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#1 2018-06-26 12:09:19

Beep
Member
Registered: 2018-05-17
Posts: 11

Distorted GRUB background wallpaper

This is in response to https://forums.bunsenlabs.org/viewtopic … 976#p73976

On my Lenovo G50-30 laptop the GRUB background image is displayed as an abstract collection of blobs:

vbthkHSn_t.jpg

I guess this may be related to the graphics card:

# lspci -vv
...
00:02.0 VGA compatible controller: Intel Corporation Atom Processor Z36xxx/Z37xxx Series Graphics & Display (rev 0c) (prog-if 00 [VGA controller])
	Subsystem: Lenovo Atom Processor Z36xxx/Z37xxx Series Graphics & Display
	Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx+
	Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
	Latency: 0
	Interrupt: pin A routed to IRQ 89
	Region 0: Memory at 90000000 (32-bit, non-prefetchable) [size=4M]
	Region 2: Memory at 80000000 (32-bit, prefetchable) [size=256M]
	Region 4: I/O ports at 3050 [size=8]
	[virtual] Expansion ROM at 000c0000 [disabled] [size=128K]
	Capabilities: [d0] Power Management version 2
		Flags: PMEClk- DSI+ D1- D2- AuxCurrent=0mA PME(D0-,D1-,D2-,D3hot-,D3cold-)
		Status: D0 NoSoftRst- PME-Enable- DSel=0 DScale=0 PME-
	Capabilities: [90] MSI: Enable+ Count=1/1 Maskable- 64bit-
		Address: fee0300c  Data: 41c1
	Capabilities: [b0] Vendor Specific Information: Len=07 <?>
	Kernel driver in use: i915
	Kernel modules: i915

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#2 2018-06-26 14:53:04

sleekmason
Member
Registered: 2018-05-22
Posts: 142

Re: Distorted GRUB background wallpaper

Please post the output of:

sudo lspci | grep VGA ; lsmod | grep "kms\|drm" ; find /dev -group video ; \
cat /proc/cmdline ; find /etc/modprobe.d/; cat /etc/modprobe.d/*kms* ; \
ls /etc/X11/xorg.conf ; glxinfo | grep -i "vendor\|rendering" ; \
grep LoadModule /var/log/Xorg.0.log

This will pretty much cover the spectrum of what might be needed to know for graphics.  In particular, I'm interested whether your hardware requires the i915g version to operate properly.

Last edited by sleekmason (2018-06-26 14:53:31)


"Nothing in the world can take the place of Persistence. Talent will not; nothing is more common than unsuccessful men with talent. Genius will not; unrewarded genius is almost a proverb. Education will not; the world is full of educated derelicts. Persistence and determination alone are omnipotent." - Calvin Coolidge

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#3 2018-06-26 18:17:05

twoion
ほやほや
Registered: 2015-08-10
Posts: 2,230

Re: Distorted GRUB background wallpaper

sleekmason wrote:

Please post the output of:

sudo lspci | grep VGA ; lsmod | grep "kms\|drm" ; find /dev -group video ; \
cat /proc/cmdline ; find /etc/modprobe.d/; cat /etc/modprobe.d/*kms* ; \
ls /etc/X11/xorg.conf ; glxinfo | grep -i "vendor\|rendering" ; \
grep LoadModule /var/log/Xorg.0.log

This will pretty much cover the spectrum of what might be needed to know for graphics.  In particular, I'm interested whether your hardware requires the i915g version to operate properly.

GRUB has nothing to do with Linux kernel/drivers/Xorg. The menu shown is rendered only using GRUB code (and drivers), though the exact type of graphics hardware would still be useful to know.

@OP: Is your system using EFI?


Im grünen Wald, dort wo die Drossel singt…

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#4 2018-06-26 18:58:25

sleekmason
Member
Registered: 2018-05-22
Posts: 142

Re: Distorted GRUB background wallpaper

GRUB has nothing to do with Linux kernel/drivers/Xorg. The menu shown is rendered only using GRUB code (and drivers), though the exact type of graphics hardware would still be useful to know.

Clarifying here,  would it not be important if he was using:

nomodeset i915.modeset=0

or some other bootline code?

