agp/hp: fail gracefully if we don't find an IOC

Bail out if we don't find an enclosing IOC. Previously, if we didn't find one, we tried to set things up using garbage for the SBA/IOC register address, which causes a crash. This crash only happens if firmware supplies a defective ACPI namespace, so it doesn't fix any problems in the field. Signed-off-by: Bjorn Helgaas <[email protected]> Signed-off-by: Dave Airlie <[email protected]>
mrcsosa · Jan 11, 2010 · 3d4a788 · 3d4a788
1 parent 67fe63b
commit 3d4a788
Showing 1 changed file with 3 additions and 0 deletions.
diff --git a/drivers/char/agp/hp-agp.c b/drivers/char/agp/hp-agp.c
@@ -508,6 +508,9 @@ zx1_gart_probe (acpi_handle obj, u32 depth, void *context, void **ret)
 		handle = parent;
 	} while (ACPI_SUCCESS(status));
 
+	if (ACPI_FAILURE(status))
+		return AE_OK;	/* found no enclosing IOC */
+
 	if (hp_zx1_setup(sba_hpa + HP_ZX1_IOC_OFFSET, lba_hpa))
 		return AE_OK;