LiveCD bootloader

LiveCD bootloader

[Teresa e Junior]

Hello, GRUB developers!

I'm fighting to replace isolinux with GRUB2 in the Live System I'm
about to release. I already got the CD to boot with GRUB2, generating
the ISO with grub-mkrescue. I think there must be some smarter way to
do this, but I can't find out.

But due to some features I need (not the eyecandy), I noticed the CD
only boots without gfx support (which is the most important for me).

I already tried using --modules="linux ext2 fshelp ls boot pc coreui vbe
png jpeg gettext gfxmode" without any success. Tried some burg-mkisofs
and xorriso commands, but I believe I miss something. Typing
`configfile /grub.cfg' won't help either.

Your help will be very appreciated, for we've been struggling for not
a few hours!

Teresa e Junior

Re: LiveCD bootloader

[Brendan Trotter]

Hi,

On Wed, Sep 8, 2010 at 12:12 PM, Teresa e Junior
<teresaejunior@gmail.com> wrote:
> But due to some features I need (not the eyecandy), I noticed the CD
> only boots without gfx support (which is the most important for me).

You can't really safely use graphics support in a Live-CD anyway.

GRUB and Linux use "video mode numbers" to request a video mode. These
video mode numbers can be different for different video cards. Early
versions of VBE did define some standard mode numbers, but these
became obsolete in VBE version 2.0 (back in 1994). Software written
after 1994 shouldn't rely on these obsolete video mode numbers. For
example, if you're lucky mode 0x118 might be 1024*768 with 24-BPP, but
nothing guarantees that anymore, and it could easily be any other
video mode. There's also no guarantee that the the video card supports
the video mode (e.g. a lot of video cards only support 32-BPP video
modes and don't support any 24-BPP video modes; and some only support
24-BPP video modes and not 32-BPP video modes; and the same is true
for 15-BPP vs. 16-BPP).

Finally, even if you're lucky and VBE does support the video mode (and
it's the right one, not something else); there's no guarantee that the
monitor also supports the video mode (neither VBE nor GRUB nor Linux
bother the check the monitors EDID information to make sure). This can
be worse than "user can't see anything. For some (very old) "VGA only"
monitors exceeding the monitor's maximum timing frequencies can cause
the monitor to blow up (but these are quite rare now, for obvious
reasons). I've also heard rumours that for some LCDs built into
cheaper notebook type devices, exceeding the screen's maximum timing
frequencies can cause permanent damage.

Basically, the entire thing only works when the user tells GRUB/Linux
which video mode to use (and then it's the user's fault if they choose
something that doesn't work). It fails for a Live-CD which is meant to
work "as is" and isn't pre-configured by the user.

The only "least likely to fail" option would be to use standard VGA
video modes instead - e..g mode 0x12 (320*200*256 colours) or mode
0x13 (640*480*16 colours). These mode numbers are "guaranteed" (by VGA
compatibility) to be what you asked for, and are also "guaranteed" to
work with the monitor (by VGA compatibility for older monitors and by
VESA's "Safe Mode Timing" specification for newer monitors).
Unfortunately they also suck - very low resolution and/or poor colour
depth.

Of course, I'm not saying that you can't unsafely use graphics support
in a Live-CD - I'm sure plenty of people have done worse.



Cheers,

Brendan

Re: LiveCD bootloader

[Brendan Trotter]

Hi,

On Wed, Sep 8, 2010 at 2:39 PM, Brendan Trotter <btrotter@gmail.com> wrote:
> GRUB and Linux use "video mode numbers" to request a video mode. These
> video mode numbers can be different for different video cards. Early
> versions of VBE did define some standard mode numbers, but these
> became obsolete in VBE version 2.0 (back in 1994). Software written
> after 1994 shouldn't rely on these obsolete video mode numbers. For
> example, if you're lucky mode 0x118 might be 1024*768 with 24-BPP, but
> nothing guarantees that anymore, and it could easily be any other
> video mode. There's also no guarantee that the the video card supports
> the video mode (e.g. a lot of video cards only support 32-BPP video
> modes and don't support any 24-BPP video modes; and some only support
> 24-BPP video modes and not 32-BPP video modes; and the same is true
> for 15-BPP vs. 16-BPP).

My apologies.

It seems GRUB2 has improved a lot, and doesn't rely on the obsolete
"standard video mode numbers" anymore. Except for problems caused by
video modes that are supported by the video card but not supported by
the monitor; it's mostly only a problem with Linux itself now.


Cheers,

Brendan

Re: LiveCD bootloader

[Robert Millan]

2010/9/8, Brendan Trotter <btrotter@gmail.com>:
> My apologies.
>
> It seems GRUB2 has improved a lot, and doesn't rely on the obsolete
> "standard video mode numbers" anymore. Except for problems caused by
> video modes that are supported by the video card but not supported by
> the monitor; it's mostly only a problem with Linux itself now.

Not with Linux either, just "set gfxpayload=keep" and GRUB will preserve
video mode when giving control to Linux.