Actually I don't think it's the driver.  My guess is that it may be as simple as:

Mark VGA/VBE/EFI FB as generic system framebuffer

Located in Bus Options

isn't enabled by default in the Bunsenlabs kernel.  years ago when newer devices came out, this was buggy.  But no longer.  It defaults through the different options, ultimately winding up with the simplest available legacy drivers.



Here's the kernel info on Mark VGA/VBE/EFI FB as generic system framebuffer:

CONFIG_X86_SYSFB:                                                                          │  
  │                                                                                            │  
  │ Firmwares often provide initial graphics framebuffers so the BIOS,                         │  
  │ bootloader or kernel can show basic video-output during boot for                           │  
  │ user-guidance and debugging. Historically, x86 used the VESA BIOS                          │  
  │ Extensions and EFI-framebuffers for this, which are mostly limited                         │  
  │ to x86.                                                                                    │  
  │ This option, if enabled, marks VGA/VBE/EFI framebuffers as generic                         │  
  │ framebuffers so the new generic system-framebuffer drivers can be                          │  
  │ used on x86. If the framebuffer is not compatible with the generic                         │  
  │ modes, it is adverticed as fallback platform framebuffer so legacy                         │  
  │ drivers like efifb, vesafb and uvesafb can pick it up.                                     │  
  │ If this option is not selected, all system framebuffers are always                         │  
  │ marked as fallback platform framebuffers as usual.                                         │  
  │                                                                                            │  
  │ Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will                         │  
  │ not be able to pick up generic system framebuffers if this option                          │  
  │ is selected. You are highly encouraged to enable simplefb as                               │  
  │ replacement if you select this option. simplefb can correctly deal                         │  
  │ with generic system framebuffers. But you should still keep vesafb                         │  
  │ and others enabled as fallback if a system framebuffer is                                  │  
  │ incompatible with simplefb.                                                                │  
  │                                                                                            │  
  │ If unsure, say Y.                                                                          │  
  │                                                                                            │  
  │ Symbol: X86_SYSFB [=n]                                                                     │  
  │ Type  : bool                                                                               │  
  │ Prompt: Mark VGA/VBE/EFI FB as generic system framebuffer                                  │  
  │   Location:                                                                                │  
  │     -> Bus options (PCI etc.)                                                              │  
  │   Defined at arch/x86/Kconfig:2842   
 

Also, the support for simple framebuffer is also disabled (located in Device Drivers --> Graphics-->frame buffer devices)

CONFIG_FB_SIMPLE:                                                                          │  
  │                                                                                            │  
  │ Say Y if you want support for a simple frame-buffer.                                       │  
  │                                                                                            │  
  │ This driver assumes that the display hardware has been initialized                         │  
  │ before the kernel boots, and the kernel will simply render to the                          │  
  │ pre-allocated frame buffer surface.                                                        │  
  │                                                                                            │  
  │ Configuration re: surface address, size, and format must be provided                       │  
  │ through device tree, or plain old platform data.                                           │  
  │                                                                                            │  
  │ Symbol: FB_SIMPLE [=n]                                                                     │  
  │ Type  : bool                                                                               │  
  │ Prompt: Simple framebuffer support                                                         │  
  │   Location:                                                                                │  
  │     -> Device Drivers                                                                      │  
  │       -> Graphics support                                                                  │  
  │         -> Frame buffer Devices                                                            │  
  │   Defined at drivers/video/fbdev/Kconfig:2333                                              │  
  │   Depends on: HAS_IOMEM [=y] && FB [=y]=y                                                  │  
  │   Selects: FB_CFB_FILLRECT [=y] && FB_CFB_COPYAREA [=y] && FB_CFB_IMAGEBLIT [=y]

Anyway, my guess is that without the first item being enabled, the op's framebuffer is falling back to legacy, and giving bad output. This would allow for everything to work correctly after boot, but have issues during. (You will note the driver says "if unsure, say yes" in the config).

