A link error related to DRM and fbdev

[Henry Wu]

Thanks for your reply. I will communicate with member of dri-devel further.

I tried to reproduce this issue on master branch and there was no link error:

...
  CC      arch/x86/boot/compressed/efi.o
  AS      arch/x86/boot/compressed/efi_mixed.o
  CC      arch/x86/boot/compressed/misc.o
  GZIP    arch/x86/boot/compressed/vmlinux.bin.gz
  MKPIGGY arch/x86/boot/compressed/piggy.S
  AS      arch/x86/boot/compressed/piggy.o
  LD      arch/x86/boot/compressed/vmlinux
  ZOFFSET arch/x86/boot/zoffset.h
  OBJCOPY arch/x86/boot/vmlinux.bin
  AS      arch/x86/boot/header.o
  LD      arch/x86/boot/setup.elf
  OBJCOPY arch/x86/boot/setup.bin
  BUILD   arch/x86/boot/bzImage
Kernel: arch/x86/boot/bzImage is ready  (#1)
$ cat .config | grep 'CONFIG_DRM_KMS\|CONFIG_FB\b\|FBDEV_EMUL'
CONFIG_DRM_KMS_HELPER=y
CONFIG_DRM_FBDEV_EMULATION=y
CONFIG_FB=m
$

In the attachments you can find two ".config".
kernel_config_515y_failed is used on branch 5.15.y (tag 5.15.157) and
kernel_config_master_succeed is what I used for master branch.

Masahiro Yamada <masahiroy at kernel.org> 于2024年5月7日周二 23:06写道：
>
> Fw: DRM list
>
> On Mon, May 6, 2024 at 2:53 PM Henry Wu <triangletrap12 at gmail.com> wrote:
> >
> > Hi, all.
> >
> > I found a link error related to DRM and fbdev on branch linux-5.15.y
> > (tag v5.15.157). It has same phenomenon with
> > https://lore.kernel.org/all/202303150232.MBonYhiv-lkp@intel.com/.
> >
> > I tried to investigate this issue and found that build will fail if
> > CONFIG_FB=m and it will succeed if CONFIG_FB=y.
> >
> > [user at localhost linux]$ cat .config | grep
> > 'CONFIG_DRM_KMS\|CONFIG_FB\b\|FBDEV_EMUL'
> > CONFIG_DRM_KMS_HELPER=y
> > CONFIG_DRM_FBDEV_EMULATION=y
> > CONFIG_FB=m
> > [user at localhost linux]$
> >
> > I'm not familiar with kbuild. Can anyone troubleshoot it further? You
> > can find .config from attachment.
>
>
> I do not have time to take a look at every build error,
> but somebody in the DRM list may help you.
>
>
>
> --
> Best Regards
> Masahiro Yamada