-- 
Robert Millan

Re: LiveCD bootloader

[Teresa e Junior]

On Wed, 8 Sep 2010 14:54:25 +0930
Brendan Trotter <btrotter@gmail.com> wrote:

> Hi,
> 
> On Wed, Sep 8, 2010 at 2:39 PM, Brendan Trotter <btrotter@gmail.com>
> wrote:
> > GRUB and Linux use "video mode numbers" to request a video mode.
> > These video mode numbers can be different for different video
> > cards. Early versions of VBE did define some standard mode numbers,
> > but these became obsolete in VBE version 2.0 (back in 1994).
> > Software written after 1994 shouldn't rely on these obsolete video
> > mode numbers. For example, if you're lucky mode 0x118 might be
> > 1024*768 with 24-BPP, but nothing guarantees that anymore, and it
> > could easily be any other video mode. There's also no guarantee
> > that the the video card supports the video mode (e.g. a lot of
> > video cards only support 32-BPP video modes and don't support any
> > 24-BPP video modes; and some only support 24-BPP video modes and
> > not 32-BPP video modes; and the same is true for 15-BPP vs. 16-BPP).
> 
> My apologies.
> 
> It seems GRUB2 has improved a lot, and doesn't rely on the obsolete
> "standard video mode numbers" anymore. Except for problems caused by
> video modes that are supported by the video card but not supported by
> the monitor; it's mostly only a problem with Linux itself now.
> 
> 
> Cheers,
> 
> Brendan
> 
> _______________________________________________
> Grub-devel mailing list
> Grub-devel@gnu.org
> http://lists.gnu.org/mailman/listinfo/grub-devel

Thanks! We have to set 640x480 as default anyway...

Re: LiveCD bootloader

[Vladimir 'φ-coder/phcoder' Serbinenko]

On 09/09/10 00:47, Teresa e Junior wrote:
> On Wed, 8 Sep 2010 14:54:25 +0930
> Brendan Trotter<btrotter@gmail.com>  wrote:
>
>    
>> Hi,
>>
>> On Wed, Sep 8, 2010 at 2:39 PM, Brendan Trotter<btrotter@gmail.com>
>> wrote:
>>      
>>> GRUB and Linux use "video mode numbers" to request a video mode.
>>> These video mode numbers can be different for different video
>>> cards. Early versions of VBE did define some standard mode numbers,
>>> but these became obsolete in VBE version 2.0 (back in 1994).
>>> Software written after 1994 shouldn't rely on these obsolete video
>>> mode numbers. For example, if you're lucky mode 0x118 might be
>>> 1024*768 with 24-BPP, but nothing guarantees that anymore, and it
>>> could easily be any other video mode. There's also no guarantee
>>> that the the video card supports the video mode (e.g. a lot of
>>> video cards only support 32-BPP video modes and don't support any
>>> 24-BPP video modes; and some only support 24-BPP video modes and
>>> not 32-BPP video modes; and the same is true for 15-BPP vs. 16-BPP).
>>>        
>> My apologies.
>>
>> It seems GRUB2 has improved a lot, and doesn't rely on the obsolete
>> "standard video mode numbers" anymore. Except for problems caused by
>> video modes that are supported by the video card but not supported by
>> the monitor; it's mostly only a problem with Linux itself now.
>>
>>
>> Cheers,
>>
>> Brendan
>>
>> _______________________________________________
>> Grub-devel mailing list
>> Grub-devel@gnu.org
>> http://lists.gnu.org/mailman/listinfo/grub-devel
>>      
> Thanks! We have to set 640x480 as default anyway...
>
>    
You can specify multiple comma-separated possibilities in order of 
priorities
> _______________________________________________
> Grub-devel mailing list
> Grub-devel@gnu.org
> http://lists.gnu.org/mailman/listinfo/grub-devel
>
>    


-- 
Regards
Vladimir 'φ-coder/phcoder' Serbinenko

Re: LiveCD bootloader

[Teresa e Junior]

On Thu, 09 Sep 2010 00:52:27 +0200
Vladimir 'φ-coder/phcoder' Serbinenko <phcoder@gmail.com> wrote:

> On 09/09/10 00:47, Teresa e Junior wrote:
> > On Wed, 8 Sep 2010 14:54:25 +0930
> > Brendan Trotter<btrotter@gmail.com>  wrote:
> >
> >    
> >> Hi,
> >>
> >> On Wed, Sep 8, 2010 at 2:39 PM, Brendan Trotter<btrotter@gmail.com>
> >> wrote:
> >>      
> >>> GRUB and Linux use "video mode numbers" to request a video mode.
> >>> These video mode numbers can be different for different video
> >>> cards. Early versions of VBE did define some standard mode
> >>> numbers, but these became obsolete in VBE version 2.0 (back in
> >>> 1994). Software written after 1994 shouldn't rely on these
> >>> obsolete video mode numbers. For example, if you're lucky mode
> >>> 0x118 might be 1024*768 with 24-BPP, but nothing guarantees that
> >>> anymore, and it could easily be any other video mode. There's
> >>> also no guarantee that the the video card supports the video mode
> >>> (e.g. a lot of video cards only support 32-BPP video modes and
> >>> don't support any 24-BPP video modes; and some only support
> >>> 24-BPP video modes and not 32-BPP video modes; and the same is
> >>> true for 15-BPP vs. 16-BPP). 
> >> My apologies.
> >>
> >> It seems GRUB2 has improved a lot, and doesn't rely on the obsolete
> >> "standard video mode numbers" anymore. Except for problems caused
> >> by video modes that are supported by the video card but not
> >> supported by the monitor; it's mostly only a problem with Linux
> >> itself now.
> >>
> >>
> >> Cheers,
> >>
> >> Brendan
> >>
> >> _______________________________________________
> >> Grub-devel mailing list
> >> Grub-devel@gnu.org
> >> http://lists.gnu.org/mailman/listinfo/grub-devel
> >>      
> > Thanks! We have to set 640x480 as default anyway...
> >
> >    
> You can specify multiple comma-separated possibilities in order of 
> priorities
> > _______________________________________________
> > Grub-devel mailing list
> > Grub-devel@gnu.org
> > http://lists.gnu.org/mailman/listinfo/grub-devel
> >
> >    
> 
> 

