ACPI spec defines the bit and Microsoft uses it. Suppose Linux should use it too. Signed-off-by: Shaohua Li <shaohua.li@xxxxxxxxx> Index: 2.6.21-rc6/drivers/pci/pci-acpi.c =================================================================== --- 2.6.21-rc6.orig/drivers/pci/pci-acpi.c 2007-04-06 10:36:56.000000000 +0800 +++ 2.6.21-rc6/drivers/pci/pci-acpi.c 2007-04-25 10:58:12.000000000 +0800 @@ -317,6 +317,10 @@ static int __init acpi_pci_init(void) { int ret; + if (acpi_gbl_FADT.boot_flags & BAF_MSI_NOT_SUPPORTED) { + printk(KERN_INFO"ACPI FADT declares the system doesn't support MSI, so disable it\n"); + pci_no_msi(); + } ret = register_acpi_bus_type(&acpi_pci_bus); if (ret) return 0; Index: 2.6.21-rc6/include/acpi/actbl.h =================================================================== --- 2.6.21-rc6.orig/include/acpi/actbl.h 2007-04-06 10:36:56.000000000 +0800 +++ 2.6.21-rc6/include/acpi/actbl.h 2007-04-25 10:22:28.000000000 +0800 @@ -276,6 +276,7 @@ enum acpi_prefered_pm_profiles { #define BAF_LEGACY_DEVICES 0x0001 #define BAF_8042_KEYBOARD_CONTROLLER 0x0002 +#define BAF_MSI_NOT_SUPPORTED 0x0008 #define FADT2_REVISION_ID 3 #define FADT2_MINUS_REVISION_ID 2 - To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html