I have noted this being enabled by default in other distros. The OP could try a recompile with those options enabled.  Pretty sure this is also what will allow for the pretty colors and such on the boot console smile

Last edited by sleekmason (2018-06-26 18:59:22)


"Nothing in the world can take the place of Persistence. Talent will not; nothing is more common than unsuccessful men with talent. Genius will not; unrewarded genius is almost a proverb. Education will not; the world is full of educated derelicts. Persistence and determination alone are omnipotent." - Calvin Coolidge

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#5 2018-06-26 20:48:44

Beep
Member
Registered: 2018-05-17
Posts: 11

Re: Distorted GRUB background wallpaper

sleekmason wrote:

Please post the output of:

sudo lspci | grep VGA ; lsmod | grep "kms\|drm" ; find /dev -group video ; \
cat /proc/cmdline ; find /etc/modprobe.d/; cat /etc/modprobe.d/*kms* ; \
ls /etc/X11/xorg.conf ; glxinfo | grep -i "vendor\|rendering" ; \
grep LoadModule /var/log/Xorg.0.log

Here goes...

$ sudo lspci | grep VGA ; lsmod | grep "kms\|drm" ; find /dev -group video ; \
> cat /proc/cmdline ; find /etc/modprobe.d/; cat /etc/modprobe.d/*kms* ; \
> ls /etc/X11/xorg.conf ; glxinfo | grep -i "vendor\|rendering" ; \
> grep LoadModule /var/log/Xorg.0.log
00:02.0 VGA compatible controller: Intel Corporation Atom Processor Z36xxx/Z37xxx Series Graphics & Display (rev 0c)
drm_kms_helper        155648  1 i915
drm                   360448  4 i915,drm_kms_helper
/dev/fb0
/dev/dri/card0
/dev/dri/renderD128
/dev/dri/controlD64
/dev/video0
BOOT_IMAGE=/boot/vmlinuz-4.9.0-6-amd64 root=UUID=93641644-ff00-4816-8a96-eda626b10298 ro quiet
/etc/modprobe.d/
/etc/modprobe.d/intel-microcode-blacklist.conf
/etc/modprobe.d/amd64-microcode-blacklist.conf
cat: '/etc/modprobe.d/*kms*': No such file or directory
ls: cannot access '/etc/X11/xorg.conf': No such file or directory
direct rendering: Yes
server glx vendor string: SGI
client glx vendor string: Mesa Project and SGI
    Vendor: Intel Open Source Technology Center (0x8086)
OpenGL vendor string: Intel Open Source Technology Center
[    22.850] (II) LoadModule: "glx"
[    23.651] (II) LoadModule: "modesetting"
[    23.667] (II) LoadModule: "fbdev"
[    23.670] (II) LoadModule: "vesa"
[    23.699] (II) LoadModule: "fbdevhw"
[    23.720] (II) LoadModule: "glamoregl"
[    24.090] (II) LoadModule: "fb"
[    25.543] (II) LoadModule: "libinput"
[    25.872] (II) LoadModule: "synaptics"
twoion wrote:

@OP: Is your system using EFI?

Nope

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#6 2018-06-26 21:06:16

ohnonot
...again
Registered: 2015-09-29
Posts: 3,198
Website

Re: Distorted GRUB background wallpaper

clearly grub recognizes and loads the image, but does not render it properly.
if the system is otherwise working fine, the problem/solution can only be within grub.
i'm not sure if there are options on __how__ the graphical terminal is set up and what sorts of images are loaded...
grub specialists, maybe the default setup can be tweaked to accomodate for such edge cases?
one person says the .tga format was better:
https://askubuntu.com/questions/893863/ … ge-in-grub

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#7 2018-06-27 16:15:17

sleekmason
Member
Registered: 2018-05-22
Posts: 142

Re: Distorted GRUB background wallpaper

ohnonot wrote:

clearly grub recognizes and loads the image, but does not render it properly.
if the system is otherwise working fine, the problem/solution can only be within grub.

Before grub. Framebuffer settings.