Hello, Vladimir!

What do you mean with that? Let us suppose, I set:

GRUB_GFXMODE=1280x800,1024x768,640x480

and if the hardware supports the first, it will use the first, and so
forth?

Thank you!
Teresa e Junior

Re: LiveCD bootloader

[Vladimir 'φ-coder/phcoder' Serbinenko]

On 09/09/10 01:00, Teresa e Junior wrote:
> On Thu, 09 Sep 2010 00:52:27 +0200
> Vladimir 'φ-coder/phcoder' Serbinenko<phcoder@gmail.com>  wrote:
>
>    
>> On 09/09/10 00:47, Teresa e Junior wrote:
>>      
>>> On Wed, 8 Sep 2010 14:54:25 +0930
>>> Brendan Trotter<btrotter@gmail.com>   wrote:
>>>
>>>
>>>        
>>>> Hi,
>>>>
>>>> On Wed, Sep 8, 2010 at 2:39 PM, Brendan Trotter<btrotter@gmail.com>
>>>> wrote:
>>>>
>>>>          
>>>>> GRUB and Linux use "video mode numbers" to request a video mode.
>>>>> These video mode numbers can be different for different video
>>>>> cards. Early versions of VBE did define some standard mode
>>>>> numbers, but these became obsolete in VBE version 2.0 (back in
>>>>> 1994). Software written after 1994 shouldn't rely on these
>>>>> obsolete video mode numbers. For example, if you're lucky mode
>>>>> 0x118 might be 1024*768 with 24-BPP, but nothing guarantees that
>>>>> anymore, and it could easily be any other video mode. There's
>>>>> also no guarantee that the the video card supports the video mode
>>>>> (e.g. a lot of video cards only support 32-BPP video modes and
>>>>> don't support any 24-BPP video modes; and some only support
>>>>> 24-BPP video modes and not 32-BPP video modes; and the same is
>>>>> true for 15-BPP vs. 16-BPP).
>>>>>            
>>>> My apologies.
>>>>
>>>> It seems GRUB2 has improved a lot, and doesn't rely on the obsolete
>>>> "standard video mode numbers" anymore. Except for problems caused
>>>> by video modes that are supported by the video card but not
>>>> supported by the monitor; it's mostly only a problem with Linux
>>>> itself now.
>>>>
>>>>
>>>> Cheers,
>>>>
>>>> Brendan
>>>>
>>>> _______________________________________________
>>>> Grub-devel mailing list
>>>> Grub-devel@gnu.org
>>>> http://lists.gnu.org/mailman/listinfo/grub-devel
>>>>
>>>>          
>>> Thanks! We have to set 640x480 as default anyway...
>>>
>>>
>>>        
>> You can specify multiple comma-separated possibilities in order of
>> priorities
>>      
>>> _______________________________________________
>>> Grub-devel mailing list
>>> Grub-devel@gnu.org
>>> http://lists.gnu.org/mailman/listinfo/grub-devel
>>>
>>>
>>>        
>>
>>      
> Hello, Vladimir!
>
> What do you mean with that? Let us suppose, I set:
>
> GRUB_GFXMODE=1280x800,1024x768,640x480
>
> and if the hardware supports the first, it will use the first, and so
> forth?
>
>    
yes
> Thank you!
> Teresa e Junior
>
> _______________________________________________
> Grub-devel mailing list
> Grub-devel@gnu.org
> http://lists.gnu.org/mailman/listinfo/grub-devel
>
>    


-- 
Regards
Vladimir 'φ-coder/phcoder' Serbinenko

Re: LiveCD bootloader

[Teresa e Junior]

On Thu, 09 Sep 2010 01:29:09 +0200
Vladimir 'φ-coder/phcoder' Serbinenko <phcoder@gmail.com> wrote:

> yes

Thanks again!

Re: LiveCD bootloader

[Brendan Trotter]

Hi,

On Thu, Sep 9, 2010 at 8:30 AM, Teresa e Junior <teresaejunior@gmail.com> wrote:
> What do you mean with that? Let us suppose, I set:
>
> GRUB_GFXMODE=1280x800,1024x768,640x480
>
> and if the hardware supports the first, it will use the first, and so
> forth?

