From: Prarit Bhargava <prarit@redhat.com>
Date: Tue, 2 Feb 2010 15:06:47 -0500
Subject: [pci] aer: disable advanced error reporting by default
Message-id: <4B683F87.4090805@redhat.com>
Patchwork-id: 23100
O-Subject: Re: [RHEL5] PCI AER: disable aer by default
Bugzilla: 559978
RH-Acked-by: Dean Nelson <dnelson@redhat.com>
RH-Acked-by: Andy Gospodarek <gospo@redhat.com>

Gary Case noticed this obvious flaw in the PCI AER functionality.  If PCI AER
registers the ACPI _OSC method early in the boot process, PCI AER takes control
of the PCIE hotplug functionality.

This then limits the hotplug operations to the pciehp driver, effectively
disabling the apciphp driver.

By default PCI AER must be disabled in RHEL5 (and only RHEL5) in order to
maintain backward compatibility of the acpiphp driver for our customers, some
of which use the acpiphp sysfs files in applications.

Successfully tested by me.

Resolves BZ 559978.

Signed-off-by: Jarod Wilson <jarod@redhat.com>

diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 5887dd0..e91fbcf 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -1331,9 +1331,9 @@ running once the system is up.
 				Mechanism 1.
 		conf2		[IA-32] Force use of PCI Configuration
 				Mechanism 2.
-		noaer           [PCIE] If the PCIEAER kernel config parameter is
-				enabled, this kernel boot option can be used to
-				disable the use of PCIE advanced error reporting.
+		aer		[PCIE] By default in RHEL5, PCIEAER is disabled.
+				This kernel boot option can be used to enable
+				the use of the PCIE advanced error reporting.
 		nommconf	[IA-32,X86_64] Disable use of MMCONFIG for PCI
 				Configuration
 		nomsi		[MSI] If the PCI_MSI kernel config parameter is
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 6ec14fc..cf4f719 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -1832,8 +1832,8 @@ static int __devinit pci_setup(char *str)
 		if (*str && (str = pcibios_setup(str)) && *str) {
 			if (!strcmp(str, "nomsi")) {
 				pci_no_msi();
-			} else if (!strcmp(str, "noaer")) {
-				pci_no_aer();
+			} else if (!strcmp(str, "aer")) {
+				pci_aer_enable();
 			} else {
 				printk(KERN_ERR "PCI: Unknown option `%s'\n",
 						str);
diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
index 0bf784e..dbf7048 100644
--- a/drivers/pci/pci.h
+++ b/drivers/pci/pci.h
@@ -60,9 +60,9 @@ static inline void pci_restore_msix_state(struct pci_dev *dev) {}
 #endif
 
 #ifdef CONFIG_PCIEAER
-void pci_no_aer(void);
+void pci_aer_enable(void);
 #else
-static inline void pci_no_aer(void) { }
+static inline void pci_aer_enable(void) { }
 #endif
 
 static inline int pci_no_d1d2(struct pci_dev *dev)
diff --git a/drivers/pci/pcie/aer/aerdrv.c b/drivers/pci/pcie/aer/aerdrv.c
index a6fec8a..2bbbfb6 100644
--- a/drivers/pci/pcie/aer/aerdrv.c
+++ b/drivers/pci/pcie/aer/aerdrv.c
@@ -72,11 +72,11 @@ static struct pcie_port_service_driver aerdriver = {
 	.reset_link	= aer_root_reset,
 };
 
-static int pcie_aer_disable;
+static int pcie_aer_disable = 1;
 
-void pci_no_aer(void)
+void pci_aer_enable(void)
 {
-	pcie_aer_disable = 1;	/* has priority over 'forceload' */
+	pcie_aer_disable = 0;	/* has priority over 'forceload' */
 }
 
 /**