If however, you want to change the resolution during boot, you can:

xdpyinfo | grep dimensions

To get your screen dimensions, and then open /etc/default/grub and uncomment the line showing:

#GRUB_GFXMODE=

and change the existing numbers to match your screen size found using xdyinfo:

sudo nano /etc/default/grub

Example for my screen:

GRUB_GFXMODE=1440x900

Then update grub for the change to take affect:

update-grub

"Nothing in the world can take the place of Persistence. Talent will not; nothing is more common than unsuccessful men with talent. Genius will not; unrewarded genius is almost a proverb. Education will not; the world is full of educated derelicts. Persistence and determination alone are omnipotent." - Calvin Coolidge

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#8 2018-06-27 18:13:17

ohnonot
...again
Registered: 2015-09-29
Posts: 3,198
Website

Re: Distorted GRUB background wallpaper

sleekmason wrote:

Before grub. Framebuffer settings.

what is there before grub?
not sure if i understand, esp. since you go on recommending grub configuration stuff.

If however, you want to change the resolution during boot...

why is that about resolutions now?

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#9 2018-06-27 18:39:22

hhh
That's easy!
Registered: 2015-09-17
Posts: 6,118
Website

Re: Distorted GRUB background wallpaper

Moderator here; I'm editing the thread title to something a little more search-engine friendly.

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#10 2018-06-27 19:52:38

sleekmason
Member
Registered: 2018-05-22
Posts: 142

Re: Distorted GRUB background wallpaper

ohnonot wrote:

what is there before grub?
not sure if i understand, esp. since you go on recommending grub configuration stuff.

please read the description of Mark VGA/VBE/EFI FB as generic system framebuffer, that I wrote about a couple of posts up. 

I do not know for sure.  What I think, is that grub is reading the screen from the computers bios wrong.  Grub can set its own fonts, jpegs, and such, but ifgrub cannot set the picture format correctly, then it is because grub is using the screen settings from the bios, which may be giving a legacy output instead of reading the bios correctly, based on the above kernel setting not being enabled.

So do I know for sure?  Nope. Just suggesting a possible solution to the problem like everybody else. 

If however, you want to change the resolution during boot...

why is that about resolutions now?

Because I like helping people.  Showing one of the screen settings you can adjust from within grub seemed like a good idea. You made reference to settings within grub. Seemed relevant at the time.

Last edited by sleekmason (2018-06-27 19:53:03)


"Nothing in the world can take the place of Persistence. Talent will not; nothing is more common than unsuccessful men with talent. Genius will not; unrewarded genius is almost a proverb. Education will not; the world is full of educated derelicts. Persistence and determination alone are omnipotent." - Calvin Coolidge

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#11 2018-06-28 07:29:22

ohnonot
...again
Registered: 2015-09-29
Posts: 3,198
Website

Re: Distorted GRUB background wallpaper

going back to op #1.

this is something that happens before the kernel even gets loaded.
while there might be some kernel documentation that touches on the subject of bios framebuffers, the kernel has nothing to do with the problem at hand.

i previously suggested that bunsenlabs (or op) might consider using a background image that is compatible with as much hardware as possible.

i now found this:
https://wiki.debian.org/Grub/SplashImage
it suggests a very specific format for grub2.
i wonder if bunsenlabs' grub background conforms to that format.
Beep, could you please try to convert the background image to the exact format specified for grub2. does that work better?
if that doesn't work, could you try to convert the image to the format specified for grub1?

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#12 2018-06-28 10:13:27

johnraff
nullglob
From: Nagoya, Japan
Registered: 2015-09-09
Posts: 4,677
Website

Re: Distorted GRUB background wallpaper

ohnonot wrote:

i now found this:
https://wiki.debian.org/Grub/SplashImage
it suggests a very specific format for grub2.
i wonder if bunsenlabs' grub background conforms to that format.

That page seems a bit restrictive, compared with this: https://help.ubuntu.com/community/Grub2 … ound_Image or this: https://github.com/BunsenLabs/bunsen-im … efault.png Both are Ubuntu links, but is grub2 any different in Debian? JPG files are subject to some restrictions, but I thought our 640x480 PNG would be OK. If anyone can suggest how it can be improved then let's do it.


John
--------------------
( a boring Japan blog , Japan Links, idle twitterings  and GitStuff )
In case you forget, the rules.

