i915.ko depends upon the acpi/video.ko module and so refuses to load if ACPI is disabled at runtime if for example the BIOS is broken beyond repair. acpi/video provides an optional service for i915.ko and so we should just allow the modules to load, but do no nothing in order to let the machines boot correctly. Reported-by: Bill Augur <bill-auger@xxxxxxxxxxxxxx> Signed-off-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> Cc: Daniel Vetter <daniel.vetter@xxxxxxxx> Cc: Jani Nikula <jani.nikula@xxxxxxxxx> Cc: Zhang Rui <rui.zhang@xxxxxxxxx> Cc: "Rafael J. Wysocki" <rjw@xxxxxxxxxxxxx> Cc: Len Brown <lenb@xxxxxxxxxx> Cc: linux-acpi@xxxxxxxxxxxxxxx Cc: linux-kernel@xxxxxxxxxxxxxxx Cc: stable@xxxxxxxxxxxxxxx --- drivers/acpi/video.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/drivers/acpi/video.c b/drivers/acpi/video.c index debd30917010..3b76aef79a1c 100644 --- a/drivers/acpi/video.c +++ b/drivers/acpi/video.c @@ -2176,6 +2176,16 @@ EXPORT_SYMBOL(acpi_video_unregister_backlight); static int __init acpi_video_init(void) { + /* Let the module load even if ACPI is disabled (e.g. due to + * a broken BIOS) so that i915.ko can still be loaded on such + * old systems without an AcpiOpRegion. + * + * acpi_video_register() will report -ENODEV later as well due + * to acpi_disabled when i915.ko tries to register itself afterwards. + */ + if (acpi_disabled) + return 0; + dmi_check_system(video_dmi_table); if (intel_opregion_present()) -- 2.1.4 -- 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