On Mon, 16 Aug 2021, Jani Nikula <jani.nikula@xxxxxxxxxxxxxxx> wrote: > On Mon, 16 Aug 2021, Jackie Liu <liu.yun@xxxxxxxxx> wrote: >> Hi Jani. >> >> Your suggestion is that? >> >> diff --git a/drivers/gpu/drm/Kconfig b/drivers/gpu/drm/Kconfig >> index 7ff89690a976..ba179a539497 100644 >> --- a/drivers/gpu/drm/Kconfig >> +++ b/drivers/gpu/drm/Kconfig >> @@ -77,6 +77,7 @@ config DRM_DEBUG_SELFTEST >> config DRM_KMS_HELPER >> tristate >> depends on DRM >> + depends on FB if DRM_FBDEV_EMULATION >> help >> CRTC helpers for KMS drivers. >> >> >> But it has a syntax error. > > Ah, try this then: > > depends on FB || FB=n Or this monster: depends on FB || DRM_FBDEV_EMULATION=n > >> >> -- >> Thanks, BR, Jackie Liu >> >> 在 2021/8/16 下午4:33, Jani Nikula 写道: >>> On Mon, 16 Aug 2021, Jackie Liu <liu.yun@xxxxxxxxx> wrote: >>>> Hi Jani. >>>> >>>> My CI report an randconfigs build failed. there are: >>>> >>>> drm_fb_helper.c:(.text+0x302): undefined reference to `fb_set_suspend' >>>> drm_fb_helper.c:(.text+0xaea): undefined reference to `register_framebuffer' >>>> drm_fb_helper.c:(.text+0x1dcc): undefined reference to `framebuffer_alloc' >>>> ld: drm_fb_helper.c:(.text+0x1dea): undefined reference to `fb_alloc_cmap' >>>> ld: drm_fb_helper.c:(.text+0x1e2f): undefined reference to `fb_dealloc_cmap' >>>> ld: drm_fb_helper.c:(.text+0x1e5b): undefined reference to >>>> `framebuffer_release' >>>> drm_fb_helper.c:(.text+0x1e85): undefined reference to >>>> `unregister_framebuffer' >>>> drm_fb_helper.c:(.text+0x1ee9): undefined reference to `fb_dealloc_cmap' >>>> ld: drm_fb_helper.c:(.text+0x1ef0): undefined reference to >>>> `framebuffer_release' >>>> drm_fb_helper.c:(.text+0x1f96): undefined reference to >>>> `fb_deferred_io_cleanup' >>>> drm_fb_helper.c:(.text+0x203b): undefined reference to `fb_sys_read' >>>> drm_fb_helper.c:(.text+0x2051): undefined reference to `fb_sys_write' >>>> drm_fb_helper.c:(.text+0x208d): undefined reference to `sys_fillrect' >>>> drm_fb_helper.c:(.text+0x20bb): undefined reference to `sys_copyarea' >>>> drm_fb_helper.c:(.text+0x20e9): undefined reference to `sys_imageblit' >>>> drm_fb_helper.c:(.text+0x2117): undefined reference to `cfb_fillrect' >>>> drm_fb_helper.c:(.text+0x2172): undefined reference to `cfb_copyarea' >>>> drm_fb_helper.c:(.text+0x21cd): undefined reference to `cfb_imageblit' >>>> drm_fb_helper.c:(.text+0x2233): undefined reference to `fb_set_suspend' >>>> drm_fb_helper.c:(.text+0x22b0): undefined reference to `fb_set_suspend' >>>> drm_fb_helper.c:(.text+0x250f): undefined reference to `fb_deferred_io_init' >>>> >>>> The main reason is because DRM_FBDEV_EMULATION is built-in, and >>>> CONFIG_FB is compiled as a module. >>> >>> DRM_FBDEV_EMULATION is not a module, it's just a config >>> knob. drm_fb_helper.ko is the module, enabled via DRM_KMS_HELPER, and it >>> has an implicit dependency on FB, and DRM_FBDEV_EMULATION selects >>> DRM_KMS_HELPER. Select just breaks dependencies in all kinds of ways. >>> >>> This might help in config DRM_KMS_HELPER, and it might help the reader >>> because it's factual: >>> >>> depends on FB if DRM_FBDEV_EMULATION >>> >>> >>> BR, >>> Jani. >>> >>> >>> >>> >>> >>>> >>>> -- >>>> Jackie Liu >>>> >>>> 在 2021/8/16 下午3:01, Jani Nikula 写道: >>>>> On Mon, 16 Aug 2021, Jackie Liu <liu.yun@xxxxxxxxx> wrote: >>>>>> From: Jackie Liu <liuyun01@xxxxxxxxxx> >>>>>> >>>>>> When CONFIG_DRM_FBDEV_EMULATION is compiled to y and CONFIG_FB is m, the >>>>>> compilation will fail. we need make that dependency explicit. >>>>> >>>>> What's the failure mode? Using select here is a bad idea. >>>>> >>>>> BR, >>>>> Jani. >>>>> >>>>>> >>>>>> Reported-by: k2ci <kernel-bot@xxxxxxxxxx> >>>>>> Signed-off-by: Jackie Liu <liuyun01@xxxxxxxxxx> >>>>>> --- >>>>>> drivers/gpu/drm/Kconfig | 2 +- >>>>>> 1 file changed, 1 insertion(+), 1 deletion(-) >>>>>> >>>>>> diff --git a/drivers/gpu/drm/Kconfig b/drivers/gpu/drm/Kconfig >>>>>> index 7ff89690a976..346a518b5119 100644 >>>>>> --- a/drivers/gpu/drm/Kconfig >>>>>> +++ b/drivers/gpu/drm/Kconfig >>>>>> @@ -98,7 +98,7 @@ config DRM_DEBUG_DP_MST_TOPOLOGY_REFS >>>>>> config DRM_FBDEV_EMULATION >>>>>> bool "Enable legacy fbdev support for your modesetting driver" >>>>>> depends on DRM >>>>>> - depends on FB >>>>>> + select FB >>>>>> select DRM_KMS_HELPER >>>>>> select FB_CFB_FILLRECT >>>>>> select FB_CFB_COPYAREA >>>>> >>> -- Jani Nikula, Intel Open Source Graphics Center