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#13 2018-06-28 12:01:30

sleekmason
Member
Registered: 2018-05-22
Posts: 142

Re: Distorted GRUB background wallpaper

this is something that happens before the kernel even gets loaded.

While I understand this to be true after install, Doesn't the live kernel supply grub the initial screen settings that grub uses for it's settings on install from live cd? 

If the above code I referenced wasn't set by default in the live cd kernel version, Then the op's bios may not have been read correctly, and provided grub with the wrong initial settings. Don't be so quick to dismiss something because you are not familiar with it.

This can still be adjusted from userland.  The below from the grub manual might be what we are looking for. 

Maybe setting gfxpayload differently? Note, this is not the same as gfxmode.


15.1.13 gfxpayload

If this variable is set, it controls the video mode in which the Linux kernel starts up, replacing the ‘vga=’ boot option (see linux). It may be set to ‘text’ to force the Linux kernel to boot in normal text mode, ‘keep’ to preserve the graphics mode set using ‘gfxmode’, or any of the permitted values for ‘gfxmode’ to set a particular graphics mode (see gfxmode).

Depending on your kernel, your distribution, your graphics card, and the phase of the moon, note that using this option may cause GNU/Linux to suffer from various display problems, particularly during the early part of the boot sequence. If you have problems, set this variable to ‘text’ and GRUB will tell Linux to boot in normal text mode.

The default is platform-specific. On platforms with a native text mode (such as PC BIOS platforms), the default is ‘text’. Otherwise the default may be ‘auto’ or a specific video mode.

This variable is often set by ‘GRUB_GFXPAYLOAD_LINUX’ (see Simple configuration).

Maybe not, but worth looking at.

https://www.gnu.org/software/grub/manua … gfxpayload

Last edited by sleekmason (2018-06-28 12:02:58)


"Nothing in the world can take the place of Persistence. Talent will not; nothing is more common than unsuccessful men with talent. Genius will not; unrewarded genius is almost a proverb. Education will not; the world is full of educated derelicts. Persistence and determination alone are omnipotent." - Calvin Coolidge

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#14 2018-06-28 12:43:06

Beep
Member
Registered: 2018-05-17
Posts: 11

Re: Distorted GRUB background wallpaper

I've tried a few things...

  • I poked the BIOS. The only setting that looked relevant was Intel Virtual Technology, which was disabled. Enabling it didn't make a difference.

  • I exported the background PNG to a TGA as suggested at https://askubuntu.com/questions/893863/ … ge-in-grub. GRUB is using the new image but renders it as before.

  • I added GRUB_GFXPAYLOAD_LINUX="text" to my /etc/default/grub file (and ran update-grub). That didn't do anything either. I also ran videoinfo from the GRUB command line to see what modes are supported (as per https://www.gnu.org/software/grub/manua … ml#gfxmode) but that presented me with a black square box - it looks like it's using black text on a black background.

Not sure what else to try. It's not a major issue (I can live with no background image in GRUB) and it seems this is a very uncommon issue.

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#15 2018-06-28 12:49:51

sleekmason
Member
Registered: 2018-05-22
Posts: 142

Re: Distorted GRUB background wallpaper

I would try a reinstall to mbr to see if correct settings are picked up.

sudo grub-install /dev/sda

(For an sda drive)
then update grub

update-grub

**Edit - I don't know if reinstalling from here would change the settings.

Something you could try that would test the kernel code option, would be to install antix, and then grub from the antix live cd.  The afore mentioned support is enabled in their live cd kernel.

This isn't the most reliable of tests for all sorts of reasons, but may shed light on this part anyway:)

Last edited by sleekmason (2018-06-28 13:18:07)


"Nothing in the world can take the place of Persistence. Talent will not; nothing is more common than unsuccessful men with talent. Genius will not; unrewarded genius is almost a proverb. Education will not; the world is full of educated derelicts. Persistence and determination alone are omnipotent." - Calvin Coolidge

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#16 2018-06-28 15:22:04

hhh
That's easy!
Registered: 2015-09-17
Posts: 6,118
Website

Re: Distorted GRUB background wallpaper

Beep wrote:

GRUB background image is displayed as an abstract collection of blobs

Let's back up. You installed via the live image? And you had a normal grub screen there, you had the Beam wall and you could choose Live, Install, etc...?

