Architectures others than x86 have a stub implementation calling WARN_ON_ONCE(). The appropriate headers need to be included, otherwise the header-test target will fail with: HDRTEST drivers/gpu/drm/i915/i915_mm.h In file included from <command-line>: ./drivers/gpu/drm/i915/i915_mm.h: In function ‘remap_io_mapping’: ./drivers/gpu/drm/i915/i915_mm.h:26:2: error: implicit declaration of function ‘WARN_ON_ONCE’ [-Werror=implicit-function-declaration] 26 | WARN_ON_ONCE(1); | ^~~~~~~~~~~~ v2: Do not include <linux/printk.h> since call to pr_err() has been removed Fixes: 67c430bbaae1 ("drm/i915: Skip remap_io_mapping() for non-x86 platforms") Cc: Siva Mullati <siva.mullati@xxxxxxxxx> Signed-off-by: Lucas De Marchi <lucas.demarchi@xxxxxxxxx> --- v3: No changes from previous version, just submitting to the right mailing list drivers/gpu/drm/i915/i915_mm.h | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/gpu/drm/i915/i915_mm.h b/drivers/gpu/drm/i915/i915_mm.h index 76f1d53bdf34..3ad22bbe80eb 100644 --- a/drivers/gpu/drm/i915/i915_mm.h +++ b/drivers/gpu/drm/i915/i915_mm.h @@ -6,6 +6,7 @@ #ifndef __I915_MM_H__ #define __I915_MM_H__ +#include <linux/bug.h> #include <linux/types.h> struct vm_area_struct; -- 2.35.0