Paging in Arnd on this one, as he builds a lot of next kernels and randconfigs.

On Wed, Oct 18, 2017 at 12:55 PM, kbuild test robot fengguang.wu@intel.com wrote:

tree: https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master head: a7dd40274d75326ca868479c62090b1198a357ad commit: 001485d5255cb17e99aa9e3712e43865b92d6adc [520/6567] drm/pl111: Replace custom connector with panel bridge config: x86_64-randconfig-ws0-10181652 (attached as .config) compiler: gcc-6 (Debian 6.2.0-3) 6.2.0 20160901 reproduce: git checkout 001485d5255cb17e99aa9e3712e43865b92d6adc # save the attached .config to linux build tree make ARCH=x86_64

All warnings (new ones prefixed by >>):

warning: (DRM_STM && DRM_VC4 && DRM_PL111 && DRM_TVE200 && DRM_LVDS_ENCODER && DRM_DW_MIPI_DSI) selects DRM_PANEL_BRIDGE which has unmet direct dependencies (HAS_IOMEM && DRM_BRIDGE && DRM_KMS_HELPER)

I have a real hard time deciphering this Kconfig problem.

Can someone help?

What I see it that DTM_STM, DRM_VC4, DRM_PL111, DRM_TVE200 and DRM_DW_MIPI_DSI all select DRM_PANEL_BRIDGE and DRM_KMS_HELPER.

DRM_LVDS_ENCODER select DRM_PANEL_BRIDGE

So they seem to select what they need.

HAS_IOMEM must be the real culprit, and it is not set in the .config attached.

So is the real problem that the bot is compiling a config without HAS_IOMEM and we should put a depends on HAS_IOMEM somewhere?

This HAS_IOMEM business keep annoying me, UML has this problem a lot since it doesn't have iomem for sure, but this randconfig wants to build an x86_64 without iomem and is not pestering us about it.

Is building for x86_64 without iomem really a problem we should be addressing?

I think there are tons of problems in the kernel related to the depends on HAS_IOMEM being missing, we can go fixing that forever I think.

Yours, Linus Walleij