Not all of my previous assumptions were obsolete (and this time I
checked the source code for GRUB2 to make sure).

If the video card and software supports the first video mode then GRUB
will use the first video mode; regardless of whether or not the
monitor itself supports the video mode.

This means that: for the monitors I have here; for the newest 3 (LCD)
monitors you'll get 1280x800 and it will work fine (although probably
a little blurry due to not using the native resolution of any of the
monitor's); for the largest CRT you'll probably get a squashed image
that might still be readable (within the monitors maximum frequency,
but unsupported aspect ratio); for the next CRT you'll get a black
screen with an error message from the on screen display; for the next
2 CRTs you'll get an unreadable (flickering/rolling) mess; and for the
last monitor (a very old CRT) you'll probably cause permanent damage.


Cheers,

Brendan

Re: LiveCD bootloader

[Vladimir 'φ-coder/phcoder' Serbinenko]

On 09/09/10 03:33, Brendan Trotter wrote:
> Hi,
>
> On Thu, Sep 9, 2010 at 8:30 AM, Teresa e Junior<teresaejunior@gmail.com>  wrote:
>    
>> What do you mean with that? Let us suppose, I set:
>>
>> GRUB_GFXMODE=1280x800,1024x768,640x480
>>
>> and if the hardware supports the first, it will use the first, and so
>> forth?
>>      
> Not all of my previous assumptions were obsolete (and this time I
> checked the source code for GRUB2 to make sure).
>
> If the video card and software supports the first video mode then GRUB
> will use the first video mode; regardless of whether or not the
> monitor itself supports the video mode.
>    
GRUB uses VBE on real hardware (I have some intelfb code but it's not 
functional yet), in this case it's VBE responsibility to verify monitor 
capabilities. Even having EDID without knowing the card characteristics 
you can't really check it since card itself may perform 
post-transformations like stretching or splitting the image among monitors.
> This means that: for the monitors I have here; for the newest 3 (LCD)
> monitors you'll get 1280x800 and it will work fine (although probably
> a little blurry due to not using the native resolution of any of the
> monitor's); for the largest CRT you'll probably get a squashed image
> that might still be readable (within the monitors maximum frequency,
> but unsupported aspect ratio); for the next CRT you'll get a black
> screen with an error message from the on screen display; for the next
> 2 CRTs you'll get an unreadable (flickering/rolling) mess; and for the
> last monitor (a very old CRT) you'll probably cause permanent damage.
>
>
> Cheers,
>
> Brendan
>
> _______________________________________________
> Grub-devel mailing list
> Grub-devel@gnu.org
> http://lists.gnu.org/mailman/listinfo/grub-devel
>
>    


-- 
Regards
Vladimir 'φ-coder/phcoder' Serbinenko

Re: LiveCD bootloader

[Robert Millan]

2010/9/8, Teresa e Junior <teresaejunior@gmail.com>:
> But due to some features I need (not the eyecandy), I noticed the CD
> only boots without gfx support (which is the most important for me).

You need to write a grub.cfg for that.  Check this one as an example
and adjust to your liking:

http://svn.debian.org/viewsvn/d-i/trunk/installer/build/boot/kfreebsd/grub-kfreebsd-cdrom.cfg?revision=64460&view=markup

-- 
Robert Millan

Re: LiveCD bootloader

[Teresa e Junior]

On Wed, 8 Sep 2010 10:36:35 +0200
Robert Millan <rmh@gnu.org> wrote:

> 2010/9/8, Teresa e Junior <teresaejunior@gmail.com>:
> > But due to some features I need (not the eyecandy), I noticed the CD
> > only boots without gfx support (which is the most important for me).
> 
> You need to write a grub.cfg for that.  Check this one as an example
> and adjust to your liking:
> 
> http://svn.debian.org/viewsvn/d-i/trunk/installer/build/boot/kfreebsd/grub-kfreebsd-cdrom.cfg?revision=64460&view=markup
> 

Thanks, from it I can see some mistakes I committed!

future of grub commands setup and install ?

[Treutwein Bernhard]

according to the wiki the commands install & setup are "unecessary".

I do consider setup (which itself uses install) as "desirable" at least. 

What are the opinions about it?

Background: I rarely have Linux installed on systems, where I'd like to put
grub on and I have used setup to put grub there (see:
http://www.lrz.de/~bernhard/grub-oberon.html).

regards & thanks in advance
--
  Bernhard

Re: future of grub commands setup and install ?

[Robert Millan]

2010/9/9, Treutwein Bernhard <Bernhard.Treutwein@verwaltung.uni-muenchen.de>:
> according to the wiki the commands install & setup are "unecessary".
>
> I do consider setup (which itself uses install) as "desirable" at least.

GRUB lacks filesystem write support (intentionally).  Therefore, installing
GRUB from GRUB is not possible.  Given that setup command can only
perform part of this, it is unrealistic to pretend setup command is useful.
This is why it was removed.

-- 
Robert Millan

Re: future of grub commands setup and install ?