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#17 2018-06-28 16:22:07

sleekmason
Member
Registered: 2018-05-22
Posts: 142

Re: Distorted GRUB background wallpaper

hhh wrote:

Let's back up. You installed via the live image? And you had a normal grub screen there, you had the Beam wall and you could choose Live, Install, etc...?

Excellent thought!  The only problem with this is that the initialization script readings are taken(unknown) directly from the bios before the session boots. 

As the "make grub" script is coming from a file within the distro image, any configuration Grub draws from would be after the initial kernel install, and likely the configuration would come from kernel land, rather than the beginning of the initialization script.

Everyone's bios is different, reading from a setting gathered by the kernel makes sense.  The file is always in the same path on all computers.

Edit** -- I thought I would try to outline this a bit easier.

It's basically like this,

1.Grub installs from the live cd.
2.The script to install grub is within the Bunsenlabs image on the cd.
3.Grub doesn't have everybody's bios info.  Doesn't have to.  Gets it from the settings the kernel obtained from the legacy drivers which "always work".

4.While they "always work" they can sometimes be buggy.
5.The kernel option I brought up provides a replacement to retrieving that very same screen information.  This is now considered a default "YES" option in the kernel.

6.If it doesn't work, it falls back to the legacy drivers.

Don't know how else to explain this.  I do not know either that this is the problem, however, enabling the first option above shows a major change in the way the screen looks on my computer, shrinking the font of the code displayed to a readable size during boot. Before boot, it would have to be baked in during install. 
Sorry If I've upset everybody.  That's all I can offer.  Generally instead of being picked apart for everything I say, people try to see my point of view.  This was mine, based on my experience.  I'll leave it go now.

Last edited by sleekmason (2018-06-28 20:36:18)


"Nothing in the world can take the place of Persistence. Talent will not; nothing is more common than unsuccessful men with talent. Genius will not; unrewarded genius is almost a proverb. Education will not; the world is full of educated derelicts. Persistence and determination alone are omnipotent." - Calvin Coolidge

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#18 2018-06-29 01:12:21

johnraff
nullglob
From: Nagoya, Japan
Registered: 2015-09-09
Posts: 4,677
Website

Re: Distorted GRUB background wallpaper

I think the installer's boot screen only uses grub if it's in efi mode - otherwise that menu is put up by isolinux.


John
--------------------
( a boring Japan blog , Japan Links, idle twitterings  and GitStuff )
In case you forget, the rules.

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#19 2018-06-29 02:26:51

ohnonot
...again
Registered: 2015-09-29
Posts: 3,198
Website

Re: Distorted GRUB background wallpaper

^ good point.

Beep, please keep us updated, if you feel like messing around with the image formats some more (or maybe some hidden, unknown grub settings).

____________________________________

sleekmason wrote:

Doesn't the live kernel supply grub the initial screen settings that grub uses for it's settings on install from live cd?

what? glasses 
grub's job is to load linux.
therefore, by definitoion, it cannot take any "supplies" from the kernel it is to load.
op's problem lies in either grub itself, or some setting saved on hard drive, or bios.
could be hardware trouble, but i find that unlikely, because the screenshot in post #1 clearly shows an image decoding problem (it's not garbled, the colors are reduced).

If the above code I referenced wasn't set by default in the live cd kernel version, Then the op's bios may not have been read correctly, and provided grub with the wrong initial settings. Don't be so quick to dismiss something because you are not familiar with it.

for heaven's sake.
i think we're going to have a lot of fun with you.

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#20 2018-06-29 03:44:41

tynman
Member
Registered: 2015-10-13
Posts: 72

Re: Distorted GRUB background wallpaper

I may not understand sleekmason's point properly, but my understanding of what he/she is saying is ...

Although grub doesn't get anything from the Linux kernel when grub is running -- because Linux isn't loaded yet -- ....

grub's configuration typically does happen while Linux is running (i.e., when we run the update-grub program). So it is plausible that grub gets info about your video card and/or screen geometry, etc. from Linux, and grub configures itself accordingly for the next time it's called during the next boot.

