Arnd Bergmann wrote: > On Wed, Feb 2, 2022 at 1:14 AM Thinh Nguyen wrote: >> Fabio Estevam wrote: >>> On Tue, Feb 1, 2022 at 8:06 PM Randy Dunlap wrote: >>>> >>>> On 2/1/22 15:01, Thinh Nguyen wrote: >>>>> Hi, >>>>> >>>>> One of our test setups is unable to boot (stuck at initramfs). Git >>>>> bisection points to the commit below: >>>>> >>>>> f611b1e7624c ("drm: Avoid circular dependencies for CONFIG_FB") >>>>> >>>>> Reverting this patch resolves the issue. This issue persists in mainline >>>>> also. Unfortunately there isn't any meaningful log. Hopefully someone >>>>> can give some insight as to what could be the issue and revert/fix this >>>>> issue. >>>> >>>> Hi, >>>> Did you enable DRM_FBDEV_EMULATION? >> >> I did not enable it. >> >>>> Please provide the failing .config file. >>> >>> Does selecting CONFIG_FB=y help? >>> >> >> On the config that has the issue, this isn't set. After reverting the >> commit above, this was set. Maybe this is what's needed? I need to test it. > > CONFIG_FB should not normally be needed for booting, so unless > you have a graphical application in your initramfs that requires the /dev/fb0 > device to work, it is not supposed to make a difference. > I'm not sure, but it seems like the setup we have isn't the only one that needed it. Fabio also noted that the imx_v6_v7_defconfig also needs to have CONFIG_FB set. > Are there any other differences in your .config before and after the patch? > It's possible that you use some other driver that in turn depends on > CONFIG_FB. Does your machine have any graphical output device? > If yes, which driver do you use? I don't have the answer to those questions yet. Need more investigation. I'm new to this particular test setup. > > You may also want to make sure that you have 9d6366e743f3 ("drm: > fb_helper: improve CONFIG_FB dependency") in your kernel, which > fixes a minor problem with my original patch. > > Arnd The issue also occurs in mainline, which has your minor fix commit above. The revert isn't clean for the latest kernel version. I also have to revert some of the changes along with CONFIG_FB. The revert looks more like this for the latest kernel: diff --git a/drivers/gpu/drm/Kconfig b/drivers/gpu/drm/Kconfig index b1f22e457fd0..7cbc733a8569 100644 --- a/drivers/gpu/drm/Kconfig +++ b/drivers/gpu/drm/Kconfig @@ -118,8 +118,9 @@ config DRM_DEBUG_MODESET_LOCK config DRM_FBDEV_EMULATION bool "Enable legacy fbdev support for your modesetting driver" - depends on DRM_KMS_HELPER - depends on FB=y || FB=DRM_KMS_HELPER + depends on DRM + select DRM_KMS_HELPER + select FB select FB_CFB_FILLRECT select FB_CFB_COPYAREA select FB_CFB_IMAGEBLIT I attached the configs for kernel v5.17-rc1. The "bad" config is without any revert, the "good" config is with the change above. Thanks, Thinh