[Vladimir 'φ-coder/phcoder' Serbinenko]

On 09/09/10 14:14, Robert Millan wrote:
> 2010/9/9, Treutwein Bernhard<Bernhard.Treutwein@verwaltung.uni-muenchen.de>:
>    
>> according to the wiki the commands install&  setup are "unecessary".
>>
>> I do consider setup (which itself uses install) as "desirable" at least.
>>      
> GRUB lacks filesystem write support (intentionally).  Therefore, installing
> GRUB from GRUB is not possible.  Given that setup command can only
> perform part of this, it is unrealistic to pretend setup command is useful.
> This is why it was removed.
>
>    
OTOH it should be realistic to port GRUB to any OS having GCC and decent 
binutils, I hope Bluebottle is included (I don't have a lot of 
experience with it even though it';s developped at my university).
Also it would be a good idea to distribute a free kernel (e.g. 
linux-libre) with a small initramfs with busybox, few useless tools and 
GRUB. This would be esily loadable from GRUB regardless of media and 
will be able to perform all GRUB-related tasks except compiling.


-- 
Regards
Vladimir 'φ-coder/phcoder' Serbinenko

RE: future of grub commands setup and install ?

[Treutwein Bernhard]

> > I do consider setup (which itself uses install) as 
> "desirable" at least.
> 
> GRUB lacks filesystem write support (intentionally).  
> Therefore, installing GRUB from GRUB is not possible.  
> 

but installation in MBR or PBR does not need filesystem 
support

> Given that setup command can only perform part of this, 
> it is unrealistic to pretend setup command is useful.
> 

have I misunderstood the functioning of setup in Grub legacy:

It checks the availability of the files in the filesystem and
copies the necessary stuff (including the block "pointers") to
MBR or PBR. In this case it needs only read access to the file
system. 

Otherwise: please give me some tutorial, what it does.

regards
--
  Bernhard 

Re: LiveCD bootloader

[Andreas Born]

Hi,

we're building our LiveCD with Grub2. You can have a look at the config 
files we use/generate here: 
http://salix.svn.sourceforge.net/viewvc/salix/salix-live/trunk/livegrub2/
The other live stuff in general is here: 
http://salix.svn.sourceforge.net/viewvc/salix/salix-live/trunk/
For the buildscript look here (scroll towards the end for the grub2 
related stuff): 
http://salix.svn.sourceforge.net/viewvc/salix/salix-live/trunk/build-salixlive.sh?revision=1638

There are some issues though:
  - Black border displayed around the initial splash screen (maybe fixed 
in trunk, haven't read so on the maillist)
  - Starting Grub2 fails on my pretty new desktop (the only such report 
as far as I'm concerned)
  - Graphics are pretty slow

Andreas

Am 08.09.2010 04:42, schrieb Teresa e Junior:
> Hello, GRUB developers!
>
> I'm fighting to replace isolinux with GRUB2 in the Live System I'm
> about to release. I already got the CD to boot with GRUB2, generating
> the ISO with grub-mkrescue. I think there must be some smarter way to
> do this, but I can't find out.
>
> But due to some features I need (not the eyecandy), I noticed the CD
> only boots without gfx support (which is the most important for me).
>
> I already tried using --modules="linux ext2 fshelp ls boot pc coreui vbe
> png jpeg gettext gfxmode" without any success. Tried some burg-mkisofs
> and xorriso commands, but I believe I miss something. Typing
> `configfile /grub.cfg' won't help either.
>
> Your help will be very appreciated, for we've been struggling for not
> a few hours!
>
> Teresa e Junior
>
> _______________________________________________
> Grub-devel mailing list
> Grub-devel@gnu.org
> http://lists.gnu.org/mailman/listinfo/grub-devel
>    

Re: LiveCD bootloader

[Colin Watson]

On Wed, Sep 08, 2010 at 05:28:07PM +0200, Andreas Born wrote:
> There are some issues though:
>  - Black border displayed around the initial splash screen (maybe fixed  
> in trunk, haven't read so on the maillist)

Not fixed.  See:

  http://lists.gnu.org/archive/html/grub-devel/2010-07/msg00057.html

>  - Starting Grub2 fails on my pretty new desktop (the only such report  
> as far as I'm concerned)

Fails how?

>  - Graphics are pretty slow

Might be related to:

  http://lists.gnu.org/archive/html/grub-devel/2010-06/msg00129.html

-- 
Colin Watson                                       [cjwatson@ubuntu.com]

GRUB2 fails when booting from CD

[Andreas Born]

Am 08.09.2010 17:46, schrieb Colin Watson:
> On Wed, Sep 08, 2010 at 05:28:07PM +0200, Andreas Born wrote:
>    
>>   - Starting Grub2 fails on my pretty new desktop (the only such report
>> as far as I'm concerned)
>>      
> Fails how?
>    
After selecting to boot from cdrom in the bios it outputs the following:
Welcome to GRUB!

error: hd111 cannot get C/H/S values.
Enetering rescue mode...
grub rescue>

Then I'm at the rescue prompt.

The problem is reproducible with SalixLive or a minimal image I've 
created for testing purpose, but so far only on that one machine of 
mine. You can acquire the latter here: 
http://gaia.homelinux.org/misc/grub-test.iso (4.3M)

I've experimented a bit with ls on the rescue prompt here's the output:
 > ls
(hd0)
 > ls (hd0)
error: unknown filesystem

If you need anything else, just let me know and I'll try to do my best 
to help you.