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#21 2018-06-29 10:13:41

sleekmason
Member
Registered: 2018-05-22
Posts: 142

Re: Distorted GRUB background wallpaper

tynman,  Thank you.

Let's start at the beginning.

You insert the Bunsenlabs cd.
ISOlinux magically reads your bios and sets your screen (try to forget that).
You START the live cd/installer and the kernel loads.
you install bunsenlabs.  yay!

Now you install grub to the mbr, right? WHERE does grub get the screen info?
From the running kernel when you booted the install cd. ...  Get it?
 
What gives grub those settings?
The legacy drivers for all the graphics cards provide this info to the bios, etc.
The legacy drivers are buggy.
Linus Torvalds et al. created a better way to get this info. (the first item in my second post.
This item SHOULD be enabled by default, as it does a better job.
If that item doesn't, the system falls back to the legacy drivers for the info.
I've tested the item above, and it allows for significant change.
I don't know if it will fix the op's problem.
Needs to be done anyway, with about twenty other pressing items.

How sleekmason?

Follow my guide (or any other you want!)
recompile the kernel with support for the above item.
unpack the iso.
switch kernels.
repack
enjoy the new method of retrieving all this info with a better boot screen and less graphics problems for the distro overall.

ohnonot.  Before grub.  Framebuffer.

tynman wrote:

Although grub doesn't get anything from the Linux kernel when grub is running -- because Linux isn't loaded yet -- ....

Exactly! Before the kernel loads the screen settings, grub depends on the settings it received during it's own install.  It is a bootloader, and must make sure that the first thing you see is readable. (now anyway).

grub's configuration typically does happen while Linux is running (i.e., when we run the update-grub program).

Yes, but grub can only control items within grub.

Thank you tynman for asking questions that illuminate.


I would much rather be explaining how the definitions provided in the kernel configuration file are not always accurate, or discuss better ways of implementing new features.  Thank you for your consideration.


"Nothing in the world can take the place of Persistence. Talent will not; nothing is more common than unsuccessful men with talent. Genius will not; unrewarded genius is almost a proverb. Education will not; the world is full of educated derelicts. Persistence and determination alone are omnipotent." - Calvin Coolidge

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#22 2018-06-30 12:52:05

sleekmason
Member
Registered: 2018-05-22
Posts: 142

Re: Distorted GRUB background wallpaper

I would like to clarify that any who would like to try this out themselves, can do so with no harm to their system.

Working with kernels is a great way to learn more about how Linux works.  The beauty of this is that IF a kernel fails after installation, just reboot into the old kernel and delete the offender!

You will need to download either the Debian Linux-Source from apt, or the stable (recommended) tarball package from the Linux Kernel Archives. (all in the guide).

All of the direction on how to get started are in the guide, with the fiddly bits being copy and paste.  It has never been easier to do this.

The kernel guide is: HERE


When you get to "make menuconfig" after "make oldconfig", Drop down to: 

Bus options (PCI etc.)  ---> and go to the end of the list, and enable

Mark VGA/VBE/EFI FB as generic system framebuffer

Save, exit, follow the guide to install. reboot.  Tell us how it went!

It is that simple, and this is one change out of many that could make your computer more stable, faster, and have better security.

On a note, When doing the "make oldconfig", you will see about 200-300 items flash by as you hold down the ENTER key.  These are all of the changes to the Linux Kernel since the last time it was updated.

Now this part is important, even while they are adding new and exciting features, (200-300 items flying past), they only enable those that are deemed absolutely safe, and won't disrupt a persons current settings.

All 200-300 items, have NEVER been checked, or they wouldn't exist in the "make oldconfig".  This also means that even BEFORE the current 4.9 kernel, there were changes that have never been addressed. Changing slab to slub should have been done 2014!


This includes the above code, new legacy drivers for nvidia, Changes in the allocator, general system calls that are deprecated and need to be removed, the addition of bfq as an option, debugging that the end user will NEVER use, security features unwarranted (anybody using yama over selinux?), staging drivers that keep getting added that just make the kernel bigger, and the list literally goes on and on.

