Bug 121411

Summary:	fbset gets 'ioctl FBIOPUT_VSCREENINFO: Invalid argument'
Product:	Drivers	Reporter:	Mathieu Malaterre (mathieu.malaterre)
Component:	Video(Other)	Assignee:	drivers_video-other
Status:	NEW ---
Severity:	normal	CC:	rbthomas, sudipm.mukherjee
Priority:	P1
Hardware:	PPC-64
OS:	Linux
URL:	https://bugs.debian.org/800005
Kernel Version:	3.16	Subsystem:
Regression:	Yes	Bisected commit-id:

Description Mathieu Malaterre 2016-07-04 09:35:48 UTC

As described in the original Debian bug report, a user fails to run a simple `fbset` command. Turnning drm.debug=0x3f does not show the root of the failure making it impossible to track the issue.

Comment 1 Mathieu Malaterre 2016-07-04 09:38:10 UTC

> rbthomas@bigal:~$ dmesg > /tmp/dmesg-before.out
>
> rbthomas@bigal:~$ fbset
>
> mode "1680x1050"
>     geometry 1680 1050 1680 1050 32
>     timings 0 0 0 0 0 0 0
>     accel true
>     rgba 8/16,8/8,8/0,0/0
> endmode
>
> rbthomas@bigal:~$ fbset 800x600-60
> ioctl FBIOPUT_VSCREENINFO: Invalid argument
> rbthomas@bigal:~$ grep 800x600 /etc/fb.modes
> #     800x600, 48 Hz, Interlaced (36.00 MHz dotclock)
> mode "800x600-48-lace"
> #     800x600, 56 Hz, Non-Interlaced (36.00 MHz dotclock)
> mode "800x600-56"
> #     800x600, 60 Hz, Non-Interlaced (40.00 MHz dotclock)
> mode "800x600-60"
> #     800x600, 70 Hz, Non-Interlaced (44.90 MHz dotclock)
> mode "800x600-70"
> #     800x600, 72 Hz, Non-Interlaced (50.00 MHz dotclock)
> mode "800x600-72"
> #     800x600, 75 Hz, Non-Interlaced (49.50 MHz dotclock)
> mode "800x600-75"
> #     800x600, 90 Hz, Non-Interlaced (56.64 MHz dotclock)
> mode "800x600-90"
> #     800x600, 100 Hz, Non-Interlaced (67.50 MHz dotclock)
> mode “800x600-100"
>
> rbthomas@bigal:~$ dmesg > /tmp/dmesg-after.out
>
> rbthomas@bigal:~$ diff /tmp/dmesg-before.out /tmp/dmesg-after.out
>
> rbthomas@bigal:~$ cat /proc/cmdline
> root=/dev/mapper/bigal-root ro drm.debug=0xe
>
> rbthomas@bigal:~$ lsmod | grep drm
> drm_kms_helper         82001  1 nouveau
> drm                   325466  6 ttm,drm_kms_helper,nouveau,sil164
> agpgart                39217  2 drm,ttm
> i2c_core               31058  10
> drm,i2c_powermac,windfarm_smu_sat,drm_kms_helper,
>                                 
>                                  i2c_algo_bit,windfarm_lm75_sensor,nouveau,sil164,
>                                  windfarm_max6690_sensor,snd_aoa_codec_onyx

Comment 2 Rick Thomas 2016-07-05 08:46:54 UTC

Thanks!  I’ll give them a couple of days to respond, then bring it to their attention and offer to help with testing if they are willing to take it on.

Thanks very much for all your help so far!
Enjoy!
Rick

On Jul 5, 2016, at 12:54 AM, bugzilla-daemon@bugzilla.kernel.org wrote:

> https://bugzilla.kernel.org/show_bug.cgi?id=121411
> 
> Mathieu Malaterre <mathieu.malaterre@gmail.com> changed:
> 
>           What    |Removed                     |Added
> ----------------------------------------------------------------------------
>                 CC|                            |rbthomas@pobox.com
> 
> -- 
> You are receiving this mail because:
> You are on the CC list for the bug.

Comment 3 Sudip 2019-12-27 14:25:02 UTC

This is reproducible on v5.4.6 also. I did a little more debugging and looks like that since the bpp of the emulated framebuffer can not be changed. In my testing I had to add a compatible mode in fb.modes file with the same bpp and fbset worked again.