Regards,
Andreas

Re: GRUB2 fails when booting from CD

[Andreas Born]

ping

Am 08.09.2010 18:31, schrieb Andreas Born:
> Am 08.09.2010 17:46, schrieb Colin Watson:
>> On Wed, Sep 08, 2010 at 05:28:07PM +0200, Andreas Born wrote:
>>>   - Starting Grub2 fails on my pretty new desktop (the only such report
>>> as far as I'm concerned)
>> Fails how?
> After selecting to boot from cdrom in the bios it outputs the following:
> Welcome to GRUB!
>
> error: hd111 cannot get C/H/S values.
> Enetering rescue mode...
> grub rescue>
>
> Then I'm at the rescue prompt.
>
> The problem is reproducible with SalixLive or a minimal image I've 
> created for testing purpose, but so far only on that one machine of 
> mine. You can acquire the latter here: 
> http://gaia.homelinux.org/misc/grub-test.iso (4.3M)
>
> I've experimented a bit with ls on the rescue prompt here's the output:
> > ls
> (hd0)
> > ls (hd0)
> error: unknown filesystem
>
> If you need anything else, just let me know and I'll try to do my best 
> to help you.
>
> Regards,
> Andreas

Re: GRUB2 fails when booting from CD

[Phillip Susi]

It sounds like you built the iso to use hd emulation instead of native
el-torito boot, and you don't have the correct modules built into the
core image.  Either that or if hd0 actually is the hard disk and not an
emulated one, you don't have the partition table module built into the core.

On 9/26/2010 4:22 PM, Andreas Born wrote:
>>> Fails how?
>> After selecting to boot from cdrom in the bios it outputs the following:
>> Welcome to GRUB!
>>
>> error: hd111 cannot get C/H/S values.
>> Enetering rescue mode...
>> grub rescue>
>>
>> Then I'm at the rescue prompt.
>>
>> The problem is reproducible with SalixLive or a minimal image I've
>> created for testing purpose, but so far only on that one machine of
>> mine. You can acquire the latter here:
>> http://gaia.homelinux.org/misc/grub-test.iso (4.3M)
>>
>> I've experimented a bit with ls on the rescue prompt here's the output:
>> > ls
>> (hd0)
>> > ls (hd0)
>> error: unknown filesystem

Re: GRUB2 fails when booting from CD

[Andreas Born]

Am 28.09.2010 20:11, schrieb Phillip Susi:
> On 9/28/2010 12:37 PM, Andreas Born wrote:
>    
>> If I understood that part about hd emulation right, that would mean the
>> image wouldn't work on any machine? Or is it possible to switch
>> dynamically with one single image between hd emulation and native
>> el-torito?
>>      
> That's true, if that were the problem the image would not work on any
> machine.  If it works on other machines, then it seems to be a problem
> with the bios.
>
>    
>> Output:
>> grub rescue>  set
>> prefix=(hd111)/boot/grub/i386-pc/
>> root=hd111
>>      
> The odd ( 111 ) hd number is a hint that the bios is broken.  Does ls
> report any available drives?  Maybe it is there, but the bios did not
> pass the correct number.
>    
Yes, as I wrote in my first mail:

grub rescue>  ls
(hd0)
grub rescue>  ls (hd0)
error: unknown filesystem

Is there any way to clearly identify the BIOS as the culprit? Or maybe 
even a chance to implement a workardound at some point if it really is a 
problem with the BIOS?
I guess the fact that I don't have such problems with isolinux can be 
explained with different use of BIOS functionality?
I'm not asking because it were a serious problem for me. I'd just like 
to lower the probability that other users face unlike me a real problem. 
At least if it's possible with considerable effort.

Re: GRUB2 fails when booting from CD

[Vladimir 'φ-coder/phcoder' Serbinenko]

[-- Attachment #1.1: Type: text/plain, Size: 1443 bytes --]

On 09/08/2010 06:31 PM, Andreas Born wrote:
> Am 08.09.2010 17:46, schrieb Colin Watson:
>> On Wed, Sep 08, 2010 at 05:28:07PM +0200, Andreas Born wrote:
>>   
>>>   - Starting Grub2 fails on my pretty new desktop (the only such report
>>> as far as I'm concerned)
>>>      
>> Fails how?
>>    
> After selecting to boot from cdrom in the bios it outputs the following:
> Welcome to GRUB!
>
> error: hd111 cannot get C/H/S values.
> Enetering rescue mode...
> grub rescue>
>
> Then I'm at the rescue prompt.
>
Looks like your BIOS has problems with cd drive. I attach 2 patches. One
to try to gather more info for better workaround and another one to
basically ignore cdinfo altogether. Could you test them?
> The problem is reproducible with SalixLive or a minimal image I've
> created for testing purpose, but so far only on that one machine of
> mine. You can acquire the latter here:
> http://gaia.homelinux.org/misc/grub-test.iso (4.3M)
>
> I've experimented a bit with ls on the rescue prompt here's the output:
> > ls
> (hd0)
> > ls (hd0)
> error: unknown filesystem
>
> If you need anything else, just let me know and I'll try to do my best
> to help you.
>
> Regards,
> Andreas
>
> _______________________________________________
> Grub-devel mailing list
> Grub-devel@gnu.org
> http://lists.gnu.org/mailman/listinfo/grub-devel
>


