From: Prarit Bhargava <prarit@redhat.com>
Date: Wed, 16 Dec 2009 18:42:21 -0500
Subject: : PCI AER HEST Disable Support
Message-id: <20091216183822.16974.89492.sendpatchset@prarit.bos.redhat.com>
Patchwork-id: 22005
O-Subject: [RHEL5 2/2]: PCI AER HEST Disable Support
Bugzilla: 547762

commit f23c689ef61083774cefedb4445130bf0de459e7
Author: Prarit Bhargava <prarit@redhat.com>
Date:   Wed Dec 16 13:12:56 2009 -0500

    PCI AER HEST Disable Support

    Add an boot option to disable ACPI HEST.

    Successfully tested by me:

    With HEST on,

    aer 0000:00:01.0:pcie01: PCIe errors handled by platform firmware.
    aer 0000:00:02.0:pcie01: PCIe errors handled by platform firmware.
    aer 0000:00:03.0:pcie01: PCIe errors handled by platform firmware.
    aer 0000:00:05.0:pcie01: PCIe errors handled by platform firmware.
    aer 0000:00:07.0:pcie01: PCIe errors handled by platform firmware.
    aer 0000:00:09.0:pcie01: PCIe errors handled by platform firmware.

    With HEST off,

    ACPI HEST support disabled

    .
    .
    .

    aer 0000:00:01.0:pcie01: service driver aer loaded
    aer 0000:00:02.0:pcie01: service driver aer loaded
    aer 0000:00:03.0:pcie01: service driver aer loaded
    aer 0000:00:05.0:pcie01: service driver aer loaded
    aer 0000:00:07.0:pcie01: service driver aer loaded
    aer 0000:00:09.0:pcie01: service driver aer loaded

    Resolves BZ 547762.

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

diff --git a/drivers/acpi/hest.c b/drivers/acpi/hest.c
index e3dfee7..5556b34 100644
--- a/drivers/acpi/hest.c
+++ b/drivers/acpi/hest.c
@@ -3,6 +3,8 @@
 
 #define PREFIX "ACPI: "
 
+static int acpi_hest_enable = 1;
+
 static inline unsigned long parse_acpi_hest_ia_machine_check(struct acpi_hest_ia_machine_check *p)
 {
 	return sizeof(*p) +
@@ -123,6 +125,10 @@ int acpi_hest_firmware_first_pci(struct pci_dev *pci)
 {
 	acpi_status status = AE_NOT_FOUND;
 	struct acpi_table_header *hest = NULL;
+
+	if (!acpi_hest_enable)
+		return 0;
+
 	status = acpi_get_firmware_table("HEST", 1, ACPI_LOGICAL_ADDRESSING,
 					 (struct acpi_table_header **) &hest);
 
@@ -134,3 +140,14 @@ int acpi_hest_firmware_first_pci(struct pci_dev *pci)
 	return 0;
 }
 EXPORT_SYMBOL_GPL(acpi_hest_firmware_first_pci);
+
+static int __init acpi_hest(char *str)
+{
+	if (!strcmp(str, "off")) {
+		printk("ACPI HEST support disabled\n");
+		acpi_hest_enable = 0;
+	}
+
+	return 0;
+}
+__setup("acpi_hest=", acpi_hest);