Eventually, probably within a year or so, simply copying the Debian image won't cut it.  There are already a lot of changes that were not initially enabled, but since, have become the default.

Anybody that needs help with this should post in the kernel thread.  Unfortunately, the OP's problem has to be addressed before grub, so it won't change the initial problem without the fix being baked into the distro.  They can however, get a better boot display as it scrolls by by enabling the above.

I will always help anybody who needs it. Generally pretty damn fast.

tynman wrote:

but my understanding of what he/she is saying is ...

Ah, why not.  Male, age 50, wife, grandkids, backpacking, guitar, linux kernel.  I am a stone mason. My profile picture is of a drawing I made when I was 15 or so.  I think it tells a good story:)

ohnonot wrote:

for heaven's sake.
i think we're going to have a lot of fun with you.

I hope so!  I like you guys smile

Last edited by sleekmason (2018-06-30 13:01:36)


"Nothing in the world can take the place of Persistence. Talent will not; nothing is more common than unsuccessful men with talent. Genius will not; unrewarded genius is almost a proverb. Education will not; the world is full of educated derelicts. Persistence and determination alone are omnipotent." - Calvin Coolidge

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#23 2018-07-04 06:13:52

johnraff
nullglob
From: Nagoya, Japan
Registered: 2015-09-09
Posts: 4,677
Website

Re: Distorted GRUB background wallpaper

sleekmason wrote:

Doesn't the live kernel supply grub the initial screen settings that grub uses for it's settings on install from live cd?

No. The live system is self-contained, unpacked from a squashfs file and used for the live session. The live kernel is active then, but not at install time, when it's the Debian Installer kernel at work. During install, the live system files are copied into the new installed system, with some changes, like the grub and apt configuration which is handled by the installer. The live kernel then takes over on the reboot into the installed system, by which time it is unable to change the grub configuration, which was done by the debian-installer's grub-installer package.

BTW @Beep, I don't suppose running 'sudo update-grub' makes any difference to the grub screen?


John
--------------------
( a boring Japan blog , Japan Links, idle twitterings  and GitStuff )
In case you forget, the rules.

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#24 2018-07-04 11:37:05

sleekmason
Member
Registered: 2018-05-22
Posts: 142

Re: Distorted GRUB background wallpaper

Howdy Johnraff,

Thank you for responding.  So, to clarify, Where does grub get it's initial screen settings?

Since Grub is not part of the live squash file, The Debian kernel in the installer becomes active before install, creating all of the finished paths and other computer particulars.

Grub is also a part of that install package, and takes place after the Debian kernel has loaded, grabbing it's initial settings from the information provided by the Debian Kernel.

When you insert the live cd (et al), and choose to install, the Debian kernel is the first thing to boot.  Grub does not exist yet.  It gets installed last.

Grub doesn't create it's own initial parameters. It grabs them from the running kernel during install.


"Nothing in the world can take the place of Persistence. Talent will not; nothing is more common than unsuccessful men with talent. Genius will not; unrewarded genius is almost a proverb. Education will not; the world is full of educated derelicts. Persistence and determination alone are omnipotent." - Calvin Coolidge

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#25 2018-07-05 04:09:57

johnraff
nullglob
From: Nagoya, Japan
Registered: 2015-09-09
Posts: 4,677
Website

Re: Distorted GRUB background wallpaper

sleekmason wrote:

Where does grub get it's initial screen settings?

johnraff wrote:

...the grub configuration, which was done by the debian-installer's grub-installer package.

sleekmason wrote:

Grub doesn't create it's own initial parameters. It grabs them from the running kernel during install.

Grub doesn't run during install (except to display the EFI boot screen, which is quite separate). Grub's config is written during install. Grub itself runs at the next boot.

I think you might be slightly overemphasising the role played by the kernel here. The Debian Installer consists (mostly) of a lot of shell scripts, but it would be misleading to say that "grub is configured by the shell".

---
Meanwhile, @Beep's problem is no nearer solution.

@Beep, how about if you set a different image altogether? Does everything look like that?


John
--------------------
( a boring Japan blog , Japan Links, idle twitterings  and GitStuff )
In case you forget, the rules.

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