-- 
Regards
Vladimir 'φ-coder/phcoder' Serbinenko


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[-- Type: text/x-diff; name="cdfailinf.diff", Size: 978 bytes --]

=== modified file 'grub-core/disk/i386/pc/biosdisk.c'
--- grub-core/disk/i386/pc/biosdisk.c	2010-09-18 22:04:31 +0000
+++ grub-core/disk/i386/pc/biosdisk.c	2010-12-25 20:41:28 +0000
@@ -620,10 +620,19 @@
   grub_memset (cdrp, 0, sizeof (*cdrp));
   cdrp->size = sizeof (*cdrp);
   cdrp->media_type = 0xFF;
-  if ((! grub_biosdisk_get_cdinfo_int13_extensions (grub_boot_drive, cdrp)) &&
-      ((cdrp->media_type & GRUB_BIOSDISK_CDTYPE_MASK)
-       == GRUB_BIOSDISK_CDTYPE_NO_EMUL))
-    cd_drive = cdrp->drive_no;
+  {
+    int a;
+    a = grub_biosdisk_get_cdinfo_int13_extensions (grub_boot_drive, cdrp);
+    
+    if ((! a) && 0 &&
+	((cdrp->media_type & GRUB_BIOSDISK_CDTYPE_MASK)
+	 == GRUB_BIOSDISK_CDTYPE_NO_EMUL))
+      cd_drive = cdrp->drive_no;
+    grub_printf ("%d %x %x\n", a, cdrp->media_type, cdrp->drive_no);
+    grub_getkey ();
+    grub_getkey ();
+    grub_getkey ();
+  }
 
   grub_disk_dev_register (&grub_biosdisk_dev);
 }


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[-- Type: text/x-diff; name="cdfailwa.diff", Size: 463 bytes --]

=== modified file 'grub-core/disk/i386/pc/biosdisk.c'
--- grub-core/disk/i386/pc/biosdisk.c	2010-09-18 22:04:31 +0000
+++ grub-core/disk/i386/pc/biosdisk.c	2010-12-25 20:42:08 +0000
@@ -624,6 +624,8 @@
       ((cdrp->media_type & GRUB_BIOSDISK_CDTYPE_MASK)
        == GRUB_BIOSDISK_CDTYPE_NO_EMUL))
     cd_drive = cdrp->drive_no;
+  if (grub_boot_drive >= 0x90)
+    cd_drive = grub_boot_drive;
 
   grub_disk_dev_register (&grub_biosdisk_dev);
 }


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Re: GRUB2 fails when booting from CD

[Andreas Born]

Ok, here you go. I created the same iso image I referred to earlier in 
this thread with grub 1.98 and cdfailinf/cdfailwa patch applied.

cdfailinf (broken machine): 0 0 0
cdfailinf (working machine): 0 0 9f

cdfailwa brings up the menu on the broken machine and on another working 
machine, where I tested it too.

Hope that helps.

Regards,
Andreas


Am 25.12.2010 21:45, schrieb Vladimir 'φ-coder/phcoder' Serbinenko:
> On 09/08/2010 06:31 PM, Andreas Born wrote:
>    
>> Am 08.09.2010 17:46, schrieb Colin Watson:
>>      
>>> On Wed, Sep 08, 2010 at 05:28:07PM +0200, Andreas Born wrote:
>>>
>>>        
>>>>    - Starting Grub2 fails on my pretty new desktop (the only such report
>>>> as far as I'm concerned)
>>>>
>>>>          
>>> Fails how?
>>>
>>>        
>> After selecting to boot from cdrom in the bios it outputs the following:
>> Welcome to GRUB!
>>
>> error: hd111 cannot get C/H/S values.
>> Enetering rescue mode...
>> grub rescue>
>>
>> Then I'm at the rescue prompt.
>>
>>      
> Looks like your BIOS has problems with cd drive. I attach 2 patches. One
> to try to gather more info for better workaround and another one to
> basically ignore cdinfo altogether. Could you test them?
>    
>> The problem is reproducible with SalixLive or a minimal image I've
>> created for testing purpose, but so far only on that one machine of
>> mine. You can acquire the latter here:
>> http://gaia.homelinux.org/misc/grub-test.iso (4.3M)
>>
>> I've experimented a bit with ls on the rescue prompt here's the output:
>>      
>>> ls
>>>        
>> (hd0)
>>      
>>> ls (hd0)
>>>        
>> error: unknown filesystem
>>
>> If you need anything else, just let me know and I'll try to do my best
>> to help you.
>>
>> Regards,
>> Andreas
>>
>> _______________________________________________
>> Grub-devel mailing list
>> Grub-devel@gnu.org
>> http://lists.gnu.org/mailman/listinfo/grub-devel
>>
>>      
>
>    

Re: GRUB2 fails when booting from CD

[Vladimir 'φ-coder/phcoder' Serbinenko]

[-- Attachment #1: Type: text/plain, Size: 2407 bytes --]

On 12/27/2010 01:30 PM, Andreas Born wrote:
> Ok, here you go. I created the same iso image I referred to earlier in
> this thread with grub 1.98 and cdfailinf/cdfailwa patch applied.
>
> cdfailinf (broken machine): 0 0 0
> cdfailinf (working machine): 0 0 9f
>
Jusging from this output a smaller workaround is enough for your
machine. However I committed cdfailwa as it will probably workaround
some more BIOSes with similar problem.
Thanks for reporting and testing.
> cdfailwa brings up the menu on the broken machine and on another
> working machine, where I tested it too.
>
> Hope that helps.
>
> Regards,
> Andreas
>
>
> Am 25.12.2010 21:45, schrieb Vladimir 'φ-coder/phcoder' Serbinenko:
>> On 09/08/2010 06:31 PM, Andreas Born wrote:
>>   
>>> Am 08.09.2010 17:46, schrieb Colin Watson:
>>>     
>>>> On Wed, Sep 08, 2010 at 05:28:07PM +0200, Andreas Born wrote:
>>>>
>>>>       
>>>>>    - Starting Grub2 fails on my pretty new desktop (the only such
>>>>> report
>>>>> as far as I'm concerned)
>>>>>
>>>>>          
>>>> Fails how?
>>>>
>>>>        
>>> After selecting to boot from cdrom in the bios it outputs the
>>> following:
>>> Welcome to GRUB!
>>>
>>> error: hd111 cannot get C/H/S values.
>>> Enetering rescue mode...
>>> grub rescue>
>>>
>>> Then I'm at the rescue prompt.
>>>
>>>      
>> Looks like your BIOS has problems with cd drive. I attach 2 patches. One
>> to try to gather more info for better workaround and another one to
>> basically ignore cdinfo altogether. Could you test them?
>>   
>>> The problem is reproducible with SalixLive or a minimal image I've
>>> created for testing purpose, but so far only on that one machine of
>>> mine. You can acquire the latter here:
>>> http://gaia.homelinux.org/misc/grub-test.iso (4.3M)
>>>
>>> I've experimented a bit with ls on the rescue prompt here's the output:
>>>     
>>>> ls
>>>>        
>>> (hd0)
>>>     
>>>> ls (hd0)
>>>>        
>>> error: unknown filesystem
>>>
>>> If you need anything else, just let me know and I'll try to do my best
>>> to help you.
>>>
>>> Regards,
>>> Andreas
>>>
>>> _______________________________________________
>>> Grub-devel mailing list
>>> Grub-devel@gnu.org
>>> http://lists.gnu.org/mailman/listinfo/grub-devel
>>>
>>>      
>>
>>    
>
>


-- 
Regards
Vladimir 'φ-coder/phcoder' Serbinenko



[-- Attachment #2: OpenPGP digital signature --]
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Re: LiveCD bootloader

[Teresa e Junior]

On Wed, 08 Sep 2010 17:28:07 +0200
Andreas Born <futur.andy@googlemail.com> wrote:

> Hi,
> 
> we're building our LiveCD with Grub2. You can have a look at the
> config files we use/generate here: 
> http://salix.svn.sourceforge.net/viewvc/salix/salix-live/trunk/livegrub2/
> The other live stuff in general is here: 
> http://salix.svn.sourceforge.net/viewvc/salix/salix-live/trunk/
> For the buildscript look here (scroll towards the end for the grub2 
> related stuff): 
> http://salix.svn.sourceforge.net/viewvc/salix/salix-live/trunk/build-salixlive.sh?revision=1638
> 
> There are some issues though:
>   - Black border displayed around the initial splash screen (maybe
> fixed in trunk, haven't read so on the maillist)
>   - Starting Grub2 fails on my pretty new desktop (the only such
> report as far as I'm concerned)
>   - Graphics are pretty slow
> 
> Andreas
> 
> Am 08.09.2010 04:42, schrieb Teresa e Junior:
> > Hello, GRUB developers!
> >
> > I'm fighting to replace isolinux with GRUB2 in the Live System I'm
> > about to release. I already got the CD to boot with GRUB2,
> > generating the ISO with grub-mkrescue. I think there must be some
> > smarter way to do this, but I can't find out.
> >
> > But due to some features I need (not the eyecandy), I noticed the CD
> > only boots without gfx support (which is the most important for me).
> >
> > I already tried using --modules="linux ext2 fshelp ls boot pc
> > coreui vbe png jpeg gettext gfxmode" without any success. Tried
> > some burg-mkisofs and xorriso commands, but I believe I miss
> > something. Typing `configfile /grub.cfg' won't help either.
> >
> > Your help will be very appreciated, for we've been struggling for
> > not a few hours!
> >
> > Teresa e Junior
> >
> > _______________________________________________
> > Grub-devel mailing list
> > Grub-devel@gnu.org
> > http://lists.gnu.org/mailman/listinfo/grub-devel
> >    
> 
> 
> _______________________________________________
> Grub-devel mailing list
> Grub-devel@gnu.org
> http://lists.gnu.org/mailman/listinfo/grub-devel

Thank you, very helpful!