AER status reads they may
+	 * perform.
+	 */
+	pci_aer_raw_clear_status(edev);
+
 send_ost:
 
 	/*
-